Alert archive / New Jersey / Mesoscale Discussions in 2015

Mesoscale Discussion 1603

August 4, 20157 states

The Storm Prediction Center issued this mesoscale discussion at Aug 4, 2015, 3:29 AM EDT for 7 states. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued: Aug 4, 2015, 3:29 AM EDT (07:29 UTC)
Expired: Aug 4, 2015, 6:30 AM EDT
In force: 3 hr
Issued by: the Storm Prediction Center
Chance of a watch: 5%

All 53 counties

New Castle County, DE, Baltimore County, MD, Carroll County, MD, Cecil County, MD, City of Baltimore, MD, Frederick County, MD, Harford County, MD, Howard County, MD, Kent County, MD, Montgomery County, MD, Washington County, MD, Bergen County, NJ, Burlington County, NJ, Camden County, NJ, Essex County, NJ, Gloucester County, NJ, Hudson County, NJ, Hunterdon County, NJ, Mercer County, NJ, Middlesex County, NJ, Monmouth County, NJ, Morris County, NJ, Ocean County, NJ, Passaic County, NJ, Salem County, NJ, Somerset County, NJ, Union County, NJ, Bronx County, NY, Kings County, NY, Nassau County, NY, New York County, NY, Queens County, NY, Richmond County, NY, Rockland County, NY, Westchester County, NY, Adams County, PA, Berks County, PA, Bucks County, PA, Chester County, PA, Delaware County, PA, Lancaster County, PA, Lehigh County, PA, Montgomery County, PA, Philadelphia County, PA, York County, PA, City of Winchester, VA, Clarke County, VA, Frederick County, VA, Loudoun County, VA, Shenandoah County, VA, Warren County, VA, Berkeley County, WV, Jefferson County, WV

The radar

The Philadelphia radar (KDIX), 112 km from the middle of the area, began a volume at 07:29 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 00:00Z, 7.5 hours before the alert went out and 194 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: 627 J/kg
Mixed-layer CIN: -33 J/kg
Mixed-layer LCL: 1863 m above ground
0-6 km bulk shear: 38 kt
0-1 km storm-relative helicity: 90 m²/s²
0-3 km storm-relative helicity: 156 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.9

Open this sounding in Storm Lab

The text

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

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 4, 5:59 AM EDT	Mesoscale Discussion	SPC		3 hr
Aug 4, 12:18 PM EDT	Severe Thunderstorm Watch	SPC	Northwest Hills Planning Region	8 hr
Aug 4, 6:49 PM EDT	Mesoscale Discussion	SPC		86 min
Aug 4, 3:48 PM EDT	Mesoscale Discussion	SPC	Kent, New Castle, Sussex	3 hr
Aug 4, 11:15 AM EDT	Mesoscale Discussion	SPC	Columbia, Dutchess, Rensselaer, Washington	3 hr
Aug 4, 2:21 PM EDT	Mesoscale Discussion	SPC	Columbia, Rensselaer, Washington	84 min

Nearby

Mesoscale Discussions in New Jersey, 2015 Mesoscale Discussions in Maryland, 2015 Mesoscale Discussions in Pennsylvania, 2015 Every mesoscale discussion in 2015

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.