Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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000
FXUS61 KPHI 191930
AFDPHI

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
330 PM EDT SAT APR 19 2014

.SYNOPSIS...
LARGE HIGH PRESSURE CENTERED OVER WESTERN QUEBEC THIS AFTERNOON
WILL BUILD SOUTHEASTWARD. THE HIGH SHOULD CONTINUE TO INFLUENCE
OUR REGION INTO MONDAY NIGHT. A COLD FRONT IS FORECAST TO APPROACH
FROM THE WEST AND IT SHOULD PASS THROUGH OUR REGION LATE ON
TUESDAY. HIGH PRESSURE IS EXPECTED TO FOLLOW FOR WEDNESDAY INTO
FRIDAY. LOW PRESSURE AND A COLD FRONT FROM THE WEST ARE
ANTICIPATED TO ARRIVE ON SATURDAY.

&&

.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
THE GFS INITIALIZATION LOOKED BETTER AT 925MB, THE WRF-NMMB
BETTER AT 850MB AND BOTH ABOUT THE SAME AT 500MB OFF THE 12Z
SOUNDINGS. BUT ONCE AGAIN THROUGH THE SHORT TERM MODEL DIFFERENCES
ARE NOT LARGE ENOUGH TO GIVE CONFLICTING GUIDANCE.

A QUIET NIGHT TONIGHT WITH MAYBE SOME CIRRUS DURING THE EVENING,
OTHERWISE CLEAR SKIES. BIGGEST FORECAST PROBLEM ARE MINIMUM
TEMPERATURES AS WE HAVE CONFLICTING FORCES. AS THE NIGHT
PROGRESSES, THE WINDS ABOVE THE BOUNDARY LAYER ARE FORECAST TO
INCREASE. THE PREDICTED SPEEDS ARE CLOSE TO THE 50/50 THRESHOLD OF
SURFACE MIXING. OUR CONCLUSION WAS TO GIVE THE GRADIENT SOME DUE
EAST OF I95 WHERE OUR MINS ARE PREDICTED TO OCCUR EARLIER AND THEN
OVERALL HIGHER THAN STAT GUIDANCE. NW OF I95 AND THE FALL LINE THE
RADIATIONAL COOLING INVERSION MIGHT BE TOO MUCH TO OVERCOME AND WE
WENT CLOSER TO STAT GUIDANCE. DEW POINTS ARE SO LOW ITS GOING TO
BE TOUGH FOR FROST TO OCCUR ANYWHERE. THE MORE LIKELY PLACES ARE
LOCALES WHERE THE GROWING SEASON HAS NOT BEEN DECLARED STARTED, SO
NO MENTION IN THE GRIDS/ZONES OR HEADLINES.

&&

.SHORT TERM /6 AM SUNDAY MORNING THROUGH 6 PM SUNDAY/...
A SUNNY DAY IS IN STORE AS HIGH PRESSURE BUILDS INTO NEW ENGLAND.
THE ASSOCIATED AIR MASS IS OH SO DRY (NO SC OVER THE OCEAN YET)
THAT THE ONSHORE FLOW SHOULD NOT PRODUCE LITTLE IF ANY CLOUDINESS.
THE ONSHORE FLOW SHOULD KEEP LOCATIONS NEAR THE COAST AND WEST OF
DELAWARE BAY COOLER THAN TODAY. THE LATE APRIL SUN THOUGH FINDS A
WAY TO OUTPERFORM, ESPECIALLY WITH THE TREES WELL BEHIND SCHEDULE.
WE WENT AT OR ABOVE STAT GUIDANCE FROM AROUND I95 AND DE STATE 1
WESTWARD AND NORTHWESTWARD. WE WENT CLOSER TO STAT GUIDANCE EAST
OF THESE ROADWAYS. EVEN WITHOUT THE ONSHORE FLOW, THE ANTECEDENT
AIR MASS IS PREDICTED TO BE RELATIVELY MILDER IN THE NWRN PART OF
OUR CWA. WE ARE GOING TO BE SWITCHING THE STRONGER WINDS ON SUNDAY
VS TODAY AS THE WINDIEST LOCATIONS WILL BE IN EASTERN NJ AND
DELAWARE WITH ABOUT THE SAME OR LESS WIND SPEEDS (DIRECTION EAST
VS NORTH) IN PLACES FARTHER TO THE WEST.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
A RIDGE OF HIGH PRESSURE IS FORECAST TO REMAIN OVER OUR REGION
FOR SUNDAY NIGHT INTO MONDAY NIGHT AS LOW PRESSURE OFF THE
SOUTHEAST COAST MOVES FARTHER OUT TO SEA. A MAINLY CLEAR SKY IS
ANTICIPATED FOR SUNDAY NIGHT AND MONDAY WITH PERHAPS AN INCREASE
IN HIGH CLOUDS FROM THE WEST ON MONDAY NIGHT.

