Alert archive / New Jersey / Excessive Heat Watches in 2021
Excessive Heat Watch 1, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this excessive heat watch at Aug 9, 2021, 3:43 PM EDT for 5 counties in Pennsylvania; New Castle County, Delaware; 10 counties in New Jersey. It took effect at Aug 11, 2021, 12:00 PM EDT. It was in force for .
The area
The counties it named.
The facts
- Issued
- Aug 9, 2021, 3:43 PM EDT (19:43 UTC)
- In effect from
- Aug 11, 2021, 12:00 PM EDT
- Expired
- Aug 10, 2021, 3:33 AM EDT
- In force
- Issued by
- NWS Philadelphia/Mount Holly
Counties New Castle County, DE, Burlington County, NJ, Camden County, NJ, Gloucester County, NJ, Hunterdon County, NJ, Mercer County, NJ, Middlesex County, NJ, Monmouth County, NJ, Morris County, NJ, Ocean County, NJ, Somerset County, NJ, Bucks County, PA, Chester County, PA, Delaware County, PA, Montgomery County, PA, Philadelphia County, PA
The radar
The Philadelphia radar (KDIX), 49 km from the middle of the area, began a volume at 19:43 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 12:00Z, 7.7 hours before the alert went out and 192 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
- 12 J/kg
- Mixed-layer CIN
- 0 J/kg
- Mixed-layer LCL
- 473 m above ground
- 0-6 km bulk shear
- 14 kt
- 0-1 km storm-relative helicity
- -2 m²/s²
- 0-3 km storm-relative helicity
- 10 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
273 WWUS71 KPHI 091943 NPWPHI URGENT - WEATHER MESSAGE National Weather Service Mount Holly NJ 343 PM EDT Mon Aug 9 2021 DEZ001-NJZ008>010-012-013-015-017>020-027-PAZ070-071-101>106- 101200- /O.NEW.KPHI.EH.A.0001.210811T1600Z-210814T0000Z/ New Castle-Morris-Hunterdon-Somerset-Middlesex-Western Monmouth- Mercer-Gloucester-Camden-Northwestern Burlington-Ocean- Southeastern Burlington-Delaware-Philadelphia-Western Chester- Eastern Chester-Western Montgomery-Eastern Montgomery-Upper Bucks- Lower Bucks- Including the cities of Wilmington, Morristown, Flemington, Somerville, New Brunswick, Freehold, Trenton, Glassboro, Camden, Cherry Hill, Moorestown, Mount Holly, Jackson, Wharton State Forest, Media, Philadelphia, Honey Brook, Oxford, West Chester, Kennett Square, Collegeville, Pottstown, Norristown, Lansdale, Chalfont, Perkasie, Morrisville, and Doylestown 343 PM EDT Mon Aug 9 2021 ...EXCESSIVE HEAT WATCH IN EFFECT FROM WEDNESDAY AFTERNOON THROUGH FRIDAY EVENING... * WHAT...Dangerously hot conditions with heat index values around 105 possible. * WHERE...Portions of central, northern, northwest and southern New Jersey, southeast Pennsylvania and northern Delaware. * WHEN...From Wednesday afternoon through Friday evening. * IMPACTS...Extreme heat and humidity will significantly increase the potential for heat related illnesses, particularly for those working or participating in outdoor activities. PRECAUTIONARY/PREPAREDNESS ACTIONS... Monitor the latest forecasts and warnings for updates on this situation. Be prepared to drink plenty of fluids, stay in an air- conditioned room, stay out of the sun, and check up on relatives and neighbors. Young children and pets should never be left unattended in vehicles under any circumstances. This is especially true during warm or hot weather when car interiors can reach lethal temperatures in a matter of minutes. && $$
1 follow-up statement
