Alert archive / Pennsylvania / Special Weather Statements in 2012

Special Weather Statement, NWS Philadelphia/Mount Holly

January 15, 2012Camden County, Gloucester County, New Jersey; Chester County, Delaware County, Philadelphia County, Pennsylvania

NWS Philadelphia/Mount Holly issued this special weather statement at Jan 15, 2012, 4:32 AM EST for Camden County, Gloucester County, New Jersey; Chester County, Delaware County, Philadelphia County, Pennsylvania. It was in force for 43 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jan 15, 2012, 4:32 AM EST (09:32 UTC)
Expired
Jan 15, 2012, 5:15 AM EST
In force
43 min
Issued by
NWS Philadelphia/Mount Holly

Counties Camden County, NJ, Gloucester County, NJ, Chester County, PA, Delaware County, PA, Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 61 km from the middle of the area, began a volume at 09:31 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

Wallops Is Stn, VA (KWAL), launched 00:00Z, 9.5 hours before the alert went out and 211 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, Wallops Is Stn, VA at 00:00Z on 2012-01-15Temperature 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, Wallops Is Stn, VA at 00:00Z on 2012-01-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -24 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1469 m above ground
0-6 km bulk shear
51 kt
0-1 km storm-relative helicity
-24 m²/s²
0-3 km storm-relative helicity
57 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.

762 
WWUS81 KPHI 150932
SPSPHI

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
432 AM EST SUN JAN 15 2012

NJZ017>019-027-PAZ067-068-070-071-151015-
CAMDEN NJ-CHESTER PA-DELAWARE PA-GLOUCESTER NJ-MONTGOMERY PA-
NORTHWESTERN BURLINGTON NJ-PHILADELPHIA PA-SOUTHEASTERN BURLINGTON NJ-
432 AM EST SUN JAN 15 2012

...A HEAVIER SNOW SHOWER WILL AFFECT PORTIONS OF CAMDEN...
GLOUCESTER...DELAWARE...PHILADELPHIA...CHESTER...MONTGOMERY AND 
BURLINGTON COUNTIES...

AT 428 AM EST...NATIONAL WEATHER SERVICE DOPPLER RADAR AND SURFACE 
OBSERVATIONS CONTINUED TO TRACK A HEAVIER SNOW SHOWER OVER 
PHILADELPHIA AND LOWER MONTGOMERY COUNTY...MOVING SOUTHEAST AT ABOUT 
30 MPH. 

THIS SNOW SHOWER WILL CONTINUE TO PRODUCE A QUICK BURST OF SNOW AS IT
MOVES THROUGH PORTIONS OF THE PHILADELPHIA METRO AREA. GIVEN THE 
COLD AIR IN PLACE, A QUICK COATING OF SNOW IS OCCURRING ALONG THE
PATH OF THIS HEAVIER SNOW SHOWER. USE CAUTION IF YOU ARE TRAVELING 
IN THESE AREAS AS UNTREATED ROADWAYS CAN TURN SLIPPERY AND THE 
VISIBILITY WILL QUICKLY LOWER TO NEAR ONE MILE FOR A BRIEF TIME.

LAT...LON 3971 7472 3973 7474 3962 7485 3953 7500
      3966 7520 3966 7522 3978 7543 3980 7542
      3984 7553 4006 7593 4023 7525 4003 7498
      4004 7498 3978 7461

$$

FORECASTER: GORSE

The office that day

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

IssuedProductOfficeCountiesLasted
Jan 15, 9:19 AM ESTSmall Craft AdvisoryPHI6 hr
Jan 15, 3:51 AM ESTSpecial Weather StatementPHIDelaware, Montgomery, Philadelphia54 min

Nearby

Special Weather Statements in Pennsylvania, 2012Special Weather Statements in New Jersey, 2012Every special weather statement in 2012

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.