Alert archive / Texas / Mesoscale Discussions in 2015

Mesoscale Discussion 483

April 27, 201528 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Apr 27, 2015, 3:29 PM CDT for 28 counties in Texas. It was in force for 91 min.

The area

The outline as issued.

The facts

Issued
Apr 27, 2015, 3:29 PM CDT (20:29 UTC)
Expired
Apr 27, 2015, 5:00 PM CDT
In force
91 min
Issued by
the Storm Prediction Center
Chance of a watch
60%
All 28 counties

Austin County, TX, Bastrop County, TX, Bell County, TX, Bosque County, TX, Brazos County, TX, Burleson County, TX, Coryell County, TX, Ellis County, TX, Falls County, TX, Fayette County, TX, Freestone County, TX, Grimes County, TX, Hamilton County, TX, Hill County, TX, Hood County, TX, Johnson County, TX, Lee County, TX, Leon County, TX, Limestone County, TX, Madison County, TX, McLennan County, TX, Milam County, TX, Navarro County, TX, Robertson County, TX, Somervell County, TX, Travis County, TX, Washington County, TX, Williamson County, TX

The radar

The Ft Hood radar (KGRK), 66 km from the middle of the area, began a volume at 20:31 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

Fort Worth, TX (KFWD), launched 12:00Z, 8.5 hours before the alert went out and 178 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, Fort Worth, TX at 12:00Z on 2015-04-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2 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, Fort Worth, TX at 12:00Z on 2015-04-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 221 square meters per square second.1939587897Sfc1 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
2 J/kg
Mixed-layer CIN
-454 J/kg
Mixed-layer LCL
931 m above ground
0-6 km bulk shear
73 kt
0-1 km storm-relative helicity
221 m²/s²
0-3 km storm-relative helicity
158 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 26, 7:10 PM CDTMesoscale DiscussionSPCArcher, Baylor, Carson, Childress, Clay, Collingsworth and 14 more65 min
Apr 26, 7:59 PM CDTSevere Thunderstorm WatchSPCBandera, Bexar, Blanco, Brown, Burnet, Coleman and 24 more6 hr
Apr 26, 9:29 PM CDTMesoscale DiscussionSPCDallas, Ellis, Hood, Hunt, Johnson, Kaufman and 4 more91 min
Apr 26, 10:45 PM CDTTornado WatchSPCAnderson, Bell, Bosque, Comanche, Coryell, Ellis and 19 more5 hr
Apr 27, 12:49 AM CDTMesoscale DiscussionSPCAnderson, Angelina, Atascosa, Austin, Bastrop, Bexar and 49 more86 min
Apr 27, 1:27 AM CDTTornado WatchSPCAngelina, Atascosa, Austin, Bastrop, Bee, Brazos and 50 more6 hr
Apr 27, 3:42 AM CDTMesoscale DiscussionSPCArcher, Baylor, Clay, Cooke, Denton, Foard and 12 more93 min
Apr 27, 4:56 AM CDTMesoscale DiscussionSPCAngelina, Chambers, Hardin, Harris, Jasper, Jefferson and 13 more2 hr
Apr 27, 5:25 AM CDTMesoscale DiscussionSPCBrooks, Kenedy95 min
Apr 27, 6:01 AM CDTTornado WatchSPCJefferson, Orange7 hr
Apr 27, 1:08 PM CDTMesoscale DiscussionSPCAngelina, Chambers, Hardin, Jasper, Jefferson, Liberty and 9 more97 min

Nearby

Mesoscale Discussions in Texas, 2015Every mesoscale discussion in 2015

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.