Alert archive / Maryland / Snow Advisories in 2007

Snow Advisory 6, NWS Philadelphia/Mount Holly

April 6, 20074 counties in New Jersey; Kent County, New Castle County, Sussex County, Delaware; 5 counties in Maryland

NWS Philadelphia/Mount Holly issued this snow advisory at Apr 6, 2007, 3:24 PM EDT for 4 counties in New Jersey; Kent County, New Castle County, Sussex County, Delaware; 5 counties in Maryland. It took effect at Apr 6, 2007, 9:46 PM EDT. It was in force for 11 hr.

The area

The counties it named.

The facts

Issued
Apr 6, 2007, 3:24 PM EDT (19:24 UTC)
In effect from
Apr 6, 2007, 9:46 PM EDT
Expired
Apr 7, 2007, 9:00 AM EDT
In force
11 hr
Issued by
NWS Philadelphia/Mount Holly

Counties Kent County, DE, New Castle County, DE, Sussex County, DE, Caroline County, MD, Cecil County, MD, Kent County, MD, Queen Anne's County, MD, Talbot County, MD, Atlantic County, NJ, Cape May County, NJ, Cumberland County, NJ, Salem County, NJ

The radar

The Dover AFB radar (KDOX), 42 km from the middle of the area, began a volume at 19:29 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

Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 7.4 hours before the alert went out and 57 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, Phillips Aaf/Abe, MD at 12:00Z on 2007-04-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 6 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Phillips Aaf/Abe, MD at 12:00Z on 2007-04-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 4 square meters per square second.1939587897117136Sfc1 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
6 J/kg
Mixed-layer CIN
-8 J/kg
Mixed-layer LCL
1136 m above ground
0-6 km bulk shear
69 kt
0-1 km storm-relative helicity
4 m²/s²
0-3 km storm-relative helicity
27 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 061924
WSWPHI

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
324 PM EDT FRI APR 6 2007

DEZ002>004-MDZ012-015-019-020-NJZ021-023-024-071100-
/O.NEW.KPHI.SN.Y.0006.070407T0600Z-070407T1500Z/
KENT DE-INLAND SUSSEX-DELAWARE BEACHES-KENT MD-QUEEN ANNES-
TALBOT-CAROLINE-CUMBERLAND-CAPE MAY-ATLANTIC COASTAL CAPE MAY-
INCLUDING THE CITIES OF...DOVER...GEORGETOWN...REHOBOTH BEACH...
CHESTERTOWN...CENTREVILLE...EASTON...DENTON...MILLVILLE...
CAPE MAY COURT HOUSE...OCEAN CITY
324 PM EDT FRI APR 6 2007

...SNOW ADVISORY IN EFFECT FROM 2 AM TO 11 AM EDT SATURDAY...

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY HAS ISSUED A SNOW
ADVISORY...WHICH IS IN EFFECT FROM 2 AM TO 11 AM EDT SATURDAY. 

AN AREA OF LOW PRESSURE IS EXPECTED TO DEVELOP ALONG THE MID 
ATLANTIC COAST DURING THE OVERNIGHT HOURS, THEN INTENSIFY AS IT 
MOVES NORTHEAST AWAY FROM THE REGION ON SATURDAY. MOISTURE FROM THIS 
SYSTEM WILL START TO OVERSPREAD THE AREA FROM WEST TO EAST AROUND OR 
JUST AFTER MIDNIGHT, THEN MOVE OUT OF THE REGION BY LATE SATURDAY 
MORNING.

WITH COLD AIR ALREADY IN PLACE, PRECIPITATION WILL FALL IN THE FORM 
OF WET SNOW ACROSS THE ENTIRE MID ATLANTIC REGION.  THE HIGHEST 
SNOWFALL AMOUNTS FROM THIS LATE SEASON EVENT, ONE TO THREE INCHES, 
ARE EXPECTED ACROSS THE MIDDLE PORTIONS OF THE DELMARVA PENINSULA, 
INCLUDING TALBOT, CAROLINE, KENT AND QUEEN ANNES COUNTIES IN 
MARYLAND, SUSSEX AND KENT COUNTIES IN DELAWARE, AND CUMBERLAND AND 
CAPE MAY COUNTIES IN NEW JERSEY. A WINTER WEATHER ADVISORY HAS 
THEREFORE BEEN ISSUED FOR THESE COUNTIES.

