A deep low pressure system tracked across the Lower Great Lakes northeastward into the St. Lawrence Valley from the evening of the 20th into the daytime of the 21st.
Every event with a place to put it; 5 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS PHI wrote it up.
A deep low pressure system tracked across the Lower Great Lakes northeastward into the St. Lawrence Valley from the evening of the 20th into the daytime of the 21st. Its associated strong cold front swept eastward through the Mid Atlantic region and across Delaware during the early morning of the 21st. In addition, a secondary area of low pressure formed along the frontal boundary, west of Delaware Bay, and deepened rapidly. The approaching cold front and the deepening secondary low pressure produced a strong southeasterly flow over the region that resulted in peak southeast wind gusts ranging from 45 mph to 60 mph across the state during the early morning on the 21st. The wind damaged trees, tree limbs and knocked down power lines. Most of the reported downed trees were in New Castle County. Delmarva Power reported about 650 of its customers lost power, 500 of them were in New Castle County. Peak wind gusts included 60 mph at the New Castle County Airport, 48 mph in Georgetown (Sussex County) and 45 mph in Lewes (Sussex County) and Dover (Kent County).
In addition, the significant southeast flow allowed water to pile up along the Delaware Coast and into Delaware Bay, producing minor to major coastal flooding at the time of high tide on the morning of the 21st. The magnitude of the tidal flooding increased northwestward through Delaware Bay into tidal sections of the Delaware River. Moderate to heavy rain fell across the state, with storm totals ranging between 1 to 3 inches. This rain resulted in minor to moderate flooding of creeks and rivers in Northern Delaware.
The strong onshore flow contributed to higher high tides with minor tidal flooding occurring along the Delaware oceanfront. High tide at Breakwater Harbor (Sussex County) reached 6.67 feet above mean lower low water. Minor tidal flooding starts at 6.0 feet above mean lower low water. The southeasterly flow pushed water up the Delaware Bay and into the tidal portions of the Delaware River, causing major tidal flooding to occur at Reedy Point (New Castle County). High tide at Reedy Point reached 9.2 feet above mean lower low water. Major tidal flooding starts at 9.2 feet above mean lower low water. The high tide reached 9.47 feet above mean lower low water at Delaware City (New Castle County). There are no established flood categories for this site. Because of tidal effects from Chesapeake Bay which extended east through the Nanticoke River, the Woodland Ferry (in Sussex County) canceled operations on the 21st.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Philadelphia/Mount Holly wrote its last area forecast discussion before the first event at Dec 21, 12:51 AM EST, 9 minutes earlier.
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1251 AM EST FRI DEC 21 2012
.SYNOPSIS...
A POTENT AREA OF LOW PRESSURE WILL TRACK ACROSS THE GREAT LAKES AND
NORTHEAST TONIGHT AND FRIDAY, THEN ACROSS EASTERN CANADA DURING THE
WEEKEND. ITS ASSOCIATED STRONG COLD FRONT WILL SWEEP ACROSS OUR
REGION EARLY FRIDAY MORNING. A WEAK AREA OF HIGH PRESSURE THEN
BUILDS DOWN INTO OUR REGION LATE SUNDAY AND MONDAY. A WEAK LOW
PRESSURE SYSTEM MAY AFFECT OUR AREA MONDAY NIGHT INTO TUESDAY, WITH
THE POTENTIAL FOR A MUCH STRONGER STORM SET TO ARRIVE ON THURSDAY.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
STARTING IN THE POCONOS, WE ARE PLANNING ON LETTING THE ADVY
EXPIRE AT 11 PM. THE DRY AIR ALOFT HAS EVAP COOLED AND THE
FREEZING RAIN IN THE HIGHER TERRAIN HAS CHANGED TO SNOW. THE
NUMBER OF MESONET SITES BELOW FREEZING WHICH ONCE WAS AROUND 20 IS
DOWN TO 6. HRRR AND LATEST WRF-NMMB HAS EVERYONE ABOVE FREEZING BY
03Z. SOME SLIPPERY SPOTS WERE REPORTED IN THE HIGHER TERRAIN OF
MONROE COUNTY AND AROUND A QUARTER INCH OF SNOW IN PLACES.
NOW FOR THE OTHER WEATHER HAZARD, THE WIND. NOT AN EASY DECISION
BECAUSE THE SOUNDINGS ARE NEARLY ISOTHERMAL WITH POOR LAPSE RATES.
