Alert archive / Pennsylvania / Special Weather Statements in 2018

Special Weather Statement, NWS Philadelphia/Mount Holly

August 2, 2018Northampton County, Pennsylvania

NWS Philadelphia/Mount Holly issued this special weather statement at Aug 2, 2018, 2:19 PM EDT for Northampton County, Pennsylvania. It was in force for 41 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, 2:19 PM EDT (18:19 UTC)
Expired: Aug 2, 2018, 3:00 PM EDT
In force: 41 min
Issued by: NWS Philadelphia/Mount Holly

County Northampton County, PA

The radar

The Philadelphia radar (KDIX), 95 km from the middle of the area, began a volume at 18:19 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

Brookhaven, NY (KOKX), launched 12:00Z, 6.3 hours before the alert went out and 206 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: 1199 J/kg
Mixed-layer CIN: -39 J/kg
Mixed-layer LCL: 650 m above ground
0-6 km bulk shear: 46 kt
0-1 km storm-relative helicity: 49 m²/s²
0-3 km storm-relative helicity: 57 m²/s²
Significant tornado parameter: 0.3
Supercell composite: 1.8

Open this sounding in Storm Lab

The text

As transmitted.

845 
WWUS81 KPHI 021819
SPSPHI

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

NJZ007-009-PAZ061-062-103-105-021900-
Hunterdon-Warren-Upper Bucks-Lehigh-Western Montgomery-Northampton-
219 PM EDT THU AUG 2 2018

...A STRONG THUNDERSTORM WILL AFFECT WEST CENTRAL HUNTERDON...
SOUTHWESTERN WARREN...NORTH CENTRAL MONTGOMERY...SOUTHEASTERN
LEHIGH...NORTHWESTERN BUCKS AND SOUTHEASTERN NORTHAMPTON COUNTIES...

At 218 PM EDT, a strong thunderstorm was located over Zionsville, or
8 miles south of Allentown, moving east at 35 mph.

Winds up to 50 mph are possible with this storm.

Locations impacted include...
Allentown, Easton, Bethlehem, Emmaus, Quakertown, Wilson, Bedminster,
Hellertown, Tinicum, East Greenville, Alpha, Ferndale, Frenchtown,
West Easton, Milford, Bloomsbury, Riegelsville, Glendon, Pleasant
Valley and Revere.

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

LAT...LON 4047 7496 4036 7548 4041 7551 4055 7558
      4074 7507
TIME...MOT...LOC 1818Z 248DEG 32KT 4047 7546 

$$

Kruzdlo

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 1, 10:40 PM EDT	Severe Thunderstorm Warning	PHI	Hunterdon, Warren	37 min
Aug 1, 11:35 PM EDT	Severe Thunderstorm Warning	PHI	Salem	20 min
Aug 2, 3:31 AM EDT	Flash Flood Watch	PHI	Morris, Sussex, Warren	55 hr
Aug 2, 1:41 PM EDT	Special Weather Statement	PHI	Burlington	34 min
Aug 2, 2:09 PM EDT	Special Weather Statement	PHI	Monmouth	36 min
Aug 2, 3:41 PM EDT	Special Weather Statement	PHI	Morris	34 min
Aug 2, 6:02 PM EDT	Special Marine Warning	PHI		58 min
Aug 1, 8:59 PM EDT	Special Weather Statement	PHI	Berks	61 min
Aug 1, 9:54 PM EDT	Special Weather Statement	PHI	Berks, Carbon, Lehigh	66 min
Aug 2, 1:50 PM EDT	Special Weather Statement	PHI	Lehigh	25 min
Aug 1, 10:58 PM EDT	Severe Thunderstorm Warning	PHI	New Castle	47 min
Aug 2, 5:36 PM EDT	Special Weather Statement	PHI	New Castle	24 min
Aug 2, 5:40 PM EDT	Special Weather Statement	PHI	Kent	35 min
Aug 2, 4:37 PM EDT	Special Weather Statement	PHI	Queen Anne's	23 min
Aug 2, 5:03 PM EDT	Special Weather Statement	PHI	Kent	27 min
Aug 2, 5:34 PM EDT	Special Weather Statement	PHI	Queen Anne's	26 min
Aug 2, 6:07 PM EDT	Special Weather Statement	PHI	Kent, Queen Anne's	38 min

Nearby

Special Weather Statements in Pennsylvania, 2018 Every 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.