000
ACUS11 KWNS 010414
SWOMCD
SPC MCD 010413
ILZ000-IAZ000-MOZ000-011015-

MESOSCALE DISCUSSION 0048
NWS STORM PREDICTION CENTER NORMAN OK
1013 PM CST SAT JAN 31 2015

AREAS AFFECTED...CNTRL AND SE IA...NE MO...NRN IL

CONCERNING...HEAVY SNOW

VALID 010413Z - 011015Z

SUMMARY...AREAS OF HEAVY SNOW ARE EXPECTED TO DEVELOP LATE THIS
EVENING THROUGH THE OVERNIGHT PERIOD ACROSS CNTRL IA...SE IA...NE MO
EWD INTO NRN IL. SNOWFALL RATES COULD REACH 1 INCH PER HOUR IN SOME
LOCATIONS WITHIN THE MCD AREA. DUE TO SFC TEMPS BEING NEAR
FREEZING...IMPACTS OF ANY HEAVY SNOWFALL SHOULD REMAIN LESSENED.

DISCUSSION...THE LATEST SFC ANALYSIS SHOWS A 1009 MB LOW OVER WCNTRL
KS WITH A QUASI-STATIONARY FRONTAL BOUNDARY EXTENDING FROM THE SFC
LOW ENEWD TO THE VICINITY OF OMAHA NEB AND DES MOINES IA. POCKETS OF
MODERATE SNOWFALL ARE ALREADY ONGOING ALONG AND SOUTH OF THE
BOUNDARY FROM SE NEB INTO SCNTRL IA AND FAR NRN MO. THIS IS IN
RESPONSE TO ISENTROPIC LIFT ASSOCIATED WITH LEFT EXIT REGION OF A 40
TO 50 KT LOW TO MID-LEVEL JET. THE HRRR SUGGESTS THIS FEATURE WILL
MOVE SLOWLY EWD ACROSS SE IA INTO NRN IL DURING THE OVERNIGHT PERIOD
HELPING TO ENHANCE SNOWFALL RATES. AS A RESULT...BANDS OF SNOW ARE
EXPECTED TO CONTINUE DEVELOPING IN CNTRL AND SRN IA...SPREADING
SLOWLY EWD INTO NRN IL OVER THE NEXT 2 TO 4 HOURS. ALTHOUGH SFC
TEMPS REMAIN JUST ABOVE FREEZING IN MANY LOCATIONS WITHIN THE MCD
AREA...TEMPS SHOULD FALL TO NEAR OR SLIGHTLY BELOW FREEZING AS
WET-BULBING AND DIURNAL COOLING OCCURS. SNOWFALL RATES COULD REACH
NEAR 1 INCH PER HOUR WITHIN THE HEAVIEST PARTS OF THE BANDS. THE
POTENTIAL IS EXPECTED TO INCREASE FROM WEST TO EAST WITH NRN IL
BEING IMPACTED AFTER MIDNIGHT. DUE TO THE RELATIVELY WARM SFC TEMPS
NEAR FREEZING...THE IMPACT OF ANY HEAVY SNOW SHOULD REMAIN LESSENED.

..BROYLES.. 02/01/2015

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...LOT...ILX...LSX...DVN...DMX...EAX...

LAT...LON   41008848 40578966 40139233 40349355 40879390 41629395
            42319323 42149116 41848878 41008848