TEMPERATURES ARE EXPECTED TO DROP INTO THE LOWER AND MIDDLE 30S
ACROSS OUR NORTHERN COUNTIES LATE ON SUNDAY NIGHT WHERE WE ARE NOT
YET ISSUING FROST AND FREEZE PRODUCTS. MINIMUM TEMPERATURES IN OUR
CENTRAL AND SOUTHERN COUNTIES SHOULD BE MAINLY IN THE 35 TO 40
DEGREE RANGE. SPOTTY FROST IS POSSIBLE BUT IT DOES NOT SEEM AS
THOUGH IT WILL BE WIDESPREAD ENOUGH TO WARRANT A MENTION AT THIS
POINT. READINGS SHOULD RECOVER NICELY ON MONDAY WITH PLENTY OF
SUNSHINE. HIGHS ON MONDAY AFTERNOON ARE FORECAST TO BE WELL INTO
THE 60S AT MOST LOCATIONS.

THE AXIS OF A MID LEVEL TROUGH IS EXPECTED TO PASS OVERHEAD ON
WEDNESDAY MORNING. A SURFACE COLD ASSOCIATED WITH THE FEATURE
SHOULD MOVE THROUGH OUR REGION LATE ON TUESDAY. WE HAVE MAINTAINED
THE MENTION OF SHOWERS, MAINLY FOR TUESDAY AFTERNOON AND TUESDAY
EVENING. PRECIPITATION TOTALS WILL LIKELY BE LESS THAN A QUARTER
INCH IN OUR FORECAST AREA.

THE MID LEVEL PATTERN SHOULD REMAIN PROGRESS WITH A RIDGE AXIS
PASSING OVERHEAD ON FRIDAY. SURFACE HIGH PRESSURE FROM THE WEST IS
ANTICIPATED TO MOVE ACROSS OUR REGION DURING THE SECOND HALF OF
THE WORK WEEK BRINGING DRY WEATHER AND SEASONABLE TEMPERATURES.

SURFACE LOW PRESSURE IS FORECAST TO PASS ACROSS THE GREAT LAKES
ON FRIDAY AND FRIDAY NIGHT AND INTO THE NORTHEAST ON SATURDAY. AS
A RESULT, WE WILL CARRY A CHANCE OF SHOWERS FOR FRIDAY NIGHT AND
SATURDAY.

&&

.AVIATION /20Z SATURDAY THROUGH THURSDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.

THE 18Z TAFS CONTINUED VFR CONDITIONS.

FOR THE REST THIS AFTERNOON JUST SOME CIRRUS CLOUDS WITH NORTH
WINDS WILL AVERAGE 10 TO 15 KNOTS (PLEASE LOOK AT KACY AND KMIV
NEXT PARAGRAPH). ANY GUSTINESS SHOULD BE 20 KNOTS OR LESS.

FOR KACY AND KMIV AND AIRPORTS IN DELAWARE AND SE NJ, A SEA AND
BAY BREEZE FRONT HAS FORMED. IT JUST WENT THROUGH KACY AND IS
NEARING KMJX. IT WILL CONTINUE TO PROGRESS WWD TO APPROXIMATELY A
KBLM-KNEL- HAMMONTON IN ATLC COUNTY-WESTERN CUMBERLAND NJ AND THRU
KENT AND SUSSEX CTY DELAWARE LATE THIS AFTN AND EARLY THIS EVENING
BEFORE DISSIPATING. WE HAVE AN EAST WIND SHIFT TIME MENTIONED AT
THOSE TERMINALS.

TONIGHT NORTHEAST WINDS ABOUT 5 TO 10 KNOTS UNDER CLEAR SKIES
(MAYBE SOME CIRRUS) AND NO VSBY RESTRICTIONS.

