Alert archive / New Jersey / Heat Advisories in 2017

Heat Advisory 4, NWS Philadelphia/Mount Holly

July 20, 20174 states

NWS Philadelphia/Mount Holly issued this heat advisory at Jul 20, 2017, 3:43 AM EDT for 4 states. It took effect at Jul 20, 2017, 12:00 PM EDT. It was in force for 7 hr.

The area

The counties it named.

The facts

Issued
Jul 20, 2017, 3:43 AM EDT (07:43 UTC)
In effect from
Jul 20, 2017, 12:00 PM EDT
Expired
Jul 20, 2017, 7:00 PM EDT
In force
7 hr
Issued by
NWS Philadelphia/Mount Holly
All 23 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, Cape May County, NJ, Cumberland County, NJ, Hunterdon County, NJ, Middlesex County, NJ, Monmouth County, NJ, Ocean County, NJ, Salem County, NJ, Somerset 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), 75 km from the middle of the area, began a volume at 07:47 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

Wallops Is Stn, VA (KWAL), launched 00:00Z, 7.7 hours before the alert went out and 204 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, Wallops Is Stn, VA at 00:00Z on 2017-07-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 904 joules per kilogram.LCLLFCEL10008507005003002001001 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, Wallops Is Stn, VA at 00:00Z on 2017-07-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 58 square meters per square second.1939Sfc1 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
904 J/kg
Mixed-layer CIN
-69 J/kg
Mixed-layer LCL
1072 m above ground
0-6 km bulk shear
21 kt
0-1 km storm-relative helicity
58 m²/s²
0-3 km storm-relative helicity
90 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.9

Open this sounding in Storm Lab

The text

As transmitted.

909 
WWUS71 KPHI 200743
NPWPHI

URGENT - WEATHER MESSAGE
National Weather Service Mount Holly NJ
343 AM EDT Thu Jul 20 2017

DEZ001-NJZ015-017>019-PAZ070-071-102-104-106-202000-
/O.CON.KPHI.EH.W.0002.170720T1600Z-170722T0000Z/
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
343 AM EDT Thu Jul 20 2017

...EXCESSIVE HEAT WARNING REMAINS IN EFFECT FROM NOON TODAY TO
8 PM EDT FRIDAY...

* TEMPERATURES...High temperatures are forecast to be in the
  middle 90s both today and Friday. There will not be much relief
  at night with low temperatures in the 70s.

* HEAT INDEX VALUES...Generally from 98 to 105 degrees during the
  afternoon hours on Thursday and Friday.

* IMPACTS...The heat and humidity may cause heat stress during
  outdoor exertion or extended exposure. Excessive heat can be
  life-threatening among at-risk populations, such as children,
  the elderly, and those with pre-existing health conditions.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Take extra precautions if you work or spend time outside. When
possible, reschedule strenuous activities to the early morning or
the late evening. Know the signs and symptoms of heat exhaustion
and heat stroke. Wear light weight and loose fitting clothing and
be sure to drink plenty of water.

To reduce your risk during outdoor work the Occupational Safety
and Health Administration recommends scheduling frequent rest
breaks in a shaded or air conditioned environment. Anyone
overcome by heat should be moved to a cool shaded location. Heat
stroke is an emergency...call 9 1 1.

An Excessive Heat Warning means that a prolonged period of very
hot temperatures and high humidity will occur. The combination
will create a dangerous situation in which heat related health
problems may develop. Drink plenty of fluids, stay in an air
conditioned environment, stay out of the sun and be sure to check
on elderly relatives and neighbors.

Young children and pets should never be left unattended in a
vehicle under any circumstance. This is especially true during
hot weather when a car's interior can reach lethal temperatures
in a matter of minutes.

&&

$$

DEZ002-003-MDZ008-012-015-019-020-NJZ009-010-012-013-016-020>023-
027-PAZ060>062-101-103-105-202000-
/O.NEW.KPHI.HT.Y.0004.170720T1600Z-170720T2300Z/
Kent-Inland Sussex-Cecil-Kent MD-Queen Annes-Talbot-Caroline-
Hunterdon-Somerset-Middlesex-Western Monmouth-Salem-Ocean-
Cumberland-Atlantic-Cape May-Southeastern Burlington-Berks-Lehigh-
Northampton-Western Chester-Western Montgomery-Upper Bucks-
Including the cities of Dover, Georgetown, Elkton, Chestertown, 
Centreville, Easton, Denton, Flemington, Somerville, 
New Brunswick, Freehold, Pennsville, Jackson, Millville, 
Hammonton, Cape May Court House, Wharton State Forest, Reading, 
Allentown, Bethlehem, Honey Brook, Oxford, Collegeville, 
Pottstown, Chalfont, and Perkasie
343 AM EDT Thu Jul 20 2017

...HEAT ADVISORY IN EFFECT FROM NOON TODAY TO 7 PM EDT THIS
EVENING...

The National Weather Service in Mount Holly has issued a Heat
Advisory, which is in effect from noon today to 7 PM EDT this
evening.

