877
FXUS01 KWBC 231947
PMDSPD
SHORT RANGE FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
346 PM EDT SUN APR 23 2023
VALID 00Z MON APR 24 2023 - 00Z WED APR 26 2023
...MARCH-LIKE TEMPERATURES TO ENGULF MUCH OF THE EASTERN
TWO-THIRDS OF THE LOWER 48, ADDITIONAL FROSTS/FREEZES EXPECTED;
WARMER IN THE SOUTHWEST..
...DAMP AND DREARY CONDITIONS TO LINGER IN NEW ENGLAND
TONIGHT-MONDAY; MORE SHOWERS AND STORMS TO DEVELOP IN THE SOUTH
CENTRAL U.S....
...MOUNTAIN SNOW AND COASTAL/VALLEY SHOWERS REACHING THE PACIFIC
NORTHWEST WILL CONTINUE TO SPREAD INTO THE NORTHERN AND CENTRAL
ROCKIES...
A LARGE DOME OF CANADIAN HIGH PRESSURE HAS TAKEN HOLD OF THE
NATION'S HEARTLAND AND WILL SPREAD EAST INTO THE MID-SOUTH AND
MID-ATLANTIC DURING THE FIRST HALF OF THE WEEK. ACCOMPANYING THIS
LARGE HIGH PRESSURE SYSTEM IS AN EVEN MORE EXTENSIVE AREA OF BELOW
NORMAL TEMPERATURES. MONDAY'S DAILY LOW TEMPERATURES FROM THE
MIDDLE MISSISSIPPI VALLEY ON EAST INTO THE OHIO/TENNESSEE VALLEYS
AND NORTHERN MID-ATLANTIC WILL PLUNGE NEAR OR BELOW FREEZING,
PROMPTING THE ISSUANCE OF FREEZE WARNINGS AND FROST ADVISORIES IN
SOME OF THESE AREAS. A HANDFUL OF DAILY RECORD LOW MINIMUM AND
MAXIMUM TEMPERATURES ARE POSSIBLE AS WELL. TEMPERATURES EAST OF
THE ROCKIES AND INTO THE MID-ATLANTIC ARE LIKELY TO AVERAGE 10-15
DEGREES BELOW NORMAL THROUGH MID-WEEK, MAKING IT FEEL MORE LIKE
MARCH OUTSIDE RATHER THAN LATE APRIL. THE UNUSUALLY CHILLY
TEMPERATURES WILL BE COLD ENOUGH TO WHERE SOME PRECIPITATION IN
THE UPPER GREAT LAKES WILL FALL IN THE FORM SNOW AT TIMES ON
MONDAY, BUT LITTLE IN THE WAY OF ACCUMULATION IS EXPECTED. FARTHER
WEST, AN UPPER LEVEL RIDGE STRENGTHENING OFF THE COAST TOMORROW
AND INTO MID-WEEK WILL FOSTER WARMER THAN NORMAL TEMPERATURES IN
CALIFORNIA AND THE DESERT SOUTHWEST. BY TUESDAY, PORTIONS OF
CALIFORNIA'S GREAT VALLEY WILL RISE WELL INTO THE 80S WITH DESERT
AREAS OF SOUTHERN CALIFORNIA AND ARIZONA ECLIPSING THE 90 DEGREE
MARK.
ONE OF THE REASONS FOR THE COOLER THAN NORMAL TEMPERATURES REGIME
IN THE EASTERN AND CENTRAL U.S. IS A LARGE, SPIRALING UPPER LOW
OVER THE GREAT LAKES AND ONTARIO IS BLOCKED BY A RIDGE OF HIGH
PRESSURE OVER QUEBEC AND THE DAVIS STRAIT. THIS RIDGE IS FORCING A
STORM SYSTEM OFF THE NORTHEAST COAST TO BECOME STATIONARY, MAKING
FOR A DREARY AND UNSETTLED FIRST HALF OF THE WORK-WEEK THROUGHOUT
MUCH OF NEW ENGLAND. THE UPPER LOW WILL ALSO SPARK SCATTERED
SHOWERS AND THUNDERSTORMS IN THE GREAT LAKES ON MONDAY. FARTHER
SOUTH, ROUNDS OF STRONG STORMS ARE RAPIDLY TRACKING SOUTH OF TEXAS
THIS AFTERNOON AND DRIER CONDITIONS RETURN TONIGHT AND INTO
MONDAY. MEANWHILE, A COLD FRONT OVER FLORIDA WILL SPAWN
STRONG-TO-SEVERE THUNDERSTORMS OVER THE SUNSHINE STATE ON MONDAY.
