724
FXUS01 KWBC 210801
PMDSPD
SHORT RANGE FORECAST DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
300 AM EST TUE NOV 21 2023
VALID 12Z TUE NOV 21 2023 - 12Z THU NOV 23 2023
...ACTIVE WEATHER EXPECTED TO IMPACT PRE-THANKSGIVING TRAVELS FOR
MUCH OF THE U.S. EAST OF THE MISSISSIPPI RIVER BUT SHOULD EXIT THE
EAST COAST JUST IN TIME FOR THANKSGIVING...
...SEVERE WEATHER THREAT WILL PROGRESS FROM WEST TO EAST ACROSS
THE CENTRAL GULF GULF STATES INTO THE SOUTHEAST...
...HEAVY RAIN EXPECTED TO MOVE THROUGH THE INTERIOR MID-ATLANTIC
TONIGHT WITH SOME SNOW AND FREEZING RAIN OVER INTERIOR NEW ENGLAND
INTO WEDNESDAY...
...SNOW IS FORECAST TO DEVELOP OVER THE NORTHERN ROCKIES TO
NORTHERN HIGH PLAINS TO BEGIN THANKSGIVING HOLIDAY...
A DEVELOPING LOW PRESSURE SYSTEM ROUGHLY CENTERED OVER THE
MISSISSIPPI VALLEY EARLY THIS MORNING WILL CONTINUE TO BRING AN
EXPANDING AREA OF INCLEMENT WEATHER THROUGH MUCH OF THE EASTERN
HALF OF THE COUNTRY AS WE HEAD TOWARD THE PEAK OF THE
PRE-THANKSGIVING DAY TRAVEL PERIOD. PRECIPITATION ASSOCIATED WITH
THIS SYSTEM IS ALREADY RATHER EXPANSIVE EARLY THIS MORNING,
STRETCHING FROM THE CENTRAL GULF COAST UP THROUGH THE TENNESSEE
AND OHIO VALLEYS, INTO THE MIDWEST AND THE SOUTHERN PART OF THE
GREAT LAKES. THUNDERSTORMS ARE EXPECTED TO BE MOST INTENSE EARLY
TODAY ACROSS THE LOWER MISSISSIPPI VALLEY WITH SEVERE WEATHER
EXCEPTED BEFORE COOLER AND DRIER AIR ARRIVES BEHIND A DYNAMIC COLD
FRONT. FARTHER NORTH, RAIN HEAVY AT TIMES, WITH EMBEDDED
THUNDERSTORMS, IS FORECAST TO QUICKLY OVERSPREAD THE APPALACHIANS
AND THE INTERIOR MID-ATLANTIC BY THIS EVENING, WITH RAINFALL
TOTALS LOCALLY A FEW INCHES POSSIBLE. NEARLY ALL OF THESE REGIONS
HAVE HAD MUCH BELOW AVERAGE PRECIPITATION OVER THE PAST SEVERAL
WEEKS, WITH AREAS FROM THE LOWER MISSISSIPPI VALLEY INTO THE
TENNESSEE VALLEY IN SEVERE TO EXCEPTIONAL DROUGHT CONDITIONS.
GIVEN THESE RECENT DRY CONDITIONS, STREAM FLOWS AND SOIL MOISTURE
ARE BELOW AVERAGE, WHICH SHOULD DECREASE THE THREAT OF FLASH
FLOODS. HOWEVER, ISOLATED FLASH FLOODING STILL POSSIBLE GIVEN THE
HEAVY RAINFALL THREAT, ESPECIALLY ACROSS URBAN AREAS.
STILL FARTHER NORTH ACROSS NEW ENGLAND, TRAPPED COLD AIR WILL
SUPPORT SNOW AND AREAS OF FREEZING RAIN BEGINNING TUESDAY EVENING
OVER UPSTATE NEW YORK AS THE MOISTURE FROM THE LOW PRESSURE SYSTEM
ARRIVES FROM THE SOUTHWEST. A FEW INCHES OF SNOW IS POSSIBLE
ACROSS INTERIOR NEW ENGLAND BEFORE TAPERING OFF FROM WEST TO EAST
LATER ON WEDNESDAY. BY THE MORNING ON THANKSGIVING DAY, MUCH OF
THE EASTERN SEABOARD SHOULD CLEAR OUT JUST IN TIME FOR HOLIDAY
FESTIVITIES AS THE STORM SHOULD BEGIN TO MOVE OUT TO SEA.
HOWEVER, MUCH OF THE NORTHEAST WILL LIKELY CONTEND WITH BLUSTERY
CONDITIONS AS THE STORM IS FORECAST TO DEEPEN QUITE RAPIDLY JUST
OFFSHORE.
MUCH MORE TRANQUIL WEATHER IS EXPECTED ACROSS MOST REGIONS TO THE
WEST OF THE MISSISSIPPI RIVER TO THE WEST COAST OVER THE NEXT FEW
DAYS. MUCH OF THIS REGION WILL BE DRY, SAVE FOR THE PACIFIC
NORTHWEST WHERE A SLOW MOVING FRONT WILL BRING LIGHT TO MODERATE
PRECIPITATION AMOUNTS BY TONIGHT INTO EARLY WEDNESDAY. A LARGE
DOME OF HIGH PRESSURE WILL PROMOTE VERY GUSTY SANTA ANA WINDS OVER
SOUTHERN CALIFORNIA TODAY GIVEN A TIGHT PRESSURE GRADIENT IN
PLACE. BY WEDNESDAY NIGHT INTO THURSDAY MORNING, THE MOISTURE IN
THE PACIFIC NORTHWEST IS FORECAST TO JOIN FORCE WITH COLDER AIR
ARRIVING FROM WESTERN CANADA TO DEVELOP AN EXPANDING AREA OF SNOW
TO ENSHROUD THE NORTHERN ROCKIES INTO THE NORTHERN HIGH PLAINS TO
BEGIN THANKSGIVING DAY.
ABOVE AVERAGE TEMPERATURES ARE EXPECTED THE NEXT COUPLE OF DAYS
FROM THE WEST COAST, ACROSS THE ROCKIES AND INTO THE NORTHERN TO
CENTRAL PLAINS. MUCH COLDER TEMPERATURES EXPECTED ACROSS THE
NORTHERN PLAINS BEGINNING LATE WEDNESDAY INTO THANKSGIVING AS A
STRONG COLD FRONT PUSHES SOUTHWARD OUT OF CENTRAL CANADA.
KONG/ORAVEC
GRAPHICS AVAILABLE AT
HTTPS://WWW.WPC.NCEP.NOAA.GOV/BASICWX/BASICWX_NDFD.PHP
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page