Alert archive / Texas / Flash Flood Watches in 2021
Flash Flood Watch 4, NWS Houston/Galveston, TX
NWS Houston/Galveston, TX issued this flash flood watch at May 17, 2021, 1:41 PM CDT for 23 counties in Texas. It was in force for 68 hr.
The area
The counties it named.
The facts
- Issued
- May 17, 2021, 1:41 PM CDT (18:41 UTC)
- Expired
- May 20, 2021, 9:34 AM CDT
- In force
- 68 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 18:42 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 12:00Z, 6.7 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.
- Mixed-layer CAPE
- 626 J/kg
- Mixed-layer CIN
- -14 J/kg
- Mixed-layer LCL
- 699 m above ground
- 0-6 km bulk shear
- 32 kt
- 0-1 km storm-relative helicity
- 207 m²/s²
- 0-3 km storm-relative helicity
- 314 m²/s²
- Significant tornado parameter
- 0.7
- Supercell composite
- 10.3
The text
As transmitted.
655 WGUS64 KHGX 171841 FFAHGX URGENT - IMMEDIATE BROADCAST REQUESTED Flood Watch National Weather Service Houston/Galveston TX 141 PM CDT Mon May 17 2021 .A slow moving upper level trough of low pressure will bring periods of showers and thunderstorms to the region through the end of the week. TXZ163-164-176>179-195>200-210>214-226-227-235>238-300-313-335>338- 436>439-180645- /O.NEW.KHGX.FF.A.0004.210517T1841Z-210520T1200Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Houston-Trinity-Madison-Walker-San Jacinto-Polk-Burleson-Brazos- Washington-Grimes-Montgomery-Northern Liberty-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, Caldwell, Stowell, Liberty, The Woodlands, Dickinson, Devers, Anahuac, Coldspring, Bellville, Bay City, Trinity, Shepherd, Columbus, Sugar Land, College Station, Surfside Beach, Hempstead, Dayton, Huntsville, Baytown, Crockett, Wharton, Conroe, Missouri City, Pecan Grove, Palacios, League City, La Marque, Bryan, Lake Jackson, Mont Belvieu, Old River-Winfree, Pasadena, Freeport, First Colony, Clute, Navasota, Livingston, Texas City, Brenham, Waller, Eagle Lake, Galveston, Houston, Prairie View, Groveton, Sealy, Rosenberg, Friendswood, Winnie, Alvin, Ganado, Corrigan, El Campo, Mission Bend, Edna, Cleveland, Angleton, Somerville, Weimar, and Madisonville 141 PM CDT Mon May 17 2021 ...FLASH FLOOD WATCH IN EFFECT THROUGH THURSDAY 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, Brazos, Burleson, Chambers, Coastal Brazoria, Coastal Galveston, Coastal Harris, Coastal Matagorda, Colorado, Fort Bend, Galveston Island, Grimes, Houston, Inland Brazoria, Inland Galveston, Inland Harris, Inland Matagorda, Madison, Matagorda Islands, Montgomery, Northern Liberty, Polk, San Jacinto, Southern Liberty, Trinity, Walker, Waller, Washington and Wharton. * Through Thursday morning * Heavy rain will focus on a slow moving outflow boundary this afternoon into this evening and produce 1 to 3 inches of rain with locally higher amounts possible. An upper level disturbance will bring additional showers and thunderstorms on Tuesday with another 1 to 3 inches of rain with again locally higher totals. A stronger upper level disturbance will bring yet another round of heavy rain Wednesday into Thursday with additional rainfall totals of 2 to 4 inches of rain with again locally higher totals possible. Storm total rainfall by Thursday morning will average between 4 and 8 inches with isolated totals possibly exceeding ten inches. The flood threat will be strongly dependent on where the rain falls and how quickly it falls. 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. && $$ CR
10 follow-up statements
411 WGUS64 KHGX 180308 FFAHGX Flood Watch National Weather Service Houston/Galveston TX 1008 PM CDT Mon May 17 2021 TXZ163-164-176>179-195>200-210>214-226-227-235>238-300-313-335>338- 436>439-181115- /O.CON.KHGX.FF.A.0004.000000T0000Z-210520T1200Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Houston-Trinity-Madison-Walker-San Jacinto-Polk-Burleson-Brazos- Washington-Grimes-Montgomery-Northern Liberty-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, Caldwell, Stowell, Liberty, The Woodlands, Dickinson, Devers, Anahuac, Coldspring, Bellville, Bay City, Trinity, Shepherd, Columbus, Sugar Land, College Station, Surfside Beach, Hempstead, Dayton, Huntsville, Baytown, Crockett, Wharton, Conroe, Missouri City, Pecan Grove, Palacios, League City, La Marque, Bryan, Lake Jackson, Mont Belvieu, Old River-Winfree, Pasadena, Freeport, First Colony, Clute, Navasota, Livingston, Texas City, Brenham, Waller, Eagle Lake, Galveston, Houston, Prairie View, Groveton, Sealy, Rosenberg, Friendswood, Winnie, Alvin, Ganado, Corrigan, El Campo, Mission Bend, Edna, Cleveland, Angleton, Somerville, Weimar, and Madisonville 1008 PM CDT Mon May 17 2021 ...