905
FXUS61 KPHI 090531
AFDPHI
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
131 AM EDT MON MAR 9 2026
WHAT HAS CHANGED
DENSE FOG ADVISORIES ISSUED/EXTENDED FOR LAND AND MARINE ZONES
IN AND ADJACENT TO SOUTHERN NEW JERSEY AND THE DELMARVA.
KEY MESSAGES
1. DENSE FOG WILL ENVELOP MOST OF SOUTHERN NEW JERSEY AND THE
DELMARVA EARLY THIS MORNING, BURNING OFF AFTER SUNRISE.
2. WARMER AIR WILL CONTINUE TO OVERSPREAD THE REGION THROUGH
MID WEEK BEFORE A STRONG COLD FRONT BRINGS MORE SEASONABLE
CONDITIONS BACK FOR THE LATE WEEK.
DISCUSSION
KEY MESSAGE 1...DENSE FOG WILL ENVELOP MOST OF SOUTHERN NEW
JERSEY AND THE DELMARVA EARLY THIS MORNING, BURNING OFF AFTER
SUNRISE.
RADIATIONAL COOLING HAS COME ON STRONG NOW THAT THE FRONT HAS
DEPARTED AND CLOUDS ARE CLEARING, A FRONT WHICH HASN'T
ESPECIALLY EFFECTIVELY CLEANSED MOISTURE FROM THE LOWER
ATMOSPHERE. THIS MAY HAPPEN DURING THE DAY MONDAY AS STRONG
SOLAR RADIATION HELPS MIX DOWN DRIER AIR FROM ALOFT, BUT AT
LEAST FOR NOW, THIS ISN'T GOING TO BE A SOLUTION. INSTEAD, WE
HAVE INCREASINGLY WIDESPREAD DENSE FOG DEVELOPING, ESPECIALLY
NEAR THE COAST AND OVER THE STILL CHILLY WATERS. THIS LIKELY
CONTINUES SLOWLY EXPANDING THRU THE REST OF TONIGHT BEFORE
BURNING OFF AFTER SUNRISE AS THE STRENGTHENING MARCH SUN ANGLE
STARTS DOING ITS DIRTY WORK, BUT UNTIL THEN, HAVE ISSUED DENSE
FOG ADVISORIES THRU MID- MORNING. AFTER THE FOG BURNS OFF,
PLENTY OF SUNSHINE WILL PUSH TEMPS BACK WELL INTO THE 60S TO
NEAR 70 ONCE AGAIN.
KEY MESSAGE 2...WARMER AIR WILL CONTINUE TO OVERSPREAD THE REGION
THROUGH MID WEEK BEFORE A STRONG COLD FRONT BRINGS MORE SEASONABLE
CONDITIONS BACK FOR THE LATE WEEK.
THE REGION WILL BE BENEATH A FAIRLY BENIGN UPPER PATTERN THROUGH
TUESDAY NIGHT. AT THE SURFACE, HIGH PRESSURE CENTERED OVER PORTIONS
OF THE SOUTHEAST AND MID-ATLANTIC WILL GRADUALLY SHIFT EASTWARD
THROUGH TUESDAY NIGHT. THIS WILL SET THE STAGE FOR LIGHT SOUTHERLY
FLOW TO CONTINUE ACROSS THE AREA, AND A CONTINUED WARMING TREND
IS EXPECTED TO CONTINUE THROUGH WEDNESDAY. DAYTIME HIGHS TUESDAY
AND WEDNESDAY ARE EXPECTED TO BE IN THE LOW TO MID 70S FOR MOST
OF THE AREA WITH MORNING LOWS IN THE 40S AND 50S. HIGHS WILL BE
COOLER IN PROXIMITY TO THE OCEAN DUE TO POTENTIAL SEA BREEZE
DEVELOPMENT BOTH TUESDAY AND WEDNESDAY. IN ADDITION, THERE IS
THE POTENTIAL FOR FOG DEVELOPMENT MONDAY NIGHT AND TUESDAY
NIGHT. RELATIVELY LIGHT WINDS IN COMBINATION WITH WARM AND MOIST
AIR OVERSPREADING THE REGION WITH VERY COOL OCEAN TEMPERATURES
COULD LEAD TO AREAS OF DENSE FOG, PARTICULARLY NEAR THE COASTS.
