Alert archive / Pennsylvania / Freeze Warnings in 2021
Freeze Warning 3, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this freeze warning at Apr 21, 2021, 3:26 AM EDT for 5 counties in New Jersey; 6 counties in Pennsylvania. It took effect at Apr 22, 2021, 1:00 AM EDT. It was in force for 8 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 21, 2021, 3:26 AM EDT (07:26 UTC)
- In effect from
- Apr 22, 2021, 1:00 AM EDT
- Expired
- Apr 22, 2021, 9:00 AM EDT
- In force
- 8 hr
- Issued by
- NWS Philadelphia/Mount Holly
Counties Hunterdon County, NJ, Morris 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), 94 km from the middle of the area, began a volume at 07:30 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, 7.4 hours before the alert went out and 197 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.
- Mixed-layer CAPE
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 1938 m above ground
- 0-6 km bulk shear
- 39 kt
- 0-1 km storm-relative helicity
- 152 m²/s²
- 0-3 km storm-relative helicity
- 161 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
031 WWUS71 KPHI 210726 NPWPHI URGENT - WEATHER MESSAGE National Weather Service Mount Holly NJ 326 AM EDT Wed Apr 21 2021 NJZ001-007>010-PAZ060>062-103-105-212100- /O.UPG.KPHI.FZ.A.0002.210422T0600Z-210422T1300Z/ /O.NEW.KPHI.FZ.W.0003.210422T0500Z-210422T1300Z/ Sussex-Warren-Morris-Hunterdon-Somerset-Berks-Lehigh-Northampton- Western Montgomery-Upper Bucks- Including the cities of Newton, Washington, Morristown, Flemington, Somerville, Reading, Allentown, Bethlehem, Easton, Collegeville, Pottstown, Chalfont, and Perkasie 326 AM EDT Wed Apr 21 2021 ...FREEZE WARNING IN EFFECT FROM 1 AM TO 9 AM EDT THURSDAY... * WHAT...Sub-freezing temperatures in the mid 20s to lower 30s expected. * WHERE...In New Jersey, Sussex, Warren, Morris, Hunterdon, and Somerset Counties. In Pennsylvania, Berks, Lehigh, Northampton, Western Montgomery, and Upper Bucks Counties. * WHEN...From 1 AM to 9 AM EDT Thursday. * IMPACTS...Frost and freeze conditions will kill crops and other sensitive vegetation. PRECAUTIONARY/PREPAREDNESS ACTIONS... Take steps now to protect tender plants from the cold. && $$ PAZ101-102-212100- /O.NEW.KPHI.FZ.W.0003.210422T0500Z-210422T1300Z/ Western Chester-Eastern Chester- Including the cities of Honey Brook, Oxford, West Chester, and Kennett Square 326 AM EDT Wed Apr 21 2021 ...FREEZE WARNING IN EFFECT FROM 1 AM TO 9 AM EDT THURSDAY... * WHAT...Sub-freezing temperatures around 30 degrees expected. * WHERE...Chester County in Pennsylvania. * WHEN...From 1 AM to 9 AM EDT Thursday. * IMPACTS...Frost and freeze conditions will kill crops and other sensitive vegetation. PRECAUTIONARY/PREPAREDNESS ACTIONS... Take steps now to protect tender plants from the cold. && $$ CMS
3 follow-up statements
588 WWUS71 KPHI 211958 NPWPHI URGENT - WEATHER MESSAGE National Weather Service Mount Holly NJ 358 PM EDT Wed Apr 21 2021 NJZ001-007>010-PAZ060>062-101>103-105-220900- /O.CON.KPHI.FZ.W.0003.210422T0500Z-210422T1300Z/ Sussex-Warren-Morris-Hunterdon-Somerset-Berks-Lehigh-Northampton- Western Chester-Eastern Chester-Western Montgomery-Upper Bucks- Including the cities of Newton, Washington, Morristown, Flemington, Somerville, Reading, Allentown, Bethlehem, Easton, Honey Brook, Oxford, West Chester, Kennett