Alert archive / Texas / Severe Thunderstorm Watches in 2020

Severe Thunderstorm Watch 98

April 9, 20205 counties in Texas

The Storm Prediction Center issued this severe thunderstorm watch at Apr 9, 2020, 5:45 PM CDT for 5 counties in Texas. It was in force for 4 hr.

The area

The outline as issued.

The facts

Issued
Apr 9, 2020, 5:45 PM CDT (22:45 UTC)
Expired
Apr 9, 2020, 9:58 PM CDT
In force
4 hr
Issued by
the Storm Prediction Center
Largest hail expected
2.5 in
Strongest gust expected
60 kt

Counties Brooks County, TX, Hidalgo County, TX, Jim Hogg County, TX, Starr County, TX, Zapata County, TX

The radar

The Corpus Christi radar (KCRP), 147 km from the middle of the area, began a volume at 22:46 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
10%
One or more EF2 to EF5 tornadoes
2%
Ten or more severe wind reports
60%
One or more gusts of 65 knots or more
20%
Ten or more severe hail reports
60%
One or more hailstones of 2 inches or more
60%
Six or more combined severe hail and wind reports
95%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Apr 9, 6:59 PM CDTSevere Thunderstorm WarningBROStarr, Zapata55 min

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 12:00Z, 10.8 hours before the alert went out and 155 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 12:00Z on 2020-04-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1938 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 12:00Z on 2020-04-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -26 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
1938 J/kg
Mixed-layer CIN
-226 J/kg
Mixed-layer LCL
1008 m above ground
0-6 km bulk shear
39 kt
0-1 km storm-relative helicity
-26 m²/s²
0-3 km storm-relative helicity
-17 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.6

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 9, 12:13 PM CDTMesoscale DiscussionSPCBandera, Bastrop, Bell, Blanco, Burnet, Caldwell and 19 more2 hr
Apr 9, 2:47 PM CDTSevere Thunderstorm WatchSPCAnderson, Angelina, Atascosa, Austin, Bandera, Bastrop and 69 more7 hr
Apr 9, 5:20 PM CDTMesoscale DiscussionSPCAngelina, Austin, Brazoria, Chambers, Colorado, Fort Bend and 19 more115 min
Apr 9, 5:40 PM CDTMesoscale DiscussionSPCBrooks, Cameron, Duval, Hidalgo, Jim Hogg, Jim Wells and 7 more2 hr

Nearby

Severe Thunderstorm Watches in Texas, 2020Every severe thunderstorm 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.