Alert archive / Pennsylvania / Special Weather Statements in 2015

Special Weather Statement, NWS Philadelphia/Mount Holly

May 31, 2015Chester County, Pennsylvania

NWS Philadelphia/Mount Holly issued this special weather statement at May 31, 2015, 11:47 PM EDT for Chester County, Pennsylvania. It was in force for 58 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: May 31, 2015, 11:47 PM EDT (03:47 UTC)
Expired: Jun 1, 2015, 12:45 AM EDT
In force: 58 min
Issued by: NWS Philadelphia/Mount Holly

County Chester County, PA

The radar

The Dover AFB radar (KDOX), 131 km from the middle of the area, began a volume at 03:49 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

Washington/Dulle, VA (KIAD), launched 00:00Z, 3.8 hours before the alert went out and 160 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: 246 J/kg
Mixed-layer CIN: -43 J/kg
Mixed-layer LCL: 1706 m above ground
0-6 km bulk shear: 16 kt
0-1 km storm-relative helicity: 51 m²/s²
0-3 km storm-relative helicity: 104 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

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

219 
WWUS81 KPHI 010347
SPSPHI

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE MOUNT HOLLY NJ
1147 PM EDT SUN MAY 31 2015
 
MDZ008-PAZ060-101-103-010445-
CECIL-CECIL-WESTERN MONTGOMERY-BERKS-WESTERN CHESTER-
1147 PM EDT SUN MAY 31 2015

...A LINE OF STRONG THUNDERSTORMS WILL AFFECT NORTHWESTERN CECIL...
NORTHWESTERN MONTGOMERY...WESTERN CHESTER AND SOUTHEASTERN BERKS
COUNTIES...

AT 1145 PM EDT...A LINE OF STRONG THUNDERSTORMS WAS ALONG A LINE
EXTENDING FROM ROTHSVILLE TO NEAR SYKESVILLE...AND MOVING NORTHEAST
AT 40 MPH.

WINDS IN EXCESS OF 30 MPH ARE POSSIBLE WITH THESE STORMS.

THESE STORMS WILL BE NEAR...
  NEW MORGAN AROUND 1210 AM EDT.
  BIRDSBORO AROUND 1220 AM EDT.
  POTTSTOWN AROUND 1230 AM EDT.
  BECHTELSVILLE AND GILBERTSVILLE AROUND 1240 AM EDT.
  BALLY AROUND 1245 AM EDT.

OTHER LOCATIONS IMPACTED BY THESE STORMS INCLUDE LORANE...STOWE...
AMITY GARDENS...BOYERTOWN...ATGLEN...HALFWAY HOUSE...FLYING HILLS...
CHRISTIANA...SOUTH POTTSTOWN AND REIFFTON.

BRIEF TORRENTIAL RAINFALL IS ALSO OCCURRING WITH SOME OF THESE 
STORMS...AND MAY CAUSE LOCALIZED FLOODING. DO NOT DRIVE YOUR VEHICLE 
THROUGH FLOODED ROADWAYS.

CLOUD TO GROUND LIGHTNING IS OCCURRING WITH SOME OF THESE STORM. 
LIGHTNING CAN STRIKE 15 MILES AWAY FROM A THUNDERSTORM. SEEK A SAFE 
SHELTER INSIDE A BUILDING OR VEHICLE.

LAT...LON 3973 7612 3988 7599 3995 7600 4004 7593
      4011 7594 4014 7588 4024 7603 4043 7552
      3974 7609 3974 7611 3966 7616 3966 7618
      3972 7623
TIME...MOT...LOC 0345Z 241DEG 36KT 4013 7626 3932 7699 
$$