Square, Collegeville, Pottstown, Chalfont, and Perkasie 358 PM EDT Wed Apr 21 2021 ...FREEZE WARNING REMAINS IN EFFECT FROM 1 AM TO 9 AM EDT THURSDAY... * WHAT...Sub-freezing temperatures in the upper 20s to lower 30s expected. * WHERE...Portions of northern and northwest New Jersey and east central and southeast Pennsylvania. * WHEN...From 1 AM to 9 AM EDT Thursday. * IMPACTS...Frost and freeze conditions will kill crops and other sensitive vegetation. PRECAUTIONARY/PREPAREDNESS ACTIONS... Take steps now to protect tender plants from the cold. && $$ Staarmann
380 WWUS71 KPHI 220639 NPWPHI URGENT - WEATHER MESSAGE National Weather Service Mount Holly NJ 239 AM EDT Thu Apr 22 2021 NJZ001-007>010-PAZ060>062-101>103-105-221300- /O.CON.KPHI.FZ.W.0003.000000T0000Z-210422T1300Z/ Sussex-Warren-Morris-Hunterdon-Somerset-Berks-Lehigh-Northampton- Western Chester-Eastern Chester-Western Montgomery-Upper Bucks- Including the cities of Newton, Washington, Morristown, Flemington, Somerville, Reading, Allentown, Bethlehem, Easton, Honey Brook, Oxford, West Chester, Kennett Square, Collegeville, Pottstown, Chalfont, and Perkasie 239 AM EDT Thu Apr 22 2021 ...FREEZE WARNING REMAINS IN EFFECT UNTIL 9 AM EDT THIS MORNING... * WHAT...Sub-freezing temperatures in the upper 20s to lower 30s expected. * WHERE...Portions of northern and northwest New Jersey and east central and southeast Pennsylvania. * WHEN...Until 9 AM EDT this morning. * IMPACTS...Frost and freeze conditions will kill crops and other sensitive vegetation. * ADDITIONAL DETAILS...Freezing conditions are likely again tonight into Friday morning for much of the warned area. PRECAUTIONARY/PREPAREDNESS ACTIONS... Take steps now to protect tender plants from the cold. && $$ Johnson
746 WWUS71 KPHI 221258 NPWPHI URGENT - WEATHER MESSAGE National Weather Service Mount Holly NJ 858 AM EDT Thu Apr 22 2021 NJZ001-007>010-PAZ060>062-101>103-105-222000- /O.EXP.KPHI.FZ.W.0003.000000T0000Z-210422T1300Z/ /O.NEW.KPHI.FZ.A.0003.210423T0500Z-210423T1300Z/ Sussex-Warren-Morris-Hunterdon-Somerset-Berks-Lehigh-Northampton- Western Chester-Eastern Chester-Western Montgomery-Upper Bucks- Including the cities of Newton, Washington, Morristown, Flemington, Somerville, Reading, Allentown, Bethlehem, Easton, Honey Brook, Oxford, West Chester, Kennett Square, Collegeville, Pottstown, Chalfont, and Perkasie 858 AM EDT Thu Apr 22 2021 ...FREEZE WATCH IN EFFECT FROM LATE TONIGHT THROUGH FRIDAY MORNING... ...FREEZE WARNING WILL EXPIRE AT 9 AM EDT THIS MORNING... * WHAT...Sub-freezing temperatures as low as 30 to 32 possible. * WHERE...Portions of northern New Jersey and eastern Pennsylvania. * WHEN...From late tonight through Friday morning. * IMPACTS...Freeze conditions will kill crops and other sensitive vegetation. PRECAUTIONARY/PREPAREDNESS ACTIONS... Take steps now to protect tender plants from the cold. && $$ NJZ012-015-PAZ104-106-222000- /O.NEW.KPHI.FZ.A.0003.210423T0500Z-210423T1300Z/ Middlesex-Mercer-Eastern Montgomery-Lower Bucks- Including the cities of New Brunswick, Trenton, Norristown, Lansdale, Morrisville, and Doylestown 858 AM EDT Thu Apr 22 2021 ...FREEZE WATCH IN EFFECT FROM LATE TONIGHT THROUGH FRIDAY MORNING... * WHAT...Sub-freezing temperatures as low as 32 possible. * WHERE...In New Jersey, Middlesex and Mercer. In Pennsylvania, Eastern Montgomery and Lower