807
FXUS01 KWBC 180740
PMDSPD
SHORT RANGE FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
239 AM EST WED DEC 18 2024
VALID 12Z WED DEC 18 2024 - 12Z FRI DEC 20 2024
...CLIPPER SYSTEM TO BRING PERIODS OF MODERATE TO HEAVY SNOW AND
GUSTY WINDS TO THE NORTHERN PLAINS AND UPPER MIDWEST/GREAT LAKES
THE NEXT COUPLE OF DAYS...
...SHOWERS AND STORMS CONTINUE INTO THE DAY WEDNESDAY FOR THE
OHIO/TENNESSEE VALLEYS WITH SOME LOCALLY HEAVY RAINFALL AND
ISOLATED FLASH FLOODING POSSIBLE...
...WELL ABOVE AVERAGE TEMPERATURES CONTINUE FOR MUCH OF THE LOWER
48...
LOWER ELEVATION/COASTAL RAIN AND HIGHER ELEVATION SNOW WILL LINGER
INTO THE EARLY MORNING HOURS WEDNESDAY OVER THE PACIFIC NORTHWEST
AND NORTHERN GREAT BASIN/ROCKIES AS AN UPPER-LEVEL WAVE DEPARTS
THE REGION. THE WAVE WILL THEN PASS OVER THE NORTHERN HIGH PLAINS,
LEADING TO LEE CYCLOGENESIS AND THE ORGANIZATION OF A CLIPPER
SYSTEM THAT WILL DROP EAST-SOUTHEASTWARD OVER THE PLAINS AND
MIDWEST THE NEXT COUPLE OF DAYS. STRENGTHENING MOIST SOUTHERLY
FLOW OVER COLDER AIR TO THE NORTH WILL BRING AN INTENSIFYING BAND
OF SNOW TO THE NORTHERN PLAINS WEDNESDAY EVENING AND INTO THE
OVERNIGHT HOURS. WINTER STORM WATCHES HAVE BEEN ISSUED FOR
NORTHERN AND EASTERN NORTH DAKOTA AND NORTHWESTERN MINNESOTA WHERE
3-6 INCHES OF SNOW, LOCALLY HIGHER, CAN BE EXPECTED. A WINTRY MIX
WILL BE POSSIBLE TO THE SOUTH OF THE HEAVIEST SNOW WITH SOME SNOW
AND LIGHT ICE ACCRETIONS POSSIBLE FROM EASTERN MONTANA
SOUTHEASTWARD THROUGH WESTERN NORTH DAKOTA AND INTO EASTERN SOUTH
DAKOTA. IN ADDITION, VERY STRONG, GUSTY WINDS ARE EXPECTED ACROSS
THE NORTHERN ROCKIES AND HIGH PLAINS WEDNESDAY INTO THURSDAY. THIS
WILL LEAD TO BLOWING SNOW AND LOW VISIBILITY WHERE SNOW IS EITHER
FALLING OR REMAINS ON THE GROUND. THE SYSTEM WILL PASS THROUGH THE
UPPER MIDWEST/GREAT LAKES THURSDAY, BRINGING SOME MODERATE TO
LOCALLY HEAVY SNOWFALL, PARTICULARLY ACROSS PORTIONS OF NORTHERN
WISCONSIN.
SHOWERS AND THUNDERSTORMS CONTINUE THIS MORNING AHEAD OF A COLD
FRONT STRETCHING FROM THE OHIO VALLEY SOUTHWEST THROUGH THE
TENNESSEE/LOWER MISSISSIPPI VALLEYS AND INTO THE SOUTHERN PLAINS.
SOME LOCALLY HEAVY RAINFALL IS EXPECTED ACROSS THE OHIO AND
TENNESSEE VALLEYS WHERE STORM MOTIONS MORE PARALLEL TO THE SLOW
MOVING FRONT WILL LEAD TO A FEW REPEATED ROUNDS OF STORMS.
ISOLATED FLASH FLOODING WILL BE POSSIBLE PARTICULARLY ACROSS THE
TENNESSEE VALLEY WHERE LOCAL SOIL CONDITIONS ARE MORE SATURATED.
THE BOUNDARY WILL BECOME MORE PROGRESSIVE BY WEDNESDAY AFTERNOON
AND SWEEP EASTWARD ACROSS THE SOUTHEAST AND TO THE EAST COAST INTO
WEDNESDAY EVENING, WITH SOME MORE ISOLATED STORMS POSSIBLE. MOIST
FLOW ALONG A WARM FRONT LIFTING NORTHWARD AHEAD OF THE SYSTEM WILL
ALSO BRING MODERATE RAINFALL TO THE COASTAL NORTHEAST AS WELL AS
THE POTENTIAL FOR SOME ACCUMULATING SNOW FOR HIGHER ELEVATIONS OF
THE INTERIOR NORTHEAST WEDNESDAY AFTERNOON THROUGH THE EARLY
MORNING HOURS THURSDAY. PRECIPITATION SHOULD COME TO AN END FOR
ALL BUT FLORIDA BY THURSDAY AFTERNOON AS THE FRONT PUSHES INTO THE
ATLANTIC.
ELSEWHERE, THUNDERSTORMS REMAIN IN THE FORECAST FOR SOUTH FLORIDA
WEDNESDAY WITH SOME VERY HEAVY DOWNPOURS AND ISOLATED FLOODING
POSSIBLE FOR URBAN AREAS. EXTREME TO CRITICAL FIRE WEATHER
CONDITIONS HAVE ALSO BEEN OUTLINED BY THE STORM PREDICTION CENTER
IN THE LOS ANGELES VICINITY AS GUSTY WINDS AND DRY CONDITIONS
REMAIN IN PLACE. PRECIPITATION CHANCES WILL RETURN TO THE PACIFIC
NORTHWEST BY THURSDAY EVENING AS ANOTHER PACIFIC SYSTEM APPROACHES
THE REGION. MUCH OF THE LOWER 48 WILL CONTINUE TO SEE WELL ABOVE
AVERAGE TEMPERATURES OVER THE NEXT COUPLE OF DAYS, WITH HIGHS
RUNNING 10-20 DEGREES ABOVE AVERAGE FOR THE SOUTHEAST WEDNESDAY
(60S-70S), THE SOUTH-CENTRAL U.S. THURSDAY (60S-70S), AND THE WEST
THROUGH THURSDAY (40S-50S INTERIOR, 60S-70S WEST COAST AND
DESERTS). THE NORTHEAST WILL BE MORE SEASONABLE WITH HIGHS IN THE
MID-30S (INTERIOR) TO LOW 50S (COAST). ONE REGION THAT WILL SEE
MUCH COLDER TEMPERATURES WILL BE THE NORTHERN PLAINS/UPPER
MIDWEST, WHERE HIGHS WILL MAINLY BE IN THE TEENS AND 20S AND GUSTY
WINDS WILL LEAD TO EVEN COLDER WIND CHILLS. THE NORTHERN HIGH
PLAINS WILL SEE SOME RELIEF THURSDAY AS DOWNSLOPING WINDS BRING
WARMER TEMPERATURES.
PUTNAM
GRAPHICS AVAILABLE AT
HTTPS://WWW.WPC.NCEP.NOAA.GOV/BASICWX/BASICWX_NDFD.PHP
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page