Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1145 PM EDT MON APR 20 2015

.SYNOPSIS...
A WARM FRONT JUST NORTHWEST OF INTERSTATE 95 WILL MERGE WITH AN
EASTWARD MOVING COLD FRONT AND PUSH OUT TO SEA BY MORNING. SEVERAL
REINFORCING COLD FRONTS WILL MOVE SOUTHEAST THROUGH THE MID ATLANTIC
STATES TUESDAY, WEDNESDAY AND THURSDAY AFTERNOONS. LOW PRESSURE
WILL CROSS TO THE SOUTH OF THE AREA SATURDAY INTO SATURDAY NIGHT.
HIGH PRESSURE WILL GRADUALLY BUILD IN FROM THE WEST THROUGH THE
WEEKEND.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
WE WILL CANCEL BOTH WATCHES AS THEY WERE SET TO EXPIRE AT MIDNIGHT
AND THUNDERSTORM ACTIVITY HAS WEAKENED IN THE MORE STABLE AIR
OVER OUR CWA. THE FRONT IS STILL WEST OF US, SO SOME ACTIVITY 
WILL CONTINUE INTO THE OVERNIGHT.

THE HIGH TIDE CYCLE HAS PASSED, SO WE WILL CANCEL THE COASTAL
FLOOD ADVISORY. WE ISSUED AN SPS FOR THE NORTHERN CWA FOG.

AFTER WHATEVER GUSTY WSHIFT LATE THIS EVENING, THEN THE WIND
BRIEFLY BACKS TO SW AHEAD OF THE PRIMARY CFP AND THERE MAY BE
ANOTHER SHOWER OR TSTM AROUND 06Z THEN VARIABLE CLOUDS AND A
STEADY WEST WIND TOWARD DAWN.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
DEEP LOW PRESSURE REMAIN ACROSS CANADA WHILE HIGH PRESSURE BUILDS
OVER THE SE STATES. RATHER STRONG PRESSURE GRADIENT WILL CREATE
MODERATE/GUSTY WINDS TUESDAY. MOSTLY FAIR WEATHER IS EXPECTED.
TEMPERATURES WILL BE SEASONABLY COOL WITH HIGHS IN THE LOW/MID 60S
MOST AREAS. WEST WINDS 15 MPH WITH GUSTS 25-30 MPH.

&&

.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
A PERSISTENT UPPER LEVEL TROUGH WILL SPIN OVER THE GREAT LAKES AREA 
WITH A GRADUAL PUSH TO EAST THROUGH THE WEEK, SETTLING OVER EXTREME 
NORTHEASTERN UNITED STATES AND SPINNING ACROSS EASTERN CANADA 
THROUGH THE WEEKEND. SEVERAL SHORTWAVES EMBEDDED IN THE UPPER LEVEL 
FLOW WILL ROTATE THROUGH OUR AREA AND WE WILL SEE SHOWERS CROSS 
PARTS OF THE REGION THROUGH THE WEEK. 

A COLD FRONT WILL PUSH DOWN THROUGH THE REGION WEDNESDAY INTO 
WEDNESDAY NIGHT, WITH A CHANCE FOR SOME SHOWERS ACROSS THE AREA. 
COLDER AIR LOCATED ALONG AND BEHIND THE FRONT MAY ALLOW FOR SOME 
SNOW FLAKES TO FALL ACROSS THE HIGHER TERRAIN OF THE SOUTHERN 
POCONOS. 

A SECOND COLD FRONT IS FORECAST TO ARRIVE BY THURSDAY EVENING BUT IT 
APPEARS TO LACK MUCH MOISTURE. THEREFORE, ONLY A FEW LIGHT SHOWERS 
ACROSS THE NORTHWESTERN AREAS MAY OCCUR AS THE MOISTURE LESSENS AS 
IT PUSHES THROUGH THE REGION. 

THE UPPER LOW FINALLY MOVES EASTWARD BUT THE CYCLONIC FLOW WILL 
REMAIN ACROSS THE REGION INTO THE WEEKEND WITH A CHANCE FOR SHOWERS 
CONTINUING. 

THE MODELS ARE SHOWING THAT A LOW PRESSURE SYSTEM WILL CROSS TO THE 
SOUTH OF THE REGION DURING THE WEEKEND. JUST HOW FAR NORTH THE 
SYSTEM GETS WILL DICTATE WHETHER OR NOT WE SEE SHOWERS PUSH 
NORTHWARD INTO OUR SOUTHERN AREAS. WE HAVE INCLUDED JUST A SLIGHT 
CHANCE FOR SOME SHOWERS FOR SATURDAY AND SATURDAY NIGHT ACROSS THE 
SOUTHERN PORTION OF THE FORECAST AREA. 

