Alert archive / Texas / Flash Flood Watches in 2021

Flash Flood Watch 1, NWS Houston/Galveston, TX

April 29, 202123 counties in Texas

NWS Houston/Galveston, TX issued this flash flood watch at Apr 29, 2021, 9:33 PM CDT for 23 counties in Texas. It took effect at Apr 29, 2021, 10:00 PM CDT. It was in force for 55 hr.

The area

The counties it named.

The facts

Issued
Apr 29, 2021, 9:33 PM CDT (02:33 UTC)
In effect from
Apr 29, 2021, 10:00 PM CDT
Expired
May 2, 2021, 4:51 AM CDT
In force
55 hr
Issued by
NWS Houston/Galveston, TX
Flood severity
None
All 23 counties

Austin County, TX, Brazoria County, TX, Brazos County, TX, Burleson County, TX, Chambers County, TX, Colorado County, TX, Fort Bend County, TX, Galveston County, TX, Grimes County, TX, Harris County, TX, Houston County, TX, Jackson County, TX, Liberty County, TX, Madison County, TX, Matagorda County, TX, Montgomery County, TX, Polk County, TX, San Jacinto County, TX, Trinity County, TX, Walker County, TX, Waller County, TX, Washington County, TX, Wharton County, TX

The radar

The Houston radar (KHGX), 91 km from the middle of the area, began a volume at 02:35 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Lake Charles Mun, LA (KLCH), launched 00:00Z, 2.6 hours before the alert went out and 242 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Lake Charles Mun, LA at 00:00Z on 2021-04-30Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1081 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Lake Charles Mun, LA at 00:00Z on 2021-04-30The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -21 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
1081 J/kg
Mixed-layer CIN
-32 J/kg
Mixed-layer LCL
811 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
-21 m²/s²
0-3 km storm-relative helicity
22 m²/s²
Significant tornado parameter
0.1
Supercell composite
0.7

Open this sounding in Storm Lab

The text

As transmitted.

989 
WGUS64 KHGX 300233
FFAHGX

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service Houston/Galveston TX
933 PM CDT Thu Apr 29 2021

TXZ163-164-176>179-195>200-301045-
/O.NEW.KHGX.FF.A.0001.210430T0300Z-210502T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Houston-Trinity-Madison-Walker-San Jacinto-Polk-Burleson-Brazos-
Washington-Grimes-Montgomery-Northern Liberty-
Including the cities of Shepherd, Cleveland, Groveton, Dayton, 
Bryan, Huntsville, Corrigan, Crockett, Liberty, Navasota, Caldwell, 
Livingston, Conroe, Brenham, Coldspring, College Station, The 
Woodlands, Somerville, Trinity, and Madisonville
933 PM CDT Thu Apr 29 2021

...FLASH FLOOD WATCH IN EFFECT THROUGH SUNDAY MORNING...

The National Weather Service in League City has issued a

* Flash Flood Watch for a portion of southeast Texas, including the 
  following areas, Brazos, Burleson, Grimes, Houston, Madison, 
  Montgomery, Northern Liberty, Polk, San Jacinto, Trinity, Walker 
  and Washington.

* Through Sunday morning

* Showers and thunderstorms are expected to develop overnight as a 
  cold front slowly sags southward. A widespread 1 to 3 inches of 
  rain is expected, but training of heavier storms may produce 
  localized areas of 4 to 8 inches of rainfall.

* Flooding of low-lying, poorly draining areas and other vulnerable 
  locations are possible if they are impacted by storms with heavier 
  rainfall rates and amounts. Multiple rounds of these storms would 
  worsen the potential for flooding. Where rain rates are more 
  manageable, previously dry conditions will help reduce concerns 
  for flooding.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead to 
Flash Flooding. Flash Flooding is a very dangerous situation. You 
should monitor later forecasts and be prepared to take action should 
Flash Flood Warnings be issued.

&&

$$

TXZ210>214-226-227-235>238-300-313-335>338-436>439-301045-
/O.NEW.KHGX.FF.A.0001.210501T0900Z-210502T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Colorado-Austin-Waller-Inland Harris-Chambers-Wharton-Fort Bend-
Inland Jackson-Inland Matagorda-Inland Brazoria-Inland Galveston-
Southern Liberty-Coastal Harris-Coastal Jackson-Coastal Matagorda-
Coastal Brazoria-Coastal Galveston-Matagorda Islands-Brazoria
Islands-Galveston Island-Bolivar Peninsula-
Including the cities of Brookshire, Pearland, Waller, Texas City, 
Dickinson, Pasadena, Anahuac, Baytown, Bellville, Bay City, 
Columbus, Surfside Beach, Hempstead, Wharton, Missouri City, Pecan 
Grove, Palacios, League City, La Marque, Lake Jackson, Mont Belvieu, 
Old River-Winfree, Freeport, First Colony, Clute, Eagle Lake, 
Mission Bend, Stowell, Sugar Land, Galveston, Houston, Prairie View, 
Sealy, Rosenberg, Friendswood, Winnie, Alvin, Ganado, El Campo, 
Edna, Devers, Angleton, and Weimar
933 PM CDT Thu Apr 29 2021

...FLASH FLOOD WATCH IN EFFECT FROM LATE FRIDAY NIGHT THROUGH SUNDAY 
MORNING...

The National Weather Service in League City has issued a

* Flash Flood Watch for portions of south central Texas and 
  southeast Texas, including the following areas, in south central 
  Texas, Coastal Jackson and Inland Jackson. In southeast Texas, 
  Austin, Bolivar Peninsula, Brazoria Islands, Chambers, Coastal 
  Brazoria, Coastal Galveston, Coastal Harris, Coastal Matagorda, 
  Colorado, Fort Bend, Galveston Island, Inland Brazoria, Inland 
  Galveston, Inland Harris, Inland Matagorda, Matagorda Islands, 
  Southern Liberty, Waller and Wharton.

* From late Friday night through Sunday morning

* Showers and thunderstorms are expected to move in from the north 
  early Friday morning as a cold front moves slowly coastward. A 
  widespread 1 to 3 inches of rain is expected, but training of 
  heavier storms can produce localized areas of 4 to 8 inches of 
  rainfall. An isolated spot or two of 10 inches or more by Friday 
  evening may be possible.