THE STORM PREDICTION CENTER DOES HAVE A MARGINAL RISK FOR SEVERE
WEATHER FROM CAPE CANAVERAL ON SOUTH TO THE MIAMI METRO AREA. BY
TUESDAY MORNING, A POTENT UPPER LOW TRACKING INTO NORTHERN UTAH IS
SET TO BE THE NEXT WEATHER-MAKER IN THE SOUTH CENTRAL U.S. AS
WIDESPREAD SHOWERS AND THUNDERSTORMS FORM ALONG AND NORTH OF A
WARM FRONT POSITIONED OVER NORTHERN TEXAS. THE STORM PREDICTION
CENTER HAS A SLIGHT RISK FOR SEVERE WEATHER IN SOUTHEAST TEXAS,
WHILE THE WEATHER PREDICTION CENTER HAS A SLIGHT RISK FOR
EXCESSIVE RAINFALL IN AND AROUND BOTH THE ARKLATEX AND EASTERN
OKLAHOMA. THE LOWER ELEVATIONS OF THE COLORADO FRONT RANGE AND THE
HIGH PLAINS OF COLORADO COULD ALSO CONTEND WITH EXCESSIVE
RAINFALL, AS HIGHLIGHTED WITH THE ISSUANCE OF A MARGINAL RISK FOR
TUESDAY.
THE AFOREMENTIONED UPPER LOW RESPONSIBLE FOR THE NEXT ROUND OF
SEVERE WEATHER AND HEAVY RAINFALL IN THE SOUTH CENTRAL U.S. ON
TUESDAY WILL ALSO BE THE REASON FOR MORE MOUNTAIN SNOW AND
VALLEY/COASTAL RAIN FROM THE PACIFIC NORTHWEST TONIGHT AND MONDAY
TO THE NORTHERN AND CENTRAL ROCKIES FOR MONDAY AND TUESDAY. AS
MUCH AS 6-12" OF SNOWFALL ARE FORECAST IN THE HIGHEST ELEVATIONS
OF THE CASCADE RANGE AND BOTH THE NORTHERN AND CENTRAL ROCKIES.
THERE ARE WINTER STORM WATCHES UP FOR THE HIGHEST ELEVATIONS OF
SOUTHWEST MONTANA THAT ARE IN EFFECT FROM MONDAY EVENING THROUGH
TUESDAY MORNING. THE COLORADO ROCKIES FEATURE THE BEST ODDS OF
SEEING SNOWFALL TOTALS GREATER THAN 12" THROUGH TUESDAY EVENING
ACCORDING TO WPC SNOWFALL PROBABILITIES (AS HIGH AS 70% IN THE
TALLEST PEAKS). MEANWHILE, PRECIPITATION WILL BE IN THE FORM OF
RAIN ALONG THE PACIFIC NORTHWEST COAST AND IN THE VALLEYS OF THE
INTERMOUNTAIN WEST. IN WAKE OF THIS STORM, THE BUILDING RIDGE OF
HIGH PRESSURE ALONG THE WEST COAST WILL GIVE THE WESTERN THIRD OF
THE U.S. A SHORT-LIVED REPRIEVE FROM THE ACTIVE PATTERN TO START
THE WEEK, AND ALLOW FOR DRIER AND MORE TRANQUIL WEATHER TO TAKE
SHAPE FOR WEDNESDAY.
MULLINAX
GRAPHICS AVAILABLE AT
HTTPS://WWW.WPC.NCEP.NOAA.GOV/BASICWX/BASICWX_NDFD.PHP
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page