Alert archive / Maryland / Mesoscale Discussions in 2012

Mesoscale Discussion 1505

July 19, 20125 states

The Storm Prediction Center issued this mesoscale discussion at Jul 19, 2012, 6:53 PM EDT for 5 states. It was in force for 97 min.

The area

The outline as issued.

The facts

Issued
Jul 19, 2012, 6:53 PM EDT (22:53 UTC)
Expired
Jul 19, 2012, 8:30 PM EDT
In force
97 min
Issued by
the Storm Prediction Center
Chance of a watch
40%
All 39 counties

Kent County, DE, New Castle County, DE, Sussex County, DE, Anne Arundel County, MD, Baltimore County, MD, Caroline County, MD, Carroll County, MD, Cecil County, MD, City of Baltimore, MD, Dorchester County, MD, Frederick County, MD, Harford County, MD, Howard County, MD, Kent County, MD, Montgomery County, MD, Prince George's County, MD, Queen Anne's County, MD, Talbot County, MD, Washington County, MD, Wicomico County, MD, Worcester County, MD, Cape May County, NJ, Cumberland County, NJ, Gloucester County, NJ, Salem County, NJ, Adams County, PA, Chester County, PA, Cumberland County, PA, Dauphin County, PA, Delaware County, PA, Franklin County, PA, Juniata County, PA, Lancaster County, PA, Lebanon County, PA, Perry County, PA, York County, PA, Berkeley County, WV, Jefferson County, WV, Morgan County, WV

The radar

The Dover AFB radar (KDOX), 103 km from the middle of the area, began a volume at 22:53 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

Phillips Aaf/Abe, MD (KAPG), launched 12:00Z, 10.9 hours before the alert went out and 20 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, Phillips Aaf/Abe, MD at 12:00Z on 2012-07-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 137 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, Phillips Aaf/Abe, MD at 12:00Z on 2012-07-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 53 square meters per square second.1939Sfc1 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
137 J/kg
Mixed-layer CIN
-137 J/kg
Mixed-layer LCL
1167 m above ground
0-6 km bulk shear
15 kt
0-1 km storm-relative helicity
53 m²/s²
0-3 km storm-relative helicity
86 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.

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SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 19, 2:20 PM EDTMesoscale DiscussionSPCLogan, McDowell, Mingo85 min
Jul 19, 3:40 PM EDTSevere Thunderstorm WatchSPCLogan, McDowell, Mercer, Mingo, Monroe, Raleigh and 2 more7 hr
Jul 19, 7:17 PM EDTMesoscale DiscussionSPCLogan, McDowell, Mercer, Mingo, Raleigh, Summers and 1 more88 min

Nearby

Mesoscale Discussions in Maryland, 2012Mesoscale Discussions in Pennsylvania, 2012Mesoscale Discussions in New Jersey, 2012Every mesoscale discussion in 2012

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.