629
FXUS61 KLWX 241857
AFDLWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
257 PM EDT SAT OCT 24 2026
WHAT HAS CHANGED
A FROST ADVISORY HAS BEEN ISSUED FROM 1 AM TO 9 AM SUNDAY FOR
PORTIONS OF NORTHERN VIRGINIA AND CENTRAL AND NORTHERN MARYLAND.
A COASTAL FLOOD ADVISORY MAY BE NEEDED THIS EVENING FOR
ALEXANDRIA. SKY COVER WAS INCREASED A BIT INTO TONIGHT ACROSS
THE SOUTHERN HALF OF THE FORECAST AREA, BUT THE FORECAST
OTHERWISE REMAINS ON TRACK FOR THE COMING WEEK.
KEY MESSAGES
- 1) FROST OR FREEZING TEMPERATURES ARE POSSIBLE IN MANY AREAS
TONIGHT AND SUNDAY NIGHT.
- 2) DRY WEATHER CONTINUES THROUGH NEXT WEEK ALONG WITH
GENERALLY SEASONABLE TEMPERATURES.
DISCUSSION
KEY MESSAGE 1...FROST OR FREEZING TEMPERATURES ARE POSSIBLE IN
MANY AREAS TONIGHT AND SUNDAY NIGHT.
HIGH PRESSURE REMAINS CENTERED TO OUR NORTHEAST THIS AFTERNOON
AND WILL SLOWLY DRIFT SOUTHWESTWARD THROUGH EARLY MONDAY.
FAVORABLE CONDITIONS FOR RADIATIONAL COOLING WILL CONTINUE THE
NEXT TWO NIGHTS, ALBEIT WITH SOME CAVEATS.
THE GROWING SEASON FOR 2026 HAS ENDED ALONG AND WEST OF THE BLUE
RIDGE AND CATOCTIN MOUNTAINS, BUT CONTINUES EAST OF THERE. ANY
HEADLINES FOR FROST/FREEZE CONDITIONS WILL ONLY BE ISSUED WHERE
THE GROWING SEASON REMAINS ACTIVE.
OTHER THAN SOME SUBTLE DIFFERENCES, TONIGHT INTO SUNDAY MORNING
SHOULD REFLECT A LOT OF PERSISTENCE FROM SATURDAY MORNING. THIS
RESULTED IN 31-36 DEGREE LOW TEMPERATURES ACROSS NORTHERN
VIRGINIA AND CENTRAL AND NORTHERN MARYLAND, PARTICULARLY IN
RURAL, LOW-LYING AREAS. THEREFORE, A FROST ADVISORY HAS BEEN
ISSUED FOR THESE AREAS FROM 1 TO 9 AM SUNDAY. FELT THAT
SUBFREEZING TEMPERATURES WOULD BE TOO LOCALIZED FOR A WARNING.
AND WHILE OUTLYING AREAS ALONG AND EAST OF I-95 COULD BE CHILLY
AS WELL, THE FROST POTENTIAL SEEMED TOO ISOLATED FOR AN
ADVISORY AT THIS TIME. MEANWHILE, CONFIDENCE IS LOWER FOR AN
ADVISORY IN CENTRAL VIRGINIA DUE TO HIGHER DEW POINTS AND
POTENTIAL CLOUD COVER, AS THIS AFTERNOON'S STRATOCUMULUS FIELD
CONTINUES TO DRIFT WESTWARD AND POSSIBLY BANK ALONG THE BLUE
RIDGE TONIGHT IF IT DOESN'T BREAK APART.
THE HIGH WILL BE DRIFTING SOUTHWEST TOWARD THE CENTRAL
APPALACHIANS BY MONDAY MORNING, WITH SEVERAL COMPETING FACTORS
INFLUENCING TEMPERATURES. LOW LEVEL FLOW WILL TURN WESTERLY, SO
AREAS ALONG AND EAST OF I-95 MAY HAVE A CHANCE OF BEING COLDER
THAN SUNDAY WITHOUT THE MODIFYING MARINE INFLUENCE. TEMPERATURES
WILL ALSO BE RAPIDLY WARMING ALOFT, SO THE RIDGES AND ANY
LOCATION THAT DOESN'T COMPLETELY DECOUPLE WILL LIKELY BE WARMER.
