800
FXUS61 KLWX 171530
AFDLWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
1030 AM EST MON FEB 17 2025
SYNOPSIS
AN EXPANSIVE ARCTIC HIGH PRESSURE WILL BUILD INTO THE NORTH-
CENTRAL U.S. THIS WEEK. MEANWHILE, AN AREA OF LOW PRESSURE WILL
TAKE SHAPE OVER THE MISSISSIPPI RIVER VALLEY BY MID WEEK, THEN
TRACK TO THE CAROLINAS AND OFF THE EAST COAST WEDNESDAY INTO
THURSDAY. HIGH PRESSURE WILL TAKE OVER LATE IN THE WEEK.
NEAR TERM /THROUGH TUESDAY/
WINDS REMAIN ELEVATED WITH GUSTS OF 40 TO 55 MPH OVER THE
HIGHER ELEVATIONS AND NEAR/NORTH OF I-66/US-50. THIS IS WHERE
WIND ADVISORIES REMAIN IN EFFECT UNTIL MIDDAY. A FEW AREAS MAY
NEED AN EXTENSION TO THE ADVISORY, BUT IN GENERAL, FORECAST
SOUNDINGS SHOW LESS WIND AVAILABLE IN THE BOUNDARY LAYER TO MIX
DOWN BY THIS AFTERNOON (30 TO 40 MPH GUSTS LIKELY REMAIN
COMMON).
WEST OF THE ALLEGHENY FRONT, SNOW SHOWERS WILL GRADUALLY
DIMINISH THROUGH EARLY AFTERNOON, BUT BLOWING AND DRIFTING SNOW
WILL REMAIN AN ISSUE THROUGH THE DAY.
COLD WEATHER IS EXPECTED TONIGHT, AND WITH LOWS DROPPING INTO
THE SINGLE DIGITS AND BLUSTERY CONDITIONS CONTINUING, AREAS
ALONG AND WEST OF THE ALLEGHENY FRONT WILL SEE WIND CHILLS
AROUND 10 TO 15 DEGREES BELOW ZERO. FURTHER EAST, WIND CHILLS
WILL BE IN THE TEENS AND SINGLE DIGITS ABOVE ZERO.
A SURFACE RIDGE EXTENDING FROM A LARGE ARCTIC HIGH OVER THE
NORTHERN PLAINS WILL EXPAND INTO THE MID-ATLANTIC TUESDAY. WINDS
WILL CONTINUE TO GRADUALLY DIMINISH, WITH DAYTIME GUSTS OF 20
TO 30 MPH POSSIBLE EAST OF THE MOUNTAINS.
SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/
LOW PRESSURE WILL TAKE SHAPE OVER THE MID SOUTH TUESDAY NIGHT
INTO WEDNESDAY. THE LATEST TREND IN GUIDANCE CONTINUES TO SHOW
MORE SEPARATION BETWEEN A SOUTHERN STREAM WAVE AND A NORTHERN
STREAM UPPER LOW WITH LESS PHASING. HAVE TRENDED THE FORECAST IN
THIS DIRECTION WITH GENERALLY THE I-64 CORRIDOR TO SOUTHERN MD
AND SOUTH SEEING THE BEST CHANCE FOR SEVERAL INCHES OF SNOW FROM
THE SOUTHERN STREAM WAVE AS IT PASSES OFF THE CAROLINAS. FURTHER
NORTH, SNOW STILL APPEARS PLAUSIBLE AT SOME POINT AS THE
NORTHERN STREAM UPPER LOW PIVOTS OVERHEAD LATE WEDNESDAY INTO
THURSDAY. OVERALL, PROBABILITIES HAVE TRENDED DOWN FOR
SIGNIFICANT SNOW ESPECIALLY NORTH OF I-66 AND WEST OF I-95 FOR
THIS SYSTEM. THAT'S NOT TO SAY THAT IMPACTFUL SNOW (I.E. BURSTS
OF SNOW SHOWERS IN A COLD ENVIRONMENT) WON'T OCCUR, BUT THE
CHANCES OF WARNING LEVEL SNOW HAVE GREATLY DIMINISHED FURTHER
NORTH AND WEST. WILL CONTINUE TO MONITOR THE DEEP NORTHERN
STREAM UPPER LOW - IF IT CAN MAINTAIN ENOUGH DEPTH AND ATTAIN A
NEGATIVE TILT BEFORE THE SOUTHERN STREAM WAVE IS TOO FAR
OFFSHORE, SNOW COULD DEVELOP ALONG AN INVERTED TROUGH.
