Alert archive / Maryland / Mesoscale Discussions in 2003

Mesoscale Discussion 1642

July 6, 20037 states

The Storm Prediction Center issued this mesoscale discussion at Jul 6, 2003, 12:28 AM EDT for 7 states. It was in force for 2 hr.

The area

The outline as issued.

The facts

Issued: Jul 6, 2003, 12:28 AM EDT (04:28 UTC)
Expired: Jul 6, 2003, 2:30 AM EDT
In force: 2 hr
Issued by: the Storm Prediction Center

All 54 counties

Kent County, DE, New Castle County, DE, Allegany County, MD, Anne Arundel County, MD, Baltimore County, MD, Caroline County, MD, Carroll County, MD, Cecil County, MD, City of Baltimore, MD, Frederick County, MD, Garrett County, MD, Harford County, MD, Howard County, MD, Kent County, MD, Montgomery County, MD, Queen Anne's County, MD, Washington County, MD, Cape May County, NJ, Cumberland County, NJ, Salem County, NJ, Belmont County, OH, Coshocton County, OH, Guernsey County, OH, Licking County, OH, Monroe County, OH, Morgan County, OH, Muskingum County, OH, Noble County, OH, Perry County, OH, Adams County, PA, Bedford County, PA, Fayette County, PA, Franklin County, PA, Fulton County, PA, Greene County, PA, Somerset County, PA, Washington County, PA, City of Winchester, VA, Clarke County, VA, Frederick County, VA, Loudoun County, VA, Berkeley County, WV, Hampshire County, WV, Jefferson County, WV, Marion County, WV, Marshall County, WV, Mineral County, WV, Monongalia County, WV, Morgan County, WV, Ohio County, WV, Preston County, WV, Taylor County, WV, Tyler County, WV, Wetzel County, WV

The radar

The Pittsburgh radar (KPBZ), 107 km from the middle of the area, began a volume at 04:28 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

Pittsburgh, PA (KPIT), launched 00:00Z, 4.5 hours before the alert went out and 90 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: 29 J/kg
Mixed-layer CIN: -29 J/kg
Mixed-layer LCL: 1378 m above ground
0-6 km bulk shear: 28 kt
0-1 km storm-relative helicity: 85 m²/s²
0-3 km storm-relative helicity: 147 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.2

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
Jul 6, 1:04 PM EDT	Mesoscale Discussion	SPC	Kent, Sussex	2 hr
Jul 6, 7:23 PM EDT	Mesoscale Discussion	SPC	Kent, New Castle	67 min
Jul 6, 5:46 PM EDT	Mesoscale Discussion	SPC	Anne Arundel, Calvert, Charles, Montgomery, Prince George's, Saint Mary's	59 min
Jul 5, 8:20 PM EDT	Mesoscale Discussion	SPC	Butler, Clermont, Darke, Hamilton, Miami, Montgomery and 2 more	55 min
Jul 6, 1:36 PM EDT	Mesoscale Discussion	SPC	Defiance, Fulton, Henry, Lucas, Williams	114 min
Jul 6, 2:25 PM EDT	Severe Thunderstorm Watch	SPC	Defiance, Fulton, Henry, Lucas, Ottawa, Sandusky and 2 more	5 hr
Jul 6, 6:28 PM EDT	Mesoscale Discussion	SPC	Allen, Auglaize, Darke, Defiance, Fulton, Hancock and 10 more	62 min
Jul 6, 6:45 PM EDT	Severe Thunderstorm Watch	SPC	Allen, Auglaize, Champaign, Crawford, Darke, Defiance and 22 more	5 hr

Nearby

Mesoscale Discussions in Maryland, 2003 Mesoscale Discussions in West Virginia, 2003 Mesoscale Discussions in Ohio, 2003 Every mesoscale discussion in 2003

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.