Alert archive / Texas / Flash Flood Warnings in 2018

Flash Flood Warning 2, NWS Austin/San Antonio, TX

March 28, 20184 counties in Texas

NWS Austin/San Antonio, TX issued this flash flood warning at Mar 28, 2018, 3:56 AM CDT for 4 counties in Texas. It was in force for 6 hr. 8 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Mar 28, 2018, 3:56 AM CDT (08:56 UTC)
Expired: Mar 28, 2018, 9:30 AM CDT
In force: 6 hr
Issued by: NWS Austin/San Antonio, TX
Area: Storm-based polygon
Flood severity: None

Counties Comal County, TX, Hays County, TX, Travis County, TX, Williamson County, TX

The radar

The Austin/San Antonio radar (KEWX), 32 km from the middle of the area, began a volume at 08:58 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.

What was reported inside it

Time	Report	Where	Remark
Mar 28, 5:03 AM CDT	FLASH FLOOD	2 Nne Austin, TX	STREET FLOODING REPORTED IN THE HYDE PARK NEIGHBORHOOD OF AUSTIN.
Mar 28, 5:25 AM CDT	FLASH FLOOD	2 Nnw Anderson Mill, TX	LAKELINE BLVD IN CEDAR PARK CLOSED BETWEEN LITTLE ELM AND OLD MILL DUE TO FLOODING.
Mar 28, 5:28 AM CDT	FLASH FLOOD	3 Wsw Hutto, TX	NUMEROUS LOW WATER CROSSINGS CLOSED ACROSS WILLIAMSON COUNTY.
Mar 28, 5:33 AM CDT	FLASH FLOOD	1 Nne Kyle, TX	ROAD CLOSURES DUE TO FLOODING ACROSS THE CITY OF KYLE.
Mar 28, 5:46 AM CDT	FLASH FLOOD	Lost Creek, TX	NUMEROUS LOW WATER CROSSINGS CLOSED ACROSS TRAVIS COUNTY AND THE CITY OF AUSTIN.
Mar 28, 6:15 AM CDT	HEAVY RAIN 4.66	3 W Kyle, TX	USGS RAIN GAUGE AT BLANCO RIVER NEAR KYLE REPORTS 4.66 INCHES OF RAIN SINCE MIDNIGHT.
Mar 28, 7:19 AM CDT	HEAVY RAIN 4.35	2 Sw Bergstrom Internat, TX	LCRA HYDROMET SITE AT ONION CREEK AND US 183 REPORTS 4.35 INCHES OF RAIN SINCE MIDNIGHT.
Mar 28, 7:33 AM CDT	FLASH FLOOD	5 Wnw Coupland, TX	WILLIAMSON COUNTY EM REPORTS ADDITIONAL ROAD CLOSURES DUE TO HIGH WATER ACROSS THE COUNTY.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Corpus Christi, TX (KCRP), launched 00:00Z, 8.9 hours before the alert went out and 261 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 2154 J/kg
Mixed-layer CIN: -37 J/kg
Mixed-layer LCL: 579 m above ground
0-6 km bulk shear: 37 kt
0-1 km storm-relative helicity: 114 m²/s²
0-3 km storm-relative helicity: 62 m²/s²
Significant tornado parameter: 1.1
Supercell composite: 6.4

Open this sounding in Storm Lab

The text

As transmitted.

934 
WGUS54 KEWX 280856
FFWEWX
TXC091-209-453-491-281145-
/O.NEW.KEWX.FF.W.0002.180328T0856Z-180328T1145Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Austin/San Antonio TX
356 AM CDT WED MAR 28 2018

The National Weather Service in Austin San Antonio has issued a

* Flash Flood Warning for...
  Southwestern Williamson County in south central Texas...
  Hays County in south central Texas...
  Travis County in south central Texas...
  Comal County in south central Texas...

* Until 645 AM CDT

* At 351 AM CDT, Doppler radar indicated thunderstorms producing 
  heavy rain repeating across the I-35 corridor and adjacent 
  Escapement areas. Up to three inches of rain have already fallen. 
  Flash flooding is expected to begin shortly.

* Some locations that will experience flooding include...
  Austin, Round Rock, New Braunfels, Cedar Park, Georgetown, San
  Marcos, Pflugerville, Schertz, Kyle, Buda, Selma, Dripping Springs,
  Wimberley, Tanglewood Forest, Anderson Mill, Austin Bergstrom Int
  Airport, Windemere, Canyon Lake Dam, Leander and Hutto.

