780
FXUS62 KRAH 030500
AFDRAH
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RALEIGH NC
100 AM EDT FRI OCT 3 2025
SYNOPSIS
CANADIAN HIGH PRESSURE WILL BUILD ACROSS THE EASTERN US, THEN
OFFSHORE, THROUGH THE WEEKEND.
NEAR TERM /THROUGH TONIGHT/
AS OF 210 PM THURSDAY...
A MID/UPR-LEVEL RIDGE, AND ACCOMPANYING MID-LEVEL HIGH/ANTICYCLONE
CENTERED IN 12Z-OBSERVED UPR AIR DATA OVER THE OH VALLEY, WILL
PROGRESS SLOWLY EWD AND ACROSS THE SRN MIDDLE ATLANTIC TONIGHT.
ASSOCIATED DEEP DRYNESS, CHARACTERIZED BY PWS OF GENERALLY 0.5" TO
0.8" AND 50-60% OF NORMAL, WILL REMAIN IN PLACE OVER CNTL NC.
AT THE SURFACE, 1033 MB CANADIAN HIGH PRESSURE CENTERED THIS
AFTERNOON OVER THE NORTHEAST WILL BECOME CENTERED OVER THE MIDDLE
ATLANTIC TONIGHT, WHILE CONTINUING TO RIDGE SWWD ACROSS THE
CAROLINAS AND SOUTHEAST. INITIALLY BREEZY AND OCCASIONALLY GUSTY
NELY SURFACE WINDS THIS AFTERNOON OVER CNTL NC WILL LESSEN AFTER
SUNSET, THEN PROBABLY FULLY DECOUPLE/CALM IN ALL BUT THE COASTAL
PLAIN AND URBAN PIEDMONT OVERNIGHT.
MAINLY CLEAR AND MOSTLY CALM WILL FAVOR STRONG RADIATIONAL COOLING
AND SEASONABLY COOL LOW TEMPERATURES IN THE MID 40S TO LWR 50S,
SUPPORTED BY STATISTICAL (MOS) GUIDANCE THAT TYPICALLY OUTPERFORMS
ALL OTHER IN SUCH REGIMES.
SHORT TERM /FRIDAY AND FRIDAY NIGHT/
AS OF 310 PM THURSDAY...
SOME DEGREE OF A REX BLOCKING PATTERN WILL EVOLVE OVER PARTS OF THE
ERN US INTO THE WEEKEND, AS A MID/UPR-LEVEL TROUGH NOW DIGGING
ACROSS THE MID MS VALLEY SETTLES ACROSS THE LWR MS VALLEY AND CNTL
GULF COAST, EQUATORWARD/BENEATH A PERSISTENT RIDGE OVER THE OH
VALLEY AND MIDDLE ATLANTIC.
AT THE SURFACE, THE CENTER OF CANADIAN HIGH PRESSURE WILL MIGRATE
DOWN THE MIDDLE ATLANTIC COAST AND MAINTAIN SEASONABLY MILD/COOL
NELY FLOW OVER CNTL NC.
WHILE DEEP DRYNESS, CHARACTERIZED BY PWS OF GENERALLY 50-70% OF
NORMAL, WILL REMAIN, STRATOCUMULUS MOISTURE IN NELY AROUND THE RIDGE
AND BENEATH A COUPLE OF LOW-LEVEL TEMPERATURE INVERSIONS, WILL TOO -
SUPPORTIVE OF SCATTERED TO AREAS OF BROKEN, DIURNAL STRATOCUMULUS.
SKIES SHOULD OTHERWISE BE MOSTLY CLEAR. WITH LITTLE TO NO CHANGE IN
AIRMASS OR PROXIMITY OF THE CANADIAN HIGH, TEMPERATURES SHOULD BE
NEAR TO SLIGHTLY ABOVE PERSISTENCE ONES: HIGHS IN THE 70S AND LOWS
IN THE MID-UPR 40S TO LWR-MID 50S, WITH THE LATTER AGAIN SUPPORTED
BY STATISTICAL (MOS) GUIDANCE THAT IS FAVORED IN SUCH REGIMES.
LONG TERM /SATURDAY THROUGH THURSDAY/
AS OF 148 PM THURSDAY...
AN ANOMALOUS MID-LEVEL RIDGE WILL RE-AMPLIFY OVER EASTERN CANADA
SATURDAY BEFORE SHIFTING OVER THE NORTHEAST US SUNDAY INTO MONDAY.
AN UPPER TROUGH WILL THEN MOVE ACROSS THE GREAT LAKES/OHIO
VALLEY/NORTHEAST US TUESDAY INTO THURSDAY.
AT THE SFC, HIGH PRESSURE WILL REMAIN CENTERED JUST OFF THE DELMARVA
PENINSULA SATURDAY, SHIFTING A BIT FURTHER OFFSHORE THROUGH SUNDAY.