* Flooding of low-lying, poorly draining areas and other vulnerable 
  locations such as easily-flooded streets are possible if they are 
  impacted by storms with heavier rainfall rates and amounts. 
  Multiple rounds of these storms would worsen the potential for 
  flooding. Where rain rates are more manageable, previously dry 
  conditions will help reduce concerns for flooding.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead to 
Flash Flooding. Flash Flooding is a very dangerous situation. You 
should monitor later forecasts and be prepared to take action should 
Flash Flood Warnings be issued.

&&

$$

SPL
9 follow-up statements
630 
WGUS64 KHGX 300236
FFAHGX

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service Houston/Galveston TX
936 PM CDT Thu Apr 29 2021

TXZ210>214-226-227-235>238-300-313-335>338-436>439-301045-
/O.EXT.KHGX.FF.A.0001.210430T0900Z-210502T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Colorado-Austin-Waller-Inland Harris-Chambers-Wharton-Fort Bend-
Inland Jackson-Inland Matagorda-Inland Brazoria-Inland Galveston-
Southern Liberty-Coastal Harris-Coastal Jackson-Coastal Matagorda-
Coastal Brazoria-Coastal Galveston-Matagorda Islands-Brazoria
Islands-Galveston Island-Bolivar Peninsula-
Including the cities of Brookshire, Pearland, Waller, Texas City, 
Dickinson, Pasadena, Anahuac, Baytown, Bellville, Bay City, 
Columbus, Surfside Beach, Hempstead, Wharton, Missouri City, Pecan 
Grove, Palacios, League City, La Marque, Lake Jackson, Mont Belvieu, 
Old River-Winfree, Freeport, First Colony, Clute, Eagle Lake, 
Mission Bend, Stowell, Sugar Land, Galveston, Houston, Prairie View, 
Sealy, Rosenberg, Friendswood, Winnie, Alvin, Ganado, El Campo, 
Edna, Devers, Angleton, and Weimar
936 PM CDT Thu Apr 29 2021

...FLASH FLOOD WATCH CORRECTED TO BE IN EFFECT FROM 4 AM CDT FRIDAY 
THROUGH SUNDAY MORNING...

The Flash Flood Watch is now in effect for

* Portions of south central Texas and southeast Texas, including the 
  following areas, in south central Texas, Coastal Jackson and 
  Inland Jackson. In southeast Texas, Austin, Bolivar Peninsula, 
  Brazoria Islands, Chambers, Coastal Brazoria, Coastal Galveston, 
  Coastal Harris, Coastal Matagorda, Colorado, Fort Bend, Galveston 
  Island, Inland Brazoria, Inland Galveston, Inland Harris, Inland 
  Matagorda, Matagorda Islands, Southern Liberty, Waller and Wharton.

* From 4 AM CDT Friday through Sunday morning

* Showers and thunderstorms are expected to move in from the north 
  early Friday morning as a cold front moves slowly coastward. A 
  widespread 1 to 3 inches of rain is expected, but training of 
  heavier storms can produce localized areas of 4 to 8 inches of 
  rainfall. An isolated spot or two of 10 inches or more by Friday 
  evening may be possible.

* Flooding of low-lying, poorly draining areas and other vulnerable 
  locations such as easily-flooded streets are possible if they are 
  impacted by storms with heavier rainfall rates and amounts. 
  Multiple rounds of these storms would worsen the potential for 
  flooding. Where rain rates are more manageable, previously dry 
  conditions will help reduce concerns for flooding.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead to 
Flash Flooding. Flash Flooding is a very dangerous situation. You 
should monitor later forecasts and be prepared to take action should 
Flash Flood Warnings be issued.

&&

$$

TXZ163-164-176>179-195>200-301045-
/O.CON.KHGX.FF.A.0001.210430T0300Z-210502T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Houston-Trinity-Madison-Walker-San Jacinto-Polk-Burleson-Brazos-
Washington-Grimes-Montgomery-Northern Liberty-
Including the cities of Shepherd, Cleveland, Groveton, Dayton, 
Bryan, Huntsville, Corrigan, Crockett, Liberty, Navasota, Caldwell, 
Livingston, Conroe, Brenham, Coldspring, College Station, The 
Woodlands, Somerville, Trinity, and Madisonville
936 PM CDT Thu Apr 29 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH SUNDAY MORNING...

The Flash Flood Watch continues for

* A portion of southeast Texas, including the following areas, 
  Brazos, Burleson, Grimes, Houston, Madison, Montgomery, Northern 
  Liberty, Polk, San Jacinto, Trinity, Walker and Washington.

* Through Sunday morning

* Showers and thunderstorms are expected to develop overnight as a 
  cold front slowly sags southward. A widespread 1 to 3 inches of 
  rain is expected, but training of heavier storms may produce 
  localized areas of 4 to 8 inches of rainfall.

* Flooding of low-lying, poorly draining areas and other vulnerable 
  locations are possible if they are impacted by storms with heavier 
  rainfall rates and amounts. Multiple rounds of these storms would 
  worsen the potential for flooding. Where rain rates are more 
  manageable, previously dry conditions will help reduce concerns 
  for flooding.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead to 
Flash Flooding. Flash Flooding is a very dangerous situation. You 
should monitor later forecasts and be prepared to take action should 
Flash Flood Warnings be issued.

&&

$$

SPL
536 
WGUS64 KHGX 300851
FFAHGX

Flood Watch
National Weather Service Houston/Galveston TX
351 AM CDT Fri Apr 30 2021

TXZ163-164-176>179-195>200-301900-
/O.CON.KHGX.FF.A.0001.000000T0000Z-210502T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Houston-Trinity-Madison-Walker-San Jacinto-Polk-Burleson-Brazos-
Washington-Grimes-Montgomery-Northern Liberty-
Including the cities of Shepherd, Cleveland, Groveton, Dayton, 
Bryan, Huntsville, Corrigan, Crockett, Liberty, Navasota, Caldwell, 
Livingston, Conroe, Brenham, Coldspring, College Station, The 
Woodlands, Somerville, Trinity, and Madisonville
351 AM CDT Fri Apr 30 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH SUNDAY MORNING...

The Flash Flood Watch continues for

* A portion of southeast Texas, including the following areas, 
  Brazos, Burleson, Grimes, Houston, Madison, Montgomery, Northern 
  Liberty, Polk, San Jacinto, Trinity, Walker and Washington.