THE 00Z SOUNDINGS SUPPORTED A COMP BETWEEN THE WRF-NMMB AND GFS
FCST SPEEDS. SINCE THEN THE VWP LOOK OK AT KAKQ AND KLWX FOR THE
NEW WRF-NMMB 925MB WINDS, BUT THE MODEL IS RUNNING AROUND 5 TO
10 KTS TOO HOT AT 850MB. SO FAR THE MIXING OF STRONGER WINDS IN
THE CAROLINAS HAS BEEN SPORADIC. SO WHAT WE CAN GATHER THERE HAVE
NOT BEEN UPSIDE SURPRISES YET. THE OVERALL WIND FIELDS ARE
FORECAST THOUGH TO INTENSIFY FURTHER AS TIME GOES ON TONIGHT AND
THE MOMENTUM TRANSFER WINDS ON OCCASION ARE MIXING ADVY LEVEL WIND
GUSTS DOWN. THE MESOSCALE MODELS AND WE DONT KNOW IF THEY ARE THIS
GOOD ARE NOT FORECASTING A SINGLE NCFRB TOWARD MORNING. AFTER
COORD WITH OKX AND LOOKING AT THE 12/1/10 ANALOG THEY FOUND (WHICH
WAS AN ADVY TYPE EVENT CENTERED MAINLY IN THE ERN PART OF OUR
CWA), WE DECIDED TO ISSUE A WIND ADVY THAT COINCIDES CLOSEST WITH
THE 70KT OR GREATER ISOTACH ON THE LATEST WRF-NMMB. WE INCLUDED
ALL OF DELAWARE BAY BECAUSE OF THE SE FLOW. IF A NCFRB DOES FORM
NEAR THE JET MAX, THE ADVY MAY NEED TO BE UPGRADED OR EXPANDED.
RIGHT NOW CONFIDENCE IS TOO LOW TO ISSUE.
THE REST OF THE FCST WAS KEPT PRETTY MUCH AS IS, MOST OF THE
HEAVIEST PCPN IS EXPECTED TO FALL AFTER MIDNIGHT AND END RATHER
QUICKLY WITH THE CFP AROUND 12Z.
OTHER THAN SOME NUISANCE FLOODING, NO HYDRO ISSUES ARE EXPECTED.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM SATURDAY/...
A THREAT OF RAIN SHOULD STILL EXIST FOR THE NORTHERN ZONES EARLY
TOMORROW MORNING. THEN WHEN THE UPPER LOW AND COLD POOL ALOFT MOVES
CLOSER, A SHOWER ANYWHERE CAN'T BE RULED OUT. TEMP PROFILES
SUGGEST SNOW SHOWERS FAR NORTH AND WEST.
TEMPS WILL HOLD STEADY OR FALL THROUGH THE 40S (30S NORTH AND WEST)
TOMORROW WITH WINDS GUSTING TO 30 OR 40 MPH.
LITTLE TO NO ACCUMULATION IS EXPECTED WHERE THE FLAKES FLY.
&&
.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
A RATHER ACTIVE PATTERN LOOKS TO CONTINUE. THE OVERALL SYNOPTIC FLOW
IS COMPRISED OF A DEEP TROUGH OVER THE EAST FRIDAY NIGHT AND
SATURDAY, THEN ADDITIONAL ENERGY PUSHING INTO THE WEST ALLOWS
DOWNSTREAM RIDGING TO KICK THE TROUGH INTO CANADA WHERE IT TENDS TO
BECOME ELONGATED WEST TO EAST. A PIECE OF ENERGY ROTATING AROUND
THIS MAY ALLOW FOR A SHORT WAVE TROUGH TO SLIDE ACROSS THE GREAT
LAKES INTO THE NORTHEAST AROUND TUESDAY. A MUCH MORE PRONOUNCED
UPPER-LEVEL TROUGH THEN LOOKS TO EJECT OUT OF THE FOUR CORNERS
REGION TUESDAY NIGHT INTO WEDNESDAY. THIS FEATURE ALONG WITH A
DEEPENING SURFACE LOW IS THEN FORECAST TO MOVE THROUGH THE EAST NEXT
THURSDAY. OVERALL, THE MODEL GUIDANCE CONTINUES TO SHOW VARIABILITY
WITH TIMING AND SPACING OF EMBEDDED INDIVIDUAL FEATURES HOWEVER
CONTINUED SUPPORT FOR AN ACTIVE PATTERN. THE THERMAL GRADIENTS AND
AMPLITUDE OF THE PATTERN MAY BE PLAYING A ROLE WITH THE MODEL
VARIABILITY. IT APPEARS THERE IS AN INCREASING SIGNAL FOR AN EAST
COAST STORM DURING ABOUT THE SECOND HALF OF NEXT WEEK. OF COURSE
THIS FAR OUT, THE DETAILS ARE MUCH LESS CERTAIN AND THEREFORE MUCH
LOWER CONFIDENCE IN THE FORECAST BEYOND TUESDAY ESPECIALLY.
FOR FRIDAY NIGHT AND SATURDAY...AN INTENSE STORM IS FORECAST TO BE
IN THE SOUTHEAST CANADA AND NEW ENGLAND AREAS DURING THIS TIME
FRAME. IT WILL BE DRIVEN BY A SHARP UPPER-LEVEL TROUGH WITH A SHOT
OF MUCH COLDER AIR ALONG WITH IT. A RATHER DEEP CYCLONIC FLOW REGIME
WILL BE OCCURRING WITH THE POTENTIAL FOR SOME WRAPAROUND SNOW
SHOWERS, AND THE LAKE EFFECT SNOW MACHINE SHOULD BE IN HIGH GEAR. AS
THE CAA CONTINUES, SHORT WAVE ENERGY ROTATING AROUND THE PARENT
UPPER-LEVEL TROUGH SHOULD HELP TO MAINTAIN SOME SNOW SHOWERS INTO
OUR NORTHWEST ZONES. SOME OF THE MODEL GUIDANCE SHOWING SIGNS OF
CHANNELIZED VORTICITY ORIENTATED NORTHWEST TO SOUTHEAST. IF DEEP
ENOUGH MOISTURE CAN BE MAINTAINED AND ENOUGH LIFT/INSTABILITY CAN
OCCUR WITHIN THE NORTHWEST FLOW, SOME LOCALIZED SNOW SQUALLS MAY
OCCUR ACROSS NORTHEASTERN PENNSYLVANIA AND NORTHWESTERN NEW JERSEY.
