Alert archive / Texas / Flash Flood Watches in 2017

Flash Flood Watch 5, NWS Houston/Galveston, TX

May 22, 20179 counties in Texas

NWS Houston/Galveston, TX issued this flash flood watch at May 22, 2017, 4:32 AM CDT for 9 counties in Texas. It was in force for 8 hr.

The area

The counties it named.

The facts

Issued
May 22, 2017, 4:32 AM CDT (09:32 UTC)
Expired
May 22, 2017, 1:00 PM CDT
In force
8 hr
Issued by
NWS Houston/Galveston, TX
Flood severity
None

Counties Brazoria County, TX, Chambers County, TX, Fort Bend County, TX, Galveston County, TX, Harris County, TX, Jackson County, TX, Liberty County, TX, Matagorda County, TX, Wharton County, TX

The radar

The Houston radar (KHGX), 43 km from the middle of the area, began a volume at 09:33 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

Corpus Christi, TX (KCRP), launched 00:00Z, 9.5 hours before the alert went out and 258 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, Corpus Christi, TX at 00:00Z on 2017-05-22Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2241 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, Corpus Christi, TX at 00:00Z on 2017-05-22The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 24 square meters per square second.193958Sfc1 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
2241 J/kg
Mixed-layer CIN
-43 J/kg
Mixed-layer LCL
836 m above ground
0-6 km bulk shear
46 kt
0-1 km storm-relative helicity
24 m²/s²
0-3 km storm-relative helicity
76 m²/s²
Significant tornado parameter
0.5
Supercell composite
3.2

Open this sounding in Storm Lab

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 21, 11:55 PM CDT, 4 hours 37 minutes earlier.

Area forecast discussion, May 21, 11:55 PM CDT, 4 hours 37 minutes before
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Hazardous weather outlook, May 21, 4:19 PM CDT, 12 hours 13 minutes before
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In the hours before

Special weather statement, May 22, 2:36 AM CDT, 1 hour 56 minutes before
Special Weather Statement
National Weather Service Houston/Galveston TX
236 AM CDT MON MAY 22 2017

TXZ236-220815-
Matagorda TX-
236 AM CDT MON MAY 22 2017

...SIGNIFICANT WEATHER ADVISORY FOR SOUTHWESTERN MATAGORDA COUNTY
UNTIL 315 AM CDT...

At 235 AM CDT, Doppler radar was tracking a strong thunderstorm near
Port Oconnor, moving northeast at 15 mph.

Dime size hail and winds in excess of 40 mph will be possible with
this storm.

This storm will remain over mainly rural areas of southwestern
Matagorda County.

LAT...LON 2838 9638 2840 9639 2840 9637 2846 9641
      2846 9642 2848 9644 2852 9641 2855 9633
      2857 9637 2862 9633 2847 9609 2841 9616
      2838 9623
TIME...MOT...LOC 0735Z 222DEG 11KT 2839 9639