* Through Sunday morning

* Showers and thunderstorms with heavy rain were ongoing early this 
  morning across portions of the Flash Flood Watch area. These 
  storms area expected to sag southward through the morning bringing 
  heavy downpours with additional rainfall accumulations of 3 to 6 
  inches possible today. Storms may weaken or depart the area by 
  late afternoon but more storms are expected late Saturday and 
  through Sunday morning.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead to 
Flash Flooding. Flash Flooding is a very dangerous situation. You 
should monitor later forecasts and be prepared to take action should 
Flash Flood Warnings be issued.

&&

$$

TXZ210>214-226-227-235>238-300-313-335>338-436>439-301900-
/O.CON.KHGX.FF.A.0001.210430T0900Z-210502T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Colorado-Austin-Waller-Inland Harris-Chambers-Wharton-Fort Bend-
Inland Jackson-Inland Matagorda-Inland Brazoria-Inland Galveston-
Southern Liberty-Coastal Harris-Coastal Jackson-Coastal Matagorda-
Coastal Brazoria-Coastal Galveston-Matagorda Islands-Brazoria
Islands-Galveston Island-Bolivar Peninsula-
Including the cities of Brookshire, Pearland, Waller, Texas City, 
Dickinson, Pasadena, Anahuac, Baytown, Bellville, Bay City, 
Columbus, Surfside Beach, Hempstead, Wharton, Missouri City, Pecan 
Grove, Palacios, League City, La Marque, Lake Jackson, Mont Belvieu, 
Old River-Winfree, Freeport, First Colony, Clute, Eagle Lake, 
Mission Bend, Stowell, Sugar Land, Galveston, Houston, Prairie View, 
Sealy, Rosenberg, Friendswood, Winnie, Alvin, Ganado, El Campo, 
Edna, Devers, Angleton, and Weimar
351 AM CDT Fri Apr 30 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH SUNDAY MORNING...

The Flash Flood Watch continues for

* Portions of south central Texas and southeast Texas, including the 
  following areas, in south central Texas, Coastal Jackson and 
  Inland Jackson. In southeast Texas, Austin, Bolivar Peninsula, 
  Brazoria Islands, Chambers, Coastal Brazoria, Coastal Galveston, 
  Coastal Harris, Coastal Matagorda, Colorado, Fort Bend, Galveston 
  Island, Inland Brazoria, Inland Galveston, Inland Harris, Inland 
  Matagorda, Matagorda Islands, Southern Liberty, Waller and Wharton.

* Through Sunday morning

* Showers and thunderstorms will be increasing in coverage over the 
  area this morning and very heavy rainfall rates will be possible. 
  Rainfall rates of 2 to 3 inches per hour will be possible with 
  these slow moving storms. The storms in general should sag 
  southward this morning stalling then shifting back to the west and 
  southwestward this afternoon. Storms may weaken or depart the area 
  by late afternoon or evening but more storms are expected to 
  develop Saturday and through Sunday morning.
  Rainfall totals of 2 to 3 inches will be common with isolated 
  locations receiving 4 to 8 inches through this afternoon.  
  Additional heavy rainfall is expected Saturday into Sunday.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead to 
Flash Flooding. Flash Flooding is a very dangerous situation. You 
should monitor later forecasts and be prepared to take action should 
Flash Flood Warnings be issued.

&&

$$

kp
870 
WGUS64 KHGX 301559
FFAHGX

Flood Watch
National Weather Service Houston/Galveston TX
1059 AM CDT Fri Apr 30 2021

TXZ163-164-176>179-195>200-011100-
/O.CON.KHGX.FF.A.0001.000000T0000Z-210502T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Houston-Trinity-Madison-Walker-San Jacinto-Polk-Burleson-Brazos-
Washington-Grimes-Montgomery-Northern Liberty-
Including the cities of Shepherd, Cleveland, Groveton, Dayton, 
Bryan, Huntsville, Corrigan, Crockett, Liberty, Navasota, Caldwell, 
Livingston, Conroe, Brenham, Coldspring, College Station, The 
Woodlands, Somerville, Trinity, and Madisonville
1059 AM CDT Fri Apr 30 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH SUNDAY MORNING...

The Flash Flood Watch continues for

* A portion of southeast Texas, including the following areas, 
  Brazos, Burleson, Grimes, Houston, Madison, Montgomery, Northern 
  Liberty, Polk, San Jacinto, Trinity, Walker and Washington.

* Through Sunday morning

* A nearly stationary boundary draped across Southeast Texas will 
  serve as a boundary for additional showers and thunderstorms 
  through the early afternoon. Moisture will be pulled westward 
  later today and rain chances should begin to diminish later this 
  afternoon. Some parts of Southeast Texas from Waller county to 
  Trinity county received between 4 and 8 inches of rain early this 
  morning. Additional heavy rain will be possible late tonight into 
  Saturday.

* Flooding of low-lying, poorly draining areas and other vulnerable 
  locations are possible if they are impacted by storms with heavier 
  rainfall rates and amounts. Multiple rounds of these storms would 
  worsen the potential for flooding. Where rain rates are more 
  manageable, previously dry conditions will help reduce concerns 
  for flooding.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead to 
Flash Flooding. Flash Flooding is a very dangerous situation. You 
should monitor later forecasts and be prepared to take action should 
Flash Flood Warnings be issued.

&&

$$

TXZ210>214-226-227-235>238-300-313-335>338-436>439-011100-
/O.CON.KHGX.FF.A.0001.000000T0000Z-210502T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Colorado-Austin-Waller-Inland Harris-Chambers-Wharton-Fort Bend-
Inland Jackson-Inland Matagorda-Inland Brazoria-Inland Galveston-
Southern Liberty-Coastal Harris-Coastal Jackson-Coastal Matagorda-
Coastal Brazoria-Coastal Galveston-Matagorda Islands-Brazoria
Islands-Galveston Island-Bolivar Peninsula-
Including the cities of Brookshire, Pearland, Waller, Texas City, 
Dickinson, Pasadena, Anahuac, Baytown, Bellville, Bay City, 
Columbus, Surfside Beach, Hempstead, Wharton, Missouri City, Pecan 
Grove, Palacios, League City, La Marque, Lake Jackson, Mont Belvieu, 
Old River-Winfree, Freeport, First Colony, Clute, Eagle Lake, 
Mission Bend, Stowell, Sugar Land, Galveston, Houston, Prairie View, 
Sealy, Rosenberg, Friendswood, Winnie, Alvin, Ganado, El Campo, 
Edna, Devers, Angleton, and Weimar
1059 AM CDT Fri Apr 30 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH SUNDAY MORNING...