DRAG

The office that day

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

Issued	Product	Office	Counties	Lasted
May 31, 8:13 PM EDT	Flash Flood Warning	PHI	Somerset	5 hr
May 31, 8:43 PM EDT	Special Weather Statement	PHI	Hunterdon	62 min
May 31, 9:06 PM EDT	Flash Flood Warning	PHI	Hunterdon	5 hr
Jun 1, 1:57 AM EDT	Areal Flood Advisory	PHI	Hunterdon, Middlesex, Morris, Somerset, Warren	3 hr
Jun 1, 2:17 AM EDT	Special Weather Statement	PHI	Camden, Gloucester, Mercer, Salem	43 min
Jun 1, 2:55 AM EDT	Areal Flood Advisory	PHI	Burlington, Camden, Gloucester, Mercer	2 hr
Jun 1, 3:20 AM EDT	Areal Flood Advisory	PHI	Mercer, Middlesex, Monmouth, Somerset	115 min
Jun 1, 3:35 AM EDT	Special Weather Statement	PHI	Atlantic, Monmouth, Ocean	25 min
Jun 1, 4:20 AM EDT	Flash Flood Watch	PHI	Atlantic, Burlington, Camden, Cape May, Cumberland, Gloucester and 8 more	26 hr
Jun 1, 5:56 AM EDT	Areal Flood Advisory	PHI	Burlington, Camden, Gloucester	3 hr
Jun 1, 10:05 AM EDT	Areal Flood Advisory	PHI	Middlesex, Somerset	4 hr
Jun 1, 10:11 AM EDT	Small Craft Advisory	PHI		4 days
Jun 1, 2:28 PM EDT	Special Weather Statement	PHI	Burlington, Camden, Cumberland, Gloucester, Salem	32 min
Jun 1, 3:04 PM EDT	Severe Thunderstorm Warning	PHI	Atlantic, Burlington, Camden, Gloucester	56 min
Jun 1, 3:29 PM EDT	Severe Thunderstorm Warning	PHI	Atlantic, Burlington	46 min
Jun 1, 3:42 PM EDT	Flash Flood Warning	PHI	Atlantic, Burlington, Camden, Cumberland, Gloucester, Salem	6 hr
Jun 1, 3:56 PM EDT	Special Weather Statement	PHI	Atlantic, Cape May	79 min
Jun 1, 4:26 PM EDT	Areal Flood Advisory	PHI	Atlantic, Burlington, Cape May, Ocean	3 hr
Jun 1, 4:32 PM EDT	Severe Thunderstorm Warning	PHI	Cumberland, Gloucester, Salem	43 min
Jun 1, 4:37 PM EDT	Tornado Warning	PHI	Salem	23 min
Jun 1, 5:27 PM EDT	Areal Flood Advisory	PHI	Cumberland, Gloucester, Salem	3 hr
Jun 1, 5:34 PM EDT	Areal Flood Advisory	PHI	Cape May	3 hr
Jun 1, 7:18 PM EDT	Flash Flood Warning	PHI	Cumberland	3 hr
Jun 1, 7:26 PM EDT	Special Marine Warning	PHI		34 min
Jun 1, 7:54 PM EDT	Special Weather Statement	PHI	Atlantic, Cape May	111 min
May 31, 9:44 PM EDT	Areal Flood Advisory	PHI	Bucks	5 hr
May 31, 11:10 PM EDT	Special Weather Statement	PHI	Lebanon	65 min
May 31, 11:59 PM EDT	Special Weather Statement	PHI	Berks	31 min
Jun 1, 12:14 AM EDT	Special Weather Statement	PHI	Chester	31 min
Jun 1, 12:21 AM EDT	Areal Flood Advisory	PHI	Berks, Chester, Lehigh, Montgomery	114 min
Jun 1, 12:44 AM EDT	Special Weather Statement	PHI	Chester, Montgomery	46 min
Jun 1, 1:28 AM EDT	Special Weather Statement	PHI	Bucks, Delaware, Montgomery, Philadelphia	47 min
Jun 1, 2:14 PM EDT	Special Weather Statement	PHI	Chester	61 min
Jun 1, 2:43 PM EDT	Severe Thunderstorm Warning	PHI	Chester	32 min
Jun 1, 4:55 PM EDT	Areal Flood Advisory	PHI	Delaware, Montgomery, Philadelphia	3 hr
Jun 1, 3:13 AM EDT	Areal Flood Advisory	PHI	Cecil, Kent	3 hr
Jun 1, 5:35 PM EDT	Severe Thunderstorm Warning	PHI	Cecil, Kent, Queen Anne's	70 min
Jun 1, 5:56 PM EDT	Areal Flood Advisory	PHI	Cecil, Kent, Queen Anne's	6 hr
Jun 1, 6:29 PM EDT	Flash Flood Warning	PHI	Cecil	3 hr
Jun 1, 6:53 PM EDT	Severe Thunderstorm Warning	PHI	Kent, Queen Anne's	37 min
Jun 1, 4:35 PM EDT	Flash Flood Warning	PHI	New Castle	3 hr
Jun 1, 6:11 PM EDT	Areal Flood Advisory	PHI	Kent, New Castle	6 hr

Nearby

Special Weather Statements in Pennsylvania, 2015 Every special weather statement in 2015

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.