Good day everyone!
URGENT WEATHER STATEMENT:
Public Severe Weather Outlook (PWO):
PUBLIC SEVERE WEATHER OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1057 AM CST THU FEB 20 2014
…A SIGNIFICANT SEVERE WEATHER EPISODE IS EXPECTED OVER PARTS OF THE LOWER OHIO VALLEY, TENNESSEE VALLEY INTO LOWER MISSISSIPPI VALLEY THIS AFTERNOON AND TONIGHT…
The NWS Storm Prediction Center in Norman, OK is forecasting the development of widespread damaging winds and a few tornadoes over parts of the lower Ohio and Tennessee Valleys, into the lower Mississippi Valley and central Gulf States this afternoon and tonight. The areas most likely to experience this activity include: Northwest Alabama Western and central Kentucky Northern Mississippi Western and middle Tennessee Elsewhere, severe storms are also possible from the Ohio Valley to central Gulf Coast. A storm system near Kansas City as of late morning will strengthen rapidly while moving toward Wisconsin this evening, as a cold front sweeps eastward across Missouri and Arkansas this afternoon. Along and ahead of the cold front, or more bands of severe thunderstorms are expected to develop by mid afternoon, initially along a line from Saint Louis to Texarkana. Storms will then spread eastward across the Ohio, Tennessee, and Mississippi Valleys through tonight. Widespread damaging thunderstorm winds are expected as storms evolve into a squall line by this evening and continue into the overnight hours. A few tornadoes will also be possible with storms embedded in or ahead of the squall line, mainly this afternoon into early tonight. State and local emergency managers are monitoring this developing situation. Those in the threatened area are urged to review severe weather safety rules and to listen to radio, television, and NOAA Weather Radio for possible watches, warnings, and statements later today
. ..Thompson.. 02/20/2014
Based on my analysis of Upper Air Soundings around the risk areas from 12Z, sounding data was pretty inconclusive as far as showing an unstable environment at that time. However, with daytime heating and quick advancement of the system, various severe weather parameter indices are forecast to increase by mid to late afternoon over the risk areas (i.e Lifted Indices of -2 to -4, CAPE approaching close to 1000 j/kg over some portions, increasing SRH and EHI, increase in SFC THETA-e, etc).
Given this situation, the Storm Prediction Center, Norman OK. has elevated a portion of the SLIGHT risk area, to a MEDIUM risk for Severe Thunderstorms today.
Based on forecast analysis of Severe Weather Parameters and Indices both from the SPC SREF model, and F5 DATA Severe Weather Software, blending the GFS and NAM outputs, the following indicates where the greatest probability severe weather should occur (circled in blue), and the probability of isolated tornadoes within the squall line (circled in red). This is NOT a GUARANTEE of 100% occurrence, however output of where the HIGHEST probability may very well occur.
I say this as, in some areas, ALL of the parameters required for tornadic activity ARE not merging together all in one area, however certain types of energy are available for initiating rotating cells within a severe line of storms. Hence, the main threat appears to be damaging straight line severe thunderstorm winds, with the probability of isolated tornadoes.
Residents within the risk areas should monitor NOAA Weather Radio, Local NWS office statements, and local weather through your preferred media outlet.
ALL of the following displays are linked…please click on them regularly for current information on watches, warnings and statements.
Stay safe, and have a blessed day!
T. F. “STORM” WALSH III
GMCS, USCG (ret)
METEOROLOGIST / HURRICANE SPECIALIST
MEMBER WEST CENTRAL FL AMS
CERTIFIED SKYWARN OFFICIAL STORM SPOTTER (advanced)