THERE IS ALSO A SIZABLE RANGE OF DEW POINT TEMPERATURES FORECAST
IN MODELS. HOWEVER, THE GRADIENT WILL BE NEGLIGIBLE WITH
DECOUPLING LIKELY, AND THE NAM HAS BEEN PARTICULARLY CONSISTENT
IN SHOWING SHARP SURFACE INVERSIONS AND THE COLDEST TEMPERATURES
OF THE WEEKEND. ALL THAT TO SAY, WHILE COVERAGE IS A BIT
UNCERTAIN, THE FROST AND FREEZE THREAT WILL PERSIST THROUGH
MONDAY MORNING.
ONLY MINOR CHANGES HAVE BEEN MADE TO THE PREVIOUS MIN
TEMPERATURE FORECASTS, WHICH ARE NEAR OR BELOW THE COLDEST
GUIDANCE WHICH PERFORMS BEST IN RADIATIONAL COOLING (MOS, NBM
10TH PERCENTILE AND CANADIAN REGIONAL).
EXPECT TEMPERATURES TO RISE ABOVE NORMAL (UPPER 60S TO LOWER
70S) BY MONDAY AFTERNOON AS THE WARMING AIRMASS MIXES TO THE
SURFACE. MINIMAL CLOUD COVER AND LIGHT WINDS WILL REMAIN
PERSISTENT.
KEY MESSAGE 2...DRY WEATHER CONTINUES THROUGH NEXT WEEK ALONG
WITH GENERALLY SEASONABLE TEMPERATURES.
DRY WEATHER CONTINUES INTO THE MIDWEEK PERIOD AS SURFACE HIGH
PRESSURE LINGERS TO THE SOUTH TUESDAY AND WEDNESDAY. A BACKDOOR DRY
FRONTAL BOUNDARY ASSOCIATED WITH A LOW OVER THE NORTHERN PLAINS
LIKELY TRAVERSES THROUGH THE REGION DURING THIS TIME, BUT NO
PRECIPITATION IS ANTICIPATED FROM THIS AS MOISTURE/PWATS REMAIN LOW.
AT MOST, CLOUD COVER BEGINS TO INCREASE DURING THIS PERIOD, WITH
DAYTIME TEMPERATURES APPROACHING THE MID-70S AS HIGH PRESSURE
PERSISTS.
LOOKING AHEAD, A WEAK DISTURBANCE OVER THE OHIO RIVER VALLEY
POTENTIALLY MOVES THROUGH THE MID-ATLANTIC LATE IN THE WEEK. IMPACTS
FROM THIS LOOK MINIMAL AT THIS TIME, AS PWATS CONTINUE TO RANGE ON
THE DRY SIDE WHILE WINDS REMAIN LIGHT. OVERALL, NO PRECIPITATION IS
CURRENTLY ANTICIPATED FOR THE ENTIRE 7-DAY FORECAST PERIOD AT THIS
TIME. DRY CONDITIONS CONTINUE TO PREVAIL WITH SEASONABLE
TEMPERATURES RANGING IN THE 60S-70S DURING THE DAY, WITH OVERNIGHT
LOWS MOSTLY IN THE 40S THROUGHOUT THE WEEK.
AVIATION /18Z SATURDAY THROUGH THURSDAY/
VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH EARLY NEXT WEEK.
THERE ARE SOME HINTS THAT A SLIGHT UPTICK IN LOW-LEVEL MOISTURE
COULD LEAD TO SOME PATCHY FOG DURING THE EARLY MORNING HOURS
TONIGHT, AND MAYBE MORE SO SUNDAY NIGHT/MONDAY MORNING, THOUGH
CONFIDENCE IN TIMING AND EXTENT OF FOG IS LOW AT THIS TIME. THE
NAM AND RELATED GUIDANCE IS BY FAR THE MOST AGGRESSIVE WITH
THIS OUTCOME (ESPECIALLY MONDAY MORNING), BUT IS AN OUTLIER.