810 WWUS71 KPHI 100733 NPWPHI URGENT - WEATHER MESSAGE National Weather Service Mount Holly NJ 333 AM EDT Tue Aug 10 2021 DEZ001-NJZ008>010-012-013-015-017>020-027-PAZ070-071-101>106- 102130- /O.UPG.KPHI.EH.A.0001.210811T1600Z-210814T0000Z/ /O.NEW.KPHI.EH.W.0002.210811T1600Z-210813T0000Z/ New Castle-Morris-Hunterdon-Somerset-Middlesex-Western Monmouth- Mercer-Gloucester-Camden-Northwestern Burlington-Ocean- Southeastern Burlington-Delaware-Philadelphia-Western Chester- Eastern Chester-Western Montgomery-Eastern Montgomery-Upper Bucks- Lower Bucks- Including the cities of Wilmington, Morristown, Flemington, Somerville, New Brunswick, Freehold, Trenton, Glassboro, Camden, Cherry Hill, Moorestown, Mount Holly, Jackson, Wharton State Forest, Media, Philadelphia, Honey Brook, Oxford, West Chester, Kennett Square, Collegeville, Pottstown, Norristown, Lansdale, Chalfont, Perkasie, Morrisville, and Doylestown 333 AM EDT Tue Aug 10 2021 ...EXCESSIVE HEAT WARNING IN EFFECT FROM NOON WEDNESDAY TO 8 PM EDT THURSDAY... * WHAT...Dangerously hot conditions with heat index values to around 105 on Wednesday and up to 110 Thursday. * WHERE...Portions of central, northern, northwest and southern New Jersey, southeast Pennsylvania and northern Delaware. * WHEN...From noon Wednesday to 8 PM EDT Thursday. * IMPACTS...Extreme heat and humidity will significantly increase the potential for heat related illnesses, particularly for those working or participating in outdoor activities. * ADDITIONAL DETAILS...An extended period of excessively hot and humid conditions is expected Wednesday and Thursday and may continue through Friday. Overnight low temperatures in the mid 70s will not provide much relief from the heat. The hottest period is expected Thursday and Thursday night. PRECAUTIONARY/PREPAREDNESS ACTIONS... Drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors. Young children and pets should never be left unattended in vehicles under any circumstances. Take extra precautions if you work or spend time outside. When possible reschedule strenuous activities to early morning or evening. Know the signs and symptoms of heat exhaustion and heat stroke. Wear lightweight and loose fitting clothing when possible. To reduce risk during outdoor work, the Occupational Safety and Health Administration recommends scheduling frequent rest breaks in shaded or air conditioned environments. Anyone overcome by heat should be moved to a cool and shaded location. Heat stroke is an emergency! Call 9 1 1. && $$ NJZ001-007-014-026-PAZ060>062-102130- /O.NEW.KPHI.HT.Y.0008.210811T1600Z-210813T0000Z/ Sussex-Warren-Eastern Monmouth-Coastal Ocean-Berks-Lehigh- Northampton- Including the cities of Newton, Washington, Sandy Hook, Long Beach Island, Reading, Allentown, Bethlehem, and Easton 333 AM EDT Tue Aug 10 2021 ...HEAT ADVISORY IN EFFECT FROM NOON WEDNESDAY TO 8 PM EDT THURSDAY... * WHAT...Heat index values to around 100 on Wednesday and up to 104 Thursday. * WHERE...In New Jersey, Sussex, Warren, Eastern Monmouth and Coastal Ocean. In Pennsylvania, Berks, Lehigh and Northampton. * WHEN...From noon Wednesday to 8 PM EDT Thursday. * IMPACTS...Hot temperatures and high humidity may cause heat illnesses to occur. * ADDITIONAL DETAILS...An extended period of hot and humid conditions is expected Wednesday and Thursday and may continue through Friday. Overnight low temperatures in the low to mid 70s will not provide much relief from the heat. The hottest period is expected Thursday and Thursday night. PRECAUTIONARY/PREPAREDNESS ACTIONS... Drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors. Young children and pets should never be left unattended in vehicles under any circumstances. Take extra precautions if you work or spend time outside. When possible reschedule strenuous activities to early morning or evening. Know the signs and symptoms of heat exhaustion and heat stroke. Wear lightweight and loose fitting clothing when possible. To