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH THURSDAY 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, Brazos, Burleson, Chambers, Coastal Brazoria, Coastal Galveston, Coastal Harris, Coastal Matagorda, Colorado, Fort Bend, Galveston Island, Grimes, Houston, Inland Brazoria, Inland Galveston, Inland Harris, Inland Matagorda, Madison, Matagorda Islands, Montgomery, Northern Liberty, Polk, San Jacinto, Southern Liberty, Trinity, Walker, Waller, Washington and Wharton. * Through Thursday morning * A slow moving line of thunderstorms moved through the area on Monday producing generally 1 to 4 inches of rain across the area with localized areas of 6 to 8 inches across Liberty, eastern Montgomery, and northeastern Harris County. A lull in the precipitation will continue tonight, but the chance for heavy rainfall returns Tuesday morning as an upper level disturbance moves through the area. An additional 1 to 3 inches of rain with locally higher totals will be possible on Tuesday. A stronger upper level disturbance will bring yet another round of heavy rain Wednesday into Thursday with additional rainfall totals of 2 to 4 inches of rain with again locally higher totals possible. Storm total rainfall by Thursday morning will average between 4 and 8 inches with isolated totals possibly exceeding 10 inches. The flood threat will be strongly dependent on where the rain falls and how quickly it falls. 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. && $$
118 WGUS64 KHGX 180744 FFAHGX Flood Watch National Weather Service Houston/Galveston TX 244 AM CDT Tue May 18 2021 TXZ163-164-176>179-195>200-210>214-226-227-235>238-300-313- 335>338-436>439-182300- /O.CON.KHGX.FF.A.0004.000000T0000Z-210520T1200Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Austin-Bolivar Peninsula-Brazoria Islands-Brazos-Burleson- Chambers-Coastal Brazoria-Coastal Galveston-Coastal Harris- Coastal Jackson-Coastal Matagorda-Colorado-Fort Bend- Galveston Island-Grimes-Houston-Inland Brazoria-Inland Galveston- Inland Harris-Inland Jackson-Inland Matagorda-Madison- Matagorda Islands-Montgomery-Northern Liberty-Polk-San Jacinto- Southern Liberty-Trinity-Walker-Waller-Washington-Wharton- Including the cities of Alvin, Anahuac, Angleton, Bay City, Baytown, Bellville, Brenham, Brookshire, Bryan, Caldwell, Cleveland, Clute, Coldspring, College Station, Columbus, Conroe, Corrigan, Crockett, Dayton, Devers, Dickinson, Eagle Lake, Edna, El Campo, First Colony, Freeport, Friendswood, Galveston, Ganado, Groveton, Hempstead, Houston, Huntsville, La Marque, Lake Jackson, League City, Liberty, Livingston, Madisonville, Mission Bend, Missouri City, Mont Belvieu, Navasota, Old River-Winfree, Palacios, Pasadena, Pearland, Pecan Grove, Prairie View, Rosenberg, Sealy, Shepherd, Somerville, Stowell, Sugar Land, Surfside Beach, Texas City, The Woodlands, Trinity, Waller, Weimar, Wharton, and Winnie 244 AM CDT Tue May 18 2021 ...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH THURSDAY 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...Bolivar Peninsula...Brazoria Islands...Brazos... Burleson...Chambers...Coastal Brazoria...Coastal Galveston... Coastal Harris...Coastal Matagorda...Colorado...Fort Bend... Galveston Island...Grimes...Houston...Inland Brazoria...Inland Galveston...Inland Harris...Inland Matagorda...Madison... Matagorda Islands...Montgomery...Northern Liberty...Polk...San Jacinto...Southern Liberty...Trinity...Walker...Waller... Washington and Wharton. * Through Thursday morning * A slow moving line of thunderstorms moved through the area on Monday producing generally 1 to 4 inches of rain across the area with localized areas of 6 to 8 inches across Liberty, eastern Montgomery, and northeastern Harris County. A lull in the precipitation occurred overnight, but the chance for heavy rainfall returns this morning as an upper level disturbance moves through the area. An additional 1 to 3 inches of rain with locally higher totals will be possible today. A stronger upper level disturbance will bring yet another round of heavy rain Wednesday into Thursday with additional rainfall totals of 2 to 4 inches of rain with again locally higher totals possible. Storm total rainfall by Thursday morning will average between 4 and 8 inches with isolated totals possibly exceeding 10 inches. The flood threat will be strongly dependent on where the rain falls and how quickly it falls. 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. && $$
283 WGUS64 KHGX 181420 FFAHGX Flood Watch National Weather Service Houston/Galveston TX 920 AM CDT Tue May 18 2021 TXZ163-164-176>179-195>200-210>214-226-227-235>238-300-313-335>338- 436>439-191100- /O.CON.KHGX.FF.A.0004.000000T0000Z-210520T1200Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Houston-Trinity-Madison-Walker-San Jacinto-Polk-Burleson-Brazos- Washington-Grimes-Montgomery-Northern Liberty-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, Caldwell, Stowell, Liberty, The Woodlands, Dickinson, Devers, Anahuac, Coldspring, Bellville, Bay City, Trinity, Shepherd, Columbus, Sugar Land, College Station, Surfside Beach, Hempstead, Dayton, Huntsville, Baytown, Crockett, Wharton, Conroe, Missouri City, Pecan Grove, Palacios, League City, La Marque, Bryan, Lake Jackson, Mont Belvieu, Old River-Winfree, Pasadena, Freeport, First Colony, Clute, Navasota, Livingston, Texas City, Brenham, Waller, Eagle Lake, Galveston, Houston, Prairie View, Groveton, Sealy, Rosenberg, Friendswood, Winnie, Alvin, Ganado, Corrigan, El Campo, Mission Bend, Edna, Cleveland, Angleton, Somerville, Weimar, and Madisonville 920 AM CDT Tue May 18 2021 ...