NWS Philadelphia/Mount Holly wrote its last area forecast discussion before the first event at Feb 15, 5:46 AM EST, 4 hours 14 minutes earlier.
Area forecast discussion, Feb 15, 5:46 AM EST, 4 hours 14 minutes before
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
546 AM EST MON FEB 15 2016
.SYNOPSIS...
HIGH PRESSURE LOCATED OVER NEW ENGLAND EARLY THIS MORNING WILL
MOVE OUT TO SEA TODAY. MEANWHILE, LOW PRESSURE IS FORECAST TO
DEVELOP OVER THE LOWER MISSISSIPPI AND TENNESSEE RIVER VALLEYS.
THE STRENGTHENING LOW IS EXPECTED TO MOVE NORTHEASTWARD AND IT
SHOULD PASS OVER CENTRAL MARYLAND AND EASTERN PENNSYLVANIA ON
TUESDAY. THE LOW IS ANTICIPATED TO MOVE UP INTO EASTERN CANADA FOR
LATE TUESDAY NIGHT AND WEDNESDAY. A COLD FRONT FROM THE NORTHWEST
IS FORECAST T0 ARRIVE ON WEDNESDAY NIGHT WITH HIGH PRESSURE
ARRIVING IN ITS WAKE FOR THURSDAY AND FRIDAY. LOW PRESSURE PASSING
TO OUR NORTH IS EXPECTED TO PULL A WARM FRONT THROUGH OUR REGION
ON FRIDAY NIGHT, FOLLOWED BY A COLD FRONT LATE ON SATURDAY.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
BASED OFF OF CURRENT RADAR TRENDS AND LATEST GUIDANCE, WE'VE
INCREASED SNOW AMOUNTS ACROSS SOUTHERN NEW JERSEY AND ADDED
THEM INTO THE WINTER WEATHER ADVISORY. OVER THE NEXT FEW HOURS
WITH THE FIRST ROUND OF SNOW, THESE AREAS COULD GET AN INCH OR TWO
OF SNOW, ALONG WITH THE CENTRAL/SOUTHERN DELMARVA.
WE'VE ALSO ADDED THE REMAINDER OF INLAND NEW JERSEY, BASICALLY
AREAS ALONG THE NJ TURNPIKE, TO THE WINTER WEATHER ADVISORY AS WE
EXPECT THERE COULD BE A AN HOUR OR TWO OF OF FREEZING RAIN LATER
TODAY AS THE PRECIPITATION BEGINS TO CHANGE OVER.
HIGH PRESSURE ACROSS THE NORTHERN AREAS EARLY THIS MORNING WILL
CONTINUE TO RETREAT THROUGH THE MORNING AS A WARM FRONT APPROACHES
FROM THE SOUTH, WHICH WILL ALLOW THE MOISTURE TO PUSH NORTHWARD,
EVENTUALLY ALLOWING THE SNOWFALL TO SPREAD ACROSS THE ENTIRE AREA
LATER THIS MORNING INTO THE AFTERNOON. TEMPERATURES WILL REMAIN
COLD ENOUGH FOR SNOW FOR MUCH OF THE MORNING, BEFORE WARM AIR
STARTS TO PUSH INLAND FROM THE SOUTH AND EAST THIS AFTERNOON. A
CHANGE FROM SNOW, TO SNOW/SLEET, TO SLEET/RAIN, AND THEN ALL RAIN
SHOULD TAKE PLACE FROM EAST TO WEST DURING THE AFTERNOON. THE
PORTIONS OF THE WINTER WEATHER ADVISORY ALONG THE DELAWARE
RIVER/I-95 CORRIDOR MAY BEGIN MIXING WITH FREEZING RAIN LATER IN
THE AFTERNOON. GENERALLY AROUND ONE TO TWO INCHES OF SNOW IS
EXPECTED DURING THE DAYTIME HOURS ACROSS MUCH OF THE AREA TODAY.
