Alert archive / Pennsylvania / Severe Thunderstorm Warnings in 2009

Severe Thunderstorm Warning 99, NWS Philadelphia/Mount Holly

June 26, 2009Berks County, Pennsylvania

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at Jun 26, 2009, 6:30 PM EDT for Berks County, Pennsylvania. It was in force for 45 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued: Jun 26, 2009, 6:30 PM EDT (22:30 UTC)
Expired: Jun 26, 2009, 7:15 PM EDT
In force: 45 min
Issued by: NWS Philadelphia/Mount Holly
Area: Storm-based polygon

County Berks County, PA

The radar

The Philadelphia radar (KDIX), 133 km from the middle of the area, began a volume at 22:30 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 watch it was issued in

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

Issued	Product	Office	Lasted
Jun 26, 2:42 PM EDT	Severe Thunderstorm Watch	SPC	7 hr

The nearest sounding before it

Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 10.5 hours before the alert went out and 93 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: 1259 J/kg
Mixed-layer CIN: -73 J/kg
Mixed-layer LCL: 969 m above ground
0-6 km bulk shear: 24 kt
0-1 km storm-relative helicity: 29 m²/s²
0-3 km storm-relative helicity: 26 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.5

Open this sounding in Storm Lab

The text

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

000 
WUUS51 KPHI 262230
SVRPHI
PAC011-262315-
/O.NEW.KPHI.SV.W.0099.090626T2230Z-090626T2315Z/

BULLETIN - EAS ACTIVATION REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
630 PM EDT FRI JUN 26 2009

THE NATIONAL WEATHER SERVICE IN MOUNT HOLLY NJ HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHEASTERN BERKS COUNTY IN EASTERN PENNSYLVANIA...
  THIS INCLUDES THE CITY OF READING...

* UNTIL 715 PM EDT

* AT 631 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING NICKEL SIZE HAIL...AND
  DAMAGING WINDS IN EXCESS OF 60 MPH.  THIS STORM WAS LOCATED NEAR
  READING...AND MOVING EAST AT 25 MPH.

* THE SEVERE THUNDERSTORM WILL BE NEAR...
  BIRDSBORO AROUND 650 PM EDT...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IN ADDITION TO LARGE HAIL AND DAMAGING WINDS...CONTINUOUS CLOUD TO
GROUND LIGHTNING IS OCCURRING WITH THIS STORM. MOVE INDOORS
IMMEDIATELY LIGHTNING IS ONE OF NATURES NUMBER ONE KILLERS.
REMEMBER...IF YOU CAN HEAR THUNDER...YOU ARE CLOSE ENOUGH TO BE
STRUCK BY LIGHTNING.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 1000 PM EDT
FRIDAY EVENING FOR DELAWARE AND NORTHEASTERN MARYLAND AND NEW JERSEY
AND EASTERN PENNSYLVANIA.

&&

LAT...LON 4041 7605 4034 7562 4024 7570 4016 7584
      4021 7601 4026 7609
TIME...MOT...LOC 2231Z 290DEG 22KT 4030 7595

$$
SZATKOWSKI

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 26, 3:31 PM EDT	Severe Thunderstorm Warning	PHI	Monroe	59 min
Jun 26, 3:53 PM EDT	Severe Thunderstorm Warning	PHI	Carbon, Monroe	82 min
Jun 26, 4:51 PM EDT	Severe Thunderstorm Warning	PHI	Carbon, Monroe, Northampton	69 min
Jun 26, 5:35 PM EDT	Severe Thunderstorm Warning	PHI	Berks	55 min
Jun 26, 6:01 PM EDT	Severe Thunderstorm Warning	PHI	Bucks, Montgomery	59 min
Jun 26, 6:16 PM EDT	Severe Thunderstorm Warning	PHI	Bucks, Lehigh	59 min
Jun 26, 6:23 PM EDT	Severe Thunderstorm Warning	PHI	Chester, Montgomery	52 min
Jun 26, 6:41 PM EDT	Severe Thunderstorm Warning	PHI	Bucks	41 min
Jun 26, 6:57 PM EDT	Severe Thunderstorm Warning	PHI	Montgomery, Philadelphia	48 min
Jun 26, 7:10 PM EDT	Severe Thunderstorm Warning	PHI	Bucks, Montgomery, Philadelphia	50 min
Jun 26, 7:15 PM EDT	Severe Thunderstorm Warning	PHI	Chester, Delaware, Montgomery, Philadelphia	60 min
Jun 26, 7:28 PM EDT	Severe Thunderstorm Warning	PHI	Bucks, Montgomery, Philadelphia	92 min
Jun 26, 7:30 PM EDT	Severe Thunderstorm Warning	PHI	Berks	45 min
Jun 26, 7:45 PM EDT	Severe Thunderstorm Warning	PHI	Philadelphia	65 min

Nearby

Severe Thunderstorm Warnings in Pennsylvania, 2009 Every severe thunderstorm warning in 2009

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.