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH THURSDAY 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, Brazos, Burleson, Chambers, Coastal Brazoria, Coastal Galveston, Coastal Harris, Coastal Matagorda, Colorado, Fort Bend, Galveston Island, Grimes, Houston, Inland Brazoria, Inland Galveston, Inland Harris, Inland Matagorda, Madison, Matagorda Islands, Montgomery, Northern Liberty, Polk, San Jacinto, Southern Liberty, Trinity, Walker, Waller, Washington and Wharton. * Through Thursday morning * A slow moving line of thunderstorms moved through the area on Monday producing generally 1 to 4 inches of rain across the area with localized areas of 6 to 8 inches across Liberty, eastern Montgomery, and northeastern Harris County. A lull in the precipitation occurred overnight, but the chance for heavy rainfall will return this afternoon as an upper level disturbance moves through the area. An additional 1 to 3 inches of rain with locally higher totals will be possible today. A stronger upper level disturbance will bring yet another round of heavy rain Wednesday into Thursday with additional rainfall totals of 2 to 4 inches of rain with again locally higher totals possible. Storm total rainfall by Thursday morning will average between 4 and 8 inches with isolated totals possibly exceeding 10 inches. The flood threat will be strongly dependent on where the rain falls and how quickly it falls. 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. && $$ CR
548 WGUS64 KHGX 182032 FFAHGX Flood Watch National Weather Service Houston/Galveston TX 332 PM CDT Tue May 18 2021 TXZ163-164-176>179-195>200-210>214-226-227-235>238-300-313-335>338- 436>439-191215- /O.CON.KHGX.FF.A.0004.000000T0000Z-210520T1200Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Houston-Trinity-Madison-Walker-San Jacinto-Polk-Burleson-Brazos- Washington-Grimes-Montgomery-Northern Liberty-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, Caldwell, Stowell, Liberty, The Woodlands, Dickinson, Devers, Anahuac, Coldspring, Bellville, Bay City, Trinity, Shepherd, Columbus, Sugar Land, College Station, Surfside Beach, Hempstead, Dayton, Huntsville, Baytown, Crockett, Wharton, Conroe, Missouri City, Pecan Grove, Palacios, League City, La Marque, Bryan, Lake Jackson, Mont Belvieu, Old River-Winfree, Pasadena, Freeport, First Colony, Clute, Navasota, Livingston, Texas City, Brenham, Waller, Eagle Lake, Galveston, Houston, Prairie View, Groveton, Sealy, Rosenberg, Friendswood, Winnie, Alvin, Ganado, Corrigan, El Campo, Mission Bend, Edna, Cleveland, Angleton, Somerville, Weimar, and Madisonville 332 PM CDT Tue May 18 2021 ...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH THURSDAY 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, Brazos, Burleson, Chambers, Coastal Brazoria, Coastal Galveston, Coastal Harris, Coastal Matagorda, Colorado, Fort Bend, Galveston Island, Grimes, Houston, Inland Brazoria, Inland Galveston, Inland Harris, Inland Matagorda, Madison, Matagorda Islands, Montgomery, Northern Liberty, Polk, San Jacinto, Southern Liberty, Trinity, Walker, Waller, Washington and Wharton. * Through Thursday morning * An upper level disturbance over Central Texas and an outflow boundary will move into Southeast Texas this evening. An additional 1 to 3 inches of rain with locally higher totals will be possible tonight. A stronger upper level disturbance will bring yet another round of heavy rain on Wednesday into Thursday with additional rainfall totals of 2 to 4 inches of rain with again locally higher totals possible. Storm total rainfall by Thursday morning will average between 4 and 8 inches with isolated totals possibly exceeding 10 inches. The flood threat will be strongly dependent on where the rain falls and how quickly it falls. 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. && $$ CR
852 WGUS64 KHGX 190908 FFAHGX URGENT - IMMEDIATE BROADCAST REQUESTED Flood Watch National Weather Service Houston/Galveston TX 408 AM CDT Wed May 19 2021 TXZ163-164-176>179-195>200-210>214-226-227-235>238-300-313- 335>338-436>439-191715- /O.EXT.KHGX.FF.A.0004.000000T0000Z-210520T1800Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Austin-Bolivar Peninsula-Brazoria Islands-Brazos-Burleson- Chambers-Coastal Brazoria-Coastal Galveston-Coastal Harris- Coastal Jackson-Coastal Matagorda-Colorado-Fort Bend- Galveston Island-Grimes-Houston-Inland Brazoria-Inland Galveston- Inland Harris-Inland Jackson-Inland Matagorda-Madison- Matagorda Islands-Montgomery-Northern Liberty-Polk-San Jacinto- Southern Liberty-Trinity-Walker-Waller-Washington-Wharton- Including the cities of Alvin, Anahuac, Angleton, Bay City, Baytown, Bellville, Brenham, Brookshire, Bryan, Caldwell, Cleveland, Clute, Coldspring, College Station, Columbus, Conroe, Corrigan, Crockett, Dayton, Devers, Dickinson, Eagle Lake, Edna, El Campo, First Colony, Freeport, Friendswood, Galveston, Ganado, Groveton, Hempstead, Houston, Huntsville, La Marque, Lake Jackson, League City, Liberty, Livingston, Madisonville, Mission Bend, Missouri City, Mont Belvieu, Navasota, Old River-Winfree, Palacios, Pasadena, Pearland, Pecan