Alert archive / Pennsylvania / Winter Storm Watches in 2007

Winter Storm Watch 6, NWS Philadelphia/Mount Holly

December 12, 20075 counties in Pennsylvania; Morris County, Sussex County, Warren County, New Jersey

NWS Philadelphia/Mount Holly issued this winter storm watch at Dec 12, 2007, 3:51 AM EST for 5 counties in Pennsylvania; Morris County, Sussex County, Warren County, New Jersey. It took effect at Dec 13, 2007, 10:00 AM EST. It was in force for .

The area

The counties it named.

The facts

Issued
Dec 12, 2007, 3:51 AM EST (08:51 UTC)
In effect from
Dec 13, 2007, 10:00 AM EST
Expired
Dec 12, 2007, 4:25 PM EST
In force
Issued by
NWS Philadelphia/Mount Holly

Counties Morris County, NJ, Sussex County, NJ, Warren County, NJ, Berks County, PA, Carbon County, PA, Lehigh County, PA, Monroe County, PA, Northampton County, PA

The radar

The Philadelphia radar (KDIX), 122 km from the middle of the area, began a volume at 08:53 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Brookhaven, NY (KOKX), launched 00:00Z, 8.9 hours before the alert went out and 202 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Brookhaven, NY at 00:00Z on 2007-12-12Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Brookhaven, NY at 00:00Z on 2007-12-12The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 554 square meters per square second.1939587897117Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
620 m above ground
0-6 km bulk shear
78 kt
0-1 km storm-relative helicity
554 m²/s²
0-3 km storm-relative helicity
805 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
WWUS41 KPHI 120851
WSWPHI

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
351 AM EST WED DEC 12 2007

NJZ001-007-008-PAZ054-055-060>062-122200-
/O.NEW.KPHI.WS.A.0006.071213T1500Z-071214T0600Z/
SUSSEX-WARREN-MORRIS-CARBON-MONROE-BERKS-LEHIGH-NORTHAMPTON-
INCLUDING THE CITIES OF...NEWTON...WASHINGTON...MORRISTOWN...
JIM THORPE...STROUDSBURG...READING...ALLENTOWN...BETHLEHEM...
EASTON
351 AM EST WED DEC 12 2007

...WINTER STORM WATCH IN EFFECT FROM THURSDAY MORNING THROUGH
LATE THURSDAY NIGHT...

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY HAS ISSUED A WINTER
STORM WATCH...WHICH IS IN EFFECT FROM THURSDAY MORNING THROUGH
LATE THURSDAY NIGHT. 

AN AREA OF LOW PRESSURE WILL MOVE EASTWARD FROM THE OHIO VALLEY
AND CROSS THE REGION THURSDAY INTO THURSDAY NIGHT BEFORE MOVING
OUT TO SEA.  

LOW TEMPERATURES THURSDAY MORNING WILL BE AT OR BELOW FREEZING
ACROSS THE WATCH AREA. TEMPERATURES WILL STRUGGLE TO REACH THE
FREEZING MARK DURING THE DAY ON THURSDAY. AS A RESULT, ANY
PRECIPITATION THAT FALLS WILL PREDOMINANTLY BE IN THE FORM OF
SNOW, WITH SOME SLEET OR FREEZING RAIN MIXING IN OVER THE WATCH AREA.

THERE IS STILL SOME UNCERTAINTY AS TO THE EXACT TRACK AND SPEED OF
THIS SYSTEM. HOWEVER, THE SYSTEM IS FORECAST TO MOVE RELATIVELY
QUICKLY. SNOWFALL ACCUMULATIONS OF UP TO 6 INCHES ARE POSSIBLE ACROSS
THE WATCH AREA BY THURSDAY NIGHT. NEVERTHELESS, IT IS IMPORTANT TO
NOTE THAT A SLIGHTLY FASTER OR SLOWER SPEED OR A CHANGE IN
TEMPERATURE BY EVEN 1 OR 2 DEGREES CAN GREATLY AFFECT ACCUMULATIONS.
IF THE STORM MOVES FASTER, THEN LESS PRECIPITATION WILL FALL. IF
TEMPS ARE WARMER, THERE COULD BE MORE SLEET OR FREEZING RAIN,
WHICH, WHILE KEEPING SNOW ACCUMULATIONS DOWN, PRESENT PROBLEMS OF
THEIR OWN.

RIGHT NOW, IT APPEARS THAT THE PRECIPITATION WILL HOLD OFF UNTIL
AFTER MORNING RUSH HOUR ON THURSDAY. HOWEVER, THE STORM WILL BE
BEARING DOWN ON THE WATCH AREA BY THURSDAY AFTERNOON.

