Quantitative Precipitation Forecast
Issued by NWS

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27
000
FOUS11 KWBC 282012
QPFHSD

PROBABILISTIC HEAVY SNOW AND ICING DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
411 PM EDT SAT MAR 28 2015

VALID 00Z SUN MAR 29 2015 - 00Z WED APR 01 2015


DAYS 1-3...

...SOUTHERN NEW ENGLAND...

THE AMPLIFIED ANOMALOUS UPPER TROUGH OVER THE ERN PORTION OF THE
COUNTRY WILL GRADUALLY PRESS EASTWARD/DOWNSTREAM ON SUN. HOWEVER
BEFORE THEN... THE CYCLOGENESIS TAKING PLACE EAST OF NEW ENGLAND
WILL SLIDE OFF TO THE NORTH AND EAST. THIS WILL ELONGATE THE
TROWAL AND TRANSITION THE MAIN DEFORMATION ZONE OFFSHORE OF SERN
NEW ENGLAND. MEANWHILE... A MID TO UPPER CIRCULATION WILL SLIDE
FROM ERN PA TO JUST OFFSHORE OF COASTAL NEW ENGLAND OVERNIGHT SAT
INTO SUN MORNING AND ENOUGH VERTICAL VELOCITIES WILL INTERACT WITH
WHAT IS LEFT IN MOISTURE CONTENT FOR ONE LAST BURST OF LIGHT TO
MDT SNOW ACROSS PARTS OF SRN NEW ENGLAND.

...GREAT LAKES TO NORTHERN NEW ENGLAND...

A RATHER PRONOUNCED MARITIME SHORT WAVE TROUGH WILL MESH WITH THE
POLAR JET TO ADVANCE INTO THE UPPER MS VALLEY/GREAT LAKES ON SUN
BEFORE SWEEPING THROUGH THE NERN CORRIDOR OF THE COUNTRY ON MON.
WARM ADVECTION PRECIPITATION AHEAD OF THE SHORTWAVE TROUGH MOVING
THROUGH THE UPPER MIDWEST SUN MORNING...FOLLOWED BY FAVORABLE
UPPER JET DYNAMICS NEAR THE TRIPLE POINT SURFACE LOW AND ENDING
WITH LAKE EFFECT SHOWS MAY CONTRIBUTE TO SOME LOCALLY HEAVY SNOW
ACCUMULATIONS ACROSS NORTHERN MI BUT THE BULK OF THE HEAVY
SNOWFALL WILL OCCUR UP IN ONTARIO. THE WARM ADVECTION
PRECIPITATION WILL TRANSITION DOWNSTREAM TO REACH THE ERN LAKES
INTO NEW ENGLAND ON MON... FOLLOWED BY SOME LAKE ENHANCEMENT. THIS
MAY PRODUCE SOME LOCALLY HEAVY AMOUNTS IN THE EASTERN LEE OF LAKES
ONTARIO/ERIE INTO NRN NEW ENGLAND BUT A CONSIDERABLE DRY SLOT
SHOULD KEEP AMOUNTS MINIMAL.

...UPPER MS VALLEY INTO GREAT LAKES...

ON THE HEELS OF THE SEMI-PHASED POLAR/MARITIME SHORT WAVE TROUGH
WILL BE ANOTHER LESS AMPLIFIED AND PROGRESSIVE SHORT WAVE IMPULSE
ON TUES. THIS FEATURE WILL RACE DOWNSTREAM WITH A SURFACE WAVE
TRACKING FROM SRN MN TO SRN LAKE MI TO WV MON EVENING TO TUES
EVENING. SURFACE HIGH PRESSURE SPRAWLED OVER THE SRN TIER OF THE
COUNTRY WILL PROHIBIT A SIGNIFICANT AMOUNT OF MOISTURE TO INTERACT
WITH THE DISTURBANCE. THUS EXPECT A NARROW ZONE OF DYNAMIC FORCING
FOR A STREAK OF LIGHT TO MDT SNOW FROM NERN MN/UP OF MI TO SWRN
NY/NWRN PA BUT NO HEAVY SNOW PROBS WILL BE CARRIED GIVEN THE MODEL
SPREAD AT THE MOMENT.

THE PROBABILITY OF SIGNIFICANT ICING IS LESS THAN 10 PERCENT.

MUSHER

$$




USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.