Grove, Prairie View, Rosenberg, Sealy, Shepherd, Somerville, Stowell, Sugar Land, Surfside Beach, Texas City, The Woodlands, Trinity, Waller, Weimar, Wharton, and Winnie 408 AM CDT Wed May 19 2021 ...FLASH FLOOD WATCH NOW IN EFFECT THROUGH THURSDAY MORNING... The Flash Flood Watch is now in effect 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...Bolivar Peninsula...Brazoria Islands...Brazos... Burleson...Chambers...Coastal Brazoria...Coastal Galveston... Coastal Harris...Coastal Matagorda...Colorado...Fort Bend... Galveston Island...Grimes...Houston...Inland Brazoria...Inland Galveston...Inland Harris...Inland Matagorda...Madison... Matagorda Islands...Montgomery...Northern Liberty...Polk...San Jacinto...Southern Liberty...Trinity...Walker...Waller... Washington and Wharton. * Through Thursday morning * A couple more rounds of showers and thunderstorms can be expected across parts of Southeast Texas through Thursday morning. Rainfall totals are expected to average 2 to 4 inches with locally higher amounts possible, and these could happen in a very short period of time. If any heavy rain falls on already saturated grounds, flash flooding can be expected. Rainfall totals for the week with this event are still expected to average 4 and 8 inches with isolated totals possibly exceeding 10 inches. 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. && $$
802 WGUS64 KHGX 191508 FFAHGX Flood Watch National Weather Service Houston/Galveston TX 1008 AM CDT Wed May 19 2021 TXZ163-164-176>179-195>200-210>214-226-227-235>238-300-313- 335>338-436>439-192315- /O.CON.KHGX.FF.A.0004.000000T0000Z-210520T1800Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Austin-Bolivar Peninsula-Brazoria Islands-Brazos-Burleson- Chambers-Coastal Brazoria-Coastal Galveston-Coastal Harris- Coastal Jackson-Coastal Matagorda-Colorado-Fort Bend- Galveston Island-Grimes-Houston-Inland Brazoria-Inland Galveston- Inland Harris-Inland Jackson-Inland Matagorda-Madison- Matagorda Islands-Montgomery-Northern Liberty-Polk-San Jacinto- Southern Liberty-Trinity-Walker-Waller-Washington-Wharton- Including the cities of Alvin, Anahuac, Angleton, Bay City, Baytown, Bellville, Brenham, Brookshire, Bryan, Caldwell, Cleveland, Clute, Coldspring, College Station, Columbus, Conroe, Corrigan, Crockett, Dayton, Devers, Dickinson, Eagle Lake, Edna, El Campo, First Colony, Freeport, Friendswood, Galveston, Ganado, Groveton, Hempstead, Houston, Huntsville, La Marque, Lake Jackson, League City, Liberty, Livingston, Madisonville, Mission Bend, Missouri City, Mont Belvieu, Navasota, Old River-Winfree, Palacios, Pasadena, Pearland, Pecan Grove, Prairie View, Rosenberg, Sealy, Shepherd, Somerville, Stowell, Sugar Land, Surfside Beach, Texas City, The Woodlands, Trinity, Waller, Weimar, Wharton, and Winnie 1008 AM CDT Wed May 19 2021 ...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH THURSDAY AFTERNOON... 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...Bolivar Peninsula...Brazoria Islands...Brazos... Burleson...Chambers...Coastal Brazoria...Coastal Galveston... Coastal Harris...Coastal Matagorda...Colorado...Fort Bend... Galveston Island...Grimes...Houston...Inland Brazoria...Inland Galveston...Inland Harris...Inland Matagorda...Madison... Matagorda Islands...Montgomery...Northern Liberty...Polk...San Jacinto...Southern Liberty...Trinity...Walker...Waller... Washington and Wharton. * Through Thursday afternoon * Light to moderate rain continues across southern parts of the area this morning in the wake of last nights storms. Expect another disturbance to move into the area from the west and southwest later today. The heaviest rain with this particular system should mostly be focused along the coast and offshore, though some scattered heavier cells remain a possibility up to the Interstate 45 or Highway 105 corridor. The ground is saturated, and although rainfall amounts today might not be as high as yesterday, any additional moderate to heavy rain falling in a short time period will lead to rapid runoff and the threat of flash 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. && $$
254 WGUS64 KHGX 192039 FFAHGX Flood Watch National Weather Service Houston/Galveston TX 339 PM CDT Wed May 19 2021 TXZ163-164-176>179-195>200-210>214-226-227-235>238-300-313- 335>338-436>439-201200- /O.CON.KHGX.FF.A.0004.000000T0000Z-210520T1800Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Austin-Bolivar Peninsula-Brazoria Islands-Brazos-Burleson- Chambers-Coastal Brazoria-Coastal Galveston-Coastal Harris- Coastal Jackson-Coastal Matagorda-Colorado-Fort Bend- Galveston Island-Grimes-Houston-Inland Brazoria-Inland Galveston- Inland Harris-Inland Jackson-Inland Matagorda-Madison- Matagorda Islands-Montgomery-Northern Liberty-Polk-San Jacinto- Southern Liberty-Trinity-Walker-Waller-Washington-Wharton- Including the cities of Alvin, Anahuac, Angleton, Bay City, Baytown, Bellville, Brenham, Brookshire, Bryan, Caldwell, Cleveland, Clute, Coldspring, College Station, Columbus, Conroe, Corrigan, Crockett, Dayton, Devers, Dickinson, Eagle Lake, Edna, El Campo, First Colony, Freeport, Friendswood, Galveston, Ganado, Groveton, Hempstead, Houston, Huntsville, La Marque, Lake Jackson, League City, Liberty, Livingston, Madisonville, Mission Bend, Missouri City, Mont Belvieu, Navasota, Old River-Winfree, Palacios, Pasadena, Pearland, Pecan Grove, Prairie View, Rosenberg, Sealy, Shepherd, Somerville, Stowell, Sugar Land, Surfside Beach, Texas City, The Woodlands, Trinity, Waller, Weimar, Wharton, and Winnie 339 PM CDT Wed May 19 2021 ...