FOR THE AREAS OF NEW JERSEY OUTSIDE OF THE ADVISORY, WE EXPECT
SNOW DURING THE MORNING HOURS. HOWEVER, WE ARE ONLY EXPECTING
AROUND AN INCH OR LESS BEFORE THE MIX WITH RAIN AND SLEET OCCURS.
THEREFORE THE ADVISORY WAS NOT EXPANDED INTO THE REMAINDER OF NEW
JERSEY.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM TUESDAY/...
AS WE MOVE INTO THE EVENING, THE WARM AIR WILL CONTINUE TO PUSH
WESTWARD AS THE LIFTING WARM FRONT SURGES NORTHWARD. WE EXPECT
MOSTLY RAIN TO BE ONGOING THIS EVENING FROM THE I-95 CORRIDOR
SOUTHWARD, WITH THE SNOW AND WINTRY MIX NORTHWARD. EVENTUALLY THE
WINTRY MIX WITH BE REPLACED BY RAIN ACROSS THE ENTIRE AREA. AS THE
CHANGE OVER TO RAIN OCCURS, SOME AREAS WILL BE BELOW FREEZING,
ALLOWING FREEZING RAIN TO OCCUR. THE AREAS ACROSS THE FAR NORTH
WILL TAKE THE LONGEST TO WARM ABOVE FREEZING, BUT SHOULD DO SO
OVERNIGHT. AN ADDITIONAL ONE TO THREE INCHES OF SNOW/SLEET IS
POSSIBLE DURING THE EVENING AND OVERNIGHT HOURS, IN ADDITION TO A
LIGHT GLAZE OF ICE BEFORE THE CHANGE OVER TO ALL RAIN.
WE TRIED TO TIME THE ENDING OF THE ADVISORIES BASED ON THE
EXPECTED CHANGE OVER TO ALL RAIN AND TEMPERATURES RISING ABOVE
FREEZING.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
THE CENTER OF THE LOW IS FORECAST TO BE AROUND SOUTHWESTERN
VIRGINIA NEAR DAYBREAK ON TUESDAY. IT IS EXPECTED TO PASS ACROSS
CENTRAL MARYLAND AND EASTERN PENNSYLVANIA DURING THE LATE MORNING
TO MID AFTERNOON HOURS. A 65+ KNOT LOW LEVEL JET AHEAD OF THE
SYSTEM WILL CONTINUE TO DRAW MILD AIR AND MOISTURE INTO OUR
REGION. PRECIPITABLE WATER VALUES SHOULD RISE ABOVE 1 INCH IN MUCH
OF OUR FORECAST AREA FOR A TIME CENTERED ON LATE TUESDAY MORNING
AND EARLY TUESDAY AFTERNOON.
IT APPEARS AS THOUGH TEMPERATURES WILL BE ABOVE FREEZING AT
DAYBREAK ON TUESDAY THROUGHOUT OUR FORECAST AREA, SO WILL SHOULD
BE DEALING WITH ONLY RAIN ON TUESDAY. THE RAIN WILL BE MODERATE TO
HEAVY AT TIMES, ESPECIALLY DURING THE HOURS AROUND NOON. THE
LATEST GUIDANCE SUGGESTS RAINFALL TOTALS FOR TUESDAY WILL BE IN
THE 0.5 TO 1.0 INCH RANGE IN EASTERN PENNSYLVANIA AND NORTHERN NEW
JERSEY, AND IN THE 0.25 TO 0.75 INCH RANGE IN NORTHEASTERN
MARYLAND, DELAWARE, AND SOUTHERN AND CENTRAL NEW JERSEY. WHILE THE
EXPECTED AMOUNTS HAVE COME DOWN SLIGHTLY, WE REMAIN CONCERNED WITH
THE POTENTIAL FOR SOME SMALL STREAM AND POOR DRAINAGE AREA
FLOODING. THE DETAILS ARE DISCUSSED IN THE HYDROLOGY SECTION
BELOW.
