Quantitative Precipitation Forecast
Issued by NWS

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FOUS11 KWBC 242045
QPFHSD

PROBABILISTIC HEAVY SNOW AND ICING DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
444 PM EDT TUE MAR 24 2015

VALID 00Z WED MAR 25 2015 - 00Z SAT MAR 28 2015


...FRONT RANGE OF THE ROCKIES AND UPPER MIDWEST TO THE GREAT
LAKES/NORTHEAST...

A SPLIT FLOW NEG TILT UPPER TROUGH WILL LIFT THROUGH THE PLAINS
AND UPPER MS VALLEY OVER THE NEXT 24 HRS TO PRODUCE A WIDE-ARRAY
OF FROZEN PRECIP ON WED BEFORE PHASING OVER ONTARIO ON THURS. THIS
SYSTEM WILL BE FOLLOWED BY ADDITIONAL UPSTREAM UPPER DYNAMICS
WHICH WILL GLIDE DOWN THE FRONT RANGE OF THE ROCKIES AND
BOTTOM-OUT IN THE BASE OF THE UPPER TROUGH BEFORE RIDING UP THE OH
RIVER INTO THE NORTHEAST. THIS COULD RESULT IN WIDESPREAD HEAVY
RAINFALL WITH THE BACK EDGE RESULTING IN SOME SNOW ACROSS THE
GREAT LAKES INTO NEW ENGLAND.

THE WINTER WEATHER THREAT OVER THE NEXT 24 HRS WILL BE
CONCENTRATED OVER THE UPPER MIDWEST. THE NRN STREAM LOW NEAR THE
ND/CANADIAN BORDER WILL GIVE WAY TO THE DEVELOPING SRN STREAM LOW
NEAR ERN KS/WRN MO. THIS SURFACE WAVE WILL LIFT OFF TO THE NORTH
AND EAST TOWARD MI... WHILE A WEALTH OF INCREASING MOISTURE
CONTENT BEGINS TO FLOURISH. OUT AHEAD OF THE SYSTEM... AN
IMPRESSIVE SURFACE RIDGE WILL ATTEMPT TO HANG ON ACROSS MN/WI INTO
IA/IL. DESPITE THE LARGE SCALE WARM ADVECTION... IT APPEARS THIS
POLAR AIR MASS WILL BE TOUGH TO SCOUR OUT... ESPECIALLY WITH THE
BATCH OF DYNAMIC COOLING SHIELD OF MOISTURE. THIS PLUME IS
CURRENTLY LOCATED OVER WRN IA AND SHOULD SLIDE NORTH AND EAST
THROUGH SERN MN/NRN IL AND MUCH OF WI INTO THE UP OF MI. THE
GUIDANCE IS RATHER UNANIMOUS ON A ZONE OF HEAVY SNOW AND POTENTIAL
ICING STRETCHING FROM SERN MN/NERN IA THROUGH WI INTO PARTS OF
UPPER MI. WPC GENERALLY FOLLOWED A MULTI-MODEL BLEND FOR THE HEAVY
SNOW AND ICING PROBS.

AS THE SYSTEM DEPARTS AND DEEPENS OVER ONTARIO... ADDITIONAL UPPER
DYNAMICS UPSTREAM WILL DIVE DOWN THE FRONT RANGE OF THE
NRN/CENTRAL ROCKIES FOR BRIEF UPSLOPE HEAVY SNOWS BEFORE ARRIVING
INTO THE SRN PLAINS/LOWER MS VALLEY. THIS WILL INDUCE A SURFACE
LOW WHICH WILL RIDE UP THE OH RIVER ON THURS BEFORE PRESSING
THROUGH THE NORTHEAST ON FRI. AN ANOMALOUS SURGE OF GULF OF MEXICO
MOISTURE WILL FLOURISH NORTH OF THE FRONTAL WAVE/ZONE INTO THE
COLD SECTOR BUT IT NOT UNTIL THURS MORNING WHERE THE STRONG COLD
ADVECTION COOLS THE COLUMN FOR RAIN CHANGING OVER TO SNOW FROM NRN
PA INTO UPSTATE NY. THEN ON FRI AS THE ENTIRE POST-FRONTAL PRECIP
SHIELD PROGRESSES THROUGH THE NORTHEAST EXPECT MORE LIGHT TO MDT
SNOW TOTALS ACROSS NEW ENGLAND. WPC GENERALLY FOLLOWED A
BLEND/COMPROMISE OF THE GFS/ECMWF FOR HEAVY SNOW PROBS.

MUSHER

$$




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