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
000
FOUS11 KWBC 222047
QPFHSD

PROBABILISTIC HEAVY SNOW AND ICING DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
347 PM EST WED NOV 22 2017

VALID 00Z THU NOV 23 2017 - 00Z SUN NOV 26 2017


DAYS 1-3...

...PACIFIC NORTHWEST/NORTHERN ROCKIES...

WITH A STRONG UPPER RIDGE IN PLACE OVER THE WESTERN U.S....SNOW
LEVELS WILL REMAIN HIGH...WITH LITTLE TO NO THREAT FOR HEAVY SNOWS
EXPECTED AWAY FROM THE HIGHEST PEAKS OF THE NORTHERN CASCADES
THROUGH THURSDAY.  A WELL-DEFINED SHORTWAVE TROUGH IS FORECAST TO
MOVE ONSHORE THE PACIFIC NORTHWEST LATE THURSDAY AND ACROSS THE
NORTHERN ROCKIES THROUGH EARLY FRIDAY. SNOW LEVELS WILL COME DOWN
ACROSS THE PACIFIC NORTHWEST AND NORTHERN ROCKIES WITH THE ARRIVAL
OF A COLDER AIR MASS BEHIND THE SHORTWAVE. LIGHT TO MODERATE
SNOWFALL WILL BE POSSIBLE ACROSS THE NORTHERN ROCKIES WITH THE
PASSING SHORTWAVE.  HEAVIEST ACCUMULATIONS ARE FORECAST TO FALL
ALONG THE NORTHERN WASHINGTON CASCADES WHERE WPC DAY 2
PROBABILITIES SHOW A MODERATE RISK FOR ACCUMULATIONS OF 8-INCHES
OR MORE AND A SLIGHT RISK FOR ACCUMULATIONS OF A FOOT OR MORE FOR
THE WESTERN SLOPES ABOVE 4000 FT.  PRECIPITATION IS EXPECTED TO
WANE ON FRI AND SNOW LEVELS ARE FORECAST TO LIFT ONCE AGAIN AS THE
UPPER TROUGH PROGRESSES QUICKLY TO THE EAST...WITH THE RIDGE
QUICKLY REBUILDING IN ITS WAKE.

...NORTHERN MAINE...

LOW PRESSURE WELL OFF THE MID ATLANTIC COAST WILL INTERACT WITH A
COLD FRONT PUSHING ACROSS THE NORTHEAST TO RAPIDLY DEVELOP LATE
WEDNESDAY NIGHT. THE SURFACE LOW WILL BOMB OUT AND BEGIN TO GAIN
LATITUDE TOWARD THE CANADIAN MARITIMES WITH PRECIPITATION
DEVELOPING AND WRAPPING AROUND THE LOW BACK INTO MAINE. THE RAPID
DEVELOPMENT WILL BE TOO FAR EAST TO BRING A HEAVY SNOW THREAT TO
MAINE BUT IT SHOULD BRING THE POTENTIAL FOR AT LEAST A LIGHT
ACCUMULATION TO NORTHERN MAINE BEFORE RACING OFF TO THE NORTHEAST.

FOR DAYS 1-3...THE PROBABILITY OF SIGNIFICANT ICING IS LESS THAN
10 PERCENT.

KREKELER

$$





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