419
FXUS61 KLWX 020047
AFDLWX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
847 PM EDT FRI AUG 1 2025
SYNOPSIS
A STRONG AREA OF HIGH PRESSURE OVER THE NORTHEAST CONUS
THROUGH THIS WEEKEND WILL GRADUALLY SHIFT OFFSHORE EARLY NEXT
WEEK. HIGH PRESSURE WEAKENS INTO NEXT WEEK WHILE THE NEXT
FRONT IS EXPECTED TO SLOWLY APPROACH FROM THE SOUTH.
NEAR TERM /THROUGH SATURDAY/
EVENING UPDATE: NO SIGNIFICANT CHANGES HAVE BEEN MADE TO THE
PREVIOUS FORECAST. PREVIOUS DISCUSSION FOLLOWS...
STRONG 1030 MB HIGH PRESSURE CENTER OVER NORTHWEST WISCONSIN WILL
GRADUALLY BUILD EASTWARD OVER THE WEEKEND BRINGING A SIGNIFICANT
CHANGE IN AIR MASS WITH TEMPERATURES MORE TYPICAL OF SEPTEMBER. FOR
TODAY, A LOW CLOUD OVERCAST IS EXPECTED TO PERSIST NORTH OF A
FRONTAL ZONE LOCATED SOUTH OF THE AREA WITH ISOLATED TO SCATTERED
SHOWERS ARE EXPECTED AS AN UPPER TROUGH SWINGS ACROSS THE NORTHEAST
AND MID-ATLANTIC STATES. IT WILL BE REFRESHINGLY MUCH COOLER WITH
HIGHS IN THE MID 70S UNDER A NOTICEABLE NORTHERLY BREEZE.
CLEARING WILL OCCUR FROM NORTH TO SOUTH THIS EVENING AS HIGH
PRESSURE CONTINUES TO BUILD FROM THE WEST AND PUSHES DRIER AIR INTO
THE REGION. OVERNIGHT LOWS WILL GENERALLY BE IN THE MID TO UPPER
50S TO THE WEST OF THE BLUE RIDGE, AND 60S FURTHER EAST.
SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/
HIGH PRESSURE WILL SET UP OVER THE NORTHEAST CONUS THROUGHOUT THE
WEEKEND. THIS WILL RESULT IN SLIGHTLY BELOW NORMAL TEMPERATURES AND
A MUCH LESS HUMID AIR MASS. EXPECT HIGHS IN THE LOW TO MID 80S, WITH
SUNDAY BEING THE WARMER OF THE TWO, ALONG WITH DEW POINTS IN THE
UPPER 50S TO LOW 60S. OVERNIGHT LOWS WILL ALSO BE SLIGHTLY BELOW
AVERAGE, DROPPING INTO THE 50S TO LOW 60S (CLOSER TO MID 60S IN THE
METROS).
LONG TERM /MONDAY THROUGH FRIDAY/
1022-1024MB HIGH PRESSURE WILL REMAIN WEDGED DOWN THE EASTERN SIDE
OF THE APPALACHIANS FROM NORTH-CENTRAL PA THROUGH MONDAY. MEANWHILE,
QUASI-ZONAL FLOW WILL CONTINUE ALOFT LEADING TO A CONTINUATION
SEASONABLY COOL TEMPERATURES, LOW HUMIDITY, AND DRY CONDITIONS AT
LEAST FOR EARLY AUGUST STANDARDS. HIGHS MONDAY WILL PUSH INTO THE
MID TO UPPER 80S EAST OF THE ALLEGHENIES WITH MID TO UPPER 70S AND
LOW 80S ACROSS THE SHENANDOAH VALLEY/BLUE RIDGE/CATOCTINS/HIGHER
ELEVATIONS ABOVE 2000 FEET. DEWPOINTS WILL RISE SLIGHTLY INTO THE
UPPER 50S AND LOW 60S AS THE WEDGE OF HIGH PRESSURE WEAKENS WHILE
SHIFTING EAST INTO WESTERN NEW YORK AND CENTRAL NEW ENGLAND. LOWS
MONDAY NIGHT WILL FALL BACK INTO THE LOW TO MID 60S EAST OF THE BLUE
RIDGE (BALTIMORE/WASHINGTON DC METROS UPPER 60S) WITH MID TO UPPER
50S OVER THE MOUNTAINS.
WEDGING HIGH PRESSURE OVER THE INTERIOR NORTHEAST AND NORTHERN MID-
ATLANTIC WILL CONTINUE TO WEAKEN TUESDAY WHILE SHIFTING OFFSHORE
TUESDAY INTO MIDWEEK. MEANWHILE, A POTENT UPPER LEVEL TROUGH WILL
DIG ACROSS THE GREAT LAKES AND THROUGH THE SOUTHEASTERN U.S CONUS
SENDING GULF MOISTURE NORTHWARD INTO THE REGION MIDWEEK. SHOWERS AND
T-STORM CHANCES WILL INCREASE AS A RESULT OF THIS MOISTURE BEING
FUNNELED NORTHWARD BETWEEN THE WESTERN ATLANTIC RIDGE AND INCOMING
SHORTWAVE TROUGH. HIGHEST CHANCES FOR STORMS TUESDAY AND WEDNESDAY
WILL BE DURING THE DIURNAL HEATING PERIOD OVER THE MOUNTAINS. THIS
IS DUE IN PART TO THE SLOW EROSION OF THE WEDGE/RESIDUAL DRY AIR AS
HIGH PRESSURE KICKS OFFSHORE. THE WEDGE OF HIGH PRESSURE WILL
FINALLY ERODE OUT THURSDAY AS THE TROUGH SWINGS THROUGH THE REGION.