ONE OR TWO INCHES ARE EXPECTED FURTHER NORTH IN CECIL COUNTY MD, NEW 
CASTLE COUNTY DE, AND SALEM COUNTY NJ. WHILE THESE SNOWFALL AMOUNTS 
WILL CAUSE SLIPPERY DRIVING CONDITIONS, THEY DO NOT CONSTITUTE 
ENOUGH DEPTH TO WARRANT AN ADVISORY AT THIS TIME. AN INCH OR LESS IS 
EXPECTED IN AND AROUND PHILADELPHIA.    

GIVEN THAT PRECIPITATION WILL BEGIN DURING THE OVERNIGHT HOURS, SNOW 
IS EXPECTED TO STICK ON ROADWAYS AND CONCRETE SURFACES, AS WELL AS 
ON GRASSY AREAS, FROM THE ONSET. 

A SNOW ADVISORY MEANS THAT PERIODS OF SNOW WILL CAUSE PRIMARILY
TRAVEL DIFFICULTIES. BE PREPARED FOR SNOW COVERED ROADS AND
LIMITED VISIBILITIES...AND USE CAUTION WHILE DRIVING.

$$

JJM
3 follow-up statements
000 
WWUS41 KPHI 070146
WSWPHI

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
946 PM EDT FRI APR 6 2007

DEZ001-MDZ008-NJZ016-022-025-071000-
/O.EXB.KPHI.SN.Y.0006.070407T0700Z-070407T1500Z/
NEW CASTLE-CECIL-SALEM-ATLANTIC-COASTAL ATLANTIC-
INCLUDING THE CITIES OF...WILMINGTON...ELKTON...PENNSVILLE...
HAMMONTON...ATLANTIC CITY
946 PM EDT FRI APR 6 2007

...SNOW ADVISORY IN EFFECT FROM 3 AM TO 11 AM EDT SATURDAY...

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY HAS ISSUED A SNOW
ADVISORY...WHICH IS IN EFFECT FROM 3 AM TO 11 AM EDT SATURDAY. 

AN AREA OF LOW PRESSURE IS EXPECTED TO DEVELOP ALONG THE MID
ATLANTIC COAST OVERNIGHT... THEN INTENSIFY AS IT MOVES NORTHEAST
AWAY FROM THE REGION ON SATURDAY. MOISTURE FROM THIS SYSTEM WILL
START TO OVERSPREAD THE AREA FROM WEST TO EAST AFTER MIDNIGHT...
THEN MOVE OUT OF THE REGION BY LATE SATURDAY MORNING.

WITH COLD AIR ALREADY IN PLACE... PRECIPITATION WILL FALL IN THE
FORM OF WET SNOW ACROSS THE ADVISORY AREA INTO MID MORNING
SATURDAY. ONE TO THREE INCHES CAN BE EXPECTED FROM THIS EVENT BY
THE TIME PRECIPITATION ENDS LATE SATURDAY MORNING OR EARLY
SATURDAY AFTERNOON. RAIN MAY MIX WITH THE SNOW LATE SATURDAY MORNING.
A WINTER WEATHER ADVISORY HAS THEREFORE BEEN ISSUED FOR THESE
AREAS.

GIVEN THAT PRECIPITATION WILL BEGIN DURING THE OVERNIGHT HOURS
WHEN TEMPERATURES ARE BELOW FREEZING...SNOW IS EXPECTED TO STICK
TO ROADWAYS AND CONCRETE SURFACES...AS WELL AS ON GRASSY AREAS.

