Tennessee Valley Storm Trackers: Potential For Severe Wx Across Miss Including Tornadoes On New Years Eve.

Wednesday, December 29, 2010

Potential For Severe Wx Across Miss Including Tornadoes On New Years Eve.

Looking more an d more likely for some type of severe weather across portions of Mississippi
on Friday evening into the overnight hours to Saturday morning. Latest models show the bulk
storm activity will be after everyone has gone to bed although a few supercells could very
well develop anytime Friday Afternoon across the area. Below is the latest from NWS in Jackson.
As for Alabama it is to early to tell if we will see any severe wx. I am not to concerned with
That right now as models do not support it right now. We will see some thunder and a warning
or 2 is not out of the question, but gusty winds and heavy rain are the main threat.
The main tornado, high wind, and hail threat seem to be in Central to Southern Mississippi
Extending down into SW Alabama on Saturday. Stay tuned as we fine tune the forecast later.

THE MAIN FOCUS FOR THE
LONG TERM REMAINS THE POTENTIAL FOR SEVERE WEATHER FRIDAY AND FRIDAY
NIGHT. THERE ALSO REMAINS TIMING AND EVOLUTIONS DIFFERENCES WITH THE
FRIDAY SYSTEM. MODELS AGREE THOUGH THAT BY FRIDAY MORNING A DEEP
CLOSED LOW AND ASSOCIATED SUB 1000MB LOW WILL BE OVER THE CENTRAL
PLAINS. THIS SYSTEM WILL LIFT TO THE NORTHEAST ACROSS THE MID
MISSISSIPPI VALLEY FRIDAY AND OVER THE UPPER MISSISSIPPI RIVER
VALLEY FRIDAY NIGHT. THE ASSOCIATED COLD FRONT WILL APPROACH OUR CWA
FRIDAY AND ENTER OUR NORTHWEST ZONES EARLY FRIDAY EVENING. AHEAD OF
THE COLD FRONT A VERY STRONG AND SHEARED WIND FIELD IS EXPECTED TO
HELP INCREASE DEEP MOISTURE OVER OUR REGION. PWS ARE EXPECTED TO
RISE BETWEEN 1.25 AND 1.5 INCHES BY FRIDAY AFTERNOON WITH LOW TO MID
60 DEGREE SURFACE DEW POINTS BACK ACROSS THE CWA. COMPARED TO LAST
NIGHT'S RUN MODELS ARE SHOWING A LITTLE LESS INSTABILITY WITH THE
SYSTEM FRIDAY THAT BECOMES EVEN MORE LIMITED FROM NORTH TO SOUTH
TOWARD FRIDAY EVENING. STILL...CONSIDERING THE AVAILABLE MOISTURE...
STRONG DEEP LAYER SHEAR AND FORCING...THE POTENTIAL FOR SEVERE
WEATHER ALONG AND AHEAD OF THE FRONT FRIDAY INTO NEW YEARS DAY WILL
EXIST OVER OUR CWA. DISCRETE SEVERE STORMS WILL BE POSSIBLE FRIDAY
AHEAD OF THE COLD FRONT ESPECIALLY OVER OUR WEST THEN ALONG THE COLD
FRONT THROUGH THE NIGHT. THE MAIN THREATS STILL APPEAR TO BE
DAMAGING WINDS AND A FEW TORNADOES WITH LARGE HAIL AND HEAVY RAIN
SECONDARY. THE STORM PREDICTION CENTER HAS OUTLOOKED OUR CWA WITH A
SLIGHT RISK FRIDAY AND FRIDAY NIGHT. THE GFS STILL ENDS THE RAIN
MUCH EARLIER THAN THE ECMWF. A LARGE UPPER LEVEL TROUGH WILL REMAIN
TO OUR WEST PROVIDING SOUTHWEST FLOW ALOFT BUT A LARGE 1030MB HIGH
WILL MOVE OVER THE CENTRAL PLAINS AND HELP PUSH THE COLD FRONT SOUTH
OF OUR CWA. THE SREF LOOKED LIKE A GOOD COMPROMISE AND THE
SIGNIFICANT RAINFALL SHOULD END OVER OUR SOUTHEAST EARLY SATURDAY
MORNING. A MUCH COOLER AND DRIER AIRMASS WILL BE OVER OUR CWA BY
SATURDAY AFTERNOON. COOLER AND DRYER WEATHER IS EXPECTED THROUGH
MONDAY BUT THE GFS INSISTS ON BRINGING PCPN BACK INTO OUR CWA BY
TUESDAY MORNING WHILE THE ECMWF KEEPS US DRY UNTIL LATE WEDNESDAY.
BOTH MODELS MAINTAIN AND ACTIVE SOUTHERN BRANCH OF THE JET STREAM
WITH SUBTLE SHORTWAVES MOVING ACROSS OUR REGION IN THE SOUTHWEST
FLOW ALOFT. THE GFS MOVES THE SURFACE HIGH A LITTLE TOO FAST EAST OF
OUR REGION MONDAY ALLOWING FOR OVERRUNNING MOISTURE BACK ACROSS THE
OLD COLD FRONT TO RETURN INTO OUR CWA. WL CUT POPS MONDAY NIGHT
THROUGH WEDNESDAY AND LIMIT BEST CHANCES TO OUR SOUTHERN MOST ZONES.
/22/

NAM STP valid 00z Sat