A WINTER STORM WATCH MEANS THERE IS A POTENTIAL FOR SIGNIFICANT
SNOW...SLEET...OR ICE ACCUMULATIONS THAT MAY IMPACT TRAVEL.
CONTINUE TO MONITOR THE LATEST FORECASTS AND LISTEN TO NOAA
WEATHER RADIO OR YOUR FAVORITE MEDIA OUTLET FOR FURTHER UPDATES.

$$

NIERENBERG
1 follow-up statement
000 
WWUS41 KPHI 122125
WSWPHI

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
425 PM EST WED DEC 12 2007

...A WINTER STORM TO AFFECT THE REGION DURING THURSDAY...

.AN AREA OF LOW PRESSURE WILL ORGANIZE ACROSS THE SOUTHERN 
PLAINS AND MOVE INTO THE OHIO VALLEY TONIGHT. THIS STORM WILL THEN 
MOVE ACROSS OUR REGION DURING THURSDAY, BRINGING WITH IT A ROUND OF 
WINTRY PRECIPITATION. THIS STORM IS EXPECTED TO BRING A SIGNIFICANT 
AMOUNT OF SNOW AND EVEN SLEET TO A GOOD PORTION OF EASTERN PENNSYLVANIA
AND INTO NORTHWESTERN NEW JERSEY, WITH LESSER AMOUNTS FARTHER TO
THE SOUTH AND EAST. THE STORM WILL THEN COME TO AN END DURING
THURSDAY EVENING.

NJZ001-PAZ054-055-131000-
/O.UPG.KPHI.WS.A.0006.071213T1500Z-071214T0600Z/
/O.NEW.KPHI.WS.W.0005.071213T1400Z-071214T0400Z/
SUSSEX-CARBON-MONROE-
INCLUDING THE CITIES OF...NEWTON...JIM THORPE...STROUDSBURG
425 PM EST WED DEC 12 2007

...WINTER STORM WARNING IN EFFECT FROM 9 AM TO 11 PM EST
THURSDAY...
...WINTER STORM WATCH NO LONGER IN EFFECT...

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY HAS ISSUED A WINTER
STORM WARNING, WHICH IS IN EFFECT FROM 9 AM TO 11 PM EST THURSDAY.
THE WINTER STORM WATCH IS NO LONGER IN EFFECT.

SNOW IS EXPECTED TO OVERSPREAD THE AREA THURSDAY MORNING AND INCREASE 
IN INTENSITY AROUND MIDDAY THEN CONTINUE THROUGH THE AFTERNOON
WITH SOME SLEET POSSIBLY MIXING IN. SNOWFALL RATES OF AN INCH PER
HOUR WILL BE POSSIBLE MAINLY DURING THE AFTERNOON. A TOTAL SNOW
ACCUMULATION OF 6 TO 10 INCHES ARE ANTICIPATED, WHICH WILL MAKE
TRAVEL VERY HAZARDOUS. THE STEADIEST PRECIPITATION WILL BE
TAPERING OFF DURING THURSDAY EVENING.

A WINTER STORM WARNING MEANS SIGNIFICANT AMOUNTS OF SNOW AND SLEET
ARE EXPECTED OR OCCURRING. THIS WILL MAKE TRAVEL VERY HAZARDOUS
OR IMPOSSIBLE.

ANOTHER WINTER STORM MAY AFFECT THE AREA THIS WEEKEND. STAY TUNED
TO NOAA WEATHER RADIO ALL HAZARDS OR YOUR LOCAL MEDIA OUTLETS FOR
FURTHER UPDATES.

$$

NJZ007-008-PAZ060>062-131000-
/O.UPG.KPHI.WS.A.0006.071213T1500Z-071214T0600Z/
/O.NEW.KPHI.WS.W.0005.071213T1400Z-071214T0400Z/
WARREN-MORRIS-BERKS-LEHIGH-NORTHAMPTON-
INCLUDING THE CITIES OF...WASHINGTON...MORRISTOWN...READING...
ALLENTOWN...BETHLEHEM...EASTON
425 PM EST WED DEC 12 2007

...WINTER STORM WARNING IN EFFECT FROM 9 AM TO 11 PM EST
THURSDAY...
...WINTER STORM WATCH NO LONGER IN EFFECT...

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY HAS ISSUED A WINTER
STORM WARNING, WHICH IS IN EFFECT FROM 9 AM TO 11 PM EST THURSDAY.
THE WINTER STORM WATCH IS NO LONGER IN EFFECT.