A SNOW ADVISORY MEANS THAT PERIODS OF SNOW WILL CAUSE PRIMARILY
TRAVEL DIFFICULTIES. BE PREPARED FOR SNOW COVERED ROADS AND
LIMITED VISIBILITIES...AND USE CAUTION WHILE DRIVING.

$$

DEZ002>004-MDZ012-015-019-020-NJZ021-023-024-071000-
/O.EXT.KPHI.SN.Y.0006.070407T0700Z-070407T1500Z/
KENT DE-INLAND SUSSEX-DELAWARE BEACHES-KENT MD-QUEEN ANNES-
TALBOT-CAROLINE-CUMBERLAND-CAPE MAY-ATLANTIC COASTAL CAPE MAY-
INCLUDING THE CITIES OF...DOVER...GEORGETOWN...REHOBOTH BEACH...
CHESTERTOWN...CENTREVILLE...EASTON...DENTON...MILLVILLE...
CAPE MAY COURT HOUSE...OCEAN CITY
946 PM EDT FRI APR 6 2007

...SNOW ADVISORY NOW IN EFFECT FROM 3 AM TO 11 AM EDT SATURDAY...

THE SNOW ADVISORY IS NOW IN EFFECT FROM 3 AM TO 11 AM EDT
SATURDAY. 

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY HAS ISSUED A SNOW
ADVISORY...WHICH IS IN EFFECT FROM 3 AM TO 11 AM EDT SATURDAY. 

AN AREA OF LOW PRESSURE IS EXPECTED TO DEVELOP ALONG THE MID
ATLANTIC COAST OVERNIGHT...THEN INTENSIFY AS IT MOVES NORTHEAST
AWAY FROM THE REGION ON SATURDAY. MOISTURE FROM THIS SYSTEM WILL
START TO OVERSPREAD THE AREA FROM WEST TO EAST AFTER MIDNIGHT...
THEN MOVE OUT OF THE REGION BY LATE SATURDAY MORNING.

WITH COLD AIR ALREADY IN PLACE... PRECIPITATION WILL FALL IN THE
FORM OF WET SNOW ACROSS THE ADVISORY AREA INTO MID MORNING
SATURDAY. THE HIGHEST SNOWFALL AMOUNTS FROM THIS LATE SEASON
EVENT...TWO TO FOUR INCHES...ARE EXPECTED ACROSS THE MIDDLE
PORTIONS OF THE DELMARVA PENINSULA...INCLUDING TALBOT...
CAROLINE... KENT AND QUEEN ANNES COUNTIES IN MARYLAND...AND
SUSSEX COUNTY IN DELAWARE. ONE TO THREE INCHES OF SNOW IS EXPECTED
IN KENT COUNTY DELAWARE..AND CAPE MAY AND CUMBERLAND COUNTIES IN NEW
JERSEY. RAIN MAY MIX WITH THE SNOW LATE SATURDAY MORNING. A WINTER
WEATHER ADVISORY THEREFORE REMAINS IN EFFECT FOR THESE AREAS.

GIVEN THAT PRECIPITATION WILL BEGIN DURING THE OVERNIGHT HOURS
WHEN TEMPERATURES ARE BELOW FREEZING...SNOW IS EXPECTED TO STICK
ON ROADWAYS AND CONCRETE SURFACES...AS WELL AS ON GRASSY AREAS.

A SNOW ADVISORY MEANS THAT PERIODS OF SNOW WILL CAUSE PRIMARILY
TRAVEL DIFFICULTIES. BE PREPARED FOR SNOW COVERED ROADS AND
LIMITED VISIBILITIES...AND USE CAUTION WHILE DRIVING.



$$
000 
WWUS41 KPHI 070743
WSWPHI

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
343 AM EDT SAT APR 7 2007

DEZ001>004-MDZ008-012-015-019-020-NJZ016-021>025-071500-
/O.CON.KPHI.SN.Y.0006.000000T0000Z-070407T1500Z/
NEW CASTLE-KENT DE-INLAND SUSSEX-DELAWARE BEACHES-CECIL-KENT MD-
QUEEN ANNES-TALBOT-CAROLINE-SALEM-CUMBERLAND-ATLANTIC-CAPE MAY-
ATLANTIC COASTAL CAPE MAY-COASTAL ATLANTIC-
INCLUDING THE CITIES OF...WILMINGTON...DOVER...GEORGETOWN...
REHOBOTH BEACH...ELKTON...CHESTERTOWN...CENTREVILLE...EASTON...
DENTON...PENNSVILLE...MILLVILLE...HAMMONTON...
CAPE MAY COURT HOUSE...OCEAN CITY...ATLANTIC CITY
343 AM EDT SAT APR 7 2007

...SNOW ADVISORY REMAINS IN EFFECT UNTIL 11 AM EDT THIS MORNING...

