Alert archive / New Jersey / Severe Thunderstorm Watches in 2003

Severe Thunderstorm Watch 792

July 21, 200311 counties in New Jersey; 10 counties in New York; 5 counties in Pennsylvania

The Storm Prediction Center issued this severe thunderstorm watch at Jul 21, 2003, 6:30 PM EDT for 11 counties in New Jersey; 10 counties in New York; 5 counties in Pennsylvania. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
Jul 21, 2003, 6:30 PM EDT (22:30 UTC)
Expired
Jul 21, 2003, 11:00 PM EDT
In force
5 hr
Issued by
the Storm Prediction Center
All 26 counties

Bergen County, NJ, Essex County, NJ, Hudson County, NJ, Hunterdon County, NJ, Middlesex County, NJ, Morris County, NJ, Passaic County, NJ, Somerset County, NJ, Sussex County, NJ, Union County, NJ, Warren County, NJ, Bronx County, NY, Kings County, NY, Nassau County, NY, New York County, NY, Orange County, NY, Putnam County, NY, Queens County, NY, Richmond County, NY, Rockland County, NY, Westchester County, NY, Bucks County, PA, Lehigh County, PA, Monroe County, PA, Northampton County, PA, Pike County, PA

The radar

The Philadelphia radar (KDIX), 124 km from the middle of the area, began a volume at 22:33 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.

Warnings issued inside it

11 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Jul 21, 6:43 PM EDTSevere Thunderstorm WarningBGMPike62 min
Jul 21, 6:44 PM EDTSevere Thunderstorm WarningBGMPike61 min
Jul 21, 7:07 PM EDTSevere Thunderstorm WarningPHIBerks, Lehigh, Northampton53 min
Jul 21, 7:12 PM EDTSevere Thunderstorm WarningOKXOrange78 min
Jul 21, 7:12 PM EDTSevere Thunderstorm WarningPHIMonroe48 min
Jul 21, 7:26 PM EDTSevere Thunderstorm WarningPHISussex, Warren79 min
Jul 21, 7:46 PM EDTSevere Thunderstorm WarningOKXPassaic44 min
Jul 21, 7:54 PM EDTSevere Thunderstorm WarningPHIBerks, Lehigh, Northampton81 min
Jul 21, 8:07 PM EDTSevere Thunderstorm WarningPHIMorris83 min
Jul 21, 8:36 PM EDTSevere Thunderstorm WarningPHIHunterdon84 min
Jul 21, 9:01 PM EDTSevere Thunderstorm WarningPHISomerset89 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 10.5 hours before the alert went out and 150 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, Brookhaven, NY at 12:00Z on 2003-07-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Brookhaven, NY at 12:00Z on 2003-07-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 113 square meters per square second.193958Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1382 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
113 m²/s²
0-3 km storm-relative helicity
148 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 21, 3:35 PM EDTSevere Thunderstorm WatchSPC6 hr
Jul 21, 7:51 PM EDTMesoscale DiscussionSPC84 min
Jul 21, 1:15 PM EDTMesoscale DiscussionSPCAllegany, Broome, Cattaraugus, Chemung, Schuyler, Steuben and 2 more2 hr
Jul 21, 1:40 PM EDTSevere Thunderstorm WatchSPCAllegany, Broome, Chemung, Cortland, Schuyler, Steuben and 2 more6 hr
Jul 21, 2:46 PM EDTMesoscale DiscussionSPCAlbany, Columbia, Delaware, Greene, Montgomery, Otsego and 5 more119 min
Jul 21, 3:51 PM EDTMesoscale DiscussionSPCAllegany, Broome, Chemung, Cortland, Schuyler, Steuben and 2 more114 min
Jul 21, 8:40 AM EDTSevere Thunderstorm WatchSPCAllegheny, Armstrong, Beaver, Butler, Clarion, Greene and 4 more5 hr

Nearby

Severe Thunderstorm Watches in New Jersey, 2003Severe Thunderstorm Watches in New York, 2003Severe Thunderstorm Watches in Pennsylvania, 2003Every severe thunderstorm watch in 2003

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.