BEGINNING ON WEDNESDAY, THE UPPER PATTERN WILL BECOME MUCH MORE
UNSETTLED AS A POTENT TROUGH OVER CENTRAL PORTIONS OF THE US
BEGINS TO WORK EASTWARD TOWARDS OUR AREA. BROAD ASCENT IS LIKELY
TO BEGIN OVERSPREADING THE REGION DURING THIS TIME, AND WILL
LEAD TO A CHANCE FOR SCATTERED SHOWERS WITHIN THE WARM AIR
ADVECTION REGIME. ON WEDNESDAY, SHOWER ACTIVITY APPEARS MOST
LIKELY ALONG AND NORTH OF I- 95, WITH POPS CURRENTLY IN THE
30-50% RANGE, WITH POPS AROUND 20% SOUTH OF IT. RAINFALL ON
WEDNESDAY IS NOT EXPECTED TO BE WIDESPREAD AND AMOUNTS WILL BE
LIGHT.
WEDNESDAY NIGHT INTO THURSDAY MORNING, HEIGHT FALLS ASSOCIATED
WITH THE APPROACHING TROUGH ARE EXPECTED TO MAXIMIZE, WITH THE
TROUGH AXIS IS EXPECTED TO SHIFT EASTWARD ACROSS THE REGION BY
THURSDAY AFTERNOON. A SURFACE LOW IS EXPECTED TO PASS TO THE
NORTH OF THE REGION WITH A TRAILING COLD FRONT MOVING THROUGH
THE AREA THURSDAY MORNING. ALONG AND AHEAD OF THE COLD FRONT
WEDNESDAY NIGHT INTO THURSDAY, POPS INCREASE TO 50-70% AREAWIDE.
MOST GUIDANCE FEATURES A LINE OF SHOWERS MOVING THROUGH THE
REGION. VERY STRONG WIND FIELDS ALOFT AND AT LEAST MODEST
INSTABILITY ARE FORECAST TO BE PRESENT, SO THUNDERSTORMS WILL BE
POSSIBLE. WHILE THE TIMING OF THIS ACTIVITY IS NOT EXPECTED TO
BE IDEAL FOR STRONG TO SEVERE STORMS, GUSTY WINDS CANNOT BE
RULED OUT AS THIS ACTIVITY MOVES THROUGH. AFTER THE FRONTAL
PASSAGE, SOME LINGERING RAIN OR SNOW SHOWERS WILL BE POSSIBLE
ACROSS THE AREA THROUGH THURSDAY AFTERNOON AS COLDER AIR FILTERS
INTO THE REGION.
MORE SEASONABLE TEMPERATURES ARE EXPECTED THROUGH THE WEEKEND
IN THE WAKE OF THE COLD FRONT. A COUPLE OF WEAK DISTURBANCES MAY
GLANCE THE AREA, WITH THE FIRST BEING FRIDAY AFTERNOON INTO
FRIDAY NIGHT AND THE SECOND BEING SATURDAY NIGHT INTO SUNDAY.
THIS COULD LEAD TO SOME LIGHT RAIN OR SNOW ACROSS PORTIONS OF
THE AREA, BUT IT STILL APPEARS THAT THESE DISTURBANCES MAY TRACK
FAR ENOUGH TO THE NORTH TO BRING LITTLE OR NO IMPACTS. WILL
CONTINUE TO FEATURE 20-30% POPS DURING THIS TIME PERIOD, WITH
THE HIGHER CHANCES BEING ACROSS NORTHERN PORTIONS OF THE AREA.
AVIATION /06Z MONDAY THROUGH FRIDAY/
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
THRU 12Z THIS MORNING...VFR INLAND TERMINALS FROM I-95 N AND W,
BUT IFR/LIFR/VLIFR FOR MIV/ACY WITH DENSE FOG AT TIMES. THIS MAY
CREEP TOWARDS THE I-95 TERMINALS TOO, BUT NOT CERTAIN ON THIS.
LIGHT/VARIABLE WINDS. LOW CONFIDENCE.