WE WOULD LIKE TO SEE BETTER ORGANIZATION OF THE CHANNELIZED
VORTICITY TO INCREASE CONFIDENCE REGARDING LAKE EFFECT STREAMERS
REMAINING INTACT THIS FAR SOUTHEAST FROM THE LAKES. FOR NOW, WE
CARRIED LOW LIKELY POPS ACROSS THE POCONOS AND TOWARD FAR NORTHWEST
NEW JERSEY, THEN POPS TAPER WITH A SOUTHEASTWARD EXTENT. BEYOND THE
SLIGHT CHC POPS, WE CARRIED SCATTERED FLURRIES DOWN TO THE
INTERSTATE 95 CORRIDOR. SOME PLACES PARTICULARLY IN THE POCONOS
COULD PICK UP AN INCH OR TWO OF SNOW. FARTHER SOUTHEAST, WHILE A FEW
HEAVIER SNOW SHOWERS MAY BE ABLE TO OCCUR, THE DOWNSLOPING FLOW MAY
PROVIDE ENOUGH EXTRA DRYING TO ERODE THESE. THIS IS OF LOWER
CONFIDENCE THEREFORE DID NOT BRING THE SNOW SHOWER MENTION EVEN
FARTHER SOUTHEAST AND WENT WITH FLURRIES.
ANOTHER FORECAST CONCERN IS THE STRONG WIND POTENTIAL. A RATHER
TIGHT PRESSURE GRADIENT IS FORECAST TO REMAIN ACROSS OUR ENTIRE. THE
CAA COMBINED WITH THE TIGHT PRESSURE GRADIENT SHOULD KEEP THE SURFACE
WINDS GOING FRIDAY NIGHT DESPITE LESSENING VERTICAL MIXING AT TIMES.
THE VERTICAL MIXING IS MUCH MORE PRONOUNCED SATURDAY AS THE AIRMASS
IS CHILLY, THE LOW-LEVEL LAPSE RATES STEEPEN SOME MORE AND THERE IS
PLENTY OF WIND NOT TO FAR ABOVE THE SURFACE. THE FORECAST SOUNDINGS
GET CLOSE TO 40 KNOTS POTENTIALLY MIXING DOWN TO THE SURFACE,
ALTHOUGH THE GFS IS MORE ROBUST WITH THIS AS IT SUGGESTS NEARLY
50 KNOTS MIXING DOWN TO THE SURFACE. THE 925 MB WINDS ARE NOT AS
STRONG ON THE ECMWF WITH AROUND 40 KNOTS FORECAST SATURDAY
ESPECIALLY ACROSS THE SOUTHERN HALF OF OUR CWA. WE THOUGHT ABOUT
GOING WITH A HIGH WIND WATCH WITH THE GREATER CHC ACROSS ABOUT THE
SOUTHERN HALF OF THE CWA, HOWEVER THIS IS NEARLY TWO DAYS OUT. IT
MAY END UP BEING A WIND ADVISORY TYPE EVENT THEREFORE WE DECIDED TO
HOLD OFF ON ANY HEADLINES ATTM. WE HOWEVER WILL CONTINUE A
MENTION IN THE HAZARDOUS WEATHER OUTLOOK. WE INCREASED THE WINDS
SOME /ESPECIALLY GUSTS/ FOR SATURDAY FROM CONTINUITY WITH GUSTS
GENERALLY IN THE 40-45 MPH RANGE. AS FOR HIGH AND LOW TEMPERATURES,
WE GENERALLY TOOK AN EVEN BLEND OF THE NAM/GFS MOS.
FOR SUNDAY AND MONDAY /CHRISTMAS EVE/...THE POTENT STORM IS FORECAST
TO MOVE UP THROUGH THE CANADIAN MARITIMES, HOWEVER A TIGHTENED
PRESSURE GRADIENT GENERALLY REMAINS IN PLACE. THE OVERALL FLOW
THOUGH WILL BE LESSENING, HOWEVER VERTICAL MIXING WILL PROVIDE
ENOUGH FOR A BRISK DAY ON SUNDAY. IT APPEARS THAT WITHIN THE
NORTHWESTERLY FLOW, A SHORT WAVE ROTATING AROUND THE PARENT STORM
MAY TOSS A SURFACE TROUGH OR COLD FRONT TOWARD OUR REGION. THE LAKE
EFFECT SNOW MACHINE SHOULD BE WINDING DOWN SUNDAY AS THE CAA WANES
SOME AND THE LOW-LEVEL FLOW MAY TURN MORE WESTERLY.