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH THURSDAY AFTERNOON... 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...Bolivar Peninsula...Brazoria Islands...Brazos... Burleson...Chambers...Coastal Brazoria...Coastal Galveston... Coastal Harris...Coastal Matagorda...Colorado...Fort Bend... Galveston Island...Grimes...Houston...Inland Brazoria...Inland Galveston...Inland Harris...Inland Matagorda...Madison... Matagorda Islands...Montgomery...Northern Liberty...Polk...San Jacinto...Southern Liberty...Trinity...Walker...Waller... Washington and Wharton. * Through Thursday afternoon * Light to occasional moderate rain continues across portions of the area and will continue into the evening and overnight hours. Assuming the rain rates remain on the low end as forecast, the overall flash flood threat appears to be trending downward and toward a more localized issue versus a widespread threat. That said, area grounds are saturated and creeks and rivers are elevated. Any location that sees brief heavier activity will be prone to rapid runoff and flooding. Locations south and west of a Brenham to Galveston line have seen the highest accumulations the past couple days, and with the exception of ongoing river flooding elsewhere, will be the more prone locations for additional flooding due to runoff. We will continue to evaluate the situation and there is a possibility the Watch is reconfigured and/or cancelled for parts of the area later tonight. 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. && $$
611 WGUS64 KHGX 200310 FFAHGX Flood Watch National Weather Service Houston/Galveston TX 1010 PM CDT Wed May 19 2021 TXZ163-164-176-177-195>198-210-211-200415- /O.CAN.KHGX.FF.A.0004.000000T0000Z-210520T1800Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Austin-Brazos-Burleson-Colorado-Grimes-Houston-Madison-Trinity- Walker-Washington- Including the cities of Bellville, Brenham, Bryan, Caldwell, College Station, Columbus, Crockett, Eagle Lake, Groveton, Huntsville, Madisonville, Navasota, Sealy, Somerville, Trinity, and Weimar 1010 PM CDT Wed May 19 2021 ...FLASH FLOOD WATCH IS CANCELLED... The Flash Flood Watch for a portion of southeast Texas has been cancelled. $$ TXZ178-179-199-200-212>214-226-227-235>238-300-313-335>338- 436>439-201115- /O.CON.KHGX.FF.A.0004.000000T0000Z-210520T1800Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Bolivar Peninsula-Brazoria Islands-Chambers-Coastal Brazoria- Coastal Galveston-Coastal Harris-Coastal Jackson- Coastal Matagorda-Fort Bend-Galveston Island-Inland Brazoria- Inland Galveston-Inland Harris-Inland Jackson-Inland Matagorda- Matagorda Islands-Montgomery-Northern Liberty-Polk-San Jacinto- Southern Liberty-Waller-Wharton- Including the cities of Alvin, Anahuac, Angleton, Bay City, Baytown, Brookshire, Cleveland, Clute, Coldspring, Conroe, Corrigan, Dayton, Devers, Dickinson, Edna, El Campo, First Colony, Freeport, Friendswood, Galveston, Ganado, Hempstead, Houston, La Marque, Lake Jackson, League City, Liberty, Livingston, Mission Bend, Missouri City, Mont Belvieu, Old River-Winfree, Palacios, Pasadena, Pearland, Pecan Grove, Prairie View, Rosenberg, Shepherd, Stowell, Sugar Land, Surfside Beach, Texas City, The Woodlands, Waller, Wharton, and Winnie 1010 PM CDT Wed May 19 2021 ...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH THURSDAY AFTERNOON... 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... Bolivar Peninsula...Brazoria Islands...Chambers...Coastal Brazoria...Coastal Galveston...Coastal Harris...Coastal Matagorda...Fort Bend...Galveston Island...Inland Brazoria... Inland Galveston...Inland Harris...Inland Matagorda... Matagorda Islands...Montgomery...Northern Liberty...Polk...San Jacinto...Southern Liberty...Waller and Wharton. * Through Thursday afternoon * Spotty rainfall is expected overnight with the possibility of a more concentrated area of showers and thunderstorms from Chambers county northward through Eastern Harris...Montgomery and San Jacinto counties eastward. These storms should only bring additional rainfall totals of less than 2 inches. Scattered storms will be possible across the Watch region during the day Thursday and could bring short lived brief heavy rains. The overall flash flood threat appears to be trending downward and toward a more localized issue versus a widespread threat. That said, area grounds are saturated and creeks and rivers are elevated. Any location that sees brief heavier activity will be prone to rapid runoff and 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. && $$