Additional rainfall amounts of 1 to 3 inches are possible in the 
warned area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Be especially cautious at night when it is harder to recognize the
dangers of flooding.

Excessive runoff from heavy rainfall will cause flooding of small
creeks and streams, urban areas, highways, streets, and underpasses
as well as other drainage areas and low lying spots.

In hilly terrain there are hundreds of low water crossings which are
potentially dangerous in heavy rain. Do not attempt to cross flooded
roads. Find an alternate route.

&&

LAT...LON 3068 9763 3044 9737 2993 9782 2988 9789
      2986 9790 2986 9788 2983 9791 2970 9806
      2959 9831 2970 9835 2972 9834 2974 9837
      2978 9858 2982 9856 3005 9828 3058 9804

$$

CP

2 follow-up statements

976 
WGUS74 KEWX 281008
FFSEWX

Flash Flood Statement
National Weather Service Austin/San Antonio TX
508 AM CDT WED MAR 28 2018

TXC091-209-453-491-281145-
/O.CON.KEWX.FF.W.0002.000000T0000Z-180328T1145Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Williamson TX-Hays TX-Travis TX-Comal TX-
508 AM CDT WED MAR 28 2018

...THE FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 645 AM CDT FOR
SOUTHWESTERN WILLIAMSON...HAYS...TRAVIS AND COMAL COUNTIES...

At 507 AM CDT, Doppler radar indicated thunderstorms producing light 
to moderate rain across Comal, Hays, Travis, and southwestern 
Williamson counties. Up to three inches of rain have already fallen. 
Flash flooding will continue.

Some locations that will experience flooding include...
Austin, Round Rock, New Braunfels, Cedar Park, Georgetown, San
Marcos, Pflugerville, Schertz, Kyle, Buda, Selma, Dripping Springs,
Wimberley, Tanglewood Forest, Anderson Mill, Austin Bergstrom Int
Airport, Windemere, Canyon Lake Dam, Leander and Hutto.

Additional rainfall amounts of up to 1 inch are possible in the 
warned area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Be especially cautious at night when it is harder to recognize the
dangers of flooding.

In hilly terrain there are hundreds of low water crossings which are
potentially dangerous in heavy rain. Do not attempt to cross flooded
roads. Find an alternate route.

&&

LAT...LON 3068 9763 3044 9737 2993 9782 2988 9789
      2986 9790 2986 9788 2983 9791 2970 9806
      2959 9831 2970 9835 2972 9834 2974 9837
      2978 9858 2982 9856 3005 9828 3058 9804

$$

CP

768 
WGUS54 KEWX 281137
FFWEWX
TXC091-209-453-491-281430-
/O.EXT.KEWX.FF.W.0002.000000T0000Z-180328T1430Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Austin/San Antonio TX
637 AM CDT WED MAR 28 2018

The National Weather Service in Austin San Antonio has extended the

* Flash Flood Warning for...
  Southwestern Williamson County in south central Texas...
  Hays County in south central Texas...
  Travis County in south central Texas...
  Comal County in south central Texas...

* Until 930 AM CDT

* At 635 AM CDT, Doppler radar indicated isolated thunderstorms 
  producing moderate rain across the warned area. Up to four inches 
  of rain have already fallen. Flash flooding is occurring on some 
  rivers and creeks. This flooding will continue for the next couple 
  of hours. 

* Some locations that will experience flooding include...
  Austin, Round Rock, New Braunfels, Cedar Park, Georgetown, San
  Marcos, Pflugerville, Schertz, Kyle, Buda, Selma, Dripping Springs,
  Wimberley, Tanglewood Forest, Anderson Mill, Austin Bergstrom Int
  Airport, Windemere, Canyon Lake Dam, Leander and Hutto.

Additional rainfall amounts of up to 1/2 inch are possible in the 
warned area.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Be especially cautious at night when it is harder to recognize the
dangers of flooding.

In hilly terrain there are hundreds of low water crossings which are
potentially dangerous in heavy rain. Do not attempt to cross flooded
roads. Find an alternate route.