A SHORT WAVE TRAVERSING THE NORTHERN TIER CHRISTMAS EVE MAY ALLOW
FOR A SURFACE LOW REFLECTION TO RACE OUT AHEAD OF THE DEEPENING
TROUGH IN THE WEST. SOME MOISTURE RETURN AHEAD OF IT ALONG WITH WAA,
MAY RESULT IN AN AREA OF OVERRUNNING PRECIPITATION. THERE IS A
QUESTION REGARDING HOW DRY THE AIRMASS IS OVER OUR AREA AND THE
STRENGTH OF THE OVERALL LIFT. A LIGHT INTENSITY OF THE PRECIPITATION
MAY PLAY MORE OF A ROLE, WITH EVEN DEPENDING ON HOW THE BOUNDARY
LAYER BEHAVES. FOR NOW WE WILL FAVOR SLIGHT CHC POPS FOR A WEAK
OVERRUNNING POTENTIAL AND GO RAIN AND/OR SNOW.
FOR TUESDAY...THE AFOREMENTIONED FRONT RUNNER WEAKER SURFACE WAVE
SHOULD SCOOT OUT TO SEA EARLY TUESDAY AS THE SHORT WAVE TROUGH MAY
END UP DAMPENING OUT SOME. WHILE THERE COULD BE SOME RESIDUAL LIGHT
PRECIPITATION AROUND TO START TUESDAY, WE SIMPLY FAVORED SLIGHT CHC
POPS IN THE MORNING GIVEN LOWER CONFIDENCE ON TIMING AND OF ANY MORE
ORGANIZED LIFT.
FOR WEDNESDAY AND THURSDAY...THE PATTERN ONCE AGAIN STARTS TO REALLY
RAMP UP WEDNESDAY AS ENERGY FROM THE FOUR CORNERS REGION SLIDES
ACROSS THE PLAINS AND THEN THE TENNESSEE VALLEY. THERE IS ANOTHER
SYSTEM UP IN THE CANADIAN MARITIMES OVERALL, WHICH WOULD TEND TO
LEAD TO BLOCKING. THIS DEVELOPING PATTERN IS LOOKING MORE CONDUCIVE
FOR A COASTAL STORM TO OCCUR. IN THIS UPCOMING POTENTIAL, THE
INITIAL SURFACE LOW MAY TRACK UP THE OHIO VALLEY BUT THEN WEAKEN.
HIGH PRESSURE POSITIONED OVER EASTERN CANADA, IF IT CAN BE
MAINTAINED, MAY HELP TO WEDGE A COLDER LOW-LEVEL AIRMASS SOUTHWARD
ACROSS AT LEAST PORTIONS OF OUR AREA. THIS COLD AIR DAMMING SCENARIO
WOULD OPEN THE DOOR FOR SURFACE LOW REDEVELOPMENT NEAR THE VIRGINIA
COAST AS THE BAROCLINICITY TIGHTENS UP DUE TO THE THERMAL GRADIENT
INCREASING. THIS WOULD PROBABLY ALLOW FOR SOME WARMING ESPECIALLY
ALOFT UNTIL THE MAIN STORM GETS GOING OFF OR ALONG THE COAST.
THEREFORE, CLOUDS INCREASE WEDNESDAY AND WE WENT WITH 40-50 POPS FOR
NOW AS THE POTENTIAL IS THERE FORE A DECENT STORM. WE HELD OFF ON
GOING WITH LIKELY POPS DUE TO ENOUGH MODEL UNCERTAINTY REGARDING
TIMING AND ESPECIALLY THE DETAILS. WE WENT WITH RAIN AND/OR SNOW FOR
THE PRECIPITATION TYPE AS ANY OTHER FROZEN/FREEZING PRECIPITATION IS
MORE DEPENDENT ON THE ACTUAL THERMAL STRUCTURES.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
THE FOLLOWING DISCUSSION IS FOR KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY AND SURROUNDING AREAS.
THE 00Z TAFS CONTINUED THE DECENT INTO IFR AND LIFR AS THE
HEAVIER RAIN MOVES IN TONIGHT WITH THE LOWEST CONDITIONS AFTER
MIDNIGHT. WE ALSO CONTINUED THE MENTION OF LLWS. THE GRADIENT EAST
TO SOUTHEAST WIND ITSELF WILL ALSO INCREASE AND GUSTS TO AROUND 40
KTS ARE POSSIBLE AT TERMINALS AND AIRPORTS CLOSER TO THE OCEAN IN
NEW JERSEY AND DELAWARE.
THE COLD FRONT IS EXPECTED TO MOVE THROUGH FROM SOUTHWEST TO
NORTHEAST ACROSS OUR CWA WITH PASSAGE TIME PLUS OR MINUS OF 12Z
BY A COUPLE OF HOURS. RAPID IMPROVEMENT TO MVFR IF NOT VFR
CONDITIONS IS THEN FORECAST. WINDS THOUGH WILL REMAIN BLUSTERY,
BUT THIS TIME FROM THE WEST. CIGS SHOULD IMPROVE TO VFR BY LATE IN
THE MORNING. WINDS WILL REMAIN BRISK THROUGH THE DAY. PEAK GUSTS
OF AROUND 30 KTS ARE LIKELY.
OUTLOOK...
