Thoughts on the New Year's Eve severe weather potential

A couple of observations on my part, then the latest statement from the National Weather Service concerning the metropolitan area... Looking at the latest information this morning, a few points stick out in my mind:

First, I believe the overall threat of tornadoes may be somewhat lower than expected yesterday. All of the ingredients, including the strongest dynamics and the greatest instability, don't quite seem to be phasing as well as I would like to see. This certainly does NOT rule out strong to severe thunderstorms capable of damaging wind or isolated large hail. In fact, I believe our main threat will be strong wind with storms near the cold front during the evening hours (see #3 below).

Second, I do not believe we'll see a prolonged rain event in the Mid-South during the day today, and possibly not this evening. Showers and thunderstorms will tend to be more scattered this afternoon, with any steady rain most likely just behind the front for a couple of hours. I expect that rain will be moving out by the time the guitar drops on Beale Street, ushering in 2011. This does not hold true for areas east of the immediate metro area, where a slower progression of the front could mean more rain for eastern portions of west TN and north and central MS.

Third, I expect to see the metro area near the north end of a developing squall line during the evening hours (between 5-9pm). The strongest storms should be over MS, where the heaviest rain will also fall. This line of storms could produce wind gusts in excess of 50 mph, or near severe limits, as it passes through the metro area during the evening (or roughly between the final horn at the Liberty Bowl and New Year's Eve festivities really ramping up).

Details and updated information will be available throughout the day on MemphisWeather.net, MWN on Twitter (@memphisweather1 and @shelbyalerts), and Facebook.


From the NWS:

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MEMPHIS TN
907 AM CST FRI DEC 31 2010

...SEVERE WEATHER LIKELY LATER TODAY ACROSS PORTIONS OF THE MID-SOUTH...

A STRONG STORM SYSTEM MOVING INTO THE AREA TODAY WILL SET THE STAGE FOR A SEVERE WEATHER EVENT ACROSS PORTIONS OF THE AREA. A WARM FRONT POSITIONED ACROSS CENTRAL ARKANSAS INTO NORTH CENTRAL MISSISSIPPI THIS MORNING WILL LIFT NORTHEAST TODAY. THE AIRMASS TO THE SOUTH OF THIS FRONT HAS BECOME WARM... HUMID... AND UNSTABLE. THIS UNSTABLE AIRMASS IS EXPECTED TO OVERSPREAD THE WESTERN HALF OF THE MID-SOUTH BY EARLY AFTERNOON PRIOR TO THE PASSAGE OF A STRONG COLD FRONT. THE INCREASED INSTABILITY COMBINED WITH STRONG ATMOSPHERIC WINDS WILL SET THE STAGE FOR SEVERE WEATHER ACROSS AREAS ALONG AND SOUTH OF THE WARM FRONT AND AHEAD OF THE COLD FRONT.

THE GREATEST SEVERE WEATHER RISK WILL EXIST ALONG AND WEST OF INTERSTATE 55 THIS AFTERNOON INTO EARLY EVENING... INCLUDING NORTHEAST AND EAST ARKANSAS... THE MISSOURI BOOTHEEL... SOUTHWEST TENNESSEE... AND NORTHWEST MISSISSIPPI. IN THESE LOCATIONS... SEVERE THUNDERSTORMS ARE EXPECTED TO DEVELOP BY EARLY THIS AFTERNOON AND MOVE QUICKLY EAST THROUGH THE EARLY EVENING HOURS. ANY SEVERE STORMS THAT DEVELOP WILL BE CAPABLE OF PRODUCING DAMAGING WINDS AND A FEW TORNADOES. THERE WILL BE A SECONDARY THREAT FOR LARGE HAIL. THE BEST TIMING FOR SEVERE WEATHER ACROSS THESE LOCATIONS WILL BE BETWEEN 2 PM CST AND 8 PM CST.

RESIDENTS ACROSS THE MID-SOUTH ARE URGED TO REMAIN UPDATED WITH THE LATEST FORECAST INFORMATION AND PLAN NOW FOR THE POTENTIAL OF SEVERE WEATHER THIS AFTERNOON AND EVENING. BE PREPARED TO SEEK SAFE SHELTER IN THE EVENT SEVERE WEATHER WARNINGS ARE ISSUED AND SEVERE WEATHER BECOMES IMMINENT.