Mesoscale Discussion 281

Issued

Mar 26, 2011, 4:33 PM CDT (21:33 UTC)

Expired

Mar 26, 2011, 5:30 PM CDT

In force

57 min

Issued by

the Storm Prediction Center

The Ft Hood radar (KGRK), 156 km from the middle of the area, began a volume at 21:33 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.

476 
ACUS11 KWNS 262133
SWOMCD
SPC MCD 262133 
ARZ000-LAZ000-TXZ000-262230-

MESOSCALE DISCUSSION 0281
NWS STORM PREDICTION CENTER NORMAN OK
0433 PM CDT SAT MAR 26 2011

AREAS AFFECTED...PARTS OF ERN TX...NWRN LA AND SWRN AR

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE 

VALID 262133Z - 262230Z

PARTS OF ERN TX INTO NWRN LA/SWRN AR ARE BEING MONITORED FOR A
POSSIBLE SEVERE TSTM WATCH ISSUANCE LATE THIS AFTERNOON.

REGIONAL RADAR IMAGERY/LIGHTNING DATA SHOWED A COUPLE OF STRONGER
TSTMS HAD DEVELOPED SINCE 20Z OVER SOUTH CENTRAL TX /THE COUNTIES OF
BANDERA TO BLANCO AND TRAVIS/.  SO FAR...HAIL PRODUCED BY THESE
STORMS HAVE BEEN SUB-SEVERE.  IN ADDITION...VISIBLE SATELLITE
IMAGERY SHOWED CU/TCU DEVELOPING ALONG A DRY LINE EXTENDING SWWD
FROM EXTREME SWRN AR INTO SOUTH CENTRAL TX...JUST WEST OF THE
AFOREMENTIONED STORMS.  OBJECTIVE ANALYSES INDICATED STRONGER DEEP
MOISTURE CONVERGENCE OVER NERN TX AND SOUTH CENTRAL TX WHERE CU
APPEARS TO HAVE GREATER VERTICAL DEVELOPMENT.  

THE AIR MASS ALONG AND EAST OF THE DRY LINE IS MODERATELY UNSTABLE
/MLCAPE 1500-2500 J PER KG/...WITH EFFECTIVE BULK SHEAR 40-50 KT
ORIENTED PERPENDICULAR TO THE DRY LINE SUPPORTIVE FOR ORGANIZED
ROTATING UPDRAFTS.  DESPITE THE FAVORABLE THERMODYNAMICS AND DEEP
LAYER SHEAR...WEAK LOW LEVEL WINDS EAST OF THE DRY LINE AND GIVEN
THAT THE FLOW IS VEERED IS BOTH LIMITING CONVERGENCE AND OVERALL LOW
LEVEL SHEAR FOR A TORNADO THREAT.  HOWEVER...ANY STORM THAT CAN
BECOME SUSTAINED WILL HAVE THE POTENTIAL TO PRODUCE ISOLATED HAIL
AND STRONG WIND GUSTS.  FURTHER LIMITATION FOR GREATER TSTM COVERAGE
IS THE APPARENT LACK OF MID-UPPER LEVEL FORCING.

..PETERS.. 03/26/2011

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

ATTN...WFO...LZK...LCH...SHV...HGX...FWD...EWX...

LAT...LON   29669955 30809773 31989641 33319488 33749412 33519297
            33029288 31869298 29969505 29339664 29249824 29669955

Mesoscale Discussions in Texas, 2011Mesoscale Discussions in Louisiana, 2011Mesoscale Discussions in Arkansas, 2011Every mesoscale discussion in 2011

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.