FRIDAY NIGHT AND SATURDAY...MAINLY VFR. WEST-NORTHWEST WINDS
SUSTAINED 15-25 KNOTS WITH GUSTS TO AROUND 35 KNOTS. THE STRONGER
WINDS SHOULD OCCUR DURING THE DAY SATURDAY. THERE COULD BE SOME
SUB-VFR CONDITIONS IN LOCAL/BRIEF SNOW SHOWERS ESPECIALLY FROM THE
KABE AND KRDG TERMINALS NORTH AND WEST.
SUNDAY...VFR WITH NORTHWESTERLY WINDS MAINLY 10-20 KNOTS.
MONDAY AND TUESDAY...VFR MONDAY ALTHOUGH CLOUDS SHOULD INCREASE AND
LOWER SOME. A WEAKER SYSTEM MAY MOVE THROUGH MONDAY NIGHT INTO
TUESDAY WITH THE CHANCE OF SOME LIGHT PRECIPITATION. LIGHT WINDS
MONDAY BECOME NORTHERLY NEAR 10 KNOTS TUESDAY.
&&
.MARINE...
A STRONG COLD FRONT WILL TRACK ACROSS OUR REGION EARLY TOMORROW
MORNING. GALES REMAIN IN PLACE FROM 700 PM TONIGHT, THROUGH THE
SHORT TERM PERIOD, AND INTO THE OUTLOOK PERIOD. SOUTHEAST WINDS
TONIGHT WILL BECOME SOUTHWEST TOMORROW. SEAS WILL RESPOND AND COULD
REACH DOUBLE DIGITS. RAIN OVERNIGHT TONIGHT WILL BECOME MOE SHOWERY
TOMORROW.
OUTLOOK...
A POTENT STORM IS FORECAST TO BE TO OUR NORTH FRIDAY NIGHT THROUGH
SATURDAY BEFORE SHIFTING INTO THE CANADIAN MARITIMES DURING THE
WEEKEND. A TIGHT PRESSURE GRADIENT IN COMBINATION WITH CAA WILL
ALLOW FOR STEEPER LOW-LEVEL LAPSE RATES AND EFFICIENT VERTICAL
MIXING. THE GFS 925 MB WINDS ARE MUCH STRONGER COMPARED TO THE NAM
AND ECMWF, HOWEVER ALL POINT TO GALE FORCE WINDS OCCURRING. THE GFS
WOULD SUGGEST A CHC FOR A PERIOD OF STORM FORCE GUSTS. WE ARE NOT
ALL THAT CONFIDENT REGARDING STORMS, THEREFORE WE WILL CONTINUE WITH
THE GALE WARNING THROUGH THE DAY SATURDAY. THE WINDS SHOULD START
DIMINISHING SATURDAY NIGHT, THEREFORE WE DECIDED NOT TO EXTEND THE
GALE WARNING ATTM. THERE SHOULD BE A PERIOD OF SMALL CRAFT ADVISORY
CONDITIONS FOLLOWING THE GALES INTO ABOUT SUNDAY. A WEAK SYSTEM MAY
THEN MOVE THROUGH MONDAY NIGHT INTO TUESDAY, HOWEVER THE WINDS AND
SEAS ARE ANTICIPATED TO BE BELOW ADVISORY CRITERIA.
&&
.TIDES/COASTAL FLOODING...
THE STRENGTHENING SOUTHEAST FLOW WILL ALLOW WATER TO PILE UP ALONG
THE COASTAL SECTIONS OF THE OCEAN...DELAWARE BAY AND CHESAPEAKE
BAY TONIGHT AND FRIDAY MORNING.
THE LATEST NUMERICAL GUIDANCE IS SHOWING THAT REEDY POINT WILL
REACH MODERATE TIDAL FLOODING WITH THE UPCOMING HIGH TIDE...A
COASTAL FLOOD WARNING HAS BEEN ISSUED. IT DOESNT APPEAR THAT THE
HIGHEST LEVELS WILL CARRY UP INTO THE TIDAL DELAWARE RIVER AT THIS
TIME...SO THE ADVISORY WILL CONTINUE THERE.
THE HIGHER DEPARTURES HAVE COME TOO LATE FOR THE HIGH TIDE AT THE
SHORE AND THE LOWER DELAWARE BAY...SO ADVISORY TYPE WATER LEVELS
ARE EXPECTED THERE...THE ONGOING CF.A WILL CONTINUE.
AS FOR THE CHESAPEAKE BAY, CURRENT DEPARTURES ARE INCREASING...BUT
THE NEXT HIGH TIDE WILL NOT OCCUR UNTIL LATER FRIDAY MORNING INTO
THE EARLY AFTERNOON HOURS...IT APPEARS THAT THE DEPARTURES WILL BE
FALLING BY THEN. BASED ON OUR NEW ADVISORY CRITERIA OF 3.8 FEET
BOTH CAMBRIDGE AND TOLCHESTER BEACH WOULD NEED AROUND A +2.5 FOOT
DEPARTURE TO REACH THE MINOR THRESHOLD. THIS COULD BE OUT OF REACH
BY THEN. WE WILL CONTINUE TO MONITOR.
&&
.PHI WATCHES/WARNINGS/ADVISORIES...
PA...COASTAL FLOOD ADVISORY UNTIL 11 AM EST THIS MORNING FOR PAZ070-
071.