The Flash Flood Watch continues for

* Portions of south central Texas and southeast Texas, including the 
  following areas, in south central Texas, Coastal Jackson and 
  Inland Jackson. In southeast Texas, Austin, Bolivar Peninsula, 
  Brazoria Islands, Chambers, Coastal Brazoria, Coastal Galveston, 
  Coastal Harris, Coastal Matagorda, Colorado, Fort Bend, Galveston 
  Island, Inland Brazoria, Inland Galveston, Inland Harris, Inland 
  Matagorda, Matagorda Islands, Southern Liberty, Waller and Wharton.

* Through Sunday morning

* Showers and thunderstorms will begin to diminish this afternoon as 
  moisture is pulled westward toward an upper level low. As the low 
  approaches late tonight and Saturday, rain chances will once again 
  increase with locally heavy rain possible.

* Flooding of low-lying, poorly draining areas and other vulnerable 
  locations such as easily-flooded streets are possible if they are 
  impacted by storms with heavier rainfall rates and amounts. 
  Multiple rounds of these storms would worsen the potential for 
  flooding. Where rain rates are more manageable, previously dry 
  conditions will help reduce concerns for flooding.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead to 
Flash Flooding. Flash Flooding is a very dangerous situation. You 
should monitor later forecasts and be prepared to take action should 
Flash Flood Warnings be issued.

&&

$$
355 
WGUS64 KHGX 302032
FFAHGX

Flood Watch
National Weather Service Houston/Galveston TX
332 PM CDT Fri Apr 30 2021

TXZ214-300-313-338-302145-
/O.CAN.KHGX.FF.A.0001.000000T0000Z-210502T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Chambers-Southern Liberty-Coastal Harris-Coastal Galveston-
Including the cities of Mont Belvieu, Old River-Winfree, Winnie, 
Devers, Baytown, Texas City, Dickinson, Pasadena, Anahuac, La 
Marque, and Stowell
332 PM CDT Fri Apr 30 2021

...FLASH FLOOD WATCH IS CANCELLED...

The Flash Flood Watch for a portion of southeast Texas, including 
the following areas, Chambers, Coastal Galveston, Coastal Harris and 
Southern Liberty has been cancelled.

The Flood Watch is cancelled.

$$

TXZ163-164-176>179-195>200-011115-
/O.CON.KHGX.FF.A.0001.000000T0000Z-210502T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Houston-Trinity-Madison-Walker-San Jacinto-Polk-Burleson-Brazos-
Washington-Grimes-Montgomery-Northern Liberty-
Including the cities of Shepherd, Cleveland, Groveton, Dayton, 
Bryan, Huntsville, Corrigan, Crockett, Liberty, Navasota, Caldwell, 
Livingston, Conroe, Brenham, Coldspring, College Station, The 
Woodlands, Somerville, Trinity, and Madisonville
332 PM CDT Fri Apr 30 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH SUNDAY MORNING...

The Flash Flood Watch continues for

* A portion of southeast Texas, including the following areas, 
  Brazos, Burleson, Grimes, Houston, Madison, Montgomery, Northern 
  Liberty, Polk, San Jacinto, Trinity, Walker and Washington.

* Through Sunday morning

* Rainfall was between 4 and 9 inches last night into this morning. 
  Additional showers and thunderstorms are expected later tonight 
  into Saturday morning. Some of the rain could again be locally 
  heavy.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead to 
Flash Flooding. Flash Flooding is a very dangerous situation. You 
should monitor later forecasts and be prepared to take action should 
Flash Flood Warnings be issued.

&&

$$

TXZ210>213-226-227-235>238-335>337-436>439-011115-
/O.CON.KHGX.FF.A.0001.000000T0000Z-210502T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Colorado-Austin-Waller-Inland Harris-Wharton-Fort Bend-Inland
Jackson-Inland Matagorda-Inland Brazoria-Inland Galveston-Coastal
Jackson-Coastal Matagorda-Coastal Brazoria-Matagorda Islands-
Brazoria Islands-Galveston Island-Bolivar Peninsula-
Including the cities of Brookshire, Pearland, Bellville, Bay City, 
Columbus, Hempstead, Wharton, Missouri City, Pecan Grove, Palacios, 
League City, Lake Jackson, Surfside Beach, Freeport, First Colony, 
Clute, Eagle Lake, Mission Bend, Waller, Sugar Land, Galveston, 
Houston, Prairie View, Sealy, Rosenberg, Friendswood, Edna, Alvin, 
Ganado, El Campo, Angleton, and Weimar
332 PM CDT Fri Apr 30 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH SUNDAY MORNING...

The Flash Flood Watch continues for

* Portions of south central Texas and southeast Texas, including the 
  following areas, in south central Texas, Coastal Jackson and 
  Inland Jackson. In southeast Texas, Austin, Bolivar Peninsula, 
  Brazoria Islands, Coastal Brazoria, Coastal Matagorda, Colorado, 
  Fort Bend, Galveston Island, Inland Brazoria, Inland Galveston, 
  Inland Harris, Inland Matagorda, Matagorda Islands, Waller and 
  Wharton.

* Through Sunday morning

* 1 To 4 inches of rain fell last night into this morning and 
  additional showers and thunderstorms will be possible later 
  tonight into Saturday. Some of the rain could be locally heavy.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead to 
Flash Flooding. Flash Flooding is a very dangerous situation. You 
should monitor later forecasts and be prepared to take action should 
Flash Flood Warnings be issued.

&&

$$
268 
WGUS64 KHGX 302057
FFAHGX

Flood Watch
National Weather Service Houston/Galveston TX
357 PM CDT Fri Apr 30 2021

TXZ238-439-302200-
/O.CAN.KHGX.FF.A.0001.000000T0000Z-210502T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Inland Galveston-Bolivar Peninsula-
Including the cities of League City and Friendswood
357 PM CDT Fri Apr 30 2021

...FLASH FLOOD WATCH IS CANCELLED...

The Flash Flood Watch for a portion of southeast Texas, including 
the following areas, Bolivar Peninsula and Inland Galveston has been 
cancelled.