IN ADDITION TO THE TROUGH, WILL BE AN AREA OF LOW PRESSURE OFF THE
CAROLINAS. THIS MAY FURTHER INHIBIT THE INFLUX OF MOISTURE FROM GULF
AS WELL AS ATLANTIC LATER THIS WEEK. WITH THAT SAID, HAVE KEPT
SLIGHTLY HIGHER SHOWER AND THUNDERSTORM CHANCES IN THURSDAY AND
FRIDAY AS LOW AND MID-LEVL MOISTURE INCREASES ACROSS THE REGION. NO
REAL SIGNIFICANT FRONTAL BOUNDARIES LOOK TO CROSS THE AREA DURING
THIS TIME TO FLIP OVER THE AIRMASS INTO THE UPCOMING WEEKEND AHEAD.
TEMPERATURES WILL REMAIN AT OR JUST BELOW AVERAGE THROUGH AT LEAST
THURSDAY. HIGHS EACH DAY WILL PUSH INTO THE UPPER 70S TO MID 80S
WITH OVERNIGHT LOWS IN THE UPPER 50S AND LOW TO MID 60S.
AVIATION /01Z SATURDAY THROUGH WEDNESDAY/
CLEARING IS EXPECTED FROM NORTH TO SOUTH LATER THIS EVENING AS
DRIER AIR FILTERS IN BEHIND THE COLD FRONT. SCATTERED TO BROKEN
DECKS OF STRATOCUMULUS CLOUDS ARE EXPECTED DURING THE DAY BOTH
SATURDAY AND SUNDAY WITH CLEARING EXPECTED DURING THE OVERNIGHT
HOURS.
PREDOMINANTLY VFR CONDITIONS ARE EXPECTED MONDAY THROUGH THURSDAY.
SOME TEMPORARY REDUCTIONS ARE POSSIBLE TUESDAY THROUGH THURSDAY
AFTERNOONS ESPECIALLY OVER THE MOUNTAIN TERMINALS WHERE SHOWERS AND
THUNDERSTORMS LOOK TO OCCUR. WINDS WILL REMAIN OUT OF THE EAST AND
NORTHEAST MONDAY AND TUESDAY AT LESS THAN 10 KTS. WINDS CHANGE BACK
TO THE WEST AND SOUTHWEST BY THE MIDDLE OF NEXT WEEK.
MARINE
NORTHERLY WINDS WILL START TO DIMINISH LATE TONIGHT INTO
SATURDAY. SMALL CRAFT ADVISORIES WILL GRADUALLY DROP OFF THROUGH
THE DAY ON SATURDAY AS THIS OCCURS, WITH SUB-SCA CONDITIONS
EXPECTED THEREAFTER.
NO MARINE HAZARDS ARE EXPECTED MONDAY AND TUESDAY AS HIGH PRESSURE
SITS NEARBY. SUB-SCA LEVEL WINDS ARE EXPECTED OUT OF THE EAST AND
NORTHEAST AT LESS THAN 15 KTS. WINDS TURN BACK TO THE WEST AND
SOUTHWEST WEDNESDAY AND THURSDAY AS HIGH PRESSURE PUSHES
OFFSHORE.
TIDES/COASTAL FLOODING
WINDS TURN ONSHORE OVER THE WEEKEND AS HIGH PRESSURE SETS UP OVER
THE NORTHEAST CONUS. THIS WIND DIRECTION WILL RESULT IN INCREASED
TIDAL ANOMALIES THROUGH SUNDAY, WHICH COULD PUSH THE SENSITIVE TIDAL
SITES INTO MINOR FLOOD STAGE, PARTICULARLY AT ANNAPOLIS. THIS WATER
WILL THEN ALSO MAKE A RUN UP THE TIDAL POTOMAC SUNDAY INTO MONDAY,
WHICH COULD BRING THOSE SITES CLOSE TO MINOR BY LATE SUNDAY INTO
MONDAY.
LWX WATCHES/WARNINGS/ADVISORIES
DC...NONE.
MD...NONE.
VA...NONE.
WV...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL NOON EDT SATURDAY FOR ANZ532-533-
540>542.
SMALL CRAFT ADVISORY UNTIL MIDNIGHT EDT SATURDAY NIGHT FOR
ANZ534-537-543.
SYNOPSIS...CJL
NEAR TERM...CJL/KJP
SHORT TERM...CJL
LONG TERM...EST
AVIATION...CJL/EST
MARINE...CJL/EST
TIDES/COASTAL FLOODING...CJL
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