LONG TERM /FRIDAY THROUGH SUNDAY/
A COUPLE OF LINGERING UPSLOPE SNOW SHOWERS IN THE APPALACHIANS
THURSDAY EVENING WILL FADE AWAY LATER THURSDAY NIGHT INTO EARLY
FRIDAY. HIGH PRESSURE WILL BUILD IN FROM THE WEST FRIDAY THROUGH
SATURDAY. DRY AND CHILLY CONDITIONS EXPECTED THROUGH THIS PERIOD.
HIGHS FRIDAY AND SATURDAY WILL BE ABOUT 10 DEGREES BELOW AVERAGE
WITH HIGHS IN THE MIDDLE TO UPPER 30S. LOWS WILL ALSO BE ABOUT 10 TO
MAYBE 15 DEGREES BELOW AVERAGE BOTTOMING OUT IN THE LOWER 20S.
THE HIGH PRESSURE CENTER WILL MOVE TO THE EAST COAST TO ALLOW FOR A
MODIFYING SOUTHERLY WIND TO DEVELOP SATURDAY NIGHT AND PERSIST
THROUGH THE DAY ON SUNDAY. TEMPERATURES WILL STILL BE ON THE CHILLY
SIDE WITH HIGHS MAKING THEIR WAY TO NEAR 40 DEGREES WITH COLDER
READINGS IN THE WEST SATURDAY AND SUNDAY.
THERE ARE LARGE MODEL DISAGREEMENTS FOR SUNDAY AS TO IF OR WHEN THE
NEXT LOW PRESSURE SYSTEM DEVELOPS AND ATTEMPTS TO AFFECT THE REGION
WITH WINTRY WEATHER. THE GFS SHOWS A DEVELOPING LOW PRESSURE SYSTEM
OVER THE SOUTHEAST U.S. MOVING INTO OUR REGION FROM THE SOUTHWEST
AND BRINGING A WINTRY MIX TO OUR WESTERN HALF OF OUR REGION AND RAIN
TO OUR EASTERN HALF LATE SUNDAY INTO MONDAY. THE EUROPEAN MODEL
BARELY SHOWS ANY LOW PRESSURE SYSTEM NEAR US AT ALL SUNDAY INTO
MONDAY WITH MAYBE A HINT OF ONE MOVING OUT TO SEA NEAR THE NORTH AND
SOUTH CAROLINA COASTS. THE CANADIAN MODEL SHOWS A LOW PRESSURE
SYSTEM MOVING ACROSS THE SOUTHEAST U.S., THEN OUT TO SEA AS IT
INTENSIFIES PIVOTING NORTH TOWARD NEW ENGLAND. THERE IS PLENTY OF
TIME TO DETERMINE WHICH MODEL LEANS CORRECT, BUT KNOW THAT WE
SHOULD STILL SEE BELOW NORMAL TEMPERATURES DURING THE PERIOD OF
THIS POSSIBLE LOW PRESSURE SYSTEM AND THAT WINTER IS NOT OVER.
IN TERMS OF TIMING, IT CURRENTLY LOOKS LIKE THE BULK OF THE
SNOW THAT DOES FALL WILL OCCUR WEDNESDAY AFTERNOON THROUGH
WEDNESDAY NIGHT, WITH SOME LOW END POTENTIAL FOR SOME LIGHTER
SNOW LINGERING INTO THURSDAY MORNING. MODELS ARE IN GOOD
AGREEMENT THAT COLDER AIR WILL FILTER INTO THE AREA IN
NORTHWESTERLY FLOW BEHIND THE DEPARTING SYSTEM. HIGH
TEMPERATURES WILL STRUGGLE TO REACH FREEZING ON THURSDAY, AND
THEN DROP BACK INTO THE SINGLE DIGITS AND TEENS THURSDAY NIGHT.
WINDS CHILLS ARE EXPECTED TO BOTTOM OUT IN THE SINGLE DIGITS
ABOVE/BELOW ZERO LATE THURSDAY NIGHT. DRY CONDITIONS AND
CONTINUED BELOW AVERAGE TEMPERATURES ARE EXPECTED FOR FRIDAY AND
SATURDAY. HIGH TEMPERATURES ARE FORECAST TO BE IN THE 30S FOR
MOST (20S MOUNTAINS), WITH LOWS IN THE TEENS TO NEAR 20.