The office that day

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

IssuedProductOfficeCountiesLasted
May 21, 9:18 PM CDTSpecial Marine WarningHGX27 min
May 21, 11:45 PM CDTSpecial Marine WarningHGX30 min
May 22, 12:13 AM CDTSpecial Marine WarningHGX62 min
May 22, 12:29 AM CDTSpecial Marine WarningHGX31 min
May 22, 12:53 AM CDTSpecial Marine WarningHGX67 min
May 22, 2:36 AM CDTSpecial Weather StatementHGXCalhoun39 min
May 22, 2:37 AM CDTSpecial Marine WarningHGX53 min
May 22, 3:35 AM CDTSpecial Marine WarningHGX55 min
May 22, 3:42 AM CDTSpecial Marine WarningHGX63 min
May 22, 3:46 AM CDTSmall Craft AdvisoryHGX13 hr
May 22, 4:27 AM CDTSpecial Marine WarningHGX33 min
May 22, 4:32 AM CDTSpecial Marine WarningHGX58 min
May 22, 4:59 AM CDTSpecial Marine WarningHGX46 min
May 22, 5:00 AM CDTSpecial Marine WarningHGX45 min
May 22, 5:33 AM CDTSpecial Marine WarningHGX57 min
May 22, 5:33 AM CDTSpecial Marine WarningHGX57 min
May 22, 5:38 AM CDTSpecial Weather StatementHGXMatagorda37 min
May 22, 5:54 AM CDTSpecial Marine WarningHGX66 min
May 22, 6:01 AM CDTSpecial Weather StatementHGXHarris44 min
May 22, 6:07 AM CDTSpecial Weather StatementHGXChambers38 min
May 22, 6:23 AM CDTAreal Flood AdvisoryHGXFort Bend, Harris52 min
May 22, 6:47 AM CDTAreal Flood AdvisoryHGXBrazoria, Matagorda118 min
May 22, 6:52 AM CDTAreal Flood AdvisoryHGXHarris53 min
May 22, 7:01 AM CDTSpecial Weather StatementHGXLiberty59 min
May 22, 7:47 AM CDTFlash Flood WarningHGXBrazoria, Matagorda3 hr
May 22, 8:02 AM CDTSpecial Marine WarningHGX58 min
May 22, 8:05 AM CDTSpecial Weather StatementHGXLiberty25 min
May 22, 8:15 AM CDTAreal Flood AdvisoryHGXFort Bend60 min
May 22, 8:17 AM CDTAreal Flood AdvisoryHGXBrazos, Grimes, Madison, Walker58 min
May 22, 8:42 AM CDTAreal Flood AdvisoryHGXBrazoria, Fort Bend, Galveston, Matagorda, Wharton2 hr
May 22, 8:45 AM CDTSpecial Marine WarningHGX60 min
May 22, 8:56 AM CDTSpecial Marine WarningHGX64 min
May 22, 9:31 AM CDTAreal Flood AdvisoryHGXGrimes, Montgomery, Polk, San Jacinto, Walker59 min
May 22, 9:33 AM CDTAreal Flood AdvisoryHGXBrazoria, Galveston, Matagorda57 min
May 22, 9:41 AM CDTSpecial Marine WarningHGX64 min
May 22, 9:43 AM CDTSpecial Marine WarningHGX32 min
May 22, 10:05 AM CDTTornado WarningHGXBrazoria, Galveston25 min
May 22, 10:28 AM CDTSevere Thunderstorm WarningHGXBrazoria, Galveston47 min
May 22, 10:34 AM CDTAreal Flood AdvisoryHGXGrimes, Montgomery, Polk, San Jacinto, Trinity, Walker56 min
May 22, 10:38 AM CDTSpecial Marine WarningHGX67 min
May 22, 10:41 AM CDTSpecial Marine WarningHGX94 min
May 22, 10:46 AM CDTAreal Flood AdvisoryHGXBrazoria, Galveston, Harris119 min
May 22, 10:58 AM CDTSevere Thunderstorm WarningHGXGalveston47 min
May 22, 11:01 AM CDTSpecial Weather StatementHGXGalveston44 min
May 22, 11:18 AM CDTSpecial Marine WarningHGX57 min
May 22, 11:20 AM CDTTornado WarningHGXGalveston25 min
May 22, 11:31 AM CDTAreal Flood AdvisoryHGXMontgomery, Polk, San Jacinto, Trinity, Walker59 min
May 22, 11:41 AM CDTTornado WarningHGXGalveston49 min
May 22, 11:51 AM CDTSpecial Marine WarningHGX54 min
May 22, 12:26 PM CDTSpecial Marine WarningHGX64 min
May 22, 12:31 PM CDTAreal Flood AdvisoryHGXLiberty, Montgomery, Polk, San Jacinto59 min
May 22, 12:47 PM CDTAreal Flood AdvisoryHGXChambers, Galveston58 min
May 22, 12:57 PM CDTSpecial Marine WarningHGX48 min
May 22, 1:43 PM CDTSpecial Marine WarningHGX32 min
May 22, 1:52 PM CDTSpecial Marine WarningHGX38 min
May 22, 1:58 PM CDTAreal Flood AdvisoryHGXJackson, Matagorda, Wharton62 min
May 22, 2:06 PM CDTAreal Flood AdvisoryHGXHarris54 min
May 22, 2:17 PM CDTSpecial Marine WarningHGX58 min
May 22, 2:51 PM CDTSpecial Marine WarningHGX39 min
May 22, 2:59 PM CDTSpecial Weather StatementHGXMatagorda46 min
May 22, 4:14 PM CDTAreal Flood AdvisoryHGXMatagorda2 hr
May 22, 4:53 PM CDTSpecial Weather StatementHGXMatagorda67 min
May 22, 5:23 PM CDTSpecial Weather StatementHGXBrazoria37 min
May 22, 5:51 PM CDTAreal Flood AdvisoryHGXBrazoria54 min

Nearby

Flash Flood Watches in Texas, 2017Every flash flood watch in 2017

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.