WHILE FLOW SATURDAY WILL BE WEAK, IT WILL REMAIN A BIT MORE ENELY IN
NATURE. THIS SHOULD KEEP DAYTIME HIGHS A FEW DEGREES COOLER (UPPER
70S TO AROUND 80) THAN SUNDAY WHEN FLOW TURNS MORE ESELY AND HIGHS
REACH THE LOWER 80S. DEEPER, ANOMALOUS MOISTURE SHOULD STAY SOUTH
AND WEST OF OUR AREA PROMOTING A DRY WEEKEND. OVERNIGHT LOWS IN THE
MID/UPPER 50S TO LOWER 60S ARE EXPECTED EACH NIGHT.
PERSISTENT ESELY FLOW EARLY NEXT WEEK SHOULD ENHANCE MOISTURE FLUX
ACROSS OUR AREA. MID-LEVEL VORTICITY ASSOCIATED WITH REMNANTS OF AN
UPPER WAVE OVER THE DEEP SOUTH MAY PROMOTE SCATTERED SHOWERS MONDAY
AND TUESDAY (ESPECIALLY OVER THE NC/SC BORDER; WESTERN AND SOUTHERN
PIEDMONT). OVERALL THOUGH, QPF SHOULD BE LIMITED EARLY NEXT WEEK.
BEYOND TUESDAY, DETERMINISTIC AND ENSEMBLE GUIDANCE IS SURPRISINGLY
IN GOOD AGREEMENT WRT TO THE TIMING OF THE AFOREMENTIONED UPPER
TROUGH AND THE EASTWARD PROGRESSION OF AN ASSOCIATED COLD FRONT. IN
GENERAL, A BETTER CHANCE FOR WIDESPREAD PRE-FRONTAL RAIN LOOKS
PROMISING LATER WEDNESDAY THROUGH MID-THURSDAY. IT'S A BIT TOO FAR
TO GET INTO DETAILS, BUT IT IS WORTH NOTING THAT GUIDANCE CURRENTLY
MAXIMIZES MID/UPPER FORCING WELL TO OUR NORTH. AS SUCH, HIGHER QPF
MAY TREND NORTH OF US AS WELL. ALTHOUGH, SOME INSTABILITY MAY BE
POSSIBLE WEDNESDAY AFTERNOON AND EVENING WHICH COULD ENHANCE RAIN
RATES IN ISOLATED CELLS. WE'LL CONTINUE TO MONITOR AS WE GET CLOSER
TO MIDDLE OF NEXT WEEK.
OTHERWISE, EXPECT HIGHS IN THE MID/UPPER 70S TO LOWER 80S DURING
THIS PERIOD. ENSEMBLES/DETERMINISTIC GUIDANCE IS ALSO IN PRETTY GOOD
AGREEMENT PUSHING THE POST-FRONTAL COOLER AIRMASS INTO OUR AREA BY
NEXT THURSDAY. AS SUCH, OUR CURRENT FORECAST SUGGESTS HIGHS IN THE
UPPER 60S/LOWER 70S (OVERNIGHT LOWS IN THE UPPER 40S/LOWER 50S) AS
POSSIBLE ON DAY 8.
AVIATION /06Z FRIDAY THROUGH TUESDAY/
AS OF 100 AM FRIDAY...
CANADIAN HIGH PRESSURE ENTRENCHED OVER THE REGION WILL SUPPORT
PREVAILING VFR CONDITIONS THROUGH THE 24 HR TAF PERIOD. WINDS WILL
REMAIN FROM THE NE, WITH A BRIEF PERIOD OF POST-SUNRISE GUSTINESS
EXPECTED AT KFAY.
OUTLOOK: WHILE PERSISTENT HIGH PRESSURE OVER THE MIDDLE ATLANTIC
WILL FAVOR PRIMARILY VFR CONDITIONS, ASSOCIATED NELY TO ELY FLOW
AROUND IT WILL FAVOR BOTH PERIODS OF STRATOCUMULUS BASED AROUND AND
JUST ABOVE MVFR RANGE AND ALSO A RISK OF PATCHY FOG, AS LOW-LEVEL
MOISTURE GRADUALLY INCREASES THROUGH THE WEEKEND. THE CHANCE OF
SHOWERS WILL ALSO GRADUALLY INCREASE EARLY TO ESPECIALLY MID-NEXT
WEEK, AHEAD OF AN APPROACHING COLD FRONT.
RAH WATCHES/WARNINGS/ADVISORIES
NONE.
SYNOPSIS...MWS
NEAR TERM...MWS
SHORT TERM...MWS
LONG TERM...LUCHETTI
AVIATION...CBL/MWS
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page