Alert archive / Pennsylvania / Special Weather Statements in 2018

Special Weather Statement, NWS Philadelphia/Mount Holly

August 7, 2018Lehigh County, Pennsylvania

NWS Philadelphia/Mount Holly issued this special weather statement at Aug 7, 2018, 5:41 PM EDT for Lehigh County, Pennsylvania. It was in force for 49 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
Aug 7, 2018, 5:41 PM EDT (21:41 UTC)
Expired
Aug 7, 2018, 6:30 PM EDT
In force
49 min
Issued by
NWS Philadelphia/Mount Holly

County Lehigh County, PA

The radar

The Philadelphia radar (KDIX), 129 km from the middle of the area, began a volume at 21:43 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 12:00Z, 9.7 hours before the alert went out and 237 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, Washington/Dulle, VA at 12:00Z on 2018-08-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1323 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, Washington/Dulle, VA at 12:00Z on 2018-08-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 3 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
1323 J/kg
Mixed-layer CIN
-69 J/kg
Mixed-layer LCL
955 m above ground
0-6 km bulk shear
11 kt
0-1 km storm-relative helicity
3 m²/s²
0-3 km storm-relative helicity
48 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

331 
WWUS81 KPHI 072141
SPSPHI

Special Weather Statement
National Weather Service Mount Holly NJ
541 PM EDT TUE AUG 7 2018

PAZ060-061-072230-
Lehigh-Berks-
541 PM EDT TUE AUG 7 2018

...A STRONG THUNDERSTORM WILL AFFECT NORTHEASTERN BERKS AND LEHIGH 
COUNTIES...

At 540 PM EDT, a strong thunderstorm was located near Kutztown, 
moving east at 12 mph.

Winds up to 40 mph and half inch hail are possible with this storm.

Locations that may be impacted include... 

Allentown, Emmaus, Northampton, Kutztown, Topton, Lyons, Coffeetown, 
New Tripoli, Zionsville, Ancient Oaks, Schnecksville, Claussville, 
Coplay, Macungie, North Catasauqua, Alburtis, Fullerton and 
Hokendauqua.

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

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

LAT...LON 4069 7583 4068 7550 4067 7548 4044 7550
      4049 7585
TIME...MOT...LOC 2140Z 275DEG 10KT 4058 7579 

$$

Iovino

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 7, 12:19 PM EDTHeat AdvisoryPHIBurlington, Camden, Gloucester, Hunterdon, Mercer, Middlesex and 6 more6 hr
Aug 7, 2:24 PM EDTAreal Flood AdvisoryPHISussex78 min
Aug 7, 3:31 PM EDTHeat AdvisoryPHIBurlington, Camden, Gloucester, Hunterdon, Mercer, Middlesex and 4 more26 hr
Aug 7, 4:27 PM EDTSpecial Weather StatementPHISussex48 min
Aug 7, 5:07 PM EDTSpecial Weather StatementPHISussex53 min
Aug 7, 5:46 PM EDTSpecial Weather StatementPHIMorris, Sussex59 min
Aug 7, 4:07 PM EDTSpecial Weather StatementPHIMonroe38 min
Aug 7, 4:44 PM EDTSpecial Weather StatementPHIMonroe61 min
Aug 7, 4:48 PM EDTSpecial Weather StatementPHILehigh57 min
Aug 7, 5:32 PM EDTSpecial Weather StatementPHIBerks58 min
Aug 7, 6:21 PM EDTSpecial Weather StatementPHILehigh54 min
Aug 7, 6:25 PM EDTSpecial Weather StatementPHIBerks65 min
Aug 7, 2:13 PM EDTSpecial Weather StatementPHISussex47 min
Aug 7, 4:50 PM EDTSpecial Weather StatementPHIKent55 min

Nearby

Special Weather Statements in Pennsylvania, 2018Every special weather statement in 2018

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.