Alert archive / New Jersey / Freeze Warnings in 2020

Freeze Warning 2, NWS Philadelphia/Mount Holly

April 16, 20204 states

NWS Philadelphia/Mount Holly issued this freeze warning at Apr 16, 2020, 3:19 PM EDT for 4 states. It took effect at Apr 17, 2020, 12:00 AM EDT. It was in force for 9 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Apr 16, 2020, 3:19 PM EDT (19:19 UTC)
In effect from
Apr 17, 2020, 12:00 AM EDT
Expired
Apr 17, 2020, 9:00 AM EDT
In force
9 hr
Issued by
NWS Philadelphia/Mount Holly
All 29 counties

Kent 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, Burlington County, NJ, Camden County, NJ, Cape May County, NJ, Cumberland County, NJ, Gloucester County, NJ, Hunterdon County, NJ, Mercer County, NJ, Middlesex County, NJ, Monmouth County, NJ, Morris County, NJ, Ocean County, NJ, Salem County, NJ, Somerset County, NJ, Sussex County, NJ, Warren County, NJ, Berks County, PA, Bucks County, PA, Chester County, PA, Lehigh County, PA, Montgomery County, PA, Northampton County, PA

The radar

The Philadelphia radar (KDIX), 65 km from the middle of the area, began a volume at 19:19 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

Washington/Dulle, VA (KIAD), launched 12:00Z, 7.3 hours before the alert went out and 219 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 2020-04-16Temperature 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 2020-04-16The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -49 square meters per square second.1939587897117136156Sfc1 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
1627 m above ground
0-6 km bulk shear
80 kt
0-1 km storm-relative helicity
-49 m²/s²
0-3 km storm-relative helicity
42 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

906 
WWUS71 KPHI 161919
NPWPHI

URGENT - WEATHER MESSAGE
National Weather Service Mount Holly NJ
319 PM EDT Thu Apr 16 2020

DEZ002-003-MDZ008-012-015-019-020-NJZ001-007>010-012-013-015-
019>022-027-PAZ060>062-101>103-105-170830-
/O.UPG.KPHI.FZ.A.0002.200417T0400Z-200417T1300Z/
/O.NEW.KPHI.FZ.W.0002.200417T0400Z-200417T1300Z/
Kent-Inland Sussex-Cecil-Kent MD-Queen Annes-Talbot-Caroline-
Sussex-Warren-Morris-Hunterdon-Somerset-Middlesex-
Western Monmouth-Mercer-Northwestern Burlington-Ocean-Cumberland-
Atlantic-Southeastern Burlington-Berks-Lehigh-Northampton-
Western Chester-Eastern Chester-Western Montgomery-Upper Bucks-
Including the cities of Dover, Georgetown, Elkton, Chestertown, 
Centreville, Easton, Denton, Newton, Washington, Morristown, 
Flemington, Somerville, New Brunswick, Freehold, Trenton, 
Moorestown, Mount Holly, Jackson, Millville, Hammonton, 
Wharton State Forest, Reading, Allentown, Bethlehem, Honey Brook,
Oxford, West Chester, Kennett Square, Collegeville, Pottstown, 
Chalfont, and Perkasie
319 PM EDT Thu Apr 16 2020

...FREEZE WARNING IN EFFECT FROM MIDNIGHT TONIGHT TO 9 AM EDT
FRIDAY...

* WHAT...Sub-freezing temperatures as low as 27 degrees expected.

* WHERE...Portions of central, northern, northwest and southern 
  New Jersey, east central and southeast Pennsylvania, northeast 
  Maryland and central and southern Delaware.

* WHEN...From midnight tonight to 9 AM EDT Friday.

* IMPACTS...Frost and freeze conditions will kill crops, other
  sensitive vegetation and possibly damage unprotected outdoor
  plumbing.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Take steps now to protect tender plants from the cold.

