Alert archive / Pennsylvania / Special Weather Statements in 2018

Special Weather Statement, NWS Philadelphia/Mount Holly

August 2, 2018Lehigh County, Pennsylvania

NWS Philadelphia/Mount Holly issued this special weather statement at Aug 2, 2018, 1:50 PM EDT for Lehigh County, Pennsylvania. It was in force for 25 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 2, 2018, 1:50 PM EDT (17:50 UTC)
Expired
Aug 2, 2018, 2:15 PM EDT
In force
25 min
Issued by
NWS Philadelphia/Mount Holly

County Lehigh County, PA

The radar

The Philadelphia radar (KDIX), 114 km from the middle of the area, began a volume at 17:51 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, 5.8 hours before the alert went out and 221 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 2018-08-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 98 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 2018-08-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -23 square meters per square second.19395878Sfc1 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
98 J/kg
Mixed-layer CIN
-90 J/kg
Mixed-layer LCL
727 m above ground
0-6 km bulk shear
47 kt
0-1 km storm-relative helicity
-23 m²/s²
0-3 km storm-relative helicity
13 m²/s²
Significant tornado parameter
-0.0
Supercell composite
-0.0

Open this sounding in Storm Lab

The text

As transmitted.

950 
WWUS81 KPHI 021750
SPSPHI

Special Weather Statement
National Weather Service Mount Holly NJ
150 PM EDT THU AUG 2 2018

PAZ060>062-103-105-021815-
Upper Bucks-Lehigh-Western Montgomery-Northampton-Berks-
150 PM EDT THU AUG 2 2018

...A STRONG THUNDERSTORM WILL AFFECT SOUTHEASTERN BERKS...
NORTHWESTERN MONTGOMERY...SOUTHEASTERN LEHIGH...NORTHWESTERN BUCKS
AND SOUTHERN NORTHAMPTON COUNTIES...

At 149 PM EDT, a strong thunderstorm was located near Fleetwood, or 9
miles east of Reading, moving east at 40 mph.

Winds up to 50 mph are possible with this storm.

Locations impacted include...
Allentown, Bethlehem, Emmaus, Quakertown, Perkasie, Hellertown,
Birdsboro, Fleetwood, East Greenville, Bally, Bechtelsville, Green
Lane, Zionsville, Ancient Oaks, Lehigh University, Geryville,
Gilbertsville, Fountain Hill, Sellersville and Boyertown.

This storm may intensify, so be certain to monitor local radio and 
television stations, NOAA Weather Radio or social media, for 
additional information and possible warnings from the National 
Weather Service.

LAT...LON 4025 7581 4042 7589 4063 7536 4038 7523
TIME...MOT...LOC 1749Z 248DEG 34KT 4037 7576 

$$

Kruzdlo

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 1, 10:40 PM EDTSevere Thunderstorm WarningPHIHunterdon, Warren37 min
Aug 1, 11:35 PM EDTSevere Thunderstorm WarningPHISalem20 min
Aug 2, 3:31 AM EDTFlash Flood WatchPHIMorris, Sussex, Warren55 hr
Aug 2, 1:41 PM EDTSpecial Weather StatementPHIBurlington34 min
Aug 2, 2:09 PM EDTSpecial Weather StatementPHIMonmouth36 min
Aug 2, 3:41 PM EDTSpecial Weather StatementPHIMorris34 min
Aug 2, 6:02 PM EDTSpecial Marine WarningPHI58 min
Aug 1, 8:59 PM EDTSpecial Weather StatementPHIBerks61 min
Aug 1, 9:54 PM EDTSpecial Weather StatementPHIBerks, Carbon, Lehigh66 min
Aug 2, 2:19 PM EDTSpecial Weather StatementPHINorthampton41 min
Aug 1, 10:58 PM EDTSevere Thunderstorm WarningPHINew Castle47 min
Aug 2, 5:36 PM EDTSpecial Weather StatementPHINew Castle24 min
Aug 2, 5:40 PM EDTSpecial Weather StatementPHIKent35 min
Aug 2, 4:37 PM EDTSpecial Weather StatementPHIQueen Anne's23 min
Aug 2, 5:03 PM EDTSpecial Weather StatementPHIKent27 min
Aug 2, 5:34 PM EDTSpecial Weather StatementPHIQueen Anne's26 min
Aug 2, 6:07 PM EDTSpecial Weather StatementPHIKent, Queen Anne's38 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.