AVIATION /16Z MONDAY THROUGH FRIDAY/
WHILE WIND GUSTS HAVE DROPPED SOME SINCE YESTERDAY EVENING,
GUSTS DO PERSIST IN THE 30 TO 45 KNOT RANGE. POST-FRONTAL WAVE
CLOUDS CONTINUE BUT ARE BECOMING MORE SCATTERED. BY THIS
AFTERNOON, SUSTAINED WINDS SHOULD DROP CLOSER TO 15-20 KT WITH
GUSTS TO 35 KT, BEFORE DIMINISHING FURTHER AFTER SUNSET.
VFR CONDITIONS WILL CONTINUE THROUGH TUESDAY, WITH 20 KT GUSTS
RETURNING DURING THE DAYLIGHT HOURS.
SUB-VFR CONDITIONS APPEAR LESS LIKELY FOR NORTHERN TERMINALS
ALONG WITH LOWER SNOW POTENTIAL WEDNESDAY AFTERNOON INTO
THURSDAY. IMPROVEMENT BACK TO VFR CONDITIONS IS EXPECTED BY
THURSDAY AFTERNOON. WINDS ARE FORECAST TO BE OUT OF THE NORTH ON
WEDNESDAY, AND THEN NORTHWEST ON THURSDAY INTO FRIDAY.
MARINE
A LARGE AREA OF HIGH PRESSURE WILL DESCEND INTO THE NORTH-
CENTRAL U.S. SINCE THE HIGH WON'T BE DIRECTLY OVERHEAD, WINDS
WILL ONLY GRADUALLY DIMINISH THROUGH TUESDAY. GALE WARNINGS
CONTINUE THROUGH THIS AFTERNOON. SMALL CRAFT ADVISORIES MAY BE
NEEDED FOR PORTIONS OF THE WATERS THROUGH TUESDAY NIGHT.
LOW PRESSURE PASSING TO THE SOUTH MAY BRING SNOW, ESPECIALLY IN
THE VICINITY OF SOUTHERN MARYLAND LATE WEDNESDAY INTO THURSDAY.
NORTHERLY WINDS ARE EXPECTED ON WEDNESDAY. WINDS WILL SHIFT TO
NORTHWESTERLY LATE WEDNESDAY NIGHT INTO THURSDAY. SCA GUSTS
APPEAR LIKELY DURING THAT TIME. WINDS DIMINISH FRIDAY.
LWX WATCHES/WARNINGS/ADVISORIES
DC...WIND ADVISORY UNTIL NOON EST TODAY FOR DCZ001.
MD...GALE WARNING UNTIL 4 PM EST THIS AFTERNOON FOR MDZ008.
WIND ADVISORY UNTIL NOON EST TODAY FOR MDZ003>006-008-011-013-
014-501>508.
BLIZZARD WARNING UNTIL 3 PM EST THIS AFTERNOON FOR MDZ001.
COLD WEATHER ADVISORY FROM 10 PM THIS EVENING TO 10 AM EST
TUESDAY FOR MDZ001.
WINTER WEATHER ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR
MDZ501.
VA...WIND ADVISORY UNTIL NOON EST TODAY FOR VAZ025>031-040-053-054-
501-503>508-526.
WINTER WEATHER ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR
VAZ503.
WV...WIND ADVISORY UNTIL NOON EST TODAY FOR WVZ050>053-055-502>504-
506.
BLIZZARD WARNING UNTIL 3 PM EST THIS AFTERNOON FOR WVZ501-505.
COLD WEATHER ADVISORY FROM 10 PM THIS EVENING TO 10 AM EST
TUESDAY FOR WVZ501-505.
WINTER WEATHER ADVISORY UNTIL 3 PM EST THIS AFTERNOON FOR
WVZ503.
MARINE...GALE WARNING UNTIL 4 PM EST THIS AFTERNOON FOR ANZ530>543.
WIND ADVISORY UNTIL NOON EST TODAY FOR ANZ530.
SYNOPSIS...ADS/DHOF
NEAR TERM...ADS/DHOF
SHORT TERM...DHOF
LONG TERM...KLW
AVIATION...ADS/KLW/DHOF
MARINE...ADS/KLW/DHOF
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page