A SNOW ADVISORY REMAINS IN EFFECT UNTIL 11 AM EDT TODAY.

AN AREA OF LOW PRESSURE WAS DEVELOPING ALONG THE NORTHERN NORTH
CAROLINA COAST EARLY THIS MORNING. THAT LOW IS EXPECTED TO
INTENSIFY TODAY AS IT MOVES NORTHEAST AND AWAY FROM THE REGION. 
MOISTURE FROM THIS SYSTEM WILL START TO OVERSPREAD THE AREA BY 
DAYBREAK...THEN MOVE OUT OF THE REGION BY NOON. 

PRECIPITATION IS FORECAST TO FALL IN THE FORM OF WET SNOW...WITH 
ONE TO FOUR INCHES OF SNOW FORECAST OVER THE ADVISORY AREA.
GEOGRAPHICALLY...THE HIGHEST AMOUNTS ARE EXPECTED OVER SOUTHERN
DELAWARE...ADJACENT PORTIONS OF THE MARYLAND EASTERN SHORE AND
EXTREME SOUTHERN NEW JERSEY. HOWEVER...FROM A PRACTICAL
PERSPECTIVE...THESE AMOUNTS ARE MOST LIKELY TO BE REALIZED ON
GRASSY SURFACES. SOMEWHAT LESSER AMOUNTS ARE EXPECTED TO STICK ON
ROADWAYS.

A SNOW ADVISORY MEANS THAT PERIODS OF SNOW WILL CAUSE PRIMARILY
TRAVEL DIFFICULTIES. BE PREPARED FOR SNOW COVERED ROADS AND
LIMITED VISIBILITIES...AND USE CAUTION WHILE DRIVING.

$$

MPD
000 
WWUS41 KPHI 071300
WSWPHI

URGENT - WINTER WEATHER MESSAGE
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
900 AM EDT SAT APR 7 2007

DEZ001>004-MDZ008-012-015-019-020-NJZ016-021>025-071400-
/O.CAN.KPHI.SN.Y.0006.000000T0000Z-070407T1500Z/
NEW CASTLE-KENT DE-INLAND SUSSEX-DELAWARE BEACHES-CECIL-KENT MD-
QUEEN ANNES-TALBOT-CAROLINE-SALEM-CUMBERLAND-ATLANTIC-CAPE MAY-
ATLANTIC COASTAL CAPE MAY-COASTAL ATLANTIC-
INCLUDING THE CITIES OF...WILMINGTON...DOVER...GEORGETOWN...
REHOBOTH BEACH...ELKTON...CHESTERTOWN...CENTREVILLE...EASTON...
DENTON...PENNSVILLE...MILLVILLE...HAMMONTON...
CAPE MAY COURT HOUSE...OCEAN CITY...ATLANTIC CITY
900 AM EDT SAT APR 7 2007

...SNOW ADVISORY IS CANCELLED...

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY HAS CANCELLED THE
SNOW ADVISORY. 

THE HEAVIEST AREA OF SNOW HAS MOVED OFF THE COAST, SO THE SNOW
ADVISORY HAS BEEN CANCELLED.

ADDITIONAL LIGHT SNOW IS POSSIBLE THROUGH THE MORNING HOURS, BUT
ACCUMULATIONS WILL BE GENERALLY AN INCH OR LESS, AND MAINLY
CONFINED TO THE GRASSY AREAS.

ALL SNOW SHOULD TAPER OFF BY AFTERNOON.

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 6, 3:47 AM EDTFreeze WatchPHIAtlantic, Burlington, Camden, Cape May, Cumberland, Gloucester and 2 more35 hr
Apr 6, 3:47 AM EDTHard Freeze WarningPHIAtlantic, Burlington, Camden, Cape May, Cumberland, Gloucester and 2 more24 hr

Nearby

Snow Advisories in Maryland, 2007Snow Advisories in New Jersey, 2007Snow Advisories in Delaware, 2007Every snow advisory 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.