* HEAT INDEX VALUES...From 100 to 105 in southeast Pennsylvania
  and central New Jersey and 103 to 108 in Delaware, the Eastern
  Shore of Maryland, and southern New Jersey.

* TIMING...This afternoon into early this evening.

* IMPACTS...The heat and humidity may cause heat stress during 
  outdoor exertion or extended exposure.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Heat Advisory means that a period of hot temperatures is
expected. The combination of hot temperatures and high humidity
will combine to create a situation in which heat illnesses are
possible. Drink plenty of fluids...stay in an air-conditioned
room...stay out of the sun...and check up on relatives and
neighbors.

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 light weight and loose fitting clothing when possible
and drink plenty of water.

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.

&&

$$

CMS
2 follow-up statements
446 
WWUS71 KPHI 201322
NPWPHI

URGENT - WEATHER MESSAGE
National Weather Service Mount Holly NJ
922 AM EDT Thu Jul 20 2017

DEZ001-NJZ015-017>019-PAZ070-071-102-104-106-210200-
/O.CON.KPHI.EH.W.0002.170720T1600Z-170722T0000Z/
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
922 AM EDT Thu Jul 20 2017

...EXCESSIVE HEAT WARNING REMAINS IN EFFECT UNTIL 8 PM EDT
FRIDAY...

* TEMPERATURES...High temperatures are forecast to be in the 
  middle 90s both today and Friday. There will not be much relief 
  at night with low temperatures in the 70s.

* HEAT INDEX VALUES...Generally from 98 to 105 degrees during the
  afternoon hours today and Friday.

* IMPACTS...The heat and humidity may cause heat stress during
  outdoor exertion or extended exposure. Excessive heat can be
  life-threatening among at-risk populations, such as children, 
  the elderly, and those with pre-existing health conditions.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Take extra precautions if you work or spend time outside. When 
possible, reschedule strenuous activities to the early morning or 
the late evening. Know the signs and symptoms of heat exhaustion 
and heat stroke. Wear light weight and loose fitting clothing and 
be sure to drink plenty of water.

To reduce your risk during outdoor work the Occupational Safety 
and Health Administration recommends scheduling frequent rest 
breaks in a shaded or air conditioned environment. Anyone overcome
by heat should be moved to a cool shaded location. Heat stroke is
an emergency...call 9 1 1.

An Excessive Heat Warning means that a prolonged period of very 
hot temperatures and high humidity will occur. The combination 
will create a dangerous situation in which heat related health 
problems may develop. Drink plenty of fluids, stay in an air 
conditioned environment, stay out of the sun and be sure to check 
on elderly relatives and neighbors.

Young children and pets should never be left unattended in a 
vehicle under any circumstance. This is especially true during hot
weather when a car's interior can reach lethal temperatures in a 
matter of minutes.

&&

$$

DEZ002-003-MDZ008-012-015-019-020-NJZ009-010-012-013-016-020>023-
027-PAZ060>062-101-103-105-202300-
/O.CON.KPHI.HT.Y.0004.170720T1600Z-170720T2300Z/
Kent-Inland Sussex-Cecil-Kent MD-Queen Annes-Talbot-Caroline-
Hunterdon-Somerset-Middlesex-Western Monmouth-Salem-Ocean-
Cumberland-Atlantic-Cape May-Southeastern Burlington-Berks-Lehigh-
Northampton-Western Chester-Western Montgomery-Upper Bucks-
Including the cities of Dover, Georgetown, Elkton, Chestertown, 
Centreville, Easton, Denton, Flemington, Somerville, 
New Brunswick, Freehold, Pennsville, Jackson, Millville, 
Hammonton, Cape May Court House, Wharton State Forest, Reading, 
Allentown, Bethlehem, Honey Brook, Oxford, Collegeville, 
Pottstown, Chalfont, and Perkasie
922 AM EDT Thu Jul 20 2017

...HEAT ADVISORY REMAINS IN EFFECT UNTIL 7 PM EDT THIS EVENING...

* HEAT INDEX VALUES...From 100 to 105 in southeast Pennsylvania 
  and central New Jersey and 103 to 108 in Delaware, the Eastern 
  Shore of Maryland, and southern New Jersey.

* TIMING...This afternoon into early this evening.

* IMPACTS...The heat and humidity may cause heat stress during 
  outdoor exertion or extended exposure.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Heat Advisory means that a period of hot temperatures is 
expected. The combination of hot temperatures and high humidity 
will combine to create a situation in which heat illnesses are 
possible. Drink plenty of fluids...stay in an air-conditioned 
room...stay out of the sun...and check up on relatives and 
neighbors.

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 light weight and loose fitting clothing when possible
and drink plenty of water.

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.

