[MCD] SWOMCD

[Mesoscale Convective Discussions]

ACUS11 KWNS 161116
SWOMCD
SPC MCD 161116 
WIZ000-ILZ000-IAZ000-MNZ000-MOZ000-161615-

MESOSCALE DISCUSSION 0145
NWS STORM PREDICTION CENTER NORMAN OK
0516 AM CST THU FEB 16 2006

AREAS AFFECTED...IA...EXTREME NRN MO...SERN MN...SRN THROUGH N CNTRL
WI AND NRN IL

CONCERNING...HEAVY SNOW AND SLEET 

VALID 161116Z - 161615Z

SNOW IS EXPECTED TO INCREASE IN COVERAGE AND INTENSITY FROM CNTRL
AND NRN IA THROUGH SERN MN AND MUCH OF SRN AND CNTRL WI. RATES MAY
INCREASE TO LOCALLY IN EXCESS OF 1 INCH PER HOUR. PRECIPITATION MAY
REMAIN MOSTLY SLEET AND FREEZING RAIN FROM SRN IA...NRN MO AND NRN
IL.

EARLY THIS MORNING A FRONT DEMARCATING THE LEADING EDGE OF ARCTIC
AIR EXTENDS FROM NRN IND SWWD THROUGH CNTRL MO AND INTO NWRN OK. A
SHORTWAVE TROUGH AND ATTENDANT MID LEVEL JET WILL EJECT NEWD THROUGH
THE CNTRL PLAINS AND UPPER MS VALLEY TODAY. ASSOCIATED STRONG SLY
LOW LEVEL JET WILL SHIFT ENEWD INTO THE MID MS VALLEY...CONTRIBUTING
TO NWD ADVECTION OF MOISTURE ABOVE THE LOW LEVEL BAROCLINIC ZONE.
THE INCREASING FRONTOGENETIC FORCING... ISENTROPIC LIFT AND MOISTURE
TRANSPORT RESULTING FROM THESE PROCESSES WILL CONTRIBUTE TO BANDS OF
HEAVY SNOW DEVELOPING FROM IA NEWD THROUGH WI THIS MORNING AND INTO
THE AFTERNOON. LAPSE RATES APPEAR STEEP ENOUGH TO SUPPORT SOME
CONVECTIVE ENHANCEMENT TO THE SNOW...ESPECIALLY FROM IA THROUGH S
CNTRL WI. RECENT LIGHTNING DATA ARE ALREADY SHOWING A FEW STRIKES
ACROSS SERN IA. FARTHER S FROM SRN IA...NRN MO AND NRN IL...SLEET
AND FREEZING RAIN WILL BE MORE LIKELY AS WARM ADVECTION ASSOCIATED
WITH THE LOW LEVEL JET CONTRIBUTES TO AN ABOVE FREEZING LAYER ABOVE
THE SURFACE.

..DIAL.. 02/16/2006

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

ATTN...WFO...GRB...LOT...MKX...DVN...ARX...MPX...DMX...EAX...FSD...OAX...

44518764 42698829 40749111 39739431 41559591 43349563
44849233 45388889 

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