The Flood Watch is cancelled.

$$

TXZ163-164-176>179-195>200-010500-
/O.CON.KHGX.FF.A.0001.000000T0000Z-210502T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Houston-Trinity-Madison-Walker-San Jacinto-Polk-Burleson-Brazos-
Washington-Grimes-Montgomery-Northern Liberty-
Including the cities of Shepherd, Cleveland, Groveton, Dayton, 
Bryan, Huntsville, Corrigan, Crockett, Liberty, Navasota, Caldwell, 
Livingston, Conroe, Brenham, Coldspring, College Station, The 
Woodlands, Somerville, Trinity, and Madisonville
357 PM CDT Fri Apr 30 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH SUNDAY MORNING...

The Flash Flood Watch continues for

* A portion of southeast Texas, including the following areas, 
  Brazos, Burleson, Grimes, Houston, Madison, Montgomery, Northern 
  Liberty, Polk, San Jacinto, Trinity, Walker and Washington.

* Through Sunday morning

* Rainfall was between 4 and 9 inches last night into this morning. 
  Additional showers and thunderstorms are expected later tonight 
  into Saturday morning. Some of the rain could again be locally 
  heavy.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead to 
Flash Flooding. Flash Flooding is a very dangerous situation. You 
should monitor later forecasts and be prepared to take action should 
Flash Flood Warnings be issued.

&&

$$

TXZ210>213-226-227-235>237-335>337-436>438-010500-
/O.CON.KHGX.FF.A.0001.000000T0000Z-210502T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Colorado-Austin-Waller-Inland Harris-Wharton-Fort Bend-Inland
Jackson-Inland Matagorda-Inland Brazoria-Coastal Jackson-Coastal
Matagorda-Coastal Brazoria-Matagorda Islands-Brazoria Islands-
Galveston Island-
Including the cities of Brookshire, Pearland, Bellville, Bay City, 
Columbus, Hempstead, Wharton, Missouri City, Pecan Grove, Palacios, 
Lake Jackson, Surfside Beach, Freeport, First Colony, Clute, Eagle 
Lake, Mission Bend, Waller, Sugar Land, Galveston, Houston, Prairie 
View, Sealy, Rosenberg, Edna, Alvin, Ganado, El Campo, Angleton, and 
Weimar
357 PM CDT Fri Apr 30 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH SUNDAY MORNING...

The Flash Flood Watch continues for

* Portions of south central Texas and southeast Texas, including the 
  following areas, in south central Texas, Coastal Jackson and 
  Inland Jackson. In southeast Texas, Austin, Brazoria Islands, 
  Coastal Brazoria, Coastal Matagorda, Colorado, Fort Bend, 
  Galveston Island, Inland Brazoria, Inland Harris, Inland 
  Matagorda, Matagorda Islands, Waller and Wharton.

* Through Sunday morning

* 1 To 4 inches of rain fell last night into this morning and 
  additional showers and thunderstorms will be possible later 
  tonight into Saturday. Some of the rain could be locally heavy.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead to 
Flash Flooding. Flash Flooding is a very dangerous situation. You 
should monitor later forecasts and be prepared to take action should 
Flash Flood Warnings be issued.

&&

$$
921 
WGUS64 KHGX 302105
FFAHGX

Flood Watch
National Weather Service Houston/Galveston TX
405 PM CDT Fri Apr 30 2021

TXZ438-302215-
/O.CAN.KHGX.FF.A.0001.000000T0000Z-210502T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Galveston Island-
Including the cities of Galveston
405 PM CDT Fri Apr 30 2021

...FLASH FLOOD WATCH IS CANCELLED...

The Flash Flood Watch for a portion of southeast Texas, including 
the following area, Galveston Island has been cancelled.

The Flood Watch is cancelled.

$$

TXZ163-164-176>179-195>200-010515-
/O.CON.KHGX.FF.A.0001.000000T0000Z-210502T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Houston-Trinity-Madison-Walker-San Jacinto-Polk-Burleson-Brazos-
Washington-Grimes-Montgomery-Northern Liberty-
Including the cities of Shepherd, Cleveland, Groveton, Dayton, 
Bryan, Huntsville, Corrigan, Crockett, Liberty, Navasota, Caldwell, 
Livingston, Conroe, Brenham, Coldspring, College Station, The 
Woodlands, Somerville, Trinity, and Madisonville
405 PM CDT Fri Apr 30 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH SUNDAY MORNING...

The Flash Flood Watch continues for

* A portion of southeast Texas, including the following areas, 
  Brazos, Burleson, Grimes, Houston, Madison, Montgomery, Northern 
  Liberty, Polk, San Jacinto, Trinity, Walker and Washington.

* Through Sunday morning

* Rainfall was between 4 and 9 inches last night into this morning. 
  Additional showers and thunderstorms are expected later tonight 
  into Saturday morning. Some of the rain could again be locally 
  heavy.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead to 
Flash Flooding. Flash Flooding is a very dangerous situation. You 
should monitor later forecasts and be prepared to take action should 
Flash Flood Warnings be issued.

&&

$$

TXZ210>213-226-227-235>237-335>337-436-437-010515-
/O.CON.KHGX.FF.A.0001.000000T0000Z-210502T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Colorado-Austin-Waller-Inland Harris-Wharton-Fort Bend-Inland
Jackson-Inland Matagorda-Inland Brazoria-Coastal Jackson-Coastal
Matagorda-Coastal Brazoria-Matagorda Islands-Brazoria Islands-
Including the cities of Brookshire, Pearland, Bellville, Bay City, 
Columbus, Hempstead, Wharton, Missouri City, Pecan Grove, Palacios, 
Lake Jackson, Surfside Beach, Freeport, First Colony, Clute, Eagle 
Lake, Mission Bend, Waller, Sugar Land, Houston, Prairie View, 
Sealy, Rosenberg, Edna, Alvin, Ganado, El Campo, Angleton, and Weimar
405 PM CDT Fri Apr 30 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH SUNDAY MORNING...

The Flash Flood Watch continues for

* Portions of south central Texas and southeast Texas, including the 
  following areas, in south central Texas, Coastal Jackson and 
  Inland Jackson. In southeast Texas, Austin, Brazoria Islands, 
  Coastal Brazoria, Coastal Matagorda, Colorado, Fort Bend, Inland 
  Brazoria, Inland Harris, Inland Matagorda, Matagorda Islands, 
  Waller and Wharton.

