Alert archive / Texas / Flash Flood Warnings in 2023

Flash Flood Warning 6, NWS Houston/Galveston, TX

May 8, 2023Harris County, Montgomery County, Texas

NWS Houston/Galveston, TX issued this flash flood warning at May 8, 2023, 6:37 PM CDT for Harris County, Montgomery County, Texas. It was in force for 23 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: May 8, 2023, 6:37 PM CDT (23:37 UTC)
Expired: May 8, 2023, 7:00 PM CDT
In force: 23 min
Issued by: NWS Houston/Galveston, TX
Area: Storm-based polygon
Flood severity: None

Counties Harris County, TX, Montgomery County, TX

The radar

The Houston radar (KHGX), 76 km from the middle of the area, began a volume at 23:37 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, 11.6 hours before the alert went out and 216 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: 789 J/kg
Mixed-layer CIN: -131 J/kg
Mixed-layer LCL: 823 m above ground
0-6 km bulk shear: 32 kt
0-1 km storm-relative helicity: 81 m²/s²
0-3 km storm-relative helicity: 129 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.9

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this flash flood warning 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 warning went out at May 8, 3:57 PM CDT, 2 hours 40 minutes earlier.

Area forecast discussion, May 8, 3:57 PM CDT, 2 hours 40 minutes before

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In the hours before

Special weather statement, May 8, 3:16 PM CDT, 3 hours 21 minutes before

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Special weather statement, May 8, 3:23 PM CDT, 3 hours 14 minutes before

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Special weather statement, May 8, 3:59 PM CDT, 2 hours 38 minutes before

Special Weather Statement
National Weather Service Houston/Galveston TX
359 PM CDT Mon May 8 2023

TXZ163-176>179-195>199-212-213-082200-
San Jacinto TX-Madison TX-Walker TX-Brazos TX-Washington TX-
Grimes TX-Waller TX-Burleson TX-Polk TX-Inland Harris TX-
Montgomery TX-Houston TX-
359 PM CDT Mon May 8 2023

...Strong thunderstorms will impact portions of southeastern
Burleson, Grimes, Brazos, eastern Washington, western Montgomery,
northwestern San Jacinto, southwestern Houston, southern Madison,
northern Waller, western Polk, Walker and northwestern Harris
Counties through 500 PM CDT...

At 359 PM CDT, Doppler radar was tracking strong thunderstorms along
a line extending from near Snook to near Anderson to near Willis.
Movement was northeast at 20 mph.

HAZARD...Winds in excess of 40 mph and half inch hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
College Station, Bryan, northwestern Conroe, Huntsville, Navasota,
Hempstead, Willis, Prairie View, Madisonville, Pinehurst, Washington,
Hockley, Waller, Panorama Village, Magnolia, Somerville, New Waverly,
Pine Island, Point Blank and Montgomery.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Torrential rainfall is also occurring with these storms and may lead
to localized flooding. Do not drive your vehicle through flooded
roadways.

These storms may intensify, so be certain to monitor local radio
stations and available television stations for additional information
and possible warnings from the National Weather Service.

&&

LAT...LON 3097 9619 3093 9564 3076 9509 2996 9584
      3010 9621 3036 9667
TIME...MOT...LOC 2059Z 215DEG 18KT 3052 9644 3054 9592 3044 9556

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...40 MPH

Special weather statement, May 8, 5:25 PM CDT, 1 hour 12 minutes before

Special Weather Statement
National Weather Service Houston/Galveston TX
525 PM CDT Mon May 8 2023

TXZ199-213-082315-
Inland Harris TX-Montgomery TX-
525 PM CDT Mon May 8 2023

...A strong thunderstorm will impact portions of southwestern
Montgomery and north central Harris Counties through 615 PM CDT...

At 524 PM CDT, Doppler radar was tracking a strong thunderstorm
between The Woodlands and Tomball. Individual cells are moving
northeast at 5 mph, although it is expanding to the south and west.

HAZARD...Winds in excess of 40 mph and penny size hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around
         unsecured objects. Minor damage to outdoor objects is
         possible.

Locations impacted include...
Southeastern Conroe, Tomball, Pinehurst, The Woodlands, Spring, Oak
Ridge North, Shenandoah, Cut And Shoot, Stagecoach, Woodloch, The
Woodlands Pavillion, Hooks Airport, Chateau Woods, Splashtown and
Porter Heights.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building.

Torrential rainfall is also occurring with this storm and may lead to
localized flooding. Do not drive your vehicle through flooded
roadways.

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

&&

LAT...LON 2996 9561 3016 9572 3035 9540 3013 9524
TIME...MOT...LOC 2224Z 246DEG 5KT 3016 9555

MAX HAIL SIZE...0.75 IN
MAX WIND GUST...40 MPH

Local storm report, May 8, 5:59 PM CDT, 38 minutes before

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Special weather statement, May 8, 6:37 PM CDT, 0 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
May 7, 10:33 PM CDT	Small Craft Advisory	HGX		5 hr
May 8, 3:20 AM CDT	Rip Current Statement	HGX	Brazoria, Galveston, Matagorda	16 hr
May 8, 1:12 PM CDT	Special Weather Statement	HGX	Polk	33 min
May 8, 1:31 PM CDT	Special Weather Statement	HGX	Polk	29 min
May 8, 1:47 PM CDT	Special Weather Statement	HGX	Polk	28 min
May 8, 1:59 PM CDT	Special Weather Statement	HGX	Colorado	31 min
May 8, 2:17 PM CDT	Special Weather Statement	HGX	Polk	28 min
May 8, 2:27 PM CDT	Special Weather Statement	HGX	Washington	33 min
May 8, 2:30 PM CDT	Special Weather Statement	HGX	Colorado	30 min
May 8, 2:34 PM CDT	Severe Thunderstorm Warning	HGX	Brazos, Grimes, Waller, Washington	26 min
May 8, 3:00 PM CDT	Severe Thunderstorm Warning	HGX	Brazos, Grimes, Waller, Washington	16 min
May 8, 3:16 PM CDT	Special Weather Statement	HGX	Grimes	44 min
May 8, 3:23 PM CDT	Special Weather Statement	HGX	Waller	37 min
May 8, 3:30 PM CDT	Severe Thunderstorm Warning	HGX	Harris, Montgomery, Waller	30 min
May 8, 3:59 PM CDT	Special Weather Statement	HGX	Brazos, Grimes, Walker, Washington	61 min
May 8, 4:19 PM CDT	Areal Flood Advisory	HGX	Brazos, Grimes, Harris, Montgomery, Walker, Waller and 1 more	107 min
May 8, 5:25 PM CDT	Special Weather Statement	HGX	Montgomery	50 min
May 8, 5:30 PM CDT	Areal Flood Advisory	HGX	Harris, Montgomery	60 min
May 8, 5:52 PM CDT	Severe Thunderstorm Warning	HGX	Harris, Montgomery	38 min
May 8, 6:05 PM CDT	Areal Flood Advisory	HGX	Harris, Montgomery, Waller	55 min
May 8, 6:15 PM CDT	Severe Thunderstorm Warning	HGX	Colorado	27 min
May 8, 6:31 PM CDT	Areal Flood Advisory	HGX	Harris, Montgomery	63 min
May 8, 6:37 PM CDT	Special Weather Statement	HGX	Harris	23 min
May 8, 6:55 PM CDT	Severe Thunderstorm Warning	HGX	Harris	50 min

Nearby

Flash Flood Warnings in Texas, 2023 Every flash flood warning in 2023

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.