874 WGUS64 KHGX 200836 FFAHGX URGENT - IMMEDIATE BROADCAST REQUESTED Flood Watch National Weather Service Houston/Galveston TX 336 AM CDT Thu May 20 2021 TXZ178-199-212-213-226-227-235>238-313-335>338-436>439-200945- /O.CAN.KHGX.FF.A.0004.000000T0000Z-210520T1800Z/ San Jacinto-Montgomery-Waller-Inland Harris-Wharton-Fort Bend-Inland Jackson-Inland Matagorda-Inland Brazoria-Inland Galveston-Coastal Harris-Coastal Jackson-Coastal Matagorda-Coastal Brazoria-Coastal Galveston-Matagorda Islands-Brazoria Islands-Galveston Island- Bolivar Peninsula- Including the cities of Brookshire, Pearland, Baytown, Texas City, The Woodlands, Dickinson, Pasadena, Coldspring, Bay City, Shepherd, Hempstead, Wharton, Conroe, Missouri City, Pecan Grove, Palacios, League City, La Marque, Lake Jackson, Surfside Beach, Freeport, First Colony, Clute, Alvin, Waller, Sugar Land, Galveston, Houston, Prairie View, Rosenberg, Friendswood, Edna, Ganado, El Campo, Mission Bend, and Angleton 336 AM CDT Thu May 20 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, Bolivar Peninsula, Brazoria Islands, Coastal Brazoria, Coastal Galveston, Coastal Harris, Coastal Matagorda, Fort Bend, Galveston Island, Inland Brazoria, Inland Galveston, Inland Harris, Inland Matagorda, Matagorda Islands, Montgomery, San Jacinto, Waller and Wharton has been cancelled. The Flood Watch is cancelled. $$ TXZ179-200-214-300-201645- /O.EXT.KHGX.FF.A.0004.000000T0000Z-210521T0000Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Polk-Northern Liberty-Chambers-Southern Liberty- Including the cities of Mont Belvieu, Dayton, Winnie, Devers, Corrigan, Liberty, Stowell, Livingston, Anahuac, Old River-Winfree, and Cleveland 336 AM CDT Thu May 20 2021 ...FLASH FLOOD WATCH NOW IN EFFECT THROUGH THIS EVENING... The Flash Flood Watch is now in effect for * A portion of southeast Texas, including the following areas, Chambers, Northern Liberty, Polk and Southern Liberty. * Through this evening * Very saturated soils remain over these counties and any additional heavy rainfall could increase the risk of flash flooding through 7 PM CDT today. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Flash Flood Watch means that conditions may develop that lead to Flash Flooding. Flash Flooding is a very dangerous situation. You should monitor later forecasts and be prepared to take action should Flash Flood Warnings be issued. && $$
268 WGUS64 KHGX 201434 FFAHGX Flood Watch National Weather Service Houston/Galveston TX 934 AM CDT Thu May 20 2021 TXZ179-200-214-300-201545- /O.CAN.KHGX.FF.A.0004.000000T0000Z-210521T0000Z/ /00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/ Chambers-Northern Liberty-Polk-Southern Liberty- Including the cities of Anahuac, Cleveland, Corrigan, Dayton, Devers, Liberty, Livingston, Mont Belvieu, Old River-Winfree, Stowell, and Winnie 934 AM CDT Thu May 20 2021 ...FLASH FLOOD WATCH IS CANCELLED... The Flash Flood Watch for a portion of southeast Texas has been cancelled. Though scattered showers and thunderstorms are possible today, the overall flash flood threat appears to be more localized in nature. $$
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 May 17, 12:12 PM CDT, 1 hour 29 minutes earlier.
Area forecast discussion, May 17, 12:12 PM CDT, 1 hour 29 minutes before
Area Forecast Discussion
National Weather Service Houston/Galveston TX
1212 PM CDT Mon May 17 2021
.AVIATION...
Another messy afternoon for aviation interests. An outflow
boundary will propagate into SE TX and stall. Convection is
expected to back build along the boundary and will likely affect
central and southern TAF sites this afternoon. Have added a TEMPO
for the Houston terminals and KSGR. Added wind gust groups as well
and there will be restrictions to vsby. The precip is expected to
wane around 23-00z and then remain quiet for the rest of the
night. A weak upper level trough will bring some showers toward
KCLL after 09z. A mix of MVFR/VFR ceilings are expected this
afternoon transitioning to a mix of IFR/MVFR overnight with the
best potential for IFR ceilings over northern TAF sites. Models
are trending drier for Tuesday and not much confidence in how
meso-scale features will play out, so will continue advertising
VCSH/VCTS. 43
&&
.PREV DISCUSSION... /ISSUED 427 AM CDT Mon May 17 2021/
DISCUSSION...
We are now firmly into what will be a week-long pattern of
considerably more disturbed weather, complete with multiple rounds
of showers and thunderstorms, some of them with heavy rain
involved, and only brief respites between aforementioned rounds of
rain.
There are a lot of words below that really dig into specifics of
what we're expecting, why we expect them, and beyond that, what we
can and cannot confidently predict on this early Monday morning.
Please enjoy them for the technical breakdown they are. If you're
in a hurry, the TL;DR is this: We find ourselves in a very
conducive environment for showers and thunderstorms each day
across Southeast Texas. The Tuesday night through Thursday morning
stretch likely carries the highest threat for flooding rains, but
that threat is not entirely absent any day this week. Please make
it a point to be aware of the weather situation this week and keep
up with the latest forecast information.
SHORT TERM [Through Tuesday]...