* Through Sunday morning

* 1 To 4 inches of rain fell last night into this morning and 
  additional showers and thunderstorms will be possible later 
  tonight into Saturday. Some of the rain could be locally heavy.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead to 
Flash Flooding. Flash Flooding is a very dangerous situation. You 
should monitor later forecasts and be prepared to take action should 
Flash Flood Warnings be issued.

&&

$$
882 
WGUS64 KHGX 011013
FFAHGX

Flood Watch
National Weather Service Houston/Galveston TX
513 AM CDT Sat May 1 2021

TXZ163-164-176>179-195>200-011815-
/O.CON.KHGX.FF.A.0001.000000T0000Z-210502T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Houston-Trinity-Madison-Walker-San Jacinto-Polk-Burleson-Brazos-
Washington-Grimes-Montgomery-Northern Liberty-
Including the cities of Shepherd, Cleveland, Groveton, Dayton, 
Bryan, Huntsville, Corrigan, Crockett, Liberty, Navasota, Caldwell, 
Livingston, Conroe, Brenham, Coldspring, College Station, The 
Woodlands, Somerville, Trinity, and Madisonville
513 AM CDT Sat May 1 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH SUNDAY MORNING...

The Flash Flood Watch continues for

* A portion of southeast Texas, including the following areas, 
  Brazos, Burleson, Grimes, Houston, Madison, Montgomery, Northern 
  Liberty, Polk, San Jacinto, Trinity, Walker and Washington.

* Through Sunday morning

* Another round of showers and thunderstorms with moderate to heavy 
  rain were ongoing early this morning. Rainfall totals of 4 to 9 
  inches have already fallen, yesterday. With this new round of 
  precipitation, additional rainfall accumulations of 1 to 2 inches 
  will be possible today. Storms may weaken or depart the area by 
  late afternoon but more storms are expected this evening into 
  Sunday morning.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead to 
Flash Flooding. Flash Flooding is a very dangerous situation. You 
should monitor later forecasts and be prepared to take action should 
Flash Flood Warnings be issued.

Stay away or be swept away. River banks and culverts can become 
unstable and unsafe.

&&

$$

TXZ210>213-226-227-235>237-335>337-436-437-011815-
/O.CON.KHGX.FF.A.0001.000000T0000Z-210502T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Colorado-Austin-Waller-Inland Harris-Wharton-Fort Bend-Inland
Jackson-Inland Matagorda-Inland Brazoria-Coastal Jackson-Coastal
Matagorda-Coastal Brazoria-Matagorda Islands-Brazoria Islands-
Including the cities of Brookshire, Pearland, Bellville, Bay City, 
Columbus, Hempstead, Wharton, Missouri City, Pecan Grove, Palacios, 
Lake Jackson, Surfside Beach, Freeport, First Colony, Clute, Eagle 
Lake, Mission Bend, Waller, Sugar Land, Houston, Prairie View, 
Sealy, Rosenberg, Edna, Alvin, Ganado, El Campo, Angleton, and Weimar
513 AM CDT Sat May 1 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH SUNDAY MORNING...

The Flash Flood Watch continues for

* Portions of south central Texas and southeast Texas, including the 
  following areas, in south central Texas, Coastal Jackson and 
  Inland Jackson. In southeast Texas, Austin, Brazoria Islands, 
  Coastal Brazoria, Coastal Matagorda, Colorado, Fort Bend, Inland 
  Brazoria, Inland Harris, Inland Matagorda, Matagorda Islands, 
  Waller and Wharton.

* Through Sunday morning

* Another round of showers and thunderstorms with moderate to heavy 
  rain were ongoing early this morning. Rainfall totals of 2 to 8 
  inches have already fallen, yesterday. With this new round of 
  precipitation, additional rainfall accumulations of 1 to 3 inches 
  will be possible today. Storms may weaken or depart the area by 
  late afternoon but more storms are expected this evening.

* Flooding of low-lying, poorly draining areas and other vulnerable 
  locations such as easily-flooded streets are possible if they are 
  impacted by storms with heavier rainfall rates and amounts. 
  Multiple rounds of these storms would worsen the potential for 
  flooding. Where rain rates are more manageable, previously dry 
  conditions will help reduce concerns for flooding.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead to 
Flash Flooding. Flash Flooding is a very dangerous situation. You 
should monitor later forecasts and be prepared to take action should 
Flash Flood Warnings be issued.

Stay away or be swept away. River banks and culverts can become 
unstable and unsafe.

&&

$$
857 
WGUS64 KHGX 012008
FFAHGX

Flood Watch
National Weather Service Houston/Galveston TX
308 PM CDT Sat May 1 2021

TXZ163-164-176>179-195>200-210>213-226-227-235>237-335>337-436-
437-021200-
/O.CON.KHGX.FF.A.0001.000000T0000Z-210502T1200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Austin-Brazoria Islands-Brazos-Burleson-Coastal Brazoria-
Coastal Jackson-Coastal Matagorda-Colorado-Fort Bend-Grimes-
Houston-Inland Brazoria-Inland Harris-Inland Jackson-
Inland Matagorda-Madison-Matagorda Islands-Montgomery-
Northern Liberty-Polk-San Jacinto-Trinity-Walker-Waller-
Washington-Wharton-
Including the cities of Alvin, Angleton, Bay City, Bellville, 
Brenham, Brookshire, Bryan, Caldwell, Cleveland, Clute, 
Coldspring, College Station, Columbus, Conroe, Corrigan, 
Crockett, Dayton, Eagle Lake, Edna, El Campo, First Colony, 
Freeport, Ganado, Groveton, Hempstead, Houston, Huntsville, 
Lake Jackson, Liberty, Livingston, Madisonville, Mission Bend, 
Missouri City, Navasota, Palacios, Pearland, Pecan Grove, 
Prairie View, Rosenberg, Sealy, Shepherd, Somerville, Sugar Land,
Surfside Beach, The Woodlands, Trinity, Waller, Weimar, 
and Wharton
308 PM CDT Sat May 1 2021

...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH SUNDAY MORNING...

The Flash Flood Watch continues for

* Portions of south central Texas and southeast Texas... 
  including the following counties...in south central Texas... 
  Coastal Jackson and Inland Jackson. In southeast Texas... 
  Austin...Brazoria Islands...Brazos...Burleson...Coastal 
  Brazoria...Coastal Matagorda...Colorado...Fort Bend...Grimes...
   Houston...Inland Brazoria...Inland Harris...Inland 
  Matagorda... Madison...Matagorda Islands...Montgomery...
  Northern Liberty... Polk...San Jacinto...Trinity...Walker...
  Waller...Washington and Wharton. 

