Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2021

Severe Thunderstorm Warning 271, NWS Philadelphia/Mount Holly

August 27, 2021Carbon County, Monroe County, Northampton County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Aug 27, 2021, 2:32 PM EDT for Carbon County, Monroe County, Northampton 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
Aug 27, 2021, 2:32 PM EDT (18:32 UTC)
Expired
Aug 27, 2021, 3:00 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 Carbon County, PA, Monroe County, PA, Northampton County, PA

The radar

The Philadelphia radar (KDIX), 131 km from the middle of the area, began a volume at 18:34 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
Aug 27, 2:34 PM EDTTSTM WND DMG2 Ssw Gilbert, PADOWNED TREE LIMBS AND WIRES NEAR BLACKBERRY LANE. 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, 6.5 hours before the alert went out and 207 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 2021-08-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1159 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 2021-08-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 19 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
1159 J/kg
Mixed-layer CIN
-60 J/kg
Mixed-layer LCL
1043 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
19 m²/s²
0-3 km storm-relative helicity
22 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

720 
WUUS51 KPHI 271832
SVRPHI
PAC025-089-095-271915-
/O.NEW.KPHI.SV.W.0271.210827T1832Z-210827T1915Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
Severe Thunderstorm Warning
National Weather Service Mount Holly NJ
232 PM EDT Fri Aug 27 2021

The National Weather Service in Mount Holly NJ has issued a

* Severe Thunderstorm Warning for...
  East central Carbon County in northeastern Pennsylvania...
  Southwestern Monroe County in northeastern Pennsylvania...
  Central Northampton County in eastern Pennsylvania...

* Until 315 PM EDT.

* At 232 PM EDT, a severe thunderstorm was located over Rossland, or
  14 miles northwest of Easton, and is nearly stationary.

  HAZARD...60 mph wind gusts.

  SOURCE...Radar indicated.

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

* Locations impacted include...
  Easton, East Stroudsburg, Nazareth, Bangor, Pen Argyl, Wind Gap,
  Belfast, Tatamy, East Bangor, Stormville, Brodheadsville,
  Kunkletown, Gilbert, Delaware Water Gap, Rossland, Kresgeville,
  Saylorsburg, Penn Forest Reservoir, Stroudsburg and Roseto.

This includes the following highways...
 Interstate 80 in Pennsylvania between mile markers 308 and 314.
 Interstate 80 in New Jersey near mile marker 0.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

In addition to damaging winds, frequent cloud to ground lightning is 
occurring with this storm. Move indoors immediately. Remember, if 
you can hear thunder, you are close enough to be struck by lightning.

&&

LAT...LON 4101 7512 4070 7521 4081 7557 4093 7562
TIME...MOT...LOC 1832Z 266DEG 2KT 4085 7539 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Gorse
2 follow-up statements
303 
WWUS51 KPHI 271847
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
247 PM EDT Fri Aug 27 2021

PAC025-271856-
/O.CAN.KPHI.SV.W.0271.000000T0000Z-210827T1915Z/
Carbon PA-
247 PM EDT Fri Aug 27 2021

...THE SEVERE THUNDERSTORM WARNING FOR EAST CENTRAL CARBON COUNTY IS
CANCELLED...
    
The severe thunderstorm which prompted the warning looks to remain 
out of this portion of the warned area. Therefore, the warning has 
been cancelled.

LAT...LON 4101 7512 4070 7521 4078 7549 4094 7547
TIME...MOT...LOC 1846Z 264DEG 8KT 4086 7531 

$$

PAC089-095-271915-
/O.CON.KPHI.SV.W.0271.000000T0000Z-210827T1915Z/
Monroe PA-Northampton PA-
247 PM EDT Fri Aug 27 2021

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 315 PM EDT
FOR SOUTH CENTRAL MONROE AND CENTRAL NORTHAMPTON COUNTIES...

At 246 PM EDT, a severe thunderstorm was located over Wind Gap, or 12
miles north of Easton, moving east at 10 mph.

HAZARD...60 mph wind gusts.

SOURCE...Radar indicated.

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

Locations impacted include...
Easton, East Stroudsburg, Nazareth, Bangor, Pen Argyl, Wind Gap,
Belfast, Tatamy, East Bangor, Stormville, Brodheadsville, Kunkletown,
Saylorsburg, Gilbert, Delaware Water Gap, Rossland, Stroudsburg,
Roseto, Stockertown and Chapman.

This includes the following highways...
 Interstate 80 in Pennsylvania between mile markers 309 and 314.
 Interstate 80 in New Jersey near mile marker 0.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

Frequent cloud to ground lightning is occurring with this storm. Move
indoors immediately. Lightning is one of nature's leading killers.
Remember, if you can hear thunder, you are close enough to be struck
by lightning.

&&

LAT...LON 4101 7512 4070 7521 4078 7549 4094 7547
TIME...MOT...LOC 1846Z 264DEG 8KT 4086 7531 

HAIL THREAT...RADAR INDICATED
MAX HAIL SIZE...<.75 IN
WIND THREAT...RADAR INDICATED
MAX WIND GUST...60 MPH

$$

Gorse
587 
WWUS51 KPHI 271900
SVSPHI

Severe Weather Statement
National Weather Service Mount Holly NJ
300 PM EDT Fri Aug 27 2021

PAC089-095-271910-
/O.CAN.KPHI.SV.W.0271.000000T0000Z-210827T1915Z/
Monroe PA-Northampton PA-
300 PM EDT Fri Aug 27 2021

...THE SEVERE THUNDERSTORM WARNING FOR SOUTH CENTRAL MONROE AND
CENTRAL NORTHAMPTON COUNTIES IS CANCELLED...
                
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 has been cancelled.

LAT...LON 4101 7512 4070 7521 4078 7549 4094 7547
TIME...MOT...LOC 1858Z 266DEG 2KT 4086 7530 

$$

Gorse

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 27, 1:20 PM EDTAreal Flood AdvisoryPHICarbon, Monroe2 hr
Aug 27, 1:33 PM EDTAreal Flood AdvisoryPHIBucks, Delaware, Philadelphia83 min
Aug 27, 1:36 PM EDTSpecial Weather StatementPHIMonroe24 min
Aug 27, 1:52 PM EDTSevere Thunderstorm WarningPHIChester53 min
Aug 27, 2:12 PM EDTSpecial Weather StatementPHINorthampton33 min
Aug 27, 2:18 PM EDTAreal Flood AdvisoryPHIChester93 min
Aug 27, 2:33 PM EDTAreal Flood AdvisoryPHICarbon, Monroe, Northampton109 min
Aug 27, 2:42 PM EDTSevere Thunderstorm WarningPHIChester14 min
Aug 27, 3:07 PM EDTSevere Thunderstorm WarningPHINorthampton24 min
Aug 27, 3:44 PM EDTSpecial Weather StatementPHIDelaware31 min
Aug 27, 5:29 PM EDTAreal Flood AdvisoryPHIBucks, Montgomery3 hr
Aug 27, 6:29 PM EDTAreal Flood AdvisoryPHIBerks3 hr
Aug 27, 6:41 PM EDTSpecial Weather StatementPHIBerks34 min
Aug 27, 7:17 PM EDTFlash Flood WarningPHIBerks3 hr

Nearby

Severe 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.