Alert archive / Texas / Tornado Watches in 2020

Tornado Watch 402

July 25, 202012 counties in Texas

The Storm Prediction Center issued this tornado watch at Jul 25, 2020, 11:05 PM CDT for 12 counties in Texas. It was in force for 9 hr.

The area

The outline as issued.

The facts

Issued
Jul 25, 2020, 11:05 PM CDT (04:05 UTC)
Expired
Jul 26, 2020, 7:55 AM CDT
In force
9 hr
Issued by
the Storm Prediction Center
Strongest gust expected
60 kt

Counties Brooks County, TX, Cameron County, TX, Duval County, TX, Hidalgo County, TX, Jim Wells County, TX, Kenedy County, TX, Kleberg County, TX, Live Oak County, TX, McMullen County, TX, Nueces County, TX, San Patricio County, TX, Willacy County, TX

The radar

The Corpus Christi radar (KCRP), 48 km from the middle of the area, began a volume at 04:08 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 SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes
30%
One or more EF2 to EF5 tornadoes
10%
Ten or more severe wind reports
5%
One or more gusts of 65 knots or more
5%
Ten or more severe hail reports
5%
One or more hailstones of 2 inches or more
5%
Six or more combined severe hail and wind reports
20%

Warnings issued inside it

13 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Jul 25, 11:55 PM CDTTornado WarningCRPDuval, Jim Wells, Live Oak, McMullen35 min
Jul 26, 12:30 AM CDTFlash Flood WarningBROHidalgo5 hr
Jul 26, 1:41 AM CDTFlash Flood WarningBROHidalgo2 hr
Jul 26, 2:14 AM CDTFlash Flood WarningBROCameron8 hr
Jul 26, 3:13 AM CDTFlash Flood WarningBROCameron, Hidalgo, Willacy7 hr
Jul 26, 3:24 AM CDTFlash Flood Warning Considerable damage threatBROCameron, Kenedy, Willacy7 hr
Jul 26, 3:27 AM CDTTornado WarningBROCameron33 min
Jul 26, 4:00 AM CDTTornado WarningBROCameron, Willacy30 min
Jul 26, 4:07 AM CDTTornado WarningBROCameron, Willacy23 min
Jul 26, 4:17 AM CDTFlash Flood WarningBROHidalgo, Starr6 hr
Jul 26, 5:48 AM CDTFlash Flood Warning EmergencyCatastrophic damage threatBROHidalgo13 hr
Jul 26, 6:00 AM CDTFlash Flood WarningBROCameron, Hidalgo, Willacy5 hr
Jul 26, 6:41 AM CDTFlash Flood WarningBROHidalgo4 hr

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Corpus Christi, TX (KCRP), launched 00:00Z, 4.1 hours before the alert went out and 45 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 2020-07-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 573 joules per kilogram.LCLEL10008507005003002001001 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 2020-07-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 98 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
573 J/kg
Mixed-layer CIN
-1 J/kg
Mixed-layer LCL
576 m above ground
0-6 km bulk shear
31 kt
0-1 km storm-relative helicity
98 m²/s²
0-3 km storm-relative helicity
94 m²/s²
Significant tornado parameter
0.2
Supercell composite
1.7

Open this sounding in Storm Lab

The text

As transmitted.

254 
WWUS20 KWNS 260403
SEL2  
SPC WW 260403
TXZ000-CWZ000-261400-

URGENT - IMMEDIATE BROADCAST REQUESTED
Tornado Watch Number 402
NWS Storm Prediction Center Norman OK
1105 PM CDT Sat Jul 25 2020

The NWS Storm Prediction Center has issued a

* Tornado Watch for portions of 
  South Texas
  Coastal Waters

* Effective this Saturday night and Sunday morning from 1105 PM
  until 900 AM CDT.

* Primary threats include...
  A couple tornadoes possible

SUMMARY...Hanna will continue to move west-southwestward across Deep
South Texas through the early morning hours of Sunday. Strong shear
on its northern and eastern periphery will account for some tornado
potential through the early morning hours of Sunday.

The tornado watch area is approximately along and 50 statute miles
east and west of a line from 40 miles north northwest of Corpus
Christi TX to 45 miles east southeast of Mcallen TX. For a complete
depiction of the watch see the associated watch outline update
(WOUS64 KWNS WOU2).

PRECAUTIONARY/PREPAREDNESS ACTIONS...

REMEMBER...A Tornado Watch means conditions are favorable for
tornadoes and severe thunderstorms in and close to the watch
area. Persons in these areas should be on the lookout for
threatening weather conditions and listen for later statements
and possible warnings.

&&

OTHER WATCH INFORMATION...CONTINUE...WW 401...

AVIATION...Tornadoes and a few severe thunderstorms with hail
surface and aloft to 0 inches. Extreme turbulence and surface wind
gusts to 60 knots. A few cumulonimbi with maximum tops to 500. Mean
storm motion vector 11040.

...Guyer

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 25, 7:23 PM CDTMesoscale DiscussionSPCCameron, Kenedy, Kleberg, Nueces, Willacy5 hr
Jul 26, 3:23 AM CDTMesoscale DiscussionSPCBrooks, Cameron, Duval, Hidalgo, Jim Wells, Kenedy and 6 more2 hr
Jul 26, 6:45 AM CDTMesoscale DiscussionSPCAransas, Brooks, Cameron, Duval, Hidalgo, Jim Wells and 5 more90 min
Jul 26, 7:51 AM CDTTornado WatchSPCBrooks, Cameron, Duval, Hidalgo, Jim Hogg, Jim Wells and 8 more14 hr
Jul 26, 12:13 PM CDTMesoscale DiscussionSPCBrooks, Cameron, Duval, Hidalgo, Jim Hogg, Jim Wells and 5 more2 hr

Nearby

Tornado Watches in Texas, 2020Every tornado watch in 2020

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.