MAXIMUM TEMPERATURES ARE ANTICIPATED TO FAVOR THE 50S ON TUESDAY,
WITH READINGS NOT GETTING ABOVE THE 40S IN OUR NORTHWESTERN
COUNTIES. REGARDLESS, IT WILL BE QUITE A CONTRAST TO THE LAST
COUPLE OF DAYS.
AS THE LOW MOVES UP ACROSS EASTERN NEW YORK AND WESTERN NEW
ENGLAND, THEN INTO QUEBEC ON TUESDAY NIGHT, THE RAIN WILL LIKELY
COME TO AN END IN OUR REGION.
A WEAK MID LEVEL DISTURBANCE MAY BRING SOME LIGHT RAIN SHOWERS TO
OUR SOUTHERN COUNTIES LATE ON TUESDAY NIGHT.
A COLD FRONT IS FORECAST TO APPROACH FROM THE NORTHWEST ON
WEDNESDAY AND IT IS EXPECTED TO ARRIVE ON WEDNESDAY NIGHT. THE
FEATURE IS NOT FORECAST TO HAVE MUCH MOISTURE ASSOCIATED WITH IT.
HIGH PRESSURE IS ANTICIPATED TO FOLLOW IN ITS WAKE FOR THURSDAY
AND FRIDAY. THE HIGH SHOULD BRING DRY WEATHER AND SEASONABLE
TEMPERATURES.
LOW PRESSURE IS FORECAST TO PASS TO OUR NORTH FROM LATE FRIDAY
NIGHT INTO SATURDAY. IT IS EXPECTED TO PULL A WARM FRONT THROUGH
OUR REGION ON FRIDAY NIGHT, FOLLOWED BY A COLD FRONT LATE ON
SATURDAY. WE WILL INCLUDE A CHANCE OF LIGHT RAIN, MAINLY ACROSS
THE NORTHERN HALF OF OUR FORECAST AREA. THERE COULD BE SOME
POCKETS OF BELOW FREEZING TEMPERATURES UP NORTH ON FRIDAY NIGHT,
SO WE WILL MENTION THE POTENTIAL FOR A BIT OF FREEZING RAIN THERE
AT THAT TIME.
HIGH PRESSURE SHOULD BRING A RETURN TO DRY WEATHER CONDITIONS FOR
SUNDAY.
&&
.AVIATION /12Z MONDAY THROUGH FRIDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY AND SURROUNDING AREAS.
VFR CONDITIONS EARLY THIS MORNING WILL BE REPLACED BY MVFR AND
IFR CONDITIONS AS SNOWFALL SPREADS NORTHWARD ACROSS THE TAF SITES.
PRECIPITATION WILL START AS ALL SNOW, BEFORE MIXING WITH SLEET
DURING THE AFTERNOON AND EVENING. SNOW AND SLEET WILL THEN CHANGE
OVER TO RAIN FOR ACY/MIV LATE THIS AFTERNOON. A HOURS OR TWO OF
FREEZING RAIN/SLEET MAY OCCUR FOR ILG/PHL/PNE/TTN DURING THE
EVENING HOURS, BUT IS MORE LIKELY FOR RDG/ABE THIS EVENING.
EVERYONE IS EXPECTED TO CHANGE OVER TO ALL RAIN BY THIS EVENING
AND OVERNIGHT AS WARMER AIR SURGES NORTHWARD ACROSS THE AREA.
WINDS THROUGH TODAY WILL GENERALLY BE EAST TO SOUTHEAST AROUND 5
TO 10 KNOTS. WINDS MAY BECOME MORE SOUTHERLY OVERNIGHT AS A WARM
FRONT LIFTS NORTH OF THE AREA.
OUTLOOK...
TUESDAY...MVFR AND IFR CONDITIONS WITH RAIN MODERATE TO HEAVY AT
TIMES. SOME IMPROVEMENT IS POSSIBLE LATE IN THE DAY. THERE IS THE
POTENTIAL FOR LOW LEVEL WIND SHEAR DUE TO THE PRESENCE OF A 65+
KNOT LOW LEVEL SOUTHERLY JET.