&&

$$

NJZ016>018-023-PAZ104-106-170830-
/O.NEW.KPHI.FZ.W.0002.200417T0400Z-200417T1300Z/
Salem-Gloucester-Camden-Cape May-Eastern Montgomery-Lower Bucks-
Including the cities of Pennsville, Glassboro, Camden, 
Cherry Hill, Cape May Court House, Norristown, Lansdale, 
Morrisville, and Doylestown
319 PM EDT Thu Apr 16 2020

...FREEZE WARNING IN EFFECT FROM MIDNIGHT TONIGHT TO 9 AM EDT
FRIDAY...

* WHAT...Sub-freezing temperatures as low as 30 expected.

* WHERE...In New Jersey, Salem, Gloucester, Camden and Cape May. 
  In Pennsylvania, Eastern Montgomery and Lower Bucks.

* WHEN...From midnight tonight to 9 AM EDT Friday.

* IMPACTS...Frost and freeze conditions will kill crops, other
  sensitive vegetation and possibly damage unprotected outdoor
  plumbing.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Take steps now to protect tender plants from the cold.

&&

$$

DEZ001-PAZ070-071-170830-
/O.NEW.KPHI.FR.Y.0002.200417T0400Z-200417T1300Z/
New Castle-Delaware-Philadelphia-
Including the cities of Wilmington, Media, and Philadelphia
319 PM EDT Thu Apr 16 2020

...FROST ADVISORY IN EFFECT FROM MIDNIGHT TONIGHT TO 9 AM EDT
FRIDAY...

* WHAT...Temperatures as low as 32 will result in frost 
  formation.

* WHERE...In Pennsylvania, Delaware and Philadelphia. In 
  Delaware, New Castle.

* WHEN...From midnight tonight to 9 AM EDT Friday.

* IMPACTS...Frost could damage or kill sensitive outdoor 
  vegetation if left uncovered.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Take steps now to protect tender plants from the cold.

&&

$$
2 follow-up statements
004 
WWUS71 KPHI 170116
NPWPHI

URGENT - WEATHER MESSAGE
National Weather Service Mount Holly NJ
916 PM EDT Thu Apr 16 2020

DEZ002-003-MDZ008-012-015-019-020-NJZ001-007>010-012-013-015>023-
027-PAZ060>062-101>106-171300-
/O.CON.KPHI.FZ.W.0002.200417T0400Z-200417T1300Z/
Kent-Inland Sussex-Cecil-Kent MD-Queen Annes-Talbot-Caroline-
Sussex-Warren-Morris-Hunterdon-Somerset-Middlesex-
Western Monmouth-Mercer-Salem-Gloucester-Camden-
Northwestern Burlington-Ocean-Cumberland-Atlantic-Cape May-
Southeastern Burlington-Berks-Lehigh-Northampton-Western Chester-
Eastern Chester-Western Montgomery-Eastern Montgomery-Upper Bucks-
Lower Bucks-
Including the cities of Dover, Georgetown, Elkton, Chestertown, 
Centreville, Easton, Denton, Newton, Washington, Morristown, 
Flemington, Somerville, New Brunswick, Freehold, Trenton, 
Pennsville, Glassboro, Camden, Cherry Hill, Moorestown, 
Mount Holly, Jackson, Millville, Hammonton, Cape May Court House,
Wharton State Forest, Reading, Allentown, Bethlehem, Honey Brook,
Oxford, West Chester, Kennett Square, Collegeville, Pottstown, 
Norristown, Lansdale, Chalfont, Perkasie, Morrisville, 
and Doylestown
916 PM EDT Thu Apr 16 2020

...FREEZE WARNING REMAINS IN EFFECT UNTIL 9 AM EDT FRIDAY...

* WHAT...Sub-freezing temperatures as low as 27 expected.

* WHERE...Portions of central, northern and southern New Jersey, 
  east central and southeast Pennsylvania, northeast Maryland and 
  central and southern Delaware.

