SPC MD 268

MD 0268 CONCERNING HEAVY SNOW FOR EXTREME E-CNTRL/NERN NEB…WRN/CNTRL/NRN IA


MESOSCALE DISCUSSION 0268
NWS STORM PREDICTION CENTER NORMAN OK
0116 PM CDT SUN MAR 10 2013

AREAS AFFECTED...EXTREME E-CNTRL/NERN NEB...WRN/CNTRL/NRN IA

CONCERNING...HEAVY SNOW

VALID 101816Z - 102315Z

SUMMARY...HEAVY BAND OF SNOW ORIENTED SW-NE WITH RATES NEAR 1 IN/HR
IS FORECAST TO DEVELOP OVER EXTREME E-CNTRL/NERN NEB AND WRN IA BY
MID AFTERNOON. HEAVY SNOWFALL WILL THEN SPREAD ENEWD INTO CNTRL/NRN
IA DURING THE 21-03Z PERIOD.

DISCUSSION...WV IMAGERY AND RUC ANALYSIS SHOW A MIDLEVEL LOW
POSITIONED OVER NERN KS AT 18Z...WITH A DRY SLOT EXTENDING NWD INTO
NERN MO AS WELL AS FAR SWRN/S-CNTRL IA...AND A BAND OF MODERATE TO
HEAVY SNOWFALL EXTENDING FROM E-CNTRL NEB INTO S-CNTRL NEB/FAR
N-CNTRL KS. AS THE MIDLEVEL LOW SHIFTS NEWD TOWARD SRN PORTIONS OF
IA THROUGH THE AFTERNOON INTO THE EVENING...MIDLEVEL DEFORMATION
ZONE WILL STRENGTHEN FROM ERN NEB/WRN IA INTO CNTRL/NRN IA.
TEMPERATURE PROFILES WILL BE COLD ENOUGH FOR SNOW OVER WRN IA...AND
RATES ARE FORECAST TO APPROACH 1 IN/HR GIVEN MODERATE TO STRONG
UVV/S OCCURRING THROUGH THE DENDRITIC GROWTH ZONE. OVER
CNTRL/N-CNTRL AND NERN PORTIONS OF IA...LOW-LEVEL TEMPERATURE
PROFILES ARE CURRENTLY ABOVE FREEZING...WHICH WILL DELAY THE CHANGE
OVER TO SNOW UNTIL 21-03Z AS LOW-LEVEL CAA AND STRENGTHENING UVV/S
DEVELOP ACROSS THE AREA. ONCE THE TRANSITION TAKES PLACE...RATES
AROUND 1 IN/HR WILL BE POSSIBLE.

..GARNER.. 03/10/2013

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

ATTN...WFO...DVN...ARX...DMX...FSD...OAX...

LAT...LON   42589642 43389457 43379124 42829082 42329114 41969274
            41009582 41429656 42589642

via SPC Forecast Products http://www.spc.noaa.gov/products/md/md0268.html