Alert archive / Maryland / Severe Thunderstorm Watches in 2003
Severe Thunderstorm Watch 911
The Storm Prediction Center issued this severe thunderstorm watch at Aug 29, 2003, 3:50 PM EDT for 5 states. It was in force for 5 hr.
The area
The outline as issued.
The facts
- Issued
- Aug 29, 2003, 3:50 PM EDT (19:50 UTC)
- Expired
- Aug 29, 2003, 9:00 PM EDT
- In force
- 5 hr
- Issued by
- the Storm Prediction Center
All 43 counties
New Castle County, DE, Anne Arundel County, MD, Baltimore County, MD, Calvert 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, Prince George's County, MD, Queen Anne's County, MD, Talbot County, MD, Camden County, NJ, Gloucester County, NJ, Mercer County, NJ, Middlesex County, NJ, Salem County, NJ, Berks County, PA, Bucks County, PA, Chester County, PA, Delaware County, PA, Lancaster County, PA, Lebanon County, PA, Montgomery County, PA, Philadelphia County, PA, York County, PA, Arlington County, VA, City of Alexandria, VA, City of Fairfax, VA, City of Falls Church, VA, City of Manassas, VA, City of Manassas Park, VA, Clarke County, VA, Fairfax County, VA, Fauquier County, VA, Loudoun County, VA, Page County, VA, Prince William County, VA, Rappahannock County, VA, Warren County, VA
The radar
The Sterling radar (KLWX), 70 km from the middle of the area, began a volume at 19:54 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.
Warnings issued inside it
1 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 29, 5:06 PM EDT | Flash Flood Warning | LWX | Fauquier | 3 hr |
Discussions around it
SPC mesoscale discussions over the same counties from four hours before the watch to its end.
The nearest sounding before it
Washington/Dulle, VA (KIAD), launched 12:00Z, 7.8 hours before the alert went out and 66 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
- 1493 J/kg
- Mixed-layer CIN
- -109 J/kg
- Mixed-layer LCL
- 677 m above ground
- 0-6 km bulk shear
- 23 kt
- 0-1 km storm-relative helicity
- 123 m²/s²
- 0-3 km storm-relative helicity
- 110 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 2.1
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 29, 2:59 PM EDT | Mesoscale Discussion | SPC | Kent, New Castle | 3 hr |
| Aug 29, 7:29 PM EDT | Mesoscale Discussion | SPC | Kent, New Castle, Sussex | 61 min |
| Aug 29, 1:32 PM EDT | Mesoscale Discussion | SPC | Allegheny, Armstrong, Beaver, Blair, Bradford, Butler and 26 more | 2 hr |
| Aug 29, 2:05 PM EDT | Severe Thunderstorm Watch | SPC | Armstrong, Beaver, Butler, Cameron, Centre, Clarion and 14 more | 5 hr |
| Aug 29, 4:51 PM EDT | Mesoscale Discussion | SPC | Armstrong, Beaver, Butler, Cameron, Centre, Clarion and 12 more | 84 min |
Nearby
Severe Thunderstorm Watches in Maryland, 2003Severe Thunderstorm Watches in Virginia, 2003Severe Thunderstorm Watches in Pennsylvania, 2003Every severe thunderstorm watch 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.