Alert archive / Pennsylvania / Special Weather Statements in 2021

Special Weather Statement, NWS Philadelphia/Mount Holly

September 8, 2021Lehigh County, Pennsylvania

NWS Philadelphia/Mount Holly issued this special weather statement at Sep 8, 2021, 9:12 PM EDT for Lehigh County, Pennsylvania. It was in force for 48 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: Sep 8, 2021, 9:12 PM EDT (01:12 UTC)
Expired: Sep 8, 2021, 10:00 PM EDT
In force: 48 min
Issued by: NWS Philadelphia/Mount Holly
Hail: 0.50 in
Wind: 40

County Lehigh County, PA

The radar

The Philadelphia radar (KDIX), 144 km from the middle of the area, began a volume at 01:15 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, 1.2 hours before the alert went out and 230 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: 1652 J/kg
Mixed-layer CIN: -18 J/kg
Mixed-layer LCL: 1146 m above ground
0-6 km bulk shear: 43 kt
0-1 km storm-relative helicity: 115 m²/s²
0-3 km storm-relative helicity: 136 m²/s²
Significant tornado parameter: 1.0
Supercell composite: 7.0

Open this sounding in Storm Lab

The text

As transmitted.

009 
WWUS81 KPHI 090112
SPSPHI

Special Weather Statement
National Weather Service Mount Holly NJ
912 PM EDT Wed Sep 8 2021
 
PAZ060-061-090200-
Lehigh PA-Berks PA-
912 PM EDT Wed Sep 8 2021

...A strong thunderstorm will impact portions of northeastern Berks
and central Lehigh Counties through 1000 PM EDT...

At 912 PM EDT, Doppler radar was tracking a strong thunderstorm over
Lenhartsville, or 14 miles east of Schuylkill Haven, moving east at
20 mph.

HAZARD...Wind gusts up to 45 mph and half inch hail.

SOURCE...Radar indicated.

IMPACT...Gusty winds could knock down tree limbs and blow around 
         unsecured objects. Minor damage to outdoor objects is 
         possible.

Locations impacted include...
Allentown, Lenhartsville, Jordan Valley, Neffs, Wanamakers,
Schnecksville, Coffeetown, New Tripoli, Claussville, Catasauqua,
Fullerton and Hokendauqua.

This includes the following highways...
 Northeast Extension between mile markers 57 and 65.
 Interstate 78 in Pennsylvania between mile markers 33 and 54.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

If outdoors, consider seeking shelter inside a building. 

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

A Severe Thunderstorm Watch remains in effect until midnight EDT for
eastern Pennsylvania.

&&

LAT...LON 4063 7600 4065 7598 4069 7587 4070 7583
      4075 7573 4063 7543 4056 7562 4054 7595
      4061 7600
TIME...MOT...LOC 0112Z 248DEG 18KT 4060 7591 

MAX HAIL SIZE...0.50 IN
MAX WIND GUST...40 MPH

$$

Staarmann

The office that day

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

Issued	Product	Office	Counties	Lasted
Sep 8, 9:16 PM EDT	Areal Flood Advisory	PHI	Warren	3 hr
Sep 8, 9:16 PM EDT	Special Weather Statement	PHI	Sussex, Warren	29 min
Sep 8, 9:43 PM EDT	Special Weather Statement	PHI	Sussex, Warren	47 min
Sep 8, 10:42 PM EDT	Flash Flood Warning	PHI	Warren	6 hr
Sep 8, 10:56 PM EDT	Special Weather Statement	PHI	Warren	34 min
Sep 8, 11:27 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Warren	48 min
Sep 8, 11:30 PM EDT	Areal Flood Advisory	PHI	Morris, Sussex	4 hr
Sep 9, 12:07 AM EDT	Special Weather Statement	PHI	Hunterdon, Somerset, Warren	23 min
Sep 9, 12:18 AM EDT	Special Marine Warning	PHI		57 min
Sep 9, 12:30 AM EDT	Special Weather Statement	PHI	Morris	30 min
Sep 9, 12:41 AM EDT	Special Marine Warning	PHI		52 min
Sep 9, 2:17 AM EDT	Special Weather Statement	PHI	Ocean	28 min
Sep 9, 2:46 AM EDT	Special Weather Statement	PHI	Atlantic	29 min
Sep 9, 3:14 AM EDT	Special Weather Statement	PHI	Atlantic	31 min
Sep 9, 3:30 AM EDT	Areal Flood Advisory	PHI	Atlantic, Burlington, Cape May, Cumberland	112 min
Sep 9, 4:28 AM EDT	Areal Flood Warning	PHI	Warren	4 hr
Sep 8, 8:47 PM EDT	Special Weather Statement	PHI	Northampton	28 min
Sep 8, 9:38 PM EDT	Special Weather Statement	PHI	Berks	52 min
Sep 8, 9:46 PM EDT	Special Weather Statement	PHI	Lehigh, Northampton	44 min
Sep 8, 9:48 PM EDT	Flash Flood Warning	PHI	Lehigh, Northampton	7 hr
Sep 8, 9:59 PM EDT	Areal Flood Advisory	PHI	Berks	3 hr
Sep 8, 10:11 PM EDT	Severe Thunderstorm Warning	PHI	Berks	49 min
Sep 8, 10:23 PM EDT	Tornado Warning	PHI	Berks	22 min
Sep 8, 10:27 PM EDT	Special Weather Statement	PHI	Northampton	33 min
Sep 8, 10:47 PM EDT	Areal Flood Advisory	PHI	Carbon, Monroe	3 hr
Sep 8, 10:47 PM EDT	Severe Thunderstorm Warning	PHI	Berks, Lehigh, Montgomery, Northampton	58 min
Sep 8, 11:35 PM EDT	Special Weather Statement	PHI	Chester, Delaware, Montgomery	40 min
Sep 9, 12:08 AM EDT	Special Weather Statement	PHI	Bucks, Delaware, Montgomery, Philadelphia	37 min
Sep 9, 4:26 AM EDT	Areal Flood Warning	PHI	Lehigh, Northampton	3 hr
Sep 9, 12:58 AM EDT	Special Weather Statement	PHI	New Castle	32 min
Sep 9, 1:12 AM EDT	Areal Flood Advisory	PHI	New Castle	62 min
Sep 9, 5:37 AM EDT	Areal Flood Advisory	PHI	Kent, New Castle, Sussex	3 hr

Nearby

Special Weather Statements in Pennsylvania, 2021 Every special weather statement 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.