reduce risk during outdoor work, the Occupational Safety and Health Administration recommends scheduling frequent rest breaks in shaded or air conditioned environments. Anyone overcome by heat should be moved to a cool and shaded location. Heat stroke is an emergency! Call 9 1 1. && $$ DEZ002-003-MDZ012-015-019-020-NJZ016-021-022-102130- /O.NEW.KPHI.HT.Y.0008.210811T1600Z-210813T0000Z/ Kent-Inland Sussex-Kent MD-Queen Annes-Talbot-Caroline-Salem- Cumberland-Atlantic- Including the cities of Dover, Georgetown, Chestertown, Centreville, Easton, Denton, Pennsville, Millville, and Hammonton 333 AM EDT Tue Aug 10 2021 ...HEAT ADVISORY IN EFFECT FROM NOON WEDNESDAY TO 8 PM EDT THURSDAY... * WHAT...Heat index values to around 105 expected. * WHERE...In New Jersey, Salem, Cumberland and Atlantic. In Maryland, Kent MD, Queen Annes, Talbot and Caroline. In Delaware, Kent and Inland Sussex. * WHEN...From noon Wednesday to 8 PM EDT Thursday. * IMPACTS...Hot temperatures and high humidity may cause heat illnesses to occur. * ADDITIONAL DETAILS...An extended period of hot and humid conditions is expected Wednesday and Thursday and may continue through Friday. Overnight low temperatures in the mid 70s will not provide much relief from the heat. The hottest period is expected Thursday and Thursday night. PRECAUTIONARY/PREPAREDNESS ACTIONS... Drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors. Young children and pets should never be left unattended in vehicles under any circumstances. Take extra precautions if you work or spend time outside. When possible reschedule strenuous activities to early morning or evening. Know the signs and symptoms of heat exhaustion and heat stroke. Wear lightweight and loose fitting clothing when possible. To reduce risk during outdoor work, the Occupational Safety and Health Administration recommends scheduling frequent rest breaks in shaded or air conditioned environments. Anyone overcome by heat should be moved to a cool and shaded location. Heat stroke is an emergency! Call 9 1 1. && $$ Staarmann
The office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 9, 4:36 PM EDT | Areal Flood Advisory | PHI | Chester, Delaware | 104 min |
| Aug 9, 5:12 PM EDT | Areal Flood Advisory | PHI | Chester, Delaware | 85 min |
| Aug 9, 5:34 PM EDT | Special Weather Statement | PHI | Philadelphia | 26 min |
| Aug 9, 5:40 PM EDT | Areal Flood Advisory | PHI | Philadelphia | 82 min |
| Aug 9, 6:10 PM EDT | Special Weather Statement | PHI | Philadelphia | 35 min |
| Aug 9, 6:24 PM EDT | Special Weather Statement | PHI | Lehigh | 36 min |
| Aug 9, 6:29 PM EDT | Areal Flood Advisory | PHI | Berks, Montgomery | 70 min |
| Aug 9, 6:49 PM EDT | Special Weather Statement | PHI | Montgomery | 26 min |
| Aug 9, 7:14 PM EDT | Special Weather Statement | PHI | Carbon | 31 min |
| Aug 9, 2:10 PM EDT | Special Weather Statement | PHI | Sussex | 50 min |
| Aug 9, 2:41 PM EDT | Areal Flood Advisory | PHI | Kent, New Castle, Sussex | 3 hr |
| Aug 9, 3:01 PM EDT | Flash Flood Warning | PHI | Kent, Sussex | 2 hr |
| Aug 9, 4:35 PM EDT | Severe Thunderstorm Warning | PHI | Kent | 40 min |
| Aug 9, 4:59 PM EDT | Flash Flood Warning | PHI | Kent | 79 min |
| Aug 9, 5:12 PM EDT | Severe Thunderstorm Warning | PHI | Kent | 20 min |
| Aug 9, 4:45 PM EDT | Special Weather Statement | PHI | Atlantic | 30 min |
| Aug 9, 6:37 PM EDT | Special Weather Statement | PHI | Mercer | 38 min |
Nearby
Excessive Heat Watches in New Jersey, 2021Excessive Heat Watches in Pennsylvania, 2021Excessive Heat Watches in Delaware, 2021Every excessive heat watch 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.