Alert archive / New Jersey / Mesoscale Discussions in 2019

Mesoscale Discussion 413

April 19, 20194 states

The Storm Prediction Center issued this mesoscale discussion at Apr 19, 2019, 8:29 PM EDT for 4 states. It was in force for 91 min.

The area

The outline as issued.

The facts

Issued
Apr 19, 2019, 8:29 PM EDT (00:29 UTC)
Expired
Apr 19, 2019, 10:00 PM EDT
In force
91 min
Issued by
the Storm Prediction Center
Chance of a watch
40%

Counties Kent County, DE, New Castle County, DE, Sussex County, DE, Caroline County, MD, Wicomico County, MD, Camden County, NJ, Cumberland County, NJ, Gloucester County, NJ, Salem County, NJ, Delaware County, PA

The radar

The Dover AFB radar (KDOX), 49 km from the middle of the area, began a volume at 00:28 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

Wallops Is Stn, VA (KWAL), launched 00:00Z, 0.5 hours before the alert went out and 142 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, Wallops Is Stn, VA at 00:00Z on 2019-04-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 106 joules per kilogram.LCLLFCEL10008507005003002001001 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, Wallops Is Stn, VA at 00:00Z on 2019-04-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 358 square meters per square second.1939587897Sfc1 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
106 J/kg
Mixed-layer CIN
-74 J/kg
Mixed-layer LCL
669 m above ground
0-6 km bulk shear
51 kt
0-1 km storm-relative helicity
358 m²/s²
0-3 km storm-relative helicity
377 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.3

Open this sounding in Storm Lab

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 19, 8:54 PM EDTMesoscale DiscussionSPCAdams, Cumberland, Dauphin, Franklin, Juniata, Lancaster and 6 more96 min

Nearby

Mesoscale Discussions in New Jersey, 2019Mesoscale Discussions in Delaware, 2019Mesoscale Discussions in Maryland, 2019Every mesoscale discussion in 2019

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.