ON SUNDAY CLEAR SKIES CONTINUING. WINDS WILL BE EAST AVERAGING
AROUND 10 KNOTS WITH GUSTINESS TO AROUND 20 KTS AT KMIV AND KACY
AS WELL AS OTHER NEAR THE COAST AIRPORTS. THERE IS A POCKET OF
STRONGER WINDS PASSING ALOFT ON SUNDAY MORNING. A BRIEF ONE OR TWO
HOUR PERIOD OF GUSTINESS IS POSSIBLE AT THE KPHL AREA AIRPORTS.

OUTLOOK...
SUNDAY NIGHT THROUGH MONDAY NIGHT...MAINLY VFR.

TUESDAY AND TUESDAY NIGHT...MAINLY VFR WITH A CHANCE OF AFTERNOON
AND EVENING SHOWERS.

WEDNESDAY THROUGH THURSDAY...MAINLY VFR.

&&

.MARINE...
THE SMALL CRAFT ADVISORY CONTINUES FOR THE OCEAN WATERS THROUGH
THE DAY ON SUNDAY. SEAS AT BUOY 9 ARE STILL AT 5 FEET, SO AT LEAST
FOR THE SOUTHERN WATERS, THE GAP OF NON-SMALL CRAFT ADVISORY WINDS
IS GETTING SMALLER ALL THE TIME. THE GUIDANCE HAS BEEN TOO LOW
WITH SWELLS LATELY.

WE ARE GOING TO BE ADDING DELAWARE BAY TO THE SMALL CRAFT
ADVISORY FOR SUNDAY DAY. WE HAVE HIGHER CONFIDENCE ABOUT THE WIND
CRITERIA BEING MET IN THE LOWER BAY THAN THE UPPER BAY.
REGARDLESS, WINDS SHOULD START DIMINISHING DURING SUNDAY AFTERNOON
AND MIGHT FALL BELOW SMALL CRAFT ADVISORY CRITERIA ALONG THE
MONMOUTH COUNTY ATLANTIC WATERS AND ALL OF DELAWARE BAY BY THE END
OF THE DAY. SEAS ON THE OCEAN WILL TAKE LONGER TO SUBSIDE BELOW
SMALL CRAFT ADVISORY CRITERIA.

OUTLOOK...
SUNDAY NIGHT...A SMALL CRAFT ADVISORY IS IN EFFECT FOR OUR OCEAN
WATERS FROM MANASQUAN INLET SOUTHWARD MAINLY FOR SEAS IN THE
PERSISTENT NORTHEAST FLOW.

MONDAY...WAVE HEIGHTS MAY REMAIN NEAR 5 FEET INTO MONDAY ON OUR
OCEAN WATERS MAINLY FROM ATLANTIC CITY SOUTHWARD.

MONDAY NIGHT THROUGH WEDNESDAY...NO MARINE HEADLINES ARE
ANTICIPATED.

WEDNESDAY NIGHT...NORTHWESTERLY WIND GUSTS AROUND 25 KNOTS ARE
POSSIBLE.

THURSDAY...NO MARINE HEADLINES ARE ANTICIPATED.

&&

.FIRE WEATHER...
WE ARE GOING TO FLIP OUR FIRE WEATHER CONCERN ON SUNDAY TO THE NJ
PINE BARRENS AS THEY WILL COME CLOSEST TO THE CONFLUENCE OF STRONG
WIND GUSTS, LOW AFTERNOON RELATIVE HUMIDITY LEVELS AND CONTINUED
DRY AND DRYING FINE FUELS. CLOSER TO THE IMMEDIATE COAST, THE
RELATIVE HUMIDITY LEVELS SHOULD NOT BE REACHED. ELSEWHERE, WIND
GUSTS OVERALL ARE EXPECTED TO REMAIN BELOW 20 MPH ON SUNDAY
AFTERNOON.

ON MONDAY WINDS ARE EXPECTED TO BE LIGHTER IN ALL AREAS AND
RELATIVE HUMIDITY LEVELS MIGHT NOT DROP BELOW 30 PERCENT,

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 AM EDT MONDAY FOR ANZ451>455.
     SMALL CRAFT ADVISORY UNTIL 6 PM EDT SUNDAY FOR ANZ450.
     SMALL CRAFT ADVISORY FROM 6 AM TO 6 PM EDT SUNDAY FOR ANZ430-
     431.

&&

$$

SYNOPSIS...IOVINO
NEAR TERM...GIGI
SHORT TERM...GIGI
LONG TERM...IOVINO
AVIATION...GIGI/IOVINO
MARINE...GIGI/IOVINO
FIRE WEATHER...GIGI





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