HIGH PRESSURE WILL THEN BUILD IN FROM THE WEST FOR SUNDAY AND MONDAY 
WITH A DRY PERIOD EXPECTED ACROSS OUR REGION.

&&

.AVIATION /04Z TUESDAY THROUGH SATURDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, 
KMIV, KACY, AND SURROUNDING AREAS.

THROUGH TONIGHT...00Z/21 TAFS POSTED WITH SOME UNCERTAIN TIMING
OF POTENTIALLY STRONGER TSTMS AND GUSTY WINDS PER HRRR. FIRST
STORM VCNTY KRDG HAD A WEST GUST 38 KT AT 2227Z.

IFR CIGS NW OF THE QSTRY FRONT, ESPECIALLY KABE. ELSEWHERE, VFR
CIGS WITH A PERIOD OF IFR CONDS IN SHOWERS AND TSTMS TONIGHT.
LIGHT WINDS, MOSTLY NE-SE NW OF THE QSTRY FNT AND SOUTHERLY
GUSTING TO 15 KT SOUTH OF THE FRONT. ALL WINDS TURNING WNW
OVERNIGHT POST LATE NIGHT CFP.  

TUESDAY...VFR SCT-BKN AOA 4500 FT WITH GUSTY W WINDS 20-25 KT.

OUTLOOK...

TUESDAY NIGHT...MAINLY VFR CONDITIONS EXPECTED.

WEDNESDAY...MAINLY VFR CONDITIONS EXPECTED WITH SUB-VFR SHOWERS 
POSSIBLE AS A COLD FRONT CROSSES THE REGION. 

THURSDAY THROUGH SATURDAY...MAINLY VFR CONDITIONS EXPECTED.

&&

.MARINE...
SCA CONDITIONS WILL CONTINUE ACROSS THE OCEAN AREAS THE REST OF
TONIGHT INTO TUESDAY. SCA FOR SEAS INTO TONIGHT AND THEN WINDS
AND SEAS TUE. SCT TSTMS TONIGHT AND THEN FAIR WEATHER TUE. AREAS
OF FOG INTO TONIGHT.

SUB-SCA CONDITIONS ACROSS DEL BAY ATTM WITH PROBABLE HIGHER WAVES 
ACROSS THE MOUTH OF THE BAY AND POSSIBLY SOME HIGHER SEAS UP ACROSS 
THE SRN PART OF THE BAY. WE WILL KEEP THE SCA FLAG FOR AWHILE INTO 
THE EVENING BUT DROP IT ACROSS NRN DEL BAY. IT MAY NEED TO BE ISSUED 
THERE AGAIN FOR WINDS G25 FOR TUESDAY. SCT TSTMS TONIGHT BUT FAIR 
WEATHER FOR TUE. 

OUTLOOK... 
WEDNESDAY...SEAS WILL INCREASE AND NEAR 5 FEET DURING THE
AFTERNOON BUT SHOULD SUBSIDE FAIRLY QUICKLY. WINDS WILL GUST
AROUND 20 KNOTS. A SMALL CRAFT ADVISORY MAY BE NEEDED FOR A TIME
ON WEDNESDAY.

THURSDAY...SUB- ADVISORY CONDITIONS ARE EXPECTED ON THE AREA
WATERS.

FRIDAY...WINDS WILL BE GUSTY OUT OF THE NORTHWEST AND A SMALL
CRAFT ADVISORY MAY BE NEEDED.

SATURDAY...SUB- ADVISORY CONDITIONS ARE EXPECTED ON THE AREA
WATERS.

&&

.CLIMATE...
THREE RER RAINFALL REPORTS SO FAR TODAY (PHL, ILG, GED) AND THESE
MAY BE UPDATED AT 2 AM AFTER THE CLIMATE DAY ENDS AT 1 AM.

ILG CLIMATE HAD TO HAVE SOME ESTIMATED INFORMATION DUE TO SOME
MISSING DATA (LOW TEMP, RH'S) BUT WE THINK THE DATA IS VERY CLOSE
TO REALITY.

&&
 
.EQUIPMENT...
NWR PHL PROBLEMS RESOLVED.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...NONE.
NJ...NONE.
DE...NONE.
MD...NONE.
MARINE...SMALL CRAFT ADVISORY UNTIL 6 PM EDT TUESDAY FOR ANZ431-450>455.

&&

$$
SYNOPSIS...MEOLA
NEAR TERM...DRAG/GIGI/O'HARA
SHORT TERM...O'HARA
LONG TERM...MEOLA
AVIATION...DRAG/MEOLA/O'HARA
MARINE...DRAG/MEOLA/O'HARA
CLIMATE...
EQUIPMENT...

National Weather Service Glossary of Abbreviations