Today will be the second day of the multi-day wet weather pattern
across SE Texas. Another upper level shortwave will round the base
of an upper low located over the Four Corners today and better upper
level diffluence sets up over Southeast TX. Though low level
moisture content will be somewhat less today (roughly around 0.20-
0.30 inches less), the air mass in place continues to be quite
unstable, in particular, during the afternoon to early evening
hours. The 06Z NAM forecast sounding, for example, show MUCAPE
values between the 3000-4000 J/kg around 21-00Z with 0 CIN. It also
contains 700-500MB lapse rates in the 7 C/km range. A pocket of much
drier air lies between the 800-600MB levels with a moisture increase
just above it. It seems that the areas north of I-10 will be the
most vulnerable for todays' weather. Strong gusty winds and hail may
accompany the stronger storms. The potential for minor flooding due
to slow moving storms producing heavy to torrential rainfall is also
possible, though knowing an exact location for it is still hard to
tell. A Flash Flood Watch may be needed, however, models continue to
have difficulty with initiation, timing, and intensity and have thus
decided to wait and see how the weather develops today before
pulling the trigger on the Flash Flood Watch. The potential is
definitely there however, so it is best to stay watchful and ready.
Tuesday will be the third consecutive stormy day given that
Southeast TX will still have the unstable airmass in place while
having a stronger influence with the trough deepening southward as
the upper closed low finally begins to shift and a more favorable
wind pattern for storms develops aloft. There is also a bigger
consensus on strong storm development along a dry line situated
along the TX panhandle and Western TX. Storms amplifying over
Central TX look to propagate into our northern counties sometime in
the afternoon/evening where locally the environment could very well
support their livelihood. Thus, Southeast TX may end up having a
combination of both locally developed storms and storms rolling in
from the NW. Again, the higher PoPs lie along areas north of I-10.
Therefore, if we are able to obtain enough rainfall today to issue a
Flash Flood Watch for our northern counties, then it will be likely
that the Watch will be continued well into Tuesday or Wednesday due
to this second wave of activity across these sectors. WPC has a
Slight Risk for Excessive Rainfall for northern and western portions
of the CWA for Tuesday with a Marginal Risk extending elsewhere. SPC
also has a Slight Risk for Severe Thunderstorms for the northern
portions of the CWA. It will definitely be an interesting couple of
days for us here in SE Texas.
LONG TERM [Tuesday Night Through Monday]...
From a deterministic standpoint, I'm not sure there's much that
can be said about this midweek period that I haven't already
written about in the past few nights. There remains strong model
consensus for an environment conducive to heavy rains across
Southeast Texas deep into this week. Weather will still be driven
by a closed upper low that will definitely overstay its welcome,
if it hasn't already. Per NAEFS, precipitable water still looks
to rise to around or above the 90th percentile, while an inflow
jet from the Gulf will also start to be nudging up towards the
90th percentile as well. The Euro ensemble is even more
aggressive, with precipitable water exceeding the 99th percentile
and the inflow jet easily exceeding the 90th percentile; perhaps
even beginning the push the 98th percentile.
It seems pretty safe to say that somebody, somewhere in the
eastern half of Texas is going to get slammed with a lot of rain.
The deterministics have actually been trending downward in their
QPF, though trending down from a cumulative 20 inches closer to
"just" a foot doesn't seem terribly helpful. Location also varies
significantly among the models. The GFS, Canadian, and possibly
the NAM, now that it's coming into range, tend to favor the
heaviest axis of rain well inland, perhaps even northwest of our
area entirely. The Euro, on the other hand, swings a lobe of
midlevel vorticity further south, and really tries to focus the
action on a coastal trough.
I'm not even sure, given all the mesoscale factors that will
influence rainfall placement and amounts, that these trends are
even real or particularly helpful to the forecast. When it comes
to the big picture, best to focus on the environment and a broad
sketch of the potential than the specifics right now. Yesterday,
even short range CAM guidance struggled mightily with exactly
where and how much rain would fall. What they did show? Potential
for heavy rain somewhere, and where we got heavy rain was around
Matagorda Bay.
There are probably some things we can see as relatively mutually
exclusive. Typically in these setups, convection offshore or near
the coast can rob moisture from areas further inland, cutting off
areas further north from the rich moisture inflow jet. So if
guidance tends to start favoring a coastal trough more, we may
focus our strongest wording there. On the flip side, if
significant coastal convection doesn't materialize, that would
increase the danger for heavy rains further inland as that rich
Gulf moisture surges north.
We'll be searching for signs for a specific scenario such as the
couple I've laid out here to try to give as much lead time as
possible on where the highest risk is. It is the primary reason
why a flash flood watch is not being issued on this shift, in
hopes that the highest threat area will become apparent to the day
shift (regardless, expect a watch fairly soon - we are running out
of time). But sometimes, mesoscale features are just so
important, and so difficult to forecast at range, that we'll be
refining the forecast right into an event. In other words, to
quote the s c i e n t i s t who must predict the future,
"Sometimes science is so difficult it makes me sad".
Beyond the midweek, there are also not much large-scale change in
the forecast into the upcoming weekend. Even though the main
upper low gets drawn up towards the Great Lakes, remnant vorticity
continues to linger over the area. This should allow the broad
environment to back down from the amped up levels leading to the
heavy midweek rain, but should still support more rounds of
showers and thunderstorms late this week and into the weekend.