* Through Sunday morning

* Another round of rain and embedded thunderstorms will be moving
  into the region from the west late this afternoon through the
  overnight hours. Rainfall totals of 4 to 10 inches have already
  fallen across parts of the region in the past 48 hours. The
  ground is saturated. Additional rainfall, especially heavy rain
  in a short time period, will quickly runoff and cause flooding.
  Some rivers, streams and creeks are near or above flood stage. 
  Expect additional rises with any moderate to heavy rainfall. 
  Precipitation should taper off late tonight and Sunday morning.

  PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead
to Flash Flooding. Flash Flooding is a very dangerous situation.
You should monitor later forecasts and be prepared to take action
should Flash Flood Warnings be issued.

Stay away or be swept away. River banks and culverts can become
unstable and unsafe.

&&

$$
223 
WGUS64 KHGX 020951
FFAHGX

Flood Watch
National Weather Service Houston/Galveston TX
451 AM CDT Sun May 2 2021

TXZ163-164-176>179-195>200-210>213-226-227-235>237-335>337-436-437-
021100-
/O.CAN.KHGX.FF.A.0001.000000T0000Z-210502T1200Z/
Houston-Trinity-Madison-Walker-San Jacinto-Polk-Burleson-Brazos-
Washington-Grimes-Montgomery-Northern Liberty-Colorado-Austin-Waller-
Inland Harris-Wharton-Fort Bend-Inland Jackson-Inland Matagorda-
Inland Brazoria-Coastal Jackson-Coastal Matagorda-Coastal Brazoria-
Matagorda Islands-Brazoria Islands-
Including the cities of Brookshire, Pearland, Caldwell, Liberty, The 
Woodlands, Coldspring, Bellville, Bay City, Trinity, Shepherd, 
Columbus, Sugar Land, College Station, Hempstead, Dayton, 
Huntsville, Crockett, Wharton, Conroe, Missouri City, Pecan Grove, 
Palacios, Bryan, Lake Jackson, Surfside Beach, Freeport, First 
Colony, Clute, Navasota, Livingston, Brenham, Waller, Eagle Lake, 
Houston, Prairie View, Groveton, Sealy, Rosenberg, Edna, Alvin, 
Ganado, Corrigan, El Campo, Mission Bend, Cleveland, Angleton, 
Somerville, Weimar, and Madisonville
451 AM CDT Sun May 2 2021

...FLASH FLOOD WATCH IS CANCELLED...

The Flash Flood Watch for portions of south central Texas and 
southeast Texas, including the following areas, in south central 
Texas, Coastal Jackson and Inland Jackson. In southeast Texas, 
Austin, Brazoria Islands, Brazos, Burleson, Coastal Brazoria, 
Coastal Matagorda, Colorado, Fort Bend, Grimes, Houston, Inland 
Brazoria, Inland Harris, Inland Matagorda, Madison, Matagorda 
Islands, Montgomery, Northern Liberty, Polk, San Jacinto, Trinity, 
Walker, Waller, Washington and Wharton has been cancelled.

The Flash Flood Watch is cancelled. Flash Flooding is no longer 
expected to pose a threat. Please continue to heed remaining road 
closures and do not attempt to drive through flooded roadways.


$$

kp

What forecasters said that day

The local office's own words before this flash flood watch went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Houston/Galveston, TX wrote its last area forecast discussion before this flash flood watch went out at Apr 29, 6:49 PM CDT, 2 hours 44 minutes earlier.

Area forecast discussion, Apr 29, 6:49 PM CDT, 2 hours 44 minutes before
Area Forecast Discussion
National Weather Service Houston/Galveston TX
649 PM CDT Thu Apr 29 2021

.AVIATION [00Z TAF Issuance]...

A somewhat tricky aviation forecast across southeast Texas. Spotty
showers and VCSH for most of our TAF sites, but shower activity is
expected to increase as a cold front approaches our area tonight.
Put in TSRA for some TAF sites starting at approximately 07-09Z
where there was higher confidence where thunderstorms would form.
Kept in VCTS everywhere else where confidence was lower, but will
amend as necessary. Currently, MVFR ceilings will drop to IFR
overnight.  KBL

&&

.PREV DISCUSSION /Issued 306 PM CDT Thu Apr 29 2021/...

.SHORT TERM [Through Friday Night]...

A complicated and messy pattern shaping up for SE TX over the next
couple of days as a weak cold front crosses the area tonight and
an upper level low over northern Mexico meanders across the state
through the weekend. PW values are progged to exceed 2.00 inches
tonight through Friday night and this seems to be verifying well
based on satellite derived values. The NAM and GFS show upper
level winds splitting over the region late tonight and Friday
while the EC shows the best upper level divergence over Central
Texas. As the weak front slowly crosses SE TX and encounters the
warm, moist air mass over SE TX, it seems reasonable that there
will be an expansion of showers and thunderstorms over the region.
SPC still has the NE half of the region outlooked in Marginal Risk
but extensive cloud cover has limited heating and CAPE values
remain modest and lapse rates not looking all that impressive.
Could still get an occasional strong storm later tonight that
could produce brief gusty winds but the primary threat late
tonight and Friday will be the potential for heavy rain.

Where will the heavy rain fall? It's not entirely clear but based
on the position of the front and upper level divergence, feel the
threat for heavy rain will focus over the NNW part of the region
tonight and expand to the WSW on Friday. There should be some
training of storms so some areas will receive heavy rain. At this
time, 1-2 inches of rain is expected on Friday with locally
higher amounts. Have added locally heavy rain to the wx grids
beginning after 06z tonight but will forego a Flash Flood Watch
for now based on dry antecedent conditions. Meso-scale influences
will ultimately determine where the heaviest rain will fall and
some of the short term guidance (HiRes ARW, HRRR and HREF) show
some 3 to 6 inch rainfall totals by Friday evening. The cold
front will struggle to reach the coast and will likely be pulled
back inland in response to developing low pressure near the middle
TX coast. Coastal areas could remain significantly drier than the
rest of SE TX if the front stalls inland. Will it continue to
rain Friday night? At this time, it appears that the area will be
pretty worked over and much of the available moisture will be
pulled westward toward the upper level low. The best upper level
divergence also favors the WNW portion of the CWA. Will maintain
high rain chances out west but taper PoPs sharply lower to the
east.

