Snow to increase over North Alabama
The Storm Prediction center warns that snow will be increasing over North Alabama. Lots of technical jargon in here…but I thought you would enjoy it…and bottom line is that increasing flow moving up and over the cold airmass over the South is leading to increasing snow rates, and they could approach an inch per hour over North Alabama.
MESOSCALE DISCUSSION 0014
NWS STORM PREDICTION CENTER NORMAN OK
0743 PM CST SUN JAN 09 2011
AREAS AFFECTED…ERN AR THROUGH NRN MS…NRN AL…SRN TN AND EXTREME
NWRN GA
CONCERNING…HEAVY SNOW
VALID 100143Z – 100645Z
SNOW RATES SHOULD GRADUALLY INCREASE THIS EVENING…INITIALLY OVER
ERN AR…SWRN TN AND NRN MS…THEN SPREADING NEWD INTO NRN AL…SRN
TN AND EXTREME NWRN GA WITH TIME. RATES LOCALLY FROM 0.5 TO 1 INCH
PER HOUR WILL BECOME POSSIBLE. SNOW MAY MIX WITH SLEET…ESPECIALLY
FORM NRN MS THROUGH NRN AL.
LARGE CP AIRMASS IS ENTRENCHED OVER THE SERN STATES WITH WET BULB
TEMPERATURES BELOW FREEZING. THE COLD AIR WILL LIKELY REMAIN DEEP
ENOUGH FOR MOSTLY SNOW FROM NRN MS…NRN AL INTO SRN TN THIS
EVENING. LARGE EXPANSE OF PRECIPITATION CONTINUES DEVELOPING NEWD
AND IS ASSOCIATED WITH WIDESPREAD ISENTROPIC ASCENT ABOVE THE POLAR
AIRMASS. WV IMAGERY SHOWS A COMPACT VORT MAX OVER THE LOWER MS
VALLEY. THIS FEATURE WILL DEAMPLIFY AS IT EJECTS NEWD TOWARD THE TN
VALLEY. ZONE OF STRONGER DEEP ASCENT WILL GRADUALLY SHIFT NEWD
THROUGH CNTRL AND NRN MS…NRN AL AND SRN TN IN ASSOCIATION WITH THE
VORT MAX AND ITS ATTENDANT 60 KT SLY LLJ. POTENTIAL FOR AREAS OF
HEAVIER SNOW INITIALLY EXISTS FROM ERN AR INTO NRN MS AND SWRN TN.
SNOW RATES WILL GRADUALLY INCREASE FARTHER NE INTO NRN AL…S-CNTRL
AND SERN TN LATER THIS EVENING AS AN INITIALLY DRY LAYER BELOW 3 KM
MOISTENS THROUGH THE PROCESS OF EVAPORATIVE COOLING. FORECAST
SOUNDINGS INDICATE A DEEP ISOTHERMAL LAYER DEVELOPING WITH
TEMPERATURES BETWEEN 0 AND -5C WHICH WILL AUGMENT SNOWFALL GROWTH
THROUGH AGGREGATION AS ZONE OF STRONGER ASCENT SHIFTS NEWD. SNOWFALL
MAY MIX WITH SLEET OVER A PORTION OF NRN MS AND NRN AL WHERE WARM
ADVECTION ALONG LLJ MIGHT CONTRIBUTE TO A WARM NOSE ABOVE THE
SUBFREEZING LAYER.
..DIAL.. 01/10/2011
Category: Alabama's Weather