* WHEN...Until 9 AM EDT Friday.

* IMPACTS...Frost and freeze conditions will kill crops, other 
  sensitive vegetation and possibly damage unprotected outdoor 
  plumbing.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Take steps now to protect tender plants from the cold.

&&

$$

DEZ001-PAZ070-071-171300-
/O.CON.KPHI.FR.Y.0002.200417T0400Z-200417T1300Z/
New Castle-Delaware-Philadelphia-
Including the cities of Wilmington, Media, and Philadelphia
916 PM EDT Thu Apr 16 2020

...FROST ADVISORY REMAINS IN EFFECT UNTIL 9 AM EDT FRIDAY...

* WHAT...Temperatures as low as 32 will result in frost 
  formation.

* WHERE...In Pennsylvania, Delaware and Philadelphia. In 
  Delaware, New Castle.

* WHEN...Until 9 AM EDT Friday.

* IMPACTS...Frost could kill sensitive outdoor vegetation if 
  left uncovered.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Take steps now to protect tender plants from the cold.

&&

$$
269 
WWUS71 KPHI 171245
NPWPHI

URGENT - WEATHER MESSAGE
National Weather Service Mount Holly NJ
845 AM EDT Fri Apr 17 2020

DEZ002-003-MDZ008-012-015-019-020-NJZ001-007>010-012-013-015>023-
027-PAZ060>062-101>106-171345-
/O.EXP.KPHI.FZ.W.0002.000000T0000Z-200417T1300Z/
Kent-Inland Sussex-Cecil-Kent MD-Queen Annes-Talbot-Caroline-
Sussex-Warren-Morris-Hunterdon-Somerset-Middlesex-
Western Monmouth-Mercer-Salem-Gloucester-Camden-
Northwestern Burlington-Ocean-Cumberland-Atlantic-Cape May-
Southeastern Burlington-Berks-Lehigh-Northampton-Western Chester-
Eastern Chester-Western Montgomery-Eastern Montgomery-Upper Bucks-
Lower Bucks-
Including the cities of Dover, Georgetown, Elkton, Chestertown, 
Centreville, Easton, Denton, Newton, Washington, Morristown, 
Flemington, Somerville, New Brunswick, Freehold, Trenton, 
Pennsville, Glassboro, Camden, Cherry Hill, Moorestown, 
Mount Holly, Jackson, Millville, Hammonton, Cape May Court House,
Wharton State Forest, Reading, Allentown, Bethlehem, Honey Brook,
Oxford, West Chester, Kennett Square, Collegeville, Pottstown, 
Norristown, Lansdale, Chalfont, Perkasie, Morrisville, 
and Doylestown
845 AM EDT Fri Apr 17 2020

...FREEZE WARNING WILL EXPIRE AT 9 AM EDT THIS MORNING...

Temperatures will continue to warm through today. The Freeze
Warning will be allowed to expire at 9 am.

$$

DEZ001-PAZ070-071-171345-
/O.EXP.KPHI.FR.Y.0002.000000T0000Z-200417T1300Z/
New Castle-Delaware-Philadelphia-
Including the cities of Wilmington, Media, and Philadelphia
845 AM EDT Fri Apr 17 2020

...FROST ADVISORY WILL EXPIRE AT 9 AM EDT THIS MORNING...

Temperatures will continue to warm through today. The Frost
Advisory will be allowed to expire at 9 am.

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Apr 16, 3:19 PM EDTFrost AdvisoryPHIDelaware, Philadelphia18 hr
Apr 16, 6:02 PM EDTSpecial Weather StatementPHILehigh, Monroe, Northampton43 min
Apr 16, 7:20 PM EDTSpecial Weather StatementPHIMonroe25 min

Nearby

Freeze Warnings in New Jersey, 2020Freeze Warnings in Pennsylvania, 2020Freeze Warnings in Maryland, 2020Every freeze warning in 2020

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.