Alert archive / New Jersey / Mesoscale Discussions in 2011

Mesoscale Discussion 362

April 5, 201114 counties in New Jersey; 11 counties in Pennsylvania

The Storm Prediction Center issued this mesoscale discussion at Apr 5, 2011, 5:03 AM EDT for 14 counties in New Jersey; 11 counties in Pennsylvania. It was in force for 27 min.

The area

The outline as issued.

The facts

Issued
Apr 5, 2011, 5:03 AM EDT (09:03 UTC)
Expired
Apr 5, 2011, 5:30 AM EDT
In force
27 min
Issued by
the Storm Prediction Center
All 25 counties

Atlantic County, NJ, Burlington County, NJ, Camden County, NJ, Cape May County, NJ, Cumberland County, NJ, Gloucester County, NJ, Hunterdon County, NJ, Mercer County, NJ, Middlesex County, NJ, Monmouth County, NJ, Ocean County, NJ, Salem County, NJ, Somerset County, NJ, Warren County, NJ, Berks County, PA, Bucks County, PA, Carbon County, PA, Chester County, PA, Delaware County, PA, Lancaster County, PA, Lehigh County, PA, Monroe County, PA, Montgomery County, PA, Northampton County, PA, Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 74 km from the middle of the area, began a volume at 09:04 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

The nearest sounding before it

Brookhaven, NY (KOKX), launched 00:00Z, 9.1 hours before the alert went out and 220 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 00:00Z on 2011-04-05Temperature 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 00:00Z on 2011-04-05The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 240 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1278 m above ground
0-6 km bulk shear
57 kt
0-1 km storm-relative helicity
240 m²/s²
0-3 km storm-relative helicity
265 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

460 
ACUS11 KWNS 050904
SWOMCD
SPC MCD 050903
NJZ000-PAZ000-DEZ000-MDZ000-050930-

MESOSCALE DISCUSSION 0362
NWS STORM PREDICTION CENTER NORMAN OK
0403 AM CDT TUE APR 05 2011

AREAS AFFECTED...PORTIONS SERN PA...NJ.

CONCERNING...SEVERE POTENTIAL...WATCH NEEDED SOON

VALID 050903Z - 050930Z

WW ISSUANCE IS NECESSARY N OF WW 101...WHERE NRN END OF EXTENSIVE
SQUALL LINE WILL POSE THREAT OF DAMAGING GUSTS.  NARROW CORRIDOR OF
MRGLLY DESTABILIZING BOUNDARY LAYER AIR EXTENDS UP DE VALLEY FROM
DELMARVA REGION AMIDST FAVORABLY STG LOW-MIDLEVEL WIND
PROFILES...LEADING TO THREAT FOR MOMENTUM TRANSFER TO GROUND IN MOST
INTENSE DOWNDRAFTS.  SOME OF THIS AIR MASS MAY ADVECT CLOSER TO
COAST AND SHUNT STABLE MARINE AIR EWD SLIGHTLY...GIVEN POTENTIAL FOR
SOME VEERING OF BOUNDARY-LAYER FLOW IMMEDIATELY AHEAD OF QLCS.

..EDWARDS.. 04/05/2011

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...OKX...PHI...BGM...CTP...LWX...

LAT...LON   39737644 40897587 41177540 41167480 40717456 40227397
            39477435 38967498 39367539 39637560 39737644

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 5, 5:07 AM EDTSevere Thunderstorm WatchSPCAtlantic, Burlington, Camden, Cape May, Cumberland, Gloucester and 10 more2 hr
Apr 5, 6:25 AM EDTMesoscale DiscussionSPCAtlantic, Bergen, Burlington, Camden, Cape May, Cumberland and 14 more2 hr

Nearby

Mesoscale Discussions in New Jersey, 2011Mesoscale Discussions in Pennsylvania, 2011Every mesoscale discussion in 2011

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.