A MIXTURE OF SNOW AND SLEET WILL OVERSPREAD THE REGION THURSDAY 
EVENING AND INCREASE IN INTENSITY AROUND MIDDAY AND CONTINUE THROUGH 
THE AFTERNOON. A TOTAL ACCUMULATION OF SNOW AND SLEET OF 5 TO AS
MUCH AS 8 INCHES ARE ANTICIPATED, MAKING TRAVEL HAZARDOUS. THERE
IS THE POSSIBILITY THAT A BIT OF FREEZING RAIN MAY MIX IN AT
TIMES DURING THE AFTERNOON, HOWEVER SNOW AND SLEET ARE THE
ANTICIPATED PREDOMINANT PRECIPITATION TYPES. THE STEADIEST
PRECIPITATION WILL BE TAPERING OFF DURING THURSDAY EVENING.

A WINTER STORM WARNING MEANS SIGNIFICANT AMOUNTS OF SNOW, SLEET, AND
ICE ARE EXPECTED OR OCCURRING. THIS WILL MAKE TRAVEL VERY HAZARDOUS.

ANOTHER WINTER STORM MAY AFFECT THE AREA THIS WEEKEND. STAY TUNED
TO NOAA WEATHER RADIO ALL HAZARDS OR YOUR LOCAL MEDIA OUTLETS FOR
FURTHER UPDATES.

$$

MDZ008-NJZ009-010-012-015-PAZ067>069-131000-
/O.NEW.KPHI.WW.Y.0016.071213T1400Z-071214T0400Z/
CECIL-HUNTERDON-SOMERSET-MIDDLESEX-MERCER-CHESTER-MONTGOMERY-
BUCKS-
INCLUDING THE CITIES OF...ELKTON...FLEMINGTON...SOMERVILLE...
NEW BRUNSWICK...TRENTON...WEST CHESTER...NORRISTOWN...DOYLESTOWN
425 PM EST WED DEC 12 2007

...WINTER WEATHER ADVISORY IN EFFECT FROM 9 AM TO 11 PM EST
THURSDAY...

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY HAS ISSUED A WINTER
WEATHER ADVISORY, WHICH IS IN EFFECT FROM 9 AM TO 11 PM EST
THURSDAY.

A WINTRY MIX OF SNOW, SLEET AND FREEZING RAIN WILL OVERSPREAD THE 
REGION THURSDAY MORNING. AS MILDER AIR MOVES IN, LOCATIONS FARTHER 
SOUTH AND EAST WILL BEGIN TO CHANGE OVER TO PLAIN RAIN DURING 
THURSDAY AFTERNOON LIMITING ACCUMULATIONS, HOWEVER SLEET CAN STILL
MIX IN. FOR LOCATIONS FARTHER NORTH AND WEST, A MORE PROLONGED
PERIOD OF SLEET MIXED WITH FREEZING RAIN IS ANTICIPATED. A TOTAL
ACCUMULATION OF SNOW AND SLEET RANGING FROM 2 TO AS MUCH AS 5
INCHES ARE ANTICIPATED ACROSS THE AREA, WITH THE HIGHEST AMOUNTS
FOCUSED ACROSS THE NORTHERN AND WESTERN PORTIONS OF THE AFFECTED
COUNTIES. ICE ACCUMULATIONS OF A TENTH OF AN INCH OR LESS ARE 
EXPECTED. THE STEADIEST PRECIPITATION WILL BE TAPERING OFF DURING
THURSDAY EVENING.

A WINTER WEATHER ADVISORY MEANS THAT PERIODS OF SNOW, SLEET, OR
FREEZING RAIN WILL CAUSE TRAVEL DIFFICULTIES. BE PREPARED FOR
SLIPPERY ROADS AND LIMITED VISIBILITIES, AND USE CAUTION WHILE
DRIVING.

ANOTHER WINTER STORM MAY AFFECT THE AREA THIS WEEKEND. STAY TUNED
TO NOAA WEATHER RADIO ALL HAZARDS OR YOUR LOCAL MEDIA OUTLETS FOR
FURTHER UPDATES.

$$

GORSE

The office that day

Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Dec 12, 4:25 PM ESTWinter Storm WarningPHIBerks, Carbon, Lehigh, Monroe, Northampton27 hr
Dec 12, 4:25 PM ESTWinter Weather AdvisoryPHI22 hr

Nearby

Winter Storm Watches in Pennsylvania, 2007Winter Storm Watches in New Jersey, 2007Every winter storm watch in 2007

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.