Sunday, January 22, 2012

Mesoscale Discussion #45 (Tornado Potential Increasing for Arkansas, Louisiana)



MESOSCALE DISCUSSION 0045 NWS STORM PREDICTION CENTER NORMAN OK 0226 PM CST SUN JAN 22 2012 AREAS AFFECTED...NERN TX...NRN LA...SRN/ERN AR...NWRN MS...WRN TN CONCERNING...SEVERE POTENTIAL...TORNADO WATCH LIKELY VALID 222026Z - 222230Z SEVERE THUNDERSTORMS SHOULD INITIATE BY EARLY EVENING NEAR THE ARKLATEX THEN RACE NEWD TOWARD WRN TN/NWRN MS AFTER DARK. DAMAGING WINDS AND ISOLATED TORNADOES ARE EXPECTED. A TORNADO WATCH WILL LIKELY BE REQUIRED BY 00Z. LEADING EDGE OF WELL DEFINED UPPER TROUGH IS ADVANCING ACROSS ERN OK/NERN TX AND WILL SOON OVERSPREAD THE LOWER MS VALLEY. IN ADVANCE OF THIS FEATURE...WARM MOIST BOUNDARY LAYER HAS SPREAD INTO SRN/ERN AR...AS NOTED BY SFC DEW POINTS RISING THROUGH THE UPPER 50S INTO THE 60S...WHILE A STUBBORN WEDGE OF COOLER AIR HAS YET TO BE DISPLACED OVER MUCH OF CNTRL/NWRN AR. CURRENT THINKING IS GREATEST AIRMASS DESTABILIZATION WILL OCCUR TO THE S-E OF THE AFOREMENTIONED WEDGE FRONT AND THIS WILL BE THE CORRIDOR OF GREATEST SEVERE THUNDERSTORM POTENTIAL. LATEST VIS IMAGERY DEPICTS AN INCREASING BAND OF LOW LEVEL CU ALONG THE DRY LINE NEAR I-35 OVER NCNTRL TX. THIS IS ALONG THE LEADING EDGE OF STEEPER LAPSE RATES AND IS CERTAINLY INDICATIVE OF STRONGER FORCING THAT WILL SOON OVERSPREAD THE ARKLATEX. WITH TIME THUNDERSTORMS COULD EVOLVE ALONG THIS LINE...OR PERHAPS EVEN DEVELOP WELL AHEAD OF THE WIND SHIFT WITHIN DEEPER CONFLUENT ZONE NEAR THE LA BORDER AS EXHIBITED BY SHOWERS BEGINNING TO DEEPEN FROM NEAR TYR TO JUST WEST OF SHV. NEEDLESS TO SAY VERY STRONG SHEAR WILL SUPPORT SUPERCELL DEVELOPMENT AND THE POTENTIAL FOR TORNADOES.

2 comments:

Mike Paulocsak said...

Hello Andrew.I would say this is quite early for an outbreak of severe weather like this so early in the year,wouldn't you say so?I guess all the conditions are favorable.

Andrew said...

It is indeed very early for a tornado outbreak.