Alert archive / Pennsylvania / Frost Advisories in 2007

Frost Advisory 8, NWS Philadelphia/Mount Holly

October 29, 2007Delaware County, Philadelphia County, Pennsylvania; New Castle County, Delaware

NWS Philadelphia/Mount Holly issued this frost advisory at Oct 29, 2007, 3:20 PM EDT for Delaware County, Philadelphia County, Pennsylvania; New Castle County, Delaware. It took effect at Oct 30, 2007, 3:00 AM EDT. It was in force for 5 hr.

The area

The counties it named.

The facts

Issued
Oct 29, 2007, 3:20 PM EDT (19:20 UTC)
In effect from
Oct 30, 2007, 3:00 AM EDT
Expired
Oct 30, 2007, 8:00 AM EDT
In force
5 hr
Issued by
NWS Philadelphia/Mount Holly

Counties New Castle County, DE, Delaware County, PA, Philadelphia County, PA

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 7.3 hours before the alert went out and 199 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, Washington/Dulle, VA at 12:00Z on 2007-10-29Temperature 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, Washington/Dulle, VA at 12:00Z on 2007-10-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -18 square meters per square second.19395878Sfc1 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
1247 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
-18 m²/s²
0-3 km storm-relative helicity
49 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 
WWUS71 KPHI 291920
NPWPHI

URGENT - WEATHER MESSAGE
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
320 PM EDT MON OCT 29 2007

DEZ002-003-MDZ012-015-019-020-301200-
/O.NEW.KPHI.FZ.W.0005.071030T0700Z-071030T1200Z/
KENT DE-INLAND SUSSEX-KENT MD-QUEEN ANNES-TALBOT-CAROLINE-
INCLUDING THE CITIES OF...DOVER...GEORGETOWN...CHESTERTOWN...
CENTREVILLE...EASTON...DENTON
320 PM EDT MON OCT 29 2007

...FREEZE WARNING IN EFFECT FROM 3 AM TO 8 AM EDT TUESDAY...

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY HAS ISSUED A FREEZE
WARNING, WHICH IS IN EFFECT FROM 3 AM TO 8 AM EDT TUESDAY.

CLEAR SKIES AND CALM WINDS OVERNIGHT WILL LEAD TO A PERIOD OF 
SUB-FREEZING TEMPERATURES AND WIDESPREAD FROST OVER MUCH OF
CENTRAL AND SOUTHERN DELAWARE AND ADJACENT PORTIONS OF THE
MARYLAND EASTERN SHORE. THESE CONDITIONS WILL KILL SENSITIVE
VEGETATION. 

IF YOU HAVE ANY SENSITIVE PLANTS OUTSIDE, PROTECT THEM OR BRING
THEM INDOORS.

$$

DEZ001-PAZ070-071-301200-
/O.NEW.KPHI.FR.Y.0008.071030T0700Z-071030T1200Z/
NEW CASTLE-DELAWARE-PHILADELPHIA-
INCLUDING THE CITIES OF...WILMINGTON...MEDIA
320 PM EDT MON OCT 29 2007

...FROST ADVISORY IN EFFECT FROM 3 AM TO 8 AM EDT TUESDAY...

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY HAS ISSUED A FROST
ADVISORY, WHICH IS IN EFFECT FROM 3 AM TO 8 AM EDT TUESDAY.

CLEAR SKIES AND CALM WINDS OVERNIGHT WILL LEAD TO ANOTHER COLD
NIGHT. AREAS OF FROST ARE FORECAST OUTSIDE OF CENTER CITY
PHILADELPHIA. SENSITIVE OUTDOOR PLANTS MAY BE KILLED IF LEFT
UNCOVERED.

IF YOU HAVE ANY SENSITIVE PLANTS OUTSIDE, PROTECT THEM OR BRING
THEM INDOORS. 

$$

MPD
1 follow-up statement
000 
WWUS71 KPHI 301223
NPWPHI

URGENT - WEATHER MESSAGE
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
823 AM EDT TUE OCT 30 2007

...FREEZE WARNING NO LONGER IN EFFECT...

THE FREEZE WARNING IS NO LONGER IN EFFECT. THERE WERE SOME
ISOLATED AREAS OF NORTHWEST NEW JERSEY WHERE THE TEMPERATURE WAS
AT 31 DEGREES BUT WILL SOON CLIMB INTO THE MID 30S SHORTLY. 

DEZ002-003-MDZ012-015-019-020-301330-
/O.EXP.KPHI.FZ.W.0005.000000T0000Z-071030T1200Z/
KENT DE-INLAND SUSSEX-KENT MD-QUEEN ANNES-TALBOT-CAROLINE-
INCLUDING THE CITIES OF...DOVER...GEORGETOWN...CHESTERTOWN...
CENTREVILLE...EASTON...DENTON
823 AM EDT TUE OCT 30 2007

...FREEZE WARNING HAS EXPIRED...

THE FREEZE WARNING IS NO LONGER IN EFFECT. 

TEMPERATURES ACROSS THE REGION HAVE CLIMBED ABOVE THE FREEZING
MARK.

$$

DEZ001-PAZ070-071-301330-
/O.EXP.KPHI.FR.Y.0008.000000T0000Z-071030T1200Z/
NEW CASTLE-DELAWARE-PHILADELPHIA-
INCLUDING THE CITIES OF...WILMINGTON...MEDIA
823 AM EDT TUE OCT 30 2007

...FROST ADVISORY HAS EXPIRED...

THE FROST ADVISORY IS NO LONGER IN EFFECT. 

THE TEMPERATURES HAVE CLIMBED INTO THE LOWER 40S THIS HOUR. 

$$

EBERWINE

The office that day

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

IssuedProductOfficeCountiesLasted
Oct 29, 3:20 PM EDTFreeze WarningPHIKent, Sussex17 hr

Nearby

Frost Advisories in Pennsylvania, 2007Frost Advisories in Delaware, 2007Every frost 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.