Bucks. * WHEN...From late tonight through Friday morning. * IMPACTS...Freeze conditions will kill crops and other sensitive vegetation. PRECAUTIONARY/PREPAREDNESS ACTIONS... Take steps now to protect tender plants from the cold. && $$ NJZ013-020>022-027-222000- /O.NEW.KPHI.FZ.A.0003.210423T0500Z-210423T1300Z/ Western Monmouth-Ocean-Cumberland-Atlantic- Southeastern Burlington- Including the cities of Freehold, Jackson, Millville, Hammonton, and Wharton State Forest 858 AM EDT Thu Apr 22 2021 ...FREEZE WATCH IN EFFECT FROM LATE TONIGHT THROUGH FRIDAY MORNING... * WHAT...Sub-freezing temperatures as low as 30 to 32 possible. * WHERE...Western Monmouth, Ocean, Cumberland, Atlantic and Southeastern Burlington. * WHEN...From late tonight through Friday morning. * IMPACTS...Freeze conditions will kill crops and other sensitive vegetation. PRECAUTIONARY/PREPAREDNESS ACTIONS... Take steps now to protect tender plants from the cold. && $$
The office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 20, 8:48 PM EDT | Freeze Watch | PHI | Hunterdon, Morris, Somerset, Sussex, Warren | 7 hr |
| Apr 21, 12:25 PM EDT | Severe Thunderstorm Warning | PHI | Warren | 50 min |
| Apr 21, 12:51 PM EDT | Severe Thunderstorm Warning | PHI | Sussex, Warren | 21 min |
| Apr 21, 12:55 PM EDT | Severe Thunderstorm Warning | PHI | Hunterdon, Warren | 27 min |
| Apr 21, 1:10 PM EDT | Severe Thunderstorm Warning | PHI | Burlington, Camden, Gloucester, Mercer, Salem | 50 min |
| Apr 21, 1:17 PM EDT | Special Weather Statement | PHI | Hunterdon, Morris, Somerset, Sussex | 58 min |
| Apr 21, 1:28 PM EDT | Severe Thunderstorm Warning | PHI | Atlantic, Burlington, Camden, Gloucester | 36 min |
| Apr 21, 1:30 PM EDT | Special Marine Warning | PHI | 60 min | |
| Apr 21, 1:43 PM EDT | Severe Thunderstorm Warning | PHI | Hunterdon, Middlesex, Morris, Somerset | 33 min |
| Apr 21, 1:58 PM EDT | Special Weather Statement | PHI | Burlington, Camden, Monmouth, Ocean | 62 min |
| Apr 21, 2:02 PM EDT | Severe Thunderstorm Warning | PHI | Burlington, Camden, Monmouth, Ocean | 43 min |
| Apr 21, 2:03 PM EDT | Special Weather Statement | PHI | Cumberland | 27 min |
| Apr 21, 2:17 PM EDT | Severe Thunderstorm Warning | PHI | Atlantic, Cumberland, Gloucester, Salem | 43 min |
| Apr 21, 2:28 PM EDT | Special Weather Statement | PHI | Middlesex, Monmouth | 47 min |
| Apr 21, 2:30 PM EDT | Special Marine Warning | PHI | 60 min | |
| Apr 21, 2:38 PM EDT | Severe Thunderstorm Warning | PHI | Monmouth, Ocean | 37 min |
| Apr 21, 2:40 PM EDT | Special Marine Warning | PHI | 55 min | |
| Apr 21, 2:43 PM EDT | Special Weather Statement | PHI | Cape May | 32 min |
| Apr 21, 2:50 PM EDT | Severe Thunderstorm Warning | PHI | Atlantic, Burlington, Ocean | 40 min |
| Apr 21, 3:02 PM EDT | Severe Thunderstorm Warning | PHI | Atlantic | 28 min |
| Apr 21, 3:07 PM EDT | Special Marine Warning | PHI | 53 min | |
| Apr 21, 12:03 PM EDT | Special Weather Statement | PHI | Chester, Lehigh | 42 min |
| Apr 21, 12:17 PM EDT | Severe Thunderstorm Warning | PHI | Berks, Bucks, Chester, Lehigh, Montgomery, Northampton | 43 min |
| Apr 21, 12:54 PM EDT | Special Weather Statement | PHI | Delaware | 36 min |
Nearby
Freeze Warnings in Pennsylvania, 2021Freeze Warnings in New Jersey, 2021Every freeze warning in 2021
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.