MESO: Mesoscale Discussion 0821

ACUS11 KWNS 272035
SWOMCD
SPC MCD 272034
TXZ000-272130-

MESOSCALE DISCUSSION 0821
NWS STORM PREDICTION CENTER NORMAN OK
0334 PM CDT MON MAY 27 2013

AREAS AFFECTED...SE TX PANHANDLE SWWD INTO SW TX

CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE

VALID 272034Z - 272130Z

PROBABILITY OF WATCH ISSUANCE...60 PERCENT

SUMMARY...SVR TSTMS ARE EXPECTED TO DEVELOP ALONG THE DRYLINE THIS
AFTERNOON. WW WILL LIKELY BE NEEDED.

DISCUSSION...VISIBLE SATELLITE IMAGERY HAS SHOWN A GRADUAL INCREASE
IN CU ALONG AND JUST W OF THE DRYLINE FROM THE SE TX PANHANDLE SWWD
INTO SW TX. RADAR IMAGERY SHOWS WEAK RETURNS IN THE DRY AIR JUST E
OF LBB IN CROSBY COUNTY. TEMPERATURES ALONG AND JUST WEST OF THE
DRYLINE ARE IN THE MID 90S TO 100 AT CDS WHILE IN THE UPPER 80S AND
LOW 90S EAST. DEWPOINTS ARE IN THE LOW TO MID 60S AHEAD OF THE
DRYLINE. ALTHOUGH SOME BACKING OF WINDS HAS BEEN
OBSERVED...CONVERGENCE ALONG THE DRYLINE IS WEAK OVERALL. DESPITE
THIS LACK OF CONVERGENCE AND ABSENCE OF ANY NOTABLE LARGE SCALE
FORCING...THE VERY WARM TEMPERATURES FAVOR CONVECTIVE INITIATION
SOON. THE OVERALL LACK OF FORCING SHOULD ACT TO KEEP STORMS
DISCRETE.

AN UNSTABLE ENVIRONMENT EXISTS AHEAD OF THE DRYLINE AS STEEP
MID-LEVEL LAPSE RATES EXIST ATOP A MOIST BOUNDARY LAYER. RUC-BASED
SURFACE ANALYSIS INDICATES MLCAPE IN EXCESS OF 2000 J/KG AND
EFFECTIVE SHEAR AROUND 30 TO 40 KT. AS A RESULT...ROTATING SVR
STORMS ARE LIKELY. THERE IS SOME POTENTIAL FOR SIGNIFICANT WINDS AND
HAIL GIVEN THE UNSTABLE ENVIRONMENT... STEEP LOW-LEVEL LAPSE
RATES...AND LARGE TEMPERATURE-DEWPOINT SPREADS.

..MOSIER/MEAD.. 05/27/2013

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

ATTN...WFO...OUN...SJT...LUB...MAF...

LAT...LON 34290062 34620011 34499987 34129985 31650104 30030272
30550372 32740218 34290062

+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-
To unsubscribe from WX-STORM send e-mail to LISTSERV@LISTSERV.ILLINOIS.EDU with
"unsub wx-storm" in the body of your message. For more information write cnovy@cox.net.