TUESDAY NIGHT THROUGH FRIDAY...MAINLY VFR.
&&
.MARINE...
SUB-ADVISORY CONDITIONS WILL REMAIN ACROSS THE WATERS TODAY.
HOWEVER, WINDS ARE EXPECTED TO INCREASE THIS EVENING AND OVERNIGHT
AS THE PRESSURE GRADIENT INCREASES ACROSS THE AREA BEHIND A
LIFTING WARM FRONT AND AHEAD OF AN APPROACHING LOW PRESSURE
SYSTEM. SEAS WILL ALSO BUILD OVERNIGHT WITH THE INCREASING
SOUTHERLY FLOW.
OUTLOOK...
TUESDAY...A SMALL CRAFT ADVISORY IS IN EFFECT WITH SOUTH TO
SOUTHWEST WIND GUSTS OF 25 TO 30 KNOTS EXPECTED. THERE IS THE
POTENTIAL FOR GALE FORCE GUSTS, AS WELL.
TUESDAY NIGHT...WIND SPEEDS SHOULD DECREASE. HOWEVER, WAVE
HEIGHTS WILL LIKELY REMAIN IN THE 6 TO 10 FOOT RANGE ON OUR OCEAN
WATERS. A SMALL CRAFT ADVISORY REMAINS IN EFFECT FOR OUR OCEAN
WATERS UNTIL 600 AM WEDNESDAY. THE SMALL CRAFT ADVISORY REMAINS IN
EFFECT FOR LOWER DELAWARE BAY UNTIL MIDNIGHT.
WEDNESDAY...WAVE HEIGHTS ON OUR OCEAN WATERS MAY REMAIN IN THE 4
TO 6 FOOT RANGE.
WEDNESDAY NIGHT AND THURSDAY...THERE IS THE POTENTIAL FOR
NORTHWEST WIND GUSTS OF 25 TO 30 KNOTS.
THURSDAY NIGHT AND FRIDAY...NO MARINE HEADLINES ARE ANTICIPATED.
&&
.HYDROLOGY...
WE CONTINUE TO BE CONCERNED ABOUT THE POTENTIAL FOR LOCALIZED
FLOODING ON TUESDAY WITH THE EXPECTED ARRIVAL OF A PERIOD OF
MODERATE TO HEAVY RAINFALL.
LIQUID PRECIPITATION TOTALS FOR THE ENTIRE EARLY WEEK EVENT ARE
FORECAST TO FAVOR THE 1.0 TO 1.5 INCH RANGE IN MUCH OF EASTERN
PENNSYLVANIA AND NORTHERN NEW JERSEY. WHILE THE PRECIPITATION
SHOULD FALL AS SNOW AND ICE DURING TODAY AND PART OF TONIGHT,
WARMING TEMPERATURES AND THE ARRIVAL OF THE MODERATE TO HEAVY
RAINFALL WILL CAUSE MUCH OF THE SNOW AND ICE TO MELT. SMALL
STREAMS ARE ALREADY RUNNING A BIT HIGH, SO THE RAINFALL AND RUNOFF
FROM THE MELTED SNOW AND ICE COULD CAUSE SOME SMALL STREAM
FLOODING. ALSO, THE RAINFALL ALONG WITH THE POTENTIAL THAT STORM
DRAINS WILL BE BLOCKED BY SNOW, ICE AND DEBRIS COULD RESULT IN
FLOODING OF ROADWAYS AND AREAS OF POOR DRAINAGE.
