MESOSCALE DISCUSSION 0063
NWS STORM PREDICTION CENTER NORMAN OK
0108 AM CST MON FEB 02 2004
AREAS AFFECTED...NERN MO/SERN IA AND MUCH OF CENTRAL IL
CONCERNING...FREEZING RAIN
VALID 020708Z - 021115Z
FREEZING RAINFALL RATES RANGING FROM 0.05-0.10 INCHES PER 3 HOURS IS
EXPECTED TO SPREAD NWD ACROSS MUCH OF CENTRAL IL AND EXTREME NERN MO
INTO EXTREME SERN IA DURING THE NEXT 2-3 HOURS...REACHING PORTIONS
OF NWRN IL/FAR EAST CENTRAL IA BY 10Z.
REGIONAL RADARS SHOW A LARGE AREA OF RAINFALL MOVING NWD ACROSS ERN/
SERN MO AND SWRN IL WITH RAINFALL RATES AROUND 0.03 IN/HR. THIS
ACTIVITY IS ASSOCIATED WITH LOW-LEVEL WAA AS A SLY 40 KT LLJ
INDICATED BY VWP DATA AT STL/MEM/PAH...NOSES INTO THIS REGION. 00Z
SOUNDINGS FROM ERN IA/CENTRAL IL SHOWED DRY LOW-MID LEVELS WITH
CURRENT SURFACE WET-BULB TEMPERATURES ACROSS THE AREA OF CONCERN IN
THE MID-UPPER 20S. LARGE SCALE ASCENT WILL INCREASE AS THE SRN
PLAINS UPPER TROUGH BECOMES NEGATIVELY TILTED AND BEGINS TO LIFT
NEWD TOWARD THE MID MS VALLEY DURING THE NEXT 6-12 HOURS. THIS
ASCENT COMBINED WITH PERSISTENT LOW-LEVEL WAA WILL PROVE SUFFICIENT
TO MOISTEN THE BOUNDARY LAYER...RESULTING IN A PERIOD OF FREEZING
RAIN CONTINUING THROUGH THE MORNING /BEYOND 12Z/.
..PETERS.. 02/02/2004
ATTN...WFO...LOT...ILX...LSX...DVN...
39348976 39499131 40619179 41949044 41008868 40458790
39778782 39418818
|