Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2010

Severe Thunderstorm Warning 41, NWS Philadelphia/Mount Holly

May 27, 20104 counties in Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at May 27, 2010, 5:11 PM EDT for 4 counties in Pennsylvania. It was in force for 64 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: May 27, 2010, 5:11 PM EDT (21:11 UTC)
Expired: May 27, 2010, 6:15 PM EDT
In force: 64 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon

Counties Berks County, PA, Carbon County, PA, Lehigh County, PA, Northampton County, PA

The radar

The Philadelphia radar (KDIX), 134 km from the middle of the area, began a volume at 21:13 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

Time	Report	Where	Remark
May 27, 5:51 PM EDT	HAIL 0.88	Fogelsville, PA	PEA TO NICKEL SIZE HAIL REPORTED IN FOGELSVILLE.

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

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
May 27, 1:23 PM EDT	Severe Thunderstorm Watch	SPC	8 hr

The nearest sounding before it

Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 9.2 hours before the alert went out and 139 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 759 J/kg
Mixed-layer CIN: -227 J/kg
Mixed-layer LCL: 1358 m above ground
0-6 km bulk shear: 22 kt
0-1 km storm-relative helicity: -74 m²/s²
0-3 km storm-relative helicity: 53 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.2

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

654 
WUUS51 KPHI 272111
SVRPHI
PAC011-025-077-095-272215-
/O.NEW.KPHI.SV.W.0041.100527T2111Z-100527T2215Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
511 PM EDT THU MAY 27 2010

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  NORTHEASTERN BERKS COUNTY IN EASTERN PENNSYLVANIA...
  LEHIGH COUNTY IN EASTERN PENNSYLVANIA...
  THIS INCLUDES THE CITY OF ALLENTOWN...
  WEST CENTRAL NORTHAMPTON COUNTY IN EASTERN PENNSYLVANIA...
  SOUTH CENTRAL CARBON COUNTY IN NORTHEAST PENNSYLVANIA...

* UNTIL 615 PM EDT

* AT 509 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL.  THIS
  STORM WAS LOCATED NEAR JORDAN VALLEY...OR 8 MILES SOUTH OF
  LEHIGHTON...AND MOVING SOUTHEAST AT 15 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  8 MILES SOUTHWEST OF WALNUTPORT AROUND 520 PM EDT...
  NEFFS AROUND 530 PM EDT...
  SCHNECKSVILLE AROUND 535 PM EDT...
  CLAUSSVILLE AND COFFEETOWN AROUND 550 PM EDT...
  6 MILES NORTHEAST OF TOPTON AROUND 610 PM EDT...
  ANCIENT OAKS AND 7 MILES SOUTHWEST OF ALLENTOWN AROUND 615 PM
  EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IN ADDITION TO LARGE HAIL AND DAMAGING WINDS...HEAVY RAIN WILL OCCUR
WITH THESE STORMS AND CAUSE LOW-LYING AND POOR DRAINAGE FLOODING.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 900 PM EDT
THURSDAY EVENING FOR NORTHERN DELAWARE AND NORTHEASTERN MARYLAND AND
NEW JERSEY AND EASTERN PENNSYLVANIA.

&&

LAT...LON 4061 7539 4046 7571 4069 7588 4074 7578
      4077 7582 4083 7570
TIME...MOT...LOC 2111Z 327DEG 11KT 4071 7574

$$

PO

1 follow-up statement

235 
WWUS51 KPHI 272140
SVSPHI

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
540 PM EDT THU MAY 27 2010

PAC025-095-272150-
/O.CAN.KPHI.SV.W.0041.000000T0000Z-100527T2215Z/
NORTHAMPTON PA-CARBON PA-
540 PM EDT THU MAY 27 2010

...THE SEVERE THUNDERSTORM WARNING FOR SOUTH CENTRAL CARBON AND WEST
CENTRAL NORTHAMPTON COUNTIES IS CANCELLED...

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 900 PM EDT
THURSDAY EVENING FOR NORTHERN DELAWARE AND NORTHEASTERN MARYLAND AND
NEW JERSEY AND EASTERN PENNSYLVANIA.

LAT...LON 4062 7578 4066 7573 4071 7569 4073 7562
      4058 7545 4046 7571 4048 7572
TIME...MOT...LOC 2140Z 327DEG 11KT 4064 7568

$$

PAC011-077-272215-
/O.CON.KPHI.SV.W.0041.000000T0000Z-100527T2215Z/
BERKS PA-LEHIGH PA-
540 PM EDT THU MAY 27 2010

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 615 PM EDT
FOR CENTRAL LEHIGH AND NORTHEASTERN BERKS COUNTIES...

AT 539 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE
HAIL...AND DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS
LOCATED NEAR CLAUSSVILLE...OR 11 MILES WEST OF ALLENTOWN...MOVING
SOUTHEAST AT 15 MPH.

THE SEVERE THUNDERSTORM WILL BE NEAR...
  CLAUSSVILLE AND COFFEETOWN BY 550 PM EDT...
  ANCIENT OAKS...ALBURTIS...6 MILES NORTHEAST OF TOPTON AND 7 MILES
  SOUTHWEST OF ALLENTOWN BY 615 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...PREPARE
IMMEDIATELY FOR DAMAGING WINDS...DESTRUCTIVE HAIL...AND DEADLY CLOUD
TO GROUND LIGHTNING. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...
PREFERABLY INSIDE A STRONG BUILDING BUT AWAY FROM WINDOWS.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 900 PM EDT
THURSDAY EVENING FOR NORTHERN DELAWARE AND NORTHEASTERN MARYLAND AND
NEW JERSEY AND EASTERN PENNSYLVANIA.

&&

LAT...LON 4062 7578 4066 7573 4071 7569 4073 7562
      4058 7545 4046 7571 4048 7572
TIME...MOT...LOC 2140Z 327DEG 11KT 4064 7568

$$

PO

The office that day

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

Issued	Product	Office	Counties	Lasted
May 27, 2:00 PM EDT	Severe Thunderstorm Warning	PHI	Bucks, Monroe, Northampton	60 min
May 27, 2:30 PM EDT	Flash Flood Warning	PHI	Northampton	33 min
May 27, 2:45 PM EDT	Special Weather Statement	PHI	Chester	60 min
May 27, 3:19 PM EDT	Severe Thunderstorm Warning	PHI	Bucks, Northampton	41 min
May 27, 4:53 PM EDT	Special Weather Statement	PHI	Bucks, Montgomery	52 min
May 27, 5:36 PM EDT	Severe Thunderstorm Warning	PHI	Monroe, Northampton	54 min
May 27, 5:44 PM EDT	Special Weather Statement	PHI	Delaware, Montgomery	61 min
May 27, 5:53 PM EDT	Severe Thunderstorm Warning	PHI	Chester, Delaware, Montgomery	37 min
May 27, 6:05 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Bucks, Lehigh, Montgomery	25 min
May 27, 6:20 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Chester, Lehigh, Montgomery	55 min
May 27, 6:35 PM EDT	Special Weather Statement	PHI	Northampton	55 min
May 27, 7:12 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Chester, Delaware, Montgomery	48 min
May 27, 7:25 PM EDT	Special Weather Statement	PHI	Montgomery	65 min
May 27, 7:40 PM EDT	Special Weather Statement	PHI	Bucks	65 min
May 27, 7:44 PM EDT	Areal Flood Advisory	PHI	Berks, Chester, Montgomery	3 hr
May 27, 7:56 PM EDT	Severe Thunderstorm Warning	PHI	Chester, Delaware	34 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2010 Every severe thunderstorm warning in 2010

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.