&&

LAT...LON 3068 9763 3044 9737 2993 9782 2988 9789
      2986 9790 2986 9788 2983 9791 2970 9806
      2959 9831 2970 9835 2972 9834 2974 9837
      2978 9858 2982 9856 3005 9828 3058 9804

$$

CP

The office that day

Everything else NWS Austin/San Antonio, TX issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Mar 27, 7:56 PM CDT	Flash Flood Watch	EWX	Bastrop, Bexar, Blanco, Burnet, Caldwell, Comal and 10 more	23 hr
Mar 27, 10:13 PM CDT	Special Weather Statement	EWX	Dimmit	47 min
Mar 27, 10:30 PM CDT	Special Weather Statement	EWX	Medina	45 min
Mar 27, 11:15 PM CDT	Special Weather Statement	EWX	Medina	30 min
Mar 27, 11:17 PM CDT	Special Weather Statement	EWX	Medina	43 min
Mar 27, 11:46 PM CDT	Severe Thunderstorm Warning	EWX	Dimmit, Maverick	59 min
Mar 27, 11:52 PM CDT	Severe Thunderstorm Warning	EWX	Frio	53 min
Mar 27, 11:55 PM CDT	Areal Flood Advisory	EWX	Medina, Uvalde	3 hr
Mar 27, 11:56 PM CDT	Special Weather Statement	EWX	Bandera	64 min
Mar 28, 12:08 AM CDT	Special Weather Statement	EWX	Val Verde	52 min
Mar 28, 12:21 AM CDT	Severe Thunderstorm Warning	EWX	Atascosa, Bexar, Medina	39 min
Mar 28, 12:34 AM CDT	Severe Thunderstorm Warning	EWX	Dimmit	41 min
Mar 28, 12:44 AM CDT	Special Weather Statement	EWX	Gillespie	46 min
Mar 28, 1:05 AM CDT	Special Weather Statement	EWX	Llano	40 min
Mar 28, 1:26 AM CDT	Special Weather Statement	EWX	Maverick	49 min
Mar 28, 1:36 AM CDT	Areal Flood Advisory	EWX	Bexar, Medina	3 hr
Mar 28, 2:02 AM CDT	Special Weather Statement	EWX	Comal	28 min
Mar 28, 2:25 AM CDT	Areal Flood Advisory	EWX	Blanco, Comal, Hays, Kendall	3 hr
Mar 28, 2:38 AM CDT	Special Weather Statement	EWX	Dimmit	37 min
Mar 28, 2:40 AM CDT	Flash Flood Warning	EWX	Bexar, Medina	6 hr
Mar 28, 3:12 AM CDT	Areal Flood Advisory	EWX	Comal, Hays, Travis	3 hr
Mar 28, 4:12 AM CDT	Areal Flood Advisory	EWX	Bexar, Guadalupe, Wilson	3 hr
Mar 28, 4:51 AM CDT	Tornado Warning	EWX	Caldwell	24 min
Mar 28, 7:34 AM CDT	River Flood Warning	EWX	Travis	15 hr
Mar 28, 7:57 AM CDT	Special Weather Statement	EWX	Uvalde	48 min
Mar 28, 8:09 AM CDT	Severe Thunderstorm Warning	EWX	Medina, Uvalde, Zavala	51 min
Mar 28, 8:33 AM CDT	Severe Thunderstorm Warning	EWX	Medina	42 min
Mar 28, 8:48 AM CDT	Flash Flood Warning	EWX	Medina	3 hr
Mar 28, 9:16 AM CDT	Severe Thunderstorm Warning	EWX	Atascosa, Bexar, Medina	59 min
Mar 28, 9:55 AM CDT	Flash Flood Warning	EWX	Bexar, Comal, Guadalupe	5 hr
Mar 28, 10:16 AM CDT	Special Weather Statement	EWX	Bexar	44 min
Mar 28, 10:39 AM CDT	Flash Flood Warning	EWX	Bastrop, Caldwell, Comal, Guadalupe, Hays, Travis and 1 more	3 hr
Mar 28, 10:57 AM CDT	Special Weather Statement	EWX	Guadalupe	48 min
Mar 28, 10:59 AM CDT	River Flood Warning	EWX	Bexar	7 hr
Mar 28, 11:40 AM CDT	Special Weather Statement	EWX	Caldwell	50 min
Mar 28, 2:17 PM CDT	River Flood Warning	EWX	Bexar, Wilson	34 hr
Mar 28, 2:42 PM CDT	River Flood Warning	EWX	Bexar	18 hr

Nearby

Flash Flood Warnings in Texas, 2018 Every flash flood warning in 2018

Sources

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