NJ...WIND ADVISORY UNTIL 9 AM EST THIS MORNING FOR NJZ001-008-010-
012>014-016-020>027.
COASTAL FLOOD ADVISORY UNTIL 8 AM EST THIS MORNING FOR
NJZ012>014-020-022>027.
COASTAL FLOOD WARNING UNTIL 8 AM EST THIS MORNING FOR NJZ016-
021.
COASTAL FLOOD ADVISORY UNTIL 11 AM EST THIS MORNING FOR
NJZ017>019.
DE...WIND ADVISORY UNTIL 9 AM EST THIS MORNING FOR DEZ001>004.
COASTAL FLOOD ADVISORY UNTIL 8 AM EST THIS MORNING FOR DEZ003-
004.
COASTAL FLOOD WARNING UNTIL 8 AM EST THIS MORNING FOR DEZ001-
002.
MD...WIND ADVISORY UNTIL 9 AM EST THIS MORNING FOR MDZ015-019-020.
MARINE...GALE WARNING UNTIL 7 PM EST SATURDAY FOR ANZ430-431-450>455.
&&
SYNOPSIS...GORSE
NEAR TERM...GIGI/KRUZDLO
SHORT TERM...KRUZDLO
LONG TERM...GORSE
AVIATION...GIGI/GORSE
MARINE...GORSE/KRUZDLO
TIDES/COASTAL FLOODING...HEAVENER/O'HARAHAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE MOUNT HOLLY NJ 935 PM EST THU DEC 20 2012 PAZ054-055-220245- CARBON-MONROE- 935 PM EST THU DEC 20 2012 ...WINTER WEATHER ADVISORY IN EFFECT UNTIL 11 PM EST THIS EVENING... THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHEAST PENNSYLVANIA. .DAY ONE...TONIGHT. PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS. WINTER WEATHER ADVISORY. ALSO STRONG COLD FRONT WILL SWEEP ACROSS THE AREA LATE TONIGHT. A PERIOD OF MODERATE TO HEAVY RAIN IS POSSIBLE, WHICH COULD CAUSE LOCALIZED FLOODING ON ROADWAYS AND IN LOW-LYING AREAS. THERE IS ALSO THE POTENTIAL FOR WIND GUSTS TO AROUND 40 MPH ESPECIALLY WITH THE FRONT. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY. SNOW SHOWERS COULD BRING SOME ACCUMULATION LATE FRIDAY AND SATURDAY. IN ADDITION, GUSTY NORTHWESTERLY WINDS ARE EXPECTED FRIDAY AND SATURDAY, HOWEVER THE STRONGER WINDS WITH GUSTS TO AROUND 45 MPH LOOK TO OCCUR ON SATURDAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. NJZ001-008-010-220245- SUSSEX-MORRIS-SOMERSET- 935 PM EST THU DEC 20 2012 ...WIND ADVISORY IN EFFECT FROM 2 AM TO 9 AM EST FRIDAY... THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHERN NEW JERSEY. .DAY ONE...TONIGHT. PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS. WIND ADVISORY. A STRONG COLD FRONT WILL SWEEP ACROSS THE AREA LATE TONIGHT. A PERIOD OF MODERATE TO HEAVY RAIN IS POSSIBLE, WHICH COULD CAUSE LOCALIZED FLOODING ON ROADWAYS AND IN LOW-LYING AREAS. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY. PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS. WIND ADVISORY. GUSTY NORTHWESTERLY WINDS ARE EXPECTED FRIDAY AND SATURDAY, HOWEVER THE STRONGER WINDS WITH GUSTS BETWEEN 40 AND 50 MPH LOOK TO OCCUR ON SATURDAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. NJZ007-009-015-PAZ060>062-101>106-220245- WARREN-HUNTERDON-MERCER-BERKS-LEHIGH-NORTHAMPTON-WESTERN CHESTER- EASTERN CHESTER-WESTERN MONTGOMERY-EASTERN MONTGOMERY-UPPER BUCKS- LOWER BUCKS- 935 PM EST THU DEC 20 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL NEW JERSEY...NORTHERN NEW JERSEY...NORTHWEST NEW JERSEY...EAST CENTRAL PENNSYLVANIA AND SOUTHEAST PENNSYLVANIA. .DAY ONE...TONIGHT. A STRONG COLD FRONT WILL SWEEP ACROSS THE AREA LATE TONIGHT. A PERIOD OF MODERATE TO HEAVY RAIN IS POSSIBLE, WHICH COULD CAUSE LOCALIZED FLOODING ON ROADWAYS AND IN LOW-LYING AREAS. THERE IS ALSO THE POTENTIAL FOR WIND GUSTS TO AROUND 40 MPH ESPECIALLY WITH THE FRONT. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY. GUSTY NORTHWESTERLY WINDS ARE EXPECTED FRIDAY AND SATURDAY, HOWEVER THE STRONGER WINDS WITH GUSTS BETWEEN 40 AND 50 MPH LOOK TO OCCUR ON SATURDAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. NJZ012>014-020-022-025>027-220245- MIDDLESEX-WESTERN MONMOUTH-EASTERN MONMOUTH-OCEAN-ATLANTIC- COASTAL ATLANTIC-COASTAL OCEAN-SOUTHEASTERN BURLINGTON- 935 PM EST THU DEC 20 2012 ...COASTAL FLOOD ADVISORY IN EFFECT UNTIL 8 AM EST FRIDAY... ...WIND ADVISORY IN EFFECT FROM 2 AM TO 9 AM EST FRIDAY... THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL NEW JERSEY...NORTHERN NEW JERSEY AND SOUTHERN NEW JERSEY. .DAY ONE...TONIGHT. PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS. COASTAL FLOOD ADVISORY. WIND ADVISORY. A STRONG COLD FRONT WILL SWEEP ACROSS THE AREA LATE TONIGHT. A PERIOD OF MODERATE TO HEAVY RAIN IS POSSIBLE, WHICH COULD CAUSE LOCALIZED FLOODING ON ROADWAYS AND IN LOW-LYING AREAS. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY. PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS. COASTAL FLOOD ADVISORY. WIND ADVISORY. GUSTY NORTHWESTERLY WINDS ARE EXPECTED FRIDAY AND SATURDAY, HOWEVER THE STRONGER WINDS WITH GUSTS BETWEEN 40 AND 50 MPH LOOK TO OCCUR ON SATURDAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. NJZ017>019-PAZ070-071-220245- GLOUCESTER-CAMDEN-NORTHWESTERN BURLINGTON-DELAWARE-PHILADELPHIA- 935 PM EST THU DEC 20 2012 ...COASTAL FLOOD ADVISORY IN EFFECT FROM 3 AM TO 11 AM EST FRIDAY... THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHERN NEW JERSEY AND SOUTHEAST PENNSYLVANIA. .DAY ONE...TONIGHT. PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS. COASTAL FLOOD ADVISORY. A STRONG COLD FRONT WILL SWEEP ACROSS THE AREA LATE TONIGHT. A PERIOD OF MODERATE TO HEAVY RAIN IS POSSIBLE, WHICH COULD CAUSE LOCALIZED FLOODING ON ROADWAYS AND IN LOW-LYING AREAS. THERE IS ALSO THE POTENTIAL FOR WIND GUSTS UP TO 45 MPH ESPECIALLY WITH THE FRONT. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY. PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS. COASTAL FLOOD ADVISORY. GUSTY NORTHWESTERLY WINDS ARE EXPECTED FRIDAY AND SATURDAY, HOWEVER THE STRONGER WINDS WITH GUSTS BETWEEN 40 AND 50 MPH LOOK TO OCCUR ON SATURDAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. ANZ430-431-450>455-220245- DELAWARE BAY WATERS NORTH OF EAST POINT NJ TO SLAUGHTER BEACH DE- DELAWARE BAY WATERS SOUTH OF EAST POINT NJ TO SLAUGHTER BEACH DE- COASTAL WATERS FROM SANDY HOOK TO MANASQUAN INLET NJ OUT 20 NM- COASTAL WATERS FROM MANASQUAN INLET TO LITTLE EGG INLET NJ OUT 20 NM- COASTAL WATERS FROM LITTLE EGG INLET TO GREAT EGG INLET NJ OUT 20 NM- COASTAL WATERS FROM GREAT EGG INLET TO CAPE MAY NJ OUT 20 NM- COASTAL WATERS FROM CAPE MAY NJ TO CAPE HENLOPEN DE OUT 20 NM- COASTAL WATERS FROM CAPE HENLOPEN TO FENWICK ISLAND DE OUT 20 NM- 935 PM EST THU DEC 20 2012 ...GALE WARNING IN EFFECT UNTIL 7 PM EST SATURDAY... THIS HAZARDOUS WEATHER OUTLOOK IS FOR ATLANTIC COASTAL WATERS AND DELAWARE BAY WATERS. .DAY ONE...TONIGHT. PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS. GALE WARNING. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY. PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS. GALE WARNING. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. DEZ003-004-NJZ023-024-220245- INLAND SUSSEX-DELAWARE BEACHES-CAPE MAY-ATLANTIC COASTAL CAPE MAY- 935 PM EST THU DEC 20 2012 ...COASTAL FLOOD ADVISORY IN EFFECT UNTIL 8 AM EST FRIDAY... ...WIND ADVISORY IN EFFECT FROM 2 AM TO 9 AM EST FRIDAY... THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHERN DELAWARE AND SOUTHERN NEW JERSEY. .DAY ONE...TONIGHT. PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS. COASTAL FLOOD ADVISORY. WIND ADVISORY. A STRONG COLD FRONT WILL SWEEP ACROSS THE AREA LATE TONIGHT. A PERIOD OF MODERATE TO HEAVY RAIN IS POSSIBLE, WHICH COULD CAUSE LOCALIZED FLOODING ON ROADWAYS AND IN LOW-LYING AREAS. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY. PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS. COASTAL FLOOD ADVISORY. WIND ADVISORY. GUSTY NORTHWESTERLY WINDS ARE EXPECTED FRIDAY AND SATURDAY, HOWEVER THE STRONGER WINDS WITH GUSTS BETWEEN 40 AND 50 MPH LOOK TO OCCUR ON SATURDAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. MDZ015-019-020-220245- QUEEN ANNES-TALBOT-CAROLINE- 935 PM EST THU DEC 20 2012 ...WIND ADVISORY IN EFFECT FROM 2 AM TO 9 AM EST FRIDAY... THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHEAST MARYLAND. .DAY ONE...TONIGHT. PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS. WIND ADVISORY. A STRONG COLD FRONT WILL SWEEP ACROSS THE AREA LATE TONIGHT. A PERIOD OF MODERATE TO HEAVY RAIN IS POSSIBLE, WHICH COULD CAUSE LOCALIZED FLOODING ON ROADWAYS AND IN LOW-LYING AREAS. THERE IS ALSO THE POTENTIAL FOR WIND GUSTS UP TO 45 MPH ESPECIALLY WITH THE FRONT. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY. PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS. WIND ADVISORY. GUSTY NORTHWESTERLY WINDS ARE EXPECTED FRIDAY AND SATURDAY, HOWEVER THE STRONGER WINDS WITH GUSTS BETWEEN 40 AND 50 MPH LOOK TO OCCUR ON SATURDAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. DEZ001-002-NJZ016-021-220245- NEW CASTLE-KENT-SALEM-CUMBERLAND- 935 PM EST THU DEC 20 2012 ...WIND ADVISORY IN EFFECT FROM 2 AM TO 9 AM EST FRIDAY... ...COASTAL FLOOD ADVISORY IN EFFECT FROM 3 AM TO 11 AM EST FRIDAY... THIS HAZARDOUS WEATHER OUTLOOK IS FOR CENTRAL DELAWARE...NORTHERN DELAWARE AND SOUTHERN NEW JERSEY. .DAY ONE...TONIGHT. PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS. WIND ADVISORY. COASTAL FLOOD ADVISORY. A STRONG COLD FRONT WILL SWEEP ACROSS THE AREA LATE TONIGHT. A PERIOD OF MODERATE TO HEAVY RAIN IS POSSIBLE, WHICH COULD CAUSE LOCALIZED FLOODING ON ROADWAYS AND IN LOW-LYING AREAS. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY. PLEASE LISTEN TO NOAA WEATHER RADIO OR GO TO WEATHER.GOV ON THE INTERNET FOR MORE INFORMATION ABOUT THE FOLLOWING HAZARDS. WIND ADVISORY. COASTAL FLOOD ADVISORY. GUSTY NORTHWESTERLY WINDS ARE EXPECTED FRIDAY AND SATURDAY, HOWEVER THE STRONGER WINDS WITH GUSTS BETWEEN 40 AND 50 MPH LOOK TO OCCUR ON SATURDAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. MDZ008-012-220245- CECIL-KENT MD- 935 PM EST THU DEC 20 2012 THIS HAZARDOUS WEATHER OUTLOOK IS FOR NORTHEAST MARYLAND. .DAY ONE...TONIGHT. A STRONG COLD FRONT WILL SWEEP ACROSS THE AREA LATE TONIGHT. A PERIOD OF MODERATE TO HEAVY RAIN IS POSSIBLE, WHICH COULD CAUSE LOCALIZED FLOODING ON ROADWAYS AND IN LOW-LYING AREAS. THERE IS ALSO THE POTENTIAL FOR WIND GUSTS UP TO 45 MPH ESPECIALLY WITH THE FRONT. .DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY. GUSTY NORTHWESTERLY WINDS ARE EXPECTED FRIDAY AND SATURDAY, HOWEVER THE STRONGER WINDS WITH GUSTS BETWEEN 40 AND 50 MPH LOOK TO OCCUR ON SATURDAY. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME.
The national radar mosaic for the moment the first event began.
3 strong wind, 1 high wind, 1 coastal flood, 1 flood. Local standard time, as filed.
The heavy rain caused considerable flooding within Wilmington as well as in New Castle. In both locations, vehicles were stuck in high water and firefighters rescued stranded motorists. In Wilmington, the Southbridge area was impacted by the flooding the hardest. South Market Street (along the Christina River), South Herald Street, New Castle Avenue, South Walnut Street (along the Chrsitina River) were totally impassable. Elsewhere in the city, East 12th Street and Interstate 495 were also flooded. Most of the flooding was gone by the middle of the morning on the 21st.
The Christina River at Coochs Bridge had moderate flooding and was above its 10.5 foot flood stage from 535 a.m. EST through 1136 a.m. EST on the 21st. It crested at 11.99 feet at 9 a.m. EST. The Red Clay Creek at Wooddale was above its 7 foot flood stage from 808 a.m. EST through 945 a.m. EST on the 21st. It crested at 7.11 feet at 845 a.m. EST. The Red Clay Creek at Stanton was above its 15 foot flood stage from 853 a.m. EST through 1217 p.m. EST on the 21st. It crested at 15.19 feet at 945 a.m. EST.
Event precipitation totals included 2.45 inches in Newark, 1.64 inches in Newport, 1.44 inches at the Wilmington Airport and 1.43 inches in Middletown.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Delaware in 2012Every state in 2012This day in weather historyWarnings in Delaware, December 2012
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 426461, 426462, 426463, 426460, 425751, 425749.