Alert archive / Texas / Mesoscale Discussions in 2020

Mesoscale Discussion 1335

July 25, 202018 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Jul 25, 2020, 6:59 AM CDT for 18 counties in Texas. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued
Jul 25, 2020, 6:59 AM CDT (11:59 UTC)
Expired
Jul 25, 2020, 9:00 AM CDT
In force
2 hr
Issued by
the Storm Prediction Center
Concerning
Severe potential...watch possible
Chance of a watch
40%

Counties Aransas County, TX, Austin County, TX, Brazoria County, TX, Calhoun County, TX, Chambers County, TX, Colorado County, TX, DeWitt County, TX, Fort Bend County, TX, Galveston County, TX, Goliad County, TX, Harris County, TX, Jackson County, TX, Lavaca County, TX, Liberty County, TX, Matagorda County, TX, Refugio County, TX, Victoria County, TX, Wharton County, TX

The radar

The Houston radar (KHGX), 109 km from the middle of the area, began a volume at 12:04 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, 12.0 hours before the alert went out and 193 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 2020-07-25Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1066 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 2020-07-25The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 79 square meters per square second.1939Sfc1 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
1066 J/kg
Mixed-layer CIN
-37 J/kg
Mixed-layer LCL
1459 m above ground
0-6 km bulk shear
19 kt
0-1 km storm-relative helicity
79 m²/s²
0-3 km storm-relative helicity
67 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 25, 1:29 PM CDTMesoscale DiscussionSPCAransas, Bee, Brazoria, Calhoun, Fort Bend, Goliad and 6 more2 hr

Nearby

Mesoscale Discussions in Texas, 2020Every mesoscale discussion 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.