Eventually - I promise! - the strong eastern US ridge will build
far enough west to return us to a drier, more typical late spring
setup. This is still not entirely dry...but at least should be
more in the vein of a handful of showers and storms through the
course of a day while most stay dry, rather than widespread
wettings for large swaths of the area.
MARINE...
Cautions will remain across the Gulf waters today along with a High
Risk of Rip Currents for the Gulf facing beaches. Exercise caution
if heading to the coast this week and remember to only enter the
water near a trained lifeguard.
With surface pressures deepening to our west, the resultant
tightening of the gradient over SE TX will continue to result in
elevated winds and seas today. Stronger winds Tuesday afternoon into
Wednesday will build seas to around 6 to 8 ft and will require
Advisories for the Gulf waters. Stormy weather will continue through
the rest of the work week as several disturbances move through TX.
Stronger storms will be capable of producing locally higher winds
and seas, frequent lightning and waterspouts.
HYDROLOGY...
With yesterday's rainfall, several rivers running into Matagorda
Bay went into flood and had flood warnings issued. As of early
this morning, the following locations still have warnings in
effect: Tres Palacios at Midfield (In moderate flood, with an
expected crest this evening near major flood), the Lavaca River at
Edna (cresting now in minor flood), and East Mustang Creek at
Louise (in minor flood and falling, expected to come out of flood
stage later this morning). In the east, the Trinity at Moss Bluff
is still in minor flood, and is likely to remain there for several
days.
Additionally, the Trinity at Liberty is a point to watch closely
for flooding impacts this week, but the timing of when the river
may reach flood stage and how high the level is expected to reach
is extremely dependent on how much rainfall occurs in the next
couple of days. A flood warning may be needed when these impacts
can be anticipated with greater confidence.
&&
.PRELIMINARY POINT TEMPS/POPS...
College Station (CLL) 86 71 85 70 80 / 60 30 80 70 90
Houston (IAH) 84 73 85 73 83 / 70 30 70 70 80
Galveston (GLS) 82 75 84 75 83 / 60 20 40 50 70
&&
.HGX WATCHES/WARNINGS/ADVISORIES...
TX...High Rip Current Risk through Tuesday evening for the following
zones: Bolivar Peninsula...Brazoria Islands...Galveston
Island...Matagorda Islands.
GM...NONE.
&&
Discussion...99
Aviation/Marine...99The office that day
Everything else NWS Houston/Galveston, TX issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 16, 7:56 PM CDT | Special Marine Warning | HGX | 34 min | |
| May 16, 8:27 PM CDT | River Flood Warning | HGX | Jackson | 11 hr |
| May 16, 8:42 PM CDT | Special Marine Warning | HGX | 48 min | |
| May 16, 10:16 PM CDT | Special Marine Warning | HGX | 44 min | |
| May 16, 11:11 PM CDT | Special Marine Warning | HGX | 64 min | |
| May 17, 1:16 AM CDT | Special Marine Warning | HGX | 89 min | |
| May 17, 2:45 AM CDT | Special Marine Warning | HGX | 45 min | |
| May 17, 12:57 PM CDT | Areal Flood Advisory | HGX | Liberty | 2 hr |
| May 17, 2:06 PM CDT | Flash Flood Warning | HGX | Liberty | 3 hr |
| May 17, 2:08 PM CDT | Special Weather Statement | HGX | San Jacinto | 52 min |
| May 17, 2:09 PM CDT | Areal Flood Advisory | HGX | Grimes, Montgomery, San Jacinto, Walker, Waller, Washington | 3 hr |
| May 17, 2:44 PM CDT | Special Weather Statement | HGX | Liberty, Montgomery | 46 min |
| May 17, 2:59 PM CDT | Areal Flood Advisory | HGX | Austin, Colorado, Harris, Liberty, Montgomery, San Jacinto and 2 more | 3 hr |
| May 17, 3:13 PM CDT | Areal Flood Advisory | HGX | Chambers, Harris, Liberty, Montgomery | 2 hr |
| May 17, 3:19 PM CDT | Special Weather Statement | HGX | Austin, Colorado | 56 min |
| May 17, 3:21 PM CDT | Flash Flood Warning | HGX | Chambers, Harris, Liberty | 3 hr |
| May 17, 3:23 PM CDT | Special Weather Statement | HGX | Chambers, Harris | 67 min |
| May 17, 3:46 PM CDT | Special Marine Warning | HGX | 89 min | |
| May 17, 4:08 PM CDT | Areal Flood Advisory | HGX | Harris | 112 min |
| May 17, 4:25 PM CDT | Special Weather Statement | HGX | Austin, Brazoria, Colorado, Fort Bend, Galveston, Harris and 1 more | 65 min |
| May 17, 5:02 PM CDT | Areal Flood Advisory | HGX | Brazoria, Fort Bend, Galveston, Harris | 118 min |
| May 17, 5:07 PM CDT | River Flood Warning | HGX | Liberty | 36 days |
| May 17, 5:15 PM CDT | Special Marine Warning | HGX | 45 min | |
| May 17, 5:30 PM CDT | Special Marine Warning | HGX | 90 min | |
| May 17, 5:37 PM CDT | Areal Flood Advisory | HGX | Austin, Colorado, Fort Bend, Harris, Waller, Wharton | 113 min |
| May 17, 5:44 PM CDT | Special Weather Statement | HGX | Fort Bend | 61 min |
| May 17, 6:14 PM CDT | Areal Flood Advisory | HGX | Brazoria, Fort Bend, Galveston, Harris, Matagorda, Wharton | 2 hr |
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.