Alert archive / Maryland / Mesoscale Discussions in 2007
Mesoscale Discussion 1694
The Storm Prediction Center issued this mesoscale discussion at Aug 9, 2007, 8:47 AM EDT for 12 counties in Maryland; 7 counties in Pennsylvania. It was in force for 58 min.
The area
The outline as issued.
The facts
- Issued
- Aug 9, 2007, 8:47 AM EDT (12:47 UTC)
- Expired
- Aug 9, 2007, 9:45 AM EDT
- In force
- 58 min
- Issued by
- the Storm Prediction Center
Counties Anne Arundel County, MD, 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, Queen Anne's County, MD, Washington County, MD, Adams County, PA, Bedford County, PA, Cumberland County, PA, Franklin County, PA, Fulton County, PA, Huntingdon County, PA, York County, PA
The radar
The Sterling radar (KLWX), 92 km from the middle of the area, began a volume at 12:47 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 watches that followed
Watches SPC issued over any of the same counties within four hours of this discussion.
The nearest sounding before it
Washington/Dulle, VA (KIAD), launched 12:00Z, 0.8 hours before the alert went out and 95 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.
- Mixed-layer CAPE
- 547 J/kg
- Mixed-layer CIN
- -121 J/kg
- Mixed-layer LCL
- 1213 m above ground
- 0-6 km bulk shear
- 20 kt
- 0-1 km storm-relative helicity
- 40 m²/s²
- 0-3 km storm-relative helicity
- 117 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 3.4
The text
As transmitted, in the capitals the NWS used until 2016.
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</html>SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 9, 9:47 AM EDT | Severe Thunderstorm Watch | SPC | Allegany, Anne Arundel, Baltimore, Carroll, Frederick, Harford and 5 more | 6 hr |
| Aug 9, 12:35 PM EDT | Mesoscale Discussion | SPC | Anne Arundel, Baltimore, Calvert, Caroline, Cecil, Dorchester and 11 more | 85 min |
| Aug 9, 12:48 PM EDT | Severe Thunderstorm Watch | SPC | Caroline, Cecil, Dorchester, Kent, Queen Anne's, Somerset and 3 more | 3 hr |
| Aug 9, 1:22 PM EDT | Severe Thunderstorm Watch | SPC | Garrett | 7 hr |
| Aug 9, 2:25 PM EDT | Mesoscale Discussion | SPC | Calvert, Charles, Dorchester, Saint Mary's, Somerset, Wicomico | 2 hr |
| Aug 9, 2:41 PM EDT | Mesoscale Discussion | SPC | Allegany, Anne Arundel, Calvert, Charles, Dorchester, Frederick and 9 more | 94 min |
| Aug 9, 7:23 PM EDT | Mesoscale Discussion | SPC | Allegany, Anne Arundel, Baltimore, Calvert, Caroline, Carroll and 16 more | 67 min |
| Aug 9, 11:54 AM EDT | Mesoscale Discussion | SPC | Allegheny, Beaver, Butler, Fayette, Greene, Lawrence and 3 more | 2 hr |
| Aug 9, 5:03 PM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Butler, Fayette, Greene and 4 more | 87 min |
Nearby
Mesoscale Discussions in Maryland, 2007Mesoscale Discussions in Pennsylvania, 2007Every mesoscale discussion in 2007
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.