Alert archive / Pennsylvania / Heat Advisories in 2021
Heat Advisory 2, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this heat advisory at Jun 21, 2021, 4:35 AM EDT for 4 counties in New Jersey; 5 counties in Pennsylvania; New Castle County, Delaware. It took effect at Jun 21, 2021, 11:00 AM EDT. It was in force for 9 hr.
The area
The counties it named.
The facts
- Issued
- Jun 21, 2021, 4:35 AM EDT (08:35 UTC)
- In effect from
- Jun 21, 2021, 11:00 AM EDT
- Expired
- Jun 21, 2021, 8:00 PM EDT
- In force
- 9 hr
- Issued by
- NWS Philadelphia/Mount Holly
Counties New Castle County, DE, Burlington County, NJ, Camden County, NJ, Gloucester County, NJ, Mercer County, NJ, Bucks County, PA, Chester County, PA, Delaware County, PA, Montgomery County, PA, Philadelphia County, PA
The radar
The Philadelphia radar (KDIX), 66 km from the middle of the area, began a volume at 08:35 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, 8.6 hours before the alert went out and 220 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
- 530 J/kg
- Mixed-layer CIN
- -82 J/kg
- Mixed-layer LCL
- 980 m above ground
- 0-6 km bulk shear
- 23 kt
- 0-1 km storm-relative helicity
- 73 m²/s²
- 0-3 km storm-relative helicity
- 129 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.9
The text
As transmitted.
753 WWUS71 KPHI 210835 NPWPHI URGENT - WEATHER MESSAGE National Weather Service Mount Holly NJ 435 AM EDT Mon Jun 21 2021 DEZ001-NJZ015-017>019-PAZ070-071-102-104-106-212145- /O.NEW.KPHI.HT.Y.0002.210621T1500Z-210622T0000Z/ New Castle-Mercer-Gloucester-Camden-Northwestern Burlington- Delaware-Philadelphia-Eastern Chester-Eastern Montgomery- Lower Bucks- Including the cities of Wilmington, Trenton, Glassboro, Camden, Cherry Hill, Moorestown, Mount Holly, Media, Philadelphia, West Chester, Kennett Square, Norristown, Lansdale, Morrisville, and Doylestown 435 AM EDT Mon Jun 21 2021 ...HEAT ADVISORY IN EFFECT FROM 11 AM THIS MORNING TO 8 PM EDT THIS EVENING... * WHAT...Heat index values up to 97 expected. * WHERE...In New Jersey, Mercer, Gloucester, Camden and Northwestern Burlington. In Pennsylvania, Delaware, Philadelphia, Eastern Chester, Eastern Montgomery and Lower Bucks. In Delaware, New Castle. * WHEN...From 11 AM this morning to 8 PM EDT this evening. * IMPACTS...Hot temperatures and high humidity may cause heat illnesses to occur. 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. && $$ Staarmann
1 follow-up statement
424 WWUS71 KPHI 211927 NPWPHI URGENT - WEATHER MESSAGE National Weather Service Mount Holly NJ 327 PM EDT Mon Jun 21 2021 DEZ001-NJZ015-017>019-PAZ070-071-102-104-106-220000- /O.CON.KPHI.HT.Y.0002.000000T0000Z-210622T0000Z/ New Castle-Mercer-Gloucester-Camden-Northwestern Burlington- Delaware-Philadelphia-Eastern Chester-Eastern Montgomery- Lower Bucks- Including the cities of Wilmington, Trenton, Glassboro, Camden, Cherry Hill, Moorestown, Mount Holly, Media, Philadelphia, West Chester, Kennett Square, Norristown, Lansdale, Morrisville, and Doylestown 327 PM EDT Mon Jun 21 2021 ...HEAT ADVISORY REMAINS IN EFFECT UNTIL 8 PM EDT THIS EVENING... * WHAT...Heat index values up to 98 expected. * WHERE...In New Jersey, Mercer, Gloucester, Camden and Northwestern Burlington. In Pennsylvania, Delaware, Philadelphia, Eastern Chester, Eastern Montgomery and Lower Bucks. In Delaware, New Castle. * WHEN...From 11 AM this morning to 8 PM EDT this evening. * IMPACTS...Hot temperatures and high humidity may cause heat illnesses to occur. PRECAUTIONARY/PREPAREDNESS ACTIONS... Drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors. Young children and pets should never be left unattended in vehicles under any circumstances. Take extra precautions if you work or spend time outside. When possible reschedule strenuous activities to early morning or evening. Know the signs and symptoms of heat exhaustion and heat stroke. Wear lightweight and loose fitting clothing when possible. To reduce risk during outdoor work, the Occupational Safety and Health Administration recommends scheduling frequent rest breaks in shaded or air conditioned environments. Anyone overcome by heat should be moved to a cool and shaded location. Heat stroke is an emergency! Call 9 1 1. && $$
The office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 21, 7:12 PM EDT | Severe Thunderstorm Warning | PHI | Burlington, Camden, Cumberland, Gloucester, Salem | 48 min |
| Jun 21, 7:24 PM EDT | Special Marine Warning | PHI | 66 min | |
| Jun 21, 7:38 PM EDT | Severe Thunderstorm Warning | PHI | Warren | 52 min |
| Jun 21, 7:43 PM EDT | Severe Thunderstorm Warning | PHI | Cumberland, Salem | 47 min |
| Jun 21, 7:55 PM EDT | Special Weather Statement | PHI | Atlantic, Burlington, Camden, Mercer, Ocean | 50 min |
| Jun 20, 9:27 PM EDT | Special Weather Statement | PHI | Schuylkill | 33 min |
| Jun 20, 9:55 PM EDT | Special Weather Statement | PHI | Lebanon | 35 min |
| Jun 20, 10:04 PM EDT | Areal Flood Advisory | PHI | Berks | 86 min |
| Jun 20, 10:27 PM EDT | Special Weather Statement | PHI | Berks | 33 min |
| Jun 21, 6:08 PM EDT | Severe Thunderstorm Warning | PHI | Berks, Lehigh | 52 min |
| Jun 21, 6:21 PM EDT | Severe Thunderstorm Warning | PHI | Chester, Delaware | 54 min |
| Jun 21, 7:02 PM EDT | Severe Thunderstorm Warning | PHI | Berks, Carbon, Lehigh, Northampton | 43 min |
| Jun 21, 6:47 PM EDT | Severe Thunderstorm Warning | PHI | Kent, New Castle | 58 min |
Nearby
Heat Advisories in Pennsylvania, 2021Heat Advisories in New Jersey, 2021Heat Advisories in Delaware, 2021Every heat advisory 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.