Alert archive / Texas / Mesoscale Discussions in 2011

Mesoscale Discussion 237

March 19, 201135 counties in Texas

The Storm Prediction Center issued this mesoscale discussion at Mar 19, 2011, 3:20 PM CDT for 35 counties in Texas. It was in force for 85 min.

The area

The outline as issued.

The facts

Issued
Mar 19, 2011, 3:20 PM CDT (20:20 UTC)
Expired
Mar 19, 2011, 4:45 PM CDT
In force
85 min
Issued by
the Storm Prediction Center
All 35 counties

Andrews County, TX, Bailey County, TX, Borden County, TX, Briscoe County, TX, Castro County, TX, Cochran County, TX, Crane County, TX, Crosby County, TX, Dawson County, TX, Dickens County, TX, Ector County, TX, Fisher County, TX, Floyd County, TX, Gaines County, TX, Garza County, TX, Glasscock County, TX, Hale County, TX, Hockley County, TX, Howard County, TX, Kent County, TX, Lamb County, TX, Lubbock County, TX, Lynn County, TX, Martin County, TX, Midland County, TX, Mitchell County, TX, Motley County, TX, Pecos County, TX, Reagan County, TX, Scurry County, TX, Swisher County, TX, Terry County, TX, Upton County, TX, Winkler County, TX, Yoakum County, TX

The radar

The Midland/Odessa radar (KMAF), 72 km from the middle of the area, began a volume at 20:24 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

The nearest sounding before it

Midland Regional, TX (KMAF), launched 12:00Z, 8.3 hours before the alert went out and 72 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, Midland Regional, TX at 12:00Z on 2011-03-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 729 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, Midland Regional, TX at 12:00Z on 2011-03-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 329 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
729 J/kg
Mixed-layer CIN
-307 J/kg
Mixed-layer LCL
816 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
329 m²/s²
0-3 km storm-relative helicity
362 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.7

Open this sounding in Storm Lab

The text

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

837 
ACUS11 KWNS 192020
SWOMCD
SPC MCD 192020 
TXZ000-NMZ000-192145-

MESOSCALE DISCUSSION 0237
NWS STORM PREDICTION CENTER NORMAN OK
0320 PM CDT SAT MAR 19 2011

AREAS AFFECTED...PORTIONS OF W TX...EXTREME SERN NM

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 

VALID 192020Z - 192145Z

THE POTENTIAL FOR ISOLATED SEVERE THUNDERSTORMS IS INCREASING ACROSS
PORTIONS OF WRN TX AND FAR SERN NM...WITH LARGE HAIL AND DAMAGING
WINDS THE PRIMARY THREATS. HOWEVER...THE ANTICIPATED CONVECTIVE
COVERAGE IS TOO SPARSE TO WARRANT A WW ATTM.

STRONG HEATING AND AMBIENT LOW-LEVEL MOISTURE CONTINUE TO YIELD A
NORTH-SOUTH ZONE OF INCREASING INSTABILITY EAST OF A DRYLINE
EXTENDING FROM NEAR HOB TO THE UNITED STATES/MEXICO BORDER 40 MILES
WSW OF 6R6...AND SOUTH OF A STATIONARY BOUNDARY DRAPED ACROSS
PORTIONS OF THE SOUTH PLAINS. WITHIN THIS REGION...RECENT RUC
MESOANALYSIS DEPICTS MLCAPE VALUES FROM 1000 TO 1500 J/KG...HIGHEST
NEAR THE INTERSECTION OF THE DRYLINE AND STATIONARY FRONT SOUTHEAST
OF HOB /WHERE LITTLE CONVECTIVE INHIBITION IS NOTED/.

RECENT CU DEVELOPMENT HAS BEEN NOTED IN VISIBLE SATELLITE IMAGERY
OVER THE HIGHER TERRAIN OF FAR WRN TX /INCLUDING THE DAVIS
MOUNTAINS/...WHERE THE STRONG INSOLATION HAS RESULTED IN 0-3-KM
LAPSE RATES APPROACHING DRY ADIABATIC. IT IS POSSIBLE THAT THIS
CONVECTION COULD BE STEERED INTO THE GREATER/DEEPER MOISTURE EAST OF
THE DRYLINE...WHERE IT COULD DEEPEN AND BECOME SEVERE. FARTHER
NORTH...INCREASING SFC CONVERGENCE NEAR THE FRONT/DRYLINE
INTERSECTION COULD SUPPORT CONVECTIVE INITIATION OVER THE NEXT FEW
HOURS...AND SFC PRESSURE FALLS ASSOCIATED WITH A MID-LEVEL WAVE HAVE
RECENTLY BEEN NOTED IN THIS REGION. THIS THREAT FOR CONVECTION COULD
EXTEND FARTHER NORTH INTO NWRN TX AS THE FRONT RETREATS NWD IN
RESPONSE TO DISSIPATING LOW-LEVEL STRATOCU.

EFFECTIVE BULK SHEAR MAGNITUDES OF 35 TO 45 KT AND STEEP MID-LEVEL
LAPSE RATES WILL PROMOTE ORGANIZED /POTENTIALLY SUPERCELLULAR/ STORM
STRUCTURES...WITH AN ATTENDANT THREAT FOR LARGE HAIL. ALONG AND
SOUTH OF THE RETREATING FRONT...STEEPER LOW-LEVEL LAPSE RATES COULD
ENHANCE THE DAMAGING WIND THREAT. HOWEVER...THE ABSENCE OF STRONGER
DEEP-LAYER FORCING WILL LIKELY PRECLUDE GREATER CONVECTIVE COVERAGE.
THUS...A WW IS NOT CURRENTLY ANTICIPATED.

..COHEN.. 03/19/2011

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...SJT...LUB...MAF...ABQ...

LAT...LON   34300028 32870026 32280089 31300149 30610169 30310230
            30630273 31160286 32450327 33570339 34420301 34690171
            34300028

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Mar 19, 7:30 AM CDTMesoscale DiscussionSPCArmstrong, Carson, Collingsworth, Donley, Gray, Hansford and 10 more60 min
Mar 19, 5:45 PM CDTSevere Thunderstorm WatchSPCBorden, Briscoe, Childress, Cottle, Crosby, Dawson and 18 more5 hr

Nearby

Mesoscale Discussions in Texas, 2011Every mesoscale discussion in 2011

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.