Alert archive / Maryland / Mesoscale Discussions in 2020

Mesoscale Discussion 106

February 7, 20205 states

The Storm Prediction Center issued this mesoscale discussion at Feb 7, 2020, 9:50 AM EST for 5 states. It was in force for 85 min.

The area

The outline as issued.

The facts

Issued: Feb 7, 2020, 9:50 AM EST (14:50 UTC)
Expired: Feb 7, 2020, 11:15 AM EST
In force: 85 min
Issued by: the Storm Prediction Center
Chance of a watch: 5%

All 21 counties

Kent County, DE, New Castle County, DE, Caroline County, MD, Cecil County, MD, Dorchester County, MD, Queen Anne's County, MD, Somerset County, MD, Talbot County, MD, Wicomico County, MD, Burlington County, NJ, Camden County, NJ, Cumberland County, NJ, Gloucester County, NJ, Salem County, NJ, Bucks County, PA, Chester County, PA, Delaware County, PA, Montgomery County, PA, Philadelphia County, PA, Accomack County, VA, Northampton County, VA

The radar

The Dover AFB radar (KDOX), 22 km from the middle of the area, began a volume at 14:53 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 12:00Z, 2.8 hours before the alert went out and 120 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 530 m above ground
0-6 km bulk shear: 147 kt
0-1 km storm-relative helicity: 1300 m²/s²
0-3 km storm-relative helicity: 1322 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

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.

Issued	Product	Office	Counties	Lasted
Feb 7, 6:56 AM EST	Mesoscale Discussion	SPC	Anne Arundel, Charles, Montgomery, Prince George's	64 min
Feb 6, 7:48 PM EST	Mesoscale Discussion	SPC	Crawford, Erie	4 hr
Feb 7, 5:32 AM EST	Mesoscale Discussion	SPC	Allegheny, Armstrong, Beaver, Butler, Cameron, Clarion and 12 more	3 hr

Nearby

Mesoscale Discussions in Maryland, 2020 Mesoscale Discussions in New Jersey, 2020 Mesoscale Discussions in Pennsylvania, 2020 Every mesoscale discussion in 2020

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.