Alert archive / New Jersey / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 74, NWS Philadelphia/Mount Holly

June 9, 2021Burlington County, Mercer County, Monmouth County, New Jersey; Bucks County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jun 9, 2021, 5:32 PM EDT for Burlington County, Mercer County, Monmouth County, New Jersey; Bucks County, Pennsylvania. It was in force for 28 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Jun 9, 2021, 5:32 PM EDT (21:32 UTC)
Expired
Jun 9, 2021, 6:00 PM EDT
In force
28 min
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

Counties Burlington County, NJ, Mercer County, NJ, Monmouth County, NJ, Bucks County, PA

The radar

The Philadelphia radar (KDIX), 43 km from the middle of the area, began a volume at 21:34 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.

What was reported inside it

TimeReportWhereRemark
Jun 9, 5:35 PM EDTTSTM WND DMG2 Ssw Ewing, NJTREE DOWN ON AN APARTMENT BUILDING OFF SULLIVAN WAY. TIME ESTIMATED FROM RADAR.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 9.5 hours before the alert went out and 177 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, Brookhaven, NY at 12:00Z on 2021-06-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 556 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, Brookhaven, NY at 12:00Z on 2021-06-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 41 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
556 J/kg
Mixed-layer CIN
-80 J/kg
Mixed-layer LCL
927 m above ground
0-6 km bulk shear
23 kt
0-1 km storm-relative helicity
41 m²/s²
0-3 km storm-relative helicity
77 m²/s²
Significant tornado parameter
0.1
Supercell composite
0.5

Open this sounding in Storm Lab

The text

As transmitted.

543 
WUUS51 KPHI 092132
SVRPHI
NJC005-021-025-PAC017-092200-
/O.NEW.KPHI.SV.W.0074.210609T2132Z-210609T2200Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
532 PM EDT Wed Jun 9 2021

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  Mercer County in central New Jersey...
  North central Burlington County in southern New Jersey...
  Southwestern Monmouth County in central New Jersey...
  East central Bucks County in southeastern Pennsylvania...

* Until 600 PM EDT.

* At 531 PM EDT, a severe thunderstorm was located over Yardley, or
  over Trenton, moving southeast at 10 mph.

  HAZARD...60 mph wind gusts and penny size hail.

  SOURCE...Radar indicated.

  IMPACT...Damage to roofs, siding, trees, and power lines is 
           possible.

* Locations impacted include...
  Trenton, Ewing, Hightstown, Bordentown, Pennington, Yardley,
  Tullytown, Allentown, Washington Crossing, Edinburg, Crosswicks,
  White Horse, Windsor, Mercerville-Hamilton Square, Lawrenceville,
  Woodside, Georgetown, Levittown, Florence-Roebling and Morrisville.

This includes the following highways...
 New Jersey Turnpike between exits 7 and 8.
 Interstate 195 in New Jersey between mile markers 0 and 9.
 Interstate 295 in New Jersey between mile markers 54 and 76.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

&&

LAT...LON 4021 7494 4035 7483 4026 7450 4004 7466
TIME...MOT...LOC 2131Z 300DEG 9KT 4024 7481 

HAIL...0.75IN
WIND...60MPH
 
$$

Fitzsimmons
2 follow-up statements
845 
WWUS51 KPHI 092140
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
540 PM EDT Wed Jun 9 2021

NJC005-021-025-PAC017-092200-
/O.CON.KPHI.SV.W.0074.000000T0000Z-210609T2200Z/
Mercer NJ-Burlington NJ-Monmouth NJ-Bucks PA-
540 PM EDT Wed Jun 9 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 600 PM EDT
FOR MERCER...NORTH CENTRAL BURLINGTON...SOUTHWESTERN MONMOUTH AND
EAST CENTRAL BUCKS COUNTIES...

At 540 PM EDT, a severe thunderstorm was located over Trenton, moving
southeast at 10 mph.

HAZARD...60 mph wind gusts and penny size hail.

SOURCE...Radar indicated.