THE MODERATE TO HEAVY RAINFALL SHOULD IMPACT PARTS OF
NORTHEASTERN MARYLAND, DELAWARE AND SOUTHERN AND CENTRAL NEW
JERSEY, AS WELL. HOWEVER, LIQUID PRECIPITATION AMOUNTS ARE
FORECAST TO BE A BIT LOWER THERE, PERHAPS IN THE 0.75 TO 1.25 INCH
RANGE. NEVERTHELESS, SOME SMALL STREAM AND POOR DRAINAGE AREA
FLOODING IS POSSIBLE.
DEPENDING UPON THE ACTUAL RAINFALL AMOUNTS AND HOW THE RUNOFF
REACTS, FLOODING MAY LINGER INTO TUESDAY NIGHT AND WEDNESDAY WITH
NOTICEABLE RISES POSSIBLE ON SOME OF THE MAIN STEM RIVERS.
&&
.TIDES/COASTAL FLOODING...
THE RECENT STRONG NORTHWESTERLY FLOW HAS PUSHED WATER AWAY FROM
THE COAST AND WATER LEVELS ARE QUITE LOW EARLY THIS MORNING.
THE MOON IS AROUND ITS FIRST QUARTER PHASE, SO ASTRONOMICAL TIDES
WILL BE LOW. THE EAST TO SOUTHEAST ONSHORE FLOW IS EXPECTED TO BE
SHORT LIVED, GENERALLY LASTING ONLY TODAY, SO THE POTENTIAL FOR
EVEN MINOR FLOODING ALONG THE COASTS OF NEW JERSEY AND DELAWARE IS
LOW WITH THE UPCOMING WEATHER SYSTEM.
THE DEVELOPMENT OF A MODERATE SOUTHERLY FLOW FOR TONIGHT INTO
TUESDAY SHOULD PUSH WATER UP CHESAPEAKE BAY AND UP DELAWARE BAY
AND INTO THE TIDAL DELAWARE RIVER. HOWEVER, MOST OF THE AVAILABLE
GUIDANCE STILL SUGGESTS THAT NO FLOODING WILL OCCUR. THE ONLY
OUTLIER REMAINS THE ESTOFS MODEL WHICH SUGGESTS MINOR FLOODING ON
UPPER CHESAPEAKE BAY. WE WILL CONTINUE TO MONITOR.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...WINTER WEATHER ADVISORY FROM 10 AM THIS MORNING TO 1 AM EST
TUESDAY FOR PAZ060>062-101-103-105.
WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
PAZ070-071-102-104-106.
WINTER WEATHER ADVISORY FROM 1 PM THIS AFTERNOON TO 4 AM EST
TUESDAY FOR PAZ054-055.
NJ...WINTER WEATHER ADVISORY FROM 10 AM THIS MORNING TO 1 AM EST
TUESDAY FOR NJZ007>010.
WINTER WEATHER ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR
NJZ021>025-027.
WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
NJZ012-013-015>020.
WINTER WEATHER ADVISORY FROM 1 PM THIS AFTERNOON TO 4 AM EST
TUESDAY FOR NJZ001.
DE...WINTER WEATHER ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR
DEZ002>004.
WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
DEZ001.
MD...WINTER WEATHER ADVISORY UNTIL 4 PM EST THIS AFTERNOON FOR
MDZ012-015-019-020.
WINTER WEATHER ADVISORY UNTIL 10 PM EST THIS EVENING FOR
MDZ008.
MARINE...SMALL CRAFT ADVISORY FROM 7 PM THIS EVENING TO 6 AM EST
WEDNESDAY FOR ANZ450>455.
SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO 6 PM EST TUESDAY
FOR ANZ430.
SMALL CRAFT ADVISORY FROM MIDNIGHT TONIGHT TO MIDNIGHT EST
TUESDAY NIGHT FOR ANZ431.
&&
SYNOPSIS...IOVINO
NEAR TERM...ROBERTSON
SHORT TERM...ROBERTSON
LONG TERM...IOVINO
AVIATION...IOVINO/ROBERTSON
MARINE...IOVINO/ROBERTSON
HYDROLOGY...IOVINO
TIDES/COASTAL FLOODING...IOVINO