&&

$$
838 
WWUS71 KPHI 201913
NPWPHI

URGENT - WEATHER MESSAGE
National Weather Service Mount Holly NJ
313 PM EDT Thu Jul 20 2017

DEZ001-NJZ015-017>019-PAZ070-071-102-104-106-210715-
/O.CON.KPHI.EH.W.0002.000000T0000Z-170722T0000Z/
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
313 PM EDT Thu Jul 20 2017

...EXCESSIVE HEAT WARNING REMAINS IN EFFECT UNTIL 8 PM EDT
FRIDAY...

* TEMPERATURES...High temperatures are forecast to be in the
  middle 90s for the remainder of this afternoon and again on 
  Friday. There will not be much relief overnight with 
  temperatures mostly falling back into the 70s, but remaining 
  near 80 in highly urbanized areas.

* HEAT INDEX VALUES...Generally from 98 to 105 degrees during the
  afternoon hours today and on Friday.

* IMPACTS...The heat and humidity may cause heat stress during 
  outdoor exertion or extended exposure.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Take extra precautions if you work or spend time outside. When
possible, reschedule strenuous activities to the early morning or
the late evening. Know the signs and symptoms of heat exhaustion
and heat stroke. Wear light weight and loose fitting clothing and
be sure to drink plenty of water.

To reduce your risk during outdoor work the Occupational Safety
and Health Administration recommends scheduling frequent rest
breaks in a shaded or air conditioned environment. Anyone
overcome by heat should be moved to a cool shaded location. Heat
stroke is an emergency...call 9 1 1.

An Excessive Heat Warning means that a prolonged period of very
hot temperatures and high humidity will occur. The combination
will create a dangerous situation in which heat related health
problems may develop. Drink plenty of fluids, stay in an air
conditioned environment, stay out of the sun and be sure to check
on elderly relatives and neighbors.

Young children and pets should never be left unattended in a
vehicle under any circumstance. This is especially true during
hot weather when a car's interior can reach lethal temperatures
in a matter of minutes.

&&

$$

DEZ002-003-MDZ008-012-015-019-020-NJZ009-010-012-013-016-020>023-
027-PAZ060>062-101-103-105-202300-
/O.CON.KPHI.HT.Y.0004.000000T0000Z-170720T2300Z/
Kent-Inland Sussex-Cecil-Kent MD-Queen Annes-Talbot-Caroline-
Hunterdon-Somerset-Middlesex-Western Monmouth-Salem-Ocean-
Cumberland-Atlantic-Cape May-Southeastern Burlington-Berks-Lehigh-
Northampton-Western Chester-Western Montgomery-Upper Bucks-
Including the cities of Dover, Georgetown, Elkton, Chestertown, 
Centreville, Easton, Denton, Flemington, Somerville, 
New Brunswick, Freehold, Pennsville, Jackson, Millville, 
Hammonton, Cape May Court House, Wharton State Forest, Reading, 
Allentown, Bethlehem, Honey Brook, Oxford, Collegeville, 
Pottstown, Chalfont, and Perkasie
313 PM EDT Thu Jul 20 2017

...HEAT ADVISORY REMAINS IN EFFECT UNTIL 7 PM EDT THIS EVENING...

* HEAT INDEX VALUES...From 100 to 104 in southeast Pennsylvania
  and central New Jersey and 101 to 106 in Delaware, the Eastern 
  Shore of Maryland, and southern New Jersey. 

* TIMING...This afternoon into early this evening. For Friday,
  Heat Index values will be in the upper 90s to 104 degrees. These
  values fall just under Heat Advisory criteria.

* IMPACTS...The heat and humidity may cause heat stress during 
  outdoor exertion or extended exposure.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Heat Advisory means that a period of hot temperatures is
expected. The combination of hot temperatures and high humidity
will combine to create a situation in which heat illnesses are
possible. Drink plenty of fluids...stay in an air-conditioned
room...stay out of the sun...and check up on relatives and
neighbors.

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 light weight and loose fitting clothing when
possible and drink plenty of water.

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.

IssuedProductOfficeCountiesLasted
Jul 20, 5:35 PM EDTSevere Thunderstorm WarningPHICarbon, Monroe55 min
Jul 20, 5:37 PM EDTSevere Thunderstorm WarningPHIMonroe53 min
Jul 20, 6:22 PM EDTSevere Thunderstorm WarningPHIBerks, Carbon, Lehigh, Monroe, Northampton53 min
Jul 20, 6:24 PM EDTSevere Thunderstorm WarningPHIMonroe, Northampton66 min
Jul 20, 7:00 PM EDTSevere Thunderstorm WarningPHIBucks, Carbon, Lehigh, Northampton60 min
Jul 20, 7:52 PM EDTSevere Thunderstorm WarningPHIBucks53 min
Jul 20, 7:31 PM EDTSpecial Weather StatementPHIMorris29 min
Jul 20, 7:56 PM EDTSpecial Weather StatementPHIMiddlesex, Monmouth, Somerset49 min

Nearby

Heat Advisories in New Jersey, 2017Heat Advisories in Pennsylvania, 2017Heat Advisories in Maryland, 2017Every heat advisory in 2017

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.