Alert archive / Virginia / Mesoscale Discussions in 2018
Mesoscale Discussion 1172
The Storm Prediction Center issued this mesoscale discussion at Jul 27, 2018, 1:28 PM EDT for 6 counties in Maryland; 44 counties in Virginia; 27 counties in West Virginia. It was in force for 62 min.
The area
The outline as issued.
The facts
- Issued
- Jul 27, 2018, 1:28 PM EDT (17:28 UTC)
- Expired
- Jul 27, 2018, 2:30 PM EDT
- In force
- 62 min
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 80%
All 77 counties
Anne Arundel County, MD, Charles County, MD, Frederick County, MD, Howard County, MD, Montgomery County, MD, Prince George's County, MD, Albemarle County, VA, Alleghany County, VA, Amherst County, VA, Arlington County, VA, Augusta County, VA, Bath County, VA, Botetourt County, VA, City of Alexandria, VA, City of Buena Vista, VA, City of Charlottesville, VA, City of Covington, VA, City of Fairfax, VA, City of Falls Church, VA, City of Fredericksburg, VA, City of Harrisonburg, VA, City of Lexington, VA, City of Manassas, VA, City of Manassas Park, VA, City of Staunton, VA, City of Waynesboro, VA, City of Winchester, VA, Clarke County, VA, Culpeper County, VA, Fairfax County, VA, Fauquier County, VA, Fluvanna County, VA, Frederick County, VA, Greene County, VA, Highland County, VA, King George County, VA, Loudoun County, VA, Louisa County, VA, Madison County, VA, Nelson County, VA, Orange County, VA, Page County, VA, Prince William County, VA, Rappahannock County, VA, Rockbridge County, VA, Rockingham County, VA, Shenandoah County, VA, Spotsylvania County, VA, Stafford County, VA, Warren County, VA, Barbour County, WV, Berkeley County, WV, Boone County, WV, Braxton County, WV, Clay County, WV, Fayette County, WV, Gilmer County, WV, Grant County, WV, Greenbrier County, WV, Hampshire County, WV, Hardy County, WV, Jefferson County, WV, Kanawha County, WV, Lewis County, WV, Lincoln County, WV, Logan County, WV, Mineral County, WV, Morgan County, WV, Nicholas County, WV, Pendleton County, WV, Pocahontas County, WV, Raleigh County, WV, Randolph County, WV, Summers County, WV, Tucker County, WV, Upshur County, WV, Webster County, WV
The radar
The Sterling radar (KLWX), 161 km from the middle of the area, began a volume at 17:29 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
Roanoke, VA (KRNK), launched 12:00Z, 5.5 hours before the alert went out and 156 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
- 83 J/kg
- Mixed-layer CIN
- -55 J/kg
- Mixed-layer LCL
- 1029 m above ground
- 0-6 km bulk shear
- 38 kt
- 0-1 km storm-relative helicity
- 17 m²/s²
- 0-3 km storm-relative helicity
- 72 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
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</html>SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 27, 1:17 PM EDT | Severe Thunderstorm Watch | SPC | Caroline, Cecil, Kent, Queen Anne's, Talbot | 9 hr |
| Jul 27, 1:52 PM EDT | Severe Thunderstorm Watch | SPC | Allegany, Anne Arundel, Baltimore, Calvert, Carroll, Charles and 12 more | 7 hr |
| Jul 27, 4:50 PM EDT | Mesoscale Discussion | SPC | Anne Arundel, Baltimore, Calvert, Caroline, Carroll, Cecil and 13 more | 55 min |
| Jul 27, 7:06 PM EDT | Mesoscale Discussion | SPC | Anne Arundel, Baltimore, Calvert, Caroline, Cecil, Charles and 13 more | 54 min |
Nearby
Mesoscale Discussions in Virginia, 2018Mesoscale Discussions in West Virginia, 2018Mesoscale Discussions in Maryland, 2018Every mesoscale discussion in 2018
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.