TODAY...VFR AFTER FOG BREAKS MID-MORNING. WINDS FROM THE SSW
AROUND 5 TO 10 KTS. MAYBE A FEW GUSTS 15-20 KTS IN THE
AFTERNOON. MODERATE CONFIDENCE.
TONIGHT...VFR TO START, THEN LOW CLOUDS/FOG MAY START CREEPING
INLAND FROM THE COAST, WITH MIV/ACY AGAIN MOST AT RISK. WINDS
BECOMING LIGHT/VARIABLE. LOW CONFIDENCE.
OUTLOOK...
TUESDAY THROUGH TUESDAY NIGHT...PRIMARILY VFR. PERIODS OF SUB-
VFR CONDITIONS WILL BE POSSIBLE IN FOG AND PERHAPS LOW CLOUDS
AT NIGHT/EARLY MORNING HOURS, THOUGH HOW FAR INLAND SUB-VFR
CONDITIONS ARE ABLE TO MAKE IT REMAINS IN QUESTION.
WEDNESDAY THROUGH WEDNESDAY NIGHT...SUB-VFR CONDITIONS POSSIBLE
IN RAIN SHOWERS.
THURSDAY...SUB-VFR CONDITIONS EXPECTED IN WIDESPREAD SHOWERS.
SOME THUNDER IS POSSIBLE. CONDITIONS WILL LIKELY IMPROVE THROUGH
THE DAY THOUGH LINGERING RAIN OR SNOW SHOWERS WILL BE POSSIBLE.
GUSTY WINDS EXPECTED.
THURSDAY NIGHT...VFR.
FRIDAY...PRIMARILY VFR. SOME LIGHT RAIN OR SNOW IS POSSIBLE FOR
THE LEHIGH VALLEY TERMINALS.
MARINE
MARINE DENSE FOG ADVISORIES EXTENDED/EXPANDED TO ALL WATERS THRU
6 PM THIS EVENING, AND MAY NEED FURTHER EXTENSION THROUGH
TONIGHT. WINDS AND SEAS WILL REMAIN SUB-SCA THRU TONIGHT.
OUTLOOK...
TUESDAY THROUGH TUESDAY NIGHT...SUB-SCA CONDITIONS EXPECTED
WITH WINDS UNDER 25 KT AND SEAS UNDER 5 FEET. MARINE FOG IS
POSSIBLE, MAINLY AT NIGHT.
WEDNESDAY THROUGH FRIDAY...SCA CONDITIONS EXPECTED. GALES ARE
POSSIBLE ON THURSDAY. SOUTHERLY WINDS 10-20 KT WITH GUSTS TO 25
KT ARE EXPECTED WEDNESDAY, BECOMING SOUTHWESTERLY AND INCREASING
TO 20- 25 KT WITH GUSTS 30-35 KT WEDNESDAY NIGHT INTO THURSDAY,
BEFORE BECOMING WEST-NORTHWESTERLY BEHIND A COLD FRONT THURSDAY
AFTERNOON. THERE MAY BE A LULL IN WINDS BEFORE THEY AGAIN
INCREASE OUT OF THE SOUTH TO 15-20 KT WITH GUSTS TO 30 KT
FRIDAY. SEAS 4-7 FEET ON WEDNESDAY WILL INCREASE TO 6-12 FEET
WEDNESDAY NIGHT INTO THURSDAY, DECREASING BACK TO 4-7 FEET
FRIDAY. SHOWERS AND PERHAPS A FEW THUNDERSTORMS ARE LIKELY
WEDNESDAY NIGHT INTO THURSDAY.
PHI WATCHES/WARNINGS/ADVISORIES
PA...NONE.
NJ...DENSE FOG ADVISORY UNTIL 10 AM EDT THIS MORNING FOR NJZ016>027.
DE...DENSE FOG ADVISORY UNTIL 10 AM EDT THIS MORNING FOR DEZ002>004.
MD...DENSE FOG ADVISORY UNTIL 10 AM EDT THIS MORNING FOR MDZ020.
MARINE...DENSE FOG ADVISORY UNTIL 6 PM EDT THIS EVENING FOR ANZ430-431-
450>455.
DISCUSSION...COOPER/MJL/RCM
AVIATION...COOPER/MJL/RCM
MARINE...COOPER/MJL/RCM
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page