LIGHT E TO SE WINDS ARE EXPECTED TODAY, WITH LIGHT TO CALM
WINDS TONIGHT. WIND DIRECTION MAY BE A BIT VARIABLE, RANGING
FROM SE TO NE AS HIGH PRESSURE PASSES DIRECTLY OVERHEAD SUNDAY.
WINDS BECOME NORTHWESTERLY MONDAY BUT REMAIN LESS THAN 10 KT.
VFR CONDITIONS ARE EXPECTED TO CONTINUE THROUGH THURSDAY NEXT WEEK.
WINDS SHIFT NORTH TO NORTHWESTERLY TUESDAY IN THE WAKE OF A DRY COLD
FRONT, THEN SHIFT EAST TO SOUTHEASTERLY BETWEEN WEDNESDAY AND
THURSDAY. CLOUD COVER COULD BEGIN TO INCREASE SOMEWHAT BETWEEN
WEDNESDAY/THURSDAY AS A FRONTAL BOUNDARY APPROACHES, BUT NO
PRECIPITATION IS ANTICIPATED AT THIS TIME.
MARINE
HIGH PRESSURE WILL BUILD OVERHEAD THIS WEEKEND. WINDS WILL VARY
A BIT FROM NORTHEAST TO SOUTHEAST, BUT AT LIGHT SPEEDS LESS THAN
10 KNOTS. WINDS STAY BELOW SCA CRITERIA MONDAY WHILE BECOMING
WESTERLY.
A DRY BACKDOOR COLD FRONT PASSING THROUGH COULD BRING WIND GUSTS
NEAR SCA CRITERIA ON TUESDAY BEFORE DIMINISHING AGAIN OVERNIGHT.
NORTHERLY WINDS SHIFT EASTERLY WEDNESDAY IN THE WAKE OF THE
FRONT.
TIDES/COASTAL FLOODING
GENERALLY LIGHT BUT STEADY EAST TO SOUTHEAST WINDS ARE EXPECTED
TO KEEP WATER LEVELS ELEVATED THROUGH SUNDAY. WHEN PAIRED WITH
HIGH ASTRONOMICAL TIDES DUE TO THE UPCOMING FULL MOON ON OCTOBER
26, ADDITIONAL ROUNDS OF MINOR TIDAL FLOODING ARE POSSIBLE.
GIVEN THE STEADY ANOMALIES THIS MORNING, COASTAL FLOOD
ADVISORIES WERE ISSUED FOR ANNE ARUNDEL, CALVERT, CHARLES, AND
KING GEORGE COUNTIES. ALEXANDRIA AND HARFORD/HAVRE DE GRACE MAY
BE CLOSE TO REACHING MINOR FLOOD STAGE THIS EVENING. AFTER THIS
CYCLE, MAINLY ANNAPOLIS HAS A CHANCE OF REACHING MINOR FLOOD
STAGE SUNDAY AFTERNOON. GUIDANCE DOES SHOW A MORE NOTABLE
DECLINE IN WATER LEVELS BY MONDAY WHEN FLOW FINALLY TURNS
WESTERLY.
LWX WATCHES/WARNINGS/ADVISORIES
DC...NONE.
MD...FROST ADVISORY FROM 1 AM TO 9 AM EDT SUNDAY FOR MDZ004>006-008-
503-505-507-508.
COASTAL FLOOD ADVISORY UNTIL 8 PM EDT THIS EVENING FOR MDZ014.
COASTAL FLOOD ADVISORY UNTIL 5 PM EDT THIS AFTERNOON FOR
MDZ016.
COASTAL FLOOD ADVISORY UNTIL 7 PM EDT THIS EVENING FOR MDZ018.
VA...FROST ADVISORY FROM 1 AM TO 9 AM EDT SUNDAY FOR VAZ040-051-501-
502-505-506-526-527.
COASTAL FLOOD ADVISORY UNTIL 5 PM EDT THIS AFTERNOON FOR
VAZ057.
WV...NONE.
MARINE...NONE.
DISCUSSION...ADS/DHOF/SRT
AVIATION...ADS/DHOF/SRT
MARINE...ADS/DHOF/SRT
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page