MinT values tonight will remain warm due to clouds and onshore
winds. MaxT values on Friday won't show much warming due to
anticipated rainfall and cloud cover with max values probably
remaining in the 70's. A little cooler Friday night north of the
retreating front but it'll remain warm and humid south of the
front. 43

.LONG TERM [Saturday through Thursday]...

Confidence is increasing for an ongoing active weather pattern
throughout the upcoming weekend. Saturday, a surface coastal trough
situated along the TX coastal area and associated low pressure over
Southern TX will continue to enhance the transport of low level
moisture from the Gulf. PWs will likely range between 1.8 to 2.1
inches. Along the upper levels, a shortwave moving eastward
northeastward along the base of a strong upper cut-off low that is
located roughly over NE Mexico and Western TX is progged to move
over SE Texas Saturday morning. Moreover, due to the position of the
cut-off low, an area of diffluence aloft could potentially set up
over much of the eastern half of TX Saturday morning and afternoon.
Thus, it seems that these features will favor ongoing shower and
thunderstorm activity for much of the day Saturday. SPC Day 3
Outlook has placed much of the northern two thirds of the CWA under
a Marginal Risk for Severe Thunderstorms. Now, even though there are
many factors that could contribute to the development of strong
showers and thunderstorms, timing and positioning of both the upper
and coastal low differ slightly in the models and thus will make it
tough to pin point exactly where and when the strongest activity
will occur. The general picture at this time is for showers and
thunderstorms along the western half of the CWA Saturday morning
gradually transitioning into the central and eastern portions of the
CWA Saturday night into Sunday as the upper low moves east or
northeast into Eastern TX. With locally heavy rainfall, there is
also the potential for minor flooding, especially along areas where
soils have been saturated by previous rainfall on Thursday and
Friday or area rain continues to entrain for long periods of time.
The WPC ERO Day 3 (Saturday) continues a Marginal Risk for Excessive
Rainfall. Activity will ebb Sunday night as all weather features
finally shift to our east and/or northeast.

Another chance for showers and thunderstorms may occur Tuesday
evening into Wednesday with the next cold front. Have kept slight
chances of showers and thunderstorms at this time.

24

.MARINE...

Although winds have relaxed, the long period swell continues over
the Gulf waters and should keep seas elevated particularly over the
offshore waters through late this afternoon or evening. The SCA over
the nearshore waters has been lowered to a SCEC, but the SCA will
continue for the offshore waters. The High Risk for Rip Currents
also remains in effect through this evening. A cold front
scheduled to move across SE TX later today into Friday morning.
Then, a strong coastal surface low will develop along the TX
coasts Saturday with a strong onshore flow. A brief wind shift to
the west is expected Sunday in the wake of the sfc low but winds
will become onshore again by Sunday night. A period of strong
storms will be possible Saturday and Saturday night with precip
winding down on Sunday. Stronger storms will be capable of
producing brief periods of heavy to torrential rainfall, strong
gusty winds, frequent lightning and elevated seas. Moderate to
occasionally strong onshore winds will develop Monday into Tuesday
ahead of another cold front that is expected to cross the coastal
waters Tuesday night. Seas will remain elevated through mid week.

24

&&

.PRELIMINARY POINT TEMPS/POPS...

College Station (CLL)  70  77  66  77  65 /  80  80  60  70  60
Houston (IAH)          72  78  67  77  68 /  70  80  30  60  60
Galveston (GLS)        73  78  71  78  71 /  40  50  20  50  60

&&

.HGX WATCHES/WARNINGS/ADVISORIES...

TX...High Rip Current Risk until 7 PM CDT this evening for the
     following zones: Bolivar Peninsula...Brazoria
     Islands...Galveston Island...Matagorda Islands.

GM...SMALL CRAFT SHOULD EXERCISE CAUTION until 11 PM CDT this evening
     for the following zones: Coastal waters from Freeport to
     Matagorda Ship Channel TX out 20 NM...Coastal waters from
     High Island to Freeport TX out 20 NM.

     Small Craft Advisory until 11 PM CDT this evening for the
     following zones: Waters from Freeport to Matagorda Ship
     Channel TX from 20 to 60 NM...Waters from High Island to
     Freeport TX from 20 to 60 NM.

&&

The office that day

Everything else NWS Houston/Galveston, TX issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 30, 3:17 AM CDTAreal Flood AdvisoryHGXHouston, Madison, Trinity, Walker3 hr
Apr 30, 3:38 AM CDTCoastal Flood AdvisoryHGXBrazoria, Galveston, Matagorda15 hr
Apr 30, 3:38 AM CDTRip Current StatementHGXBrazoria, Galveston, Matagorda15 hr
Apr 30, 3:49 AM CDTSmall Craft AdvisoryHGX17 hr
Apr 30, 4:05 AM CDTSpecial Weather StatementHGXMatagorda40 min
Apr 30, 5:06 AM CDTSpecial Weather StatementHGXLiberty, Polk, San Jacinto39 min
Apr 30, 5:08 AM CDTSpecial Weather StatementHGXColorado, Wharton52 min
Apr 30, 5:40 AM CDTAreal Flood AdvisoryHGXAustin, Grimes, Harris, Montgomery, Waller, Washington3 hr
Apr 30, 6:01 AM CDTFlash Flood WarningHGXGrimes, Harris, Montgomery, San Jacinto, Walker, Waller5 hr
Apr 30, 7:05 AM CDTAreal Flood AdvisoryHGXLiberty, Montgomery, Polk, San Jacinto3 hr
Apr 30, 8:19 AM CDTAreal Flood AdvisoryHGXChambers, Harris, Liberty, Montgomery116 min
Apr 30, 9:12 AM CDTAreal Flood AdvisoryHGXHarris, Liberty, Montgomery, Polk, San Jacinto2 hr
Apr 30, 9:53 AM CDTAreal Flood AdvisoryHGXAustin, Harris, Waller, Washington112 min
Apr 30, 11:04 AM CDTAreal Flood AdvisoryHGXAustin, Brazos, Burleson, Grimes, Harris, Houston and 9 more116 min

Nearby

Flash Flood Watches in Texas, 2021Every flash flood watch in 2021

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.