Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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000 FXUS61 KPHI 200137 AFDPHI AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 937 PM EDT SAT APR 19 2014 .SYNOPSIS... STRONG HIGH PRESSURE CENTERED NEAR WESTERN QUEBEC WILL BUILD SOUTHEASTWARD TONIGHT AND SUNDAY. THE HIGH SHOULD CONTINUE TO INFLUENCE OUR WEATHER INTO MONDAY NIGHT. A COLD FRONT IS FORECAST TO APPROACH FROM THE WEST AND MOVE THROUGH OUR REGION LATE TUESDAY. HIGH PRESSURE IS THEN 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/... OUR REGION OVERNIGHT REMAINS BETWEEN STRONG HIGH PRESSURE BUILDING ACROSS SOUTHEASTERN CANADA AND LOW PRESSURE OFF THE GEORGIA COAST. THE SURFACE HIGH TO OUR NORTH WILL BE THE MAIN WEATHER FEATURE, HOWEVER THE PRESENT OF A UPPER-LEVEL JET ACROSS NEW ENGLAND CONTINUES TO PULL A DECENT AMOUNT OF HIGH LEVEL CLOUDINESS ACROSS MUCH OF OUR CWA. AS A RESULT, THE SKY COVER WAS INCREASED SOME MORE FROM PREVIOUSLY. THE CLOUDS SHOULD THIN OUT AND GRADUALLY SHIFT TO THE SOUTH AND EAST AS THE UPPER-LEVEL JET DEPARTS THE NEW ENGLAND AREA OVERNIGHT. OTHERWISE, AS THE NIGHT PROGRESSES THE WINDS ABOVE THE BOUNDARY LAYER ARE FORECAST TO INCREASE. PRIOR TO THIS, MANY AREAS ARE DECOUPLING HOWEVER THERE ARE STILL HIGH CLOUDS ABOVE. CLOSER TO THE COAST, THE WINDS SHOULD INCREASE SOME LATE AS THE PRESSURE GRADIENT STARTS TO TIGHTEN ALLOWING THE ONSHORE FLOW TO RESPOND. DEW POINTS ARE RATHER LOW ACROSS THE NORTHERN AND WESTERN AREAS, THEREFORE ITS GOING TO BE TOUGH FOR FROST TO OCCUR FOR MOST PLACES. AN EARLIER SEA BREEZE FRONT THOUGH THAT MOVED FAIRLY FAR INLAND BEFORE DISSIPATING INCREASED THE SURFACE DEW POINTS IN ITS WAKE. THIS WILL ALL IMPACT THE LOW TEMPERATURES. WHILE A TOUCH OF FROST CANNOT BE RULED OUT, IT APPEARS THIS WOULD BE CONFINED TO THE MORE SHELTERED AREAS, ZONES WHERE THE GROWING SEASON HAS NOT BEEN DECLARED STARTED AND ALSO WHERE THERE IS LESS INFLUENCE FROM THE ONSHORE FLOW. THEREFORE, NO MENTION INCLUDED IN THE FORECAST. THE HOURLY GRIDS WERE ADJUSTED BASED ON THE LATEST OBSERVATIONS WITH SOME BLENDING IN OF THE LAMP/LAV GUIDANCE. THERE IS A MORE NOTABLE DEW POINT GRADIENT CLOSE TO INTERSTATE 95 GIVEN THE AFOREMENTIONED SEA BREEZE BOUNDARY, THEREFORE THE DEW POINTS WERE ADJUSTED AS WELL. NO MAJOR CHANGES MADE TO THE LOW TEMPERATURES ATTM. && .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 /01Z SUNDAY THROUGH THURSDAY/... THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY AND SURROUNDING AREAS. OVERNIGHT...VFR, HIGH LEVEL CEILINGS GRADUALLY THINNING TO THE SOUTH AND EAST LATE. LIGHT NORTHERLY OR LIGHT AND VARIABLE WINDS, BECOMING NORTHEAST 5 TO 10 KNOTS. THE WINDS MAY INCREASE SOME TOWARD DAYBREAK ESPECIALLY FOR AREAS CLOSER TO THE COAST. SUNDAY...VFR. NORTHEAST TO EAST WINDS AROUND 10 KNOTS, THEN LOCALLY TURNING TO THE SOUTHEAST LATER IN THE AFTERNOON. SOME GUSTS TO AROUND 20 KNOTS ARE EXPECTED FROM THE KPHL METRO AREA SOUTH AND EASTWARD, WITH THE HIGHEST GUSTS AT KACY. 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 4-5 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...GORSE/IOVINO NEAR TERM...GIGI/GORSE SHORT TERM...GIGI LONG TERM...IOVINO AVIATION...GORSE/IOVINO MARINE...GIGI/IOVINO FIRE WEATHER...GIGI

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