IMPACT...Damage to roofs, siding, trees, and power lines is 
         possible.

Locations impacted include...
Trenton, Ewing, Hightstown, Bordentown, Pennington, Yardley,
Tullytown, Allentown, Washington Crossing, Edinburg, Crosswicks,
White Horse, Windsor, Mercerville-Hamilton Square, Lawrenceville,
Woodside, Georgetown, Levittown, Florence-Roebling and Morrisville.

This includes the following highways...
 New Jersey Turnpike between exits 7 and 8.
 Interstate 195 in New Jersey between mile markers 0 and 9.
 Interstate 295 in New Jersey between mile markers 54 and 76.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

For your protection move to an interior room on the lowest floor of a
building.

Torrential rainfall is occurring with this storm, and may lead to
flash flooding. Do not drive your vehicle through flooded roadways.

&&

LAT...LON 4021 7494 4035 7483 4026 7450 4004 7466
TIME...MOT...LOC 2140Z 300DEG 9KT 4023 7478 

HAIL...0.75IN
WIND...60MPH
 
$$

Fitzsimmons
143 
WWUS51 KPHI 092150 RRA
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
550 PM EDT Wed Jun 9 2021

NJC005-021-025-PAC017-092200-
/O.EXP.KPHI.SV.W.0074.000000T0000Z-210609T2200Z/
Mercer NJ-Burlington NJ-Monmouth NJ-Bucks PA-
550 PM EDT Wed Jun 9 2021

...THE SEVERE THUNDERSTORM WARNING FOR MERCER...NORTH CENTRAL
BURLINGTON...SOUTHWESTERN MONMOUTH AND EAST CENTRAL BUCKS COUNTIES
WILL EXPIRE AT 600 PM EDT...
                
The storm which prompted the warning has weakened below severe
limits, and no longer poses an immediate threat to life or property.
Therefore, the warning will be allowed to expire.  However heavy rain
is still possible with this thunderstorm.

To report severe weather, contact your nearest law enforcement
agency. They will relay your report to the National Weather Service
Mount Holly NJ.

LAT...LON 4021 7494 4035 7483 4026 7450 4004 7466
TIME...MOT...LOC 2150Z 300DEG 9KT 4022 7475 

$$

Fitzsimmons

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 8, 8:40 PM EDTSpecial Marine WarningPHI65 min
Jun 9, 1:46 PM EDTSpecial Marine WarningPHI59 min
Jun 9, 1:48 PM EDTSpecial Weather StatementPHISalem27 min
Jun 9, 1:52 PM EDTSpecial Weather StatementPHIAtlantic23 min
Jun 9, 2:07 PM EDTSevere Thunderstorm WarningPHIGloucester, Salem23 min
Jun 9, 2:14 PM EDTSpecial Weather StatementPHISalem31 min
Jun 9, 2:21 PM EDTFlash Flood WarningPHICumberland, Gloucester, Salem73 min
Jun 9, 2:47 PM EDTSpecial Marine WarningPHI58 min
Jun 9, 3:32 PM EDTSpecial Weather StatementPHIBurlington28 min
Jun 9, 3:48 PM EDTSpecial Marine WarningPHI57 min
Jun 9, 3:49 PM EDTFlash Flood WarningPHIBurlington3 hr
Jun 9, 3:51 PM EDTSpecial Weather StatementPHIHunterdon24 min
Jun 9, 6:46 PM EDTSpecial Marine WarningPHI59 min
Jun 9, 6:50 PM EDTAreal Flood AdvisoryPHIMonmouth, Ocean87 min
Jun 9, 7:42 PM EDTSpecial Marine WarningPHI63 min
Jun 9, 4:54 PM EDTFlash Flood WarningPHIBerks, Montgomery112 min
Jun 9, 5:27 PM EDTSevere Thunderstorm WarningPHIBerks, Lehigh, Northampton23 min

Nearby

Severe Thunderstorm Warnings in New Jersey, 2021Severe Thunderstorm Warnings in Pennsylvania, 2021Every severe thunderstorm 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.