Alert archive / Virginia / Severe Thunderstorm Watches in 2016
Severe Thunderstorm Watch 396
The Storm Prediction Center issued this severe thunderstorm watch at Jul 18, 2016, 1:42 PM EDT for 6 states. It was in force for 6 hr.
The area
The outline as issued.
The facts
- Issued
- Jul 18, 2016, 1:42 PM EDT (17:42 UTC)
- Expired
- Jul 18, 2016, 8:00 PM EDT
- In force
- 6 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1.5 in
- Strongest gust expected
- 60 kt
All 80 counties
Kent County, DE, New Castle County, DE, Sussex County, DE, Anne Arundel County, MD, Baltimore County, MD, Calvert County, MD, Caroline County, MD, Carroll County, MD, Cecil County, MD, Charles 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, Saint Mary's County, MD, Somerset County, MD, Talbot County, MD, Washington County, MD, Wicomico County, MD, Worcester County, MD, Atlantic County, NJ, Burlington County, NJ, Camden County, NJ, Cape May County, NJ, Cumberland County, NJ, Gloucester County, NJ, Ocean County, NJ, Salem County, NJ, Adams County, PA, Berks County, PA, Bucks County, PA, Chester County, PA, Cumberland County, PA, Dauphin County, PA, Delaware County, PA, Franklin County, PA, Lancaster County, PA, Lebanon County, PA, Montgomery County, PA, Perry County, PA, Philadelphia County, PA, Schuylkill County, PA, York County, PA, Arlington County, VA, City of Alexandria, VA, City of Fairfax, VA, City of Falls Church, VA, City of Fredericksburg, VA, City of Harrisonburg, VA, City of Manassas, VA, City of Manassas Park, VA, City of Winchester, VA, Clarke County, VA, Culpeper County, VA, Fairfax County, VA, Fauquier County, VA, Frederick County, VA, Greene County, VA, King George County, VA, Loudoun County, VA, Madison County, VA, Orange County, VA, Page County, VA, Prince William County, VA, Rappahannock County, VA, Rockingham County, VA, Shenandoah County, VA, Spotsylvania County, VA, Stafford County, VA, Warren County, VA, Berkeley County, WV, Hampshire County, WV, Hardy County, WV, Jefferson County, WV, Morgan County, WV
The radar
The Sterling radar (KLWX), 119 km from the middle of the area, began a volume at 17:45 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.
What SPC expected
The probabilities SPC published with the watch, for the watch area over its life.
- Two or more tornadoes
- 10%
- One or more EF2 to EF5 tornadoes
- 2%
- Ten or more severe wind reports
- 50%
- One or more gusts of 65 knots or more
- 10%
- Ten or more severe hail reports
- 30%
- One or more hailstones of 2 inches or more
- 5%
- Six or more combined severe hail and wind reports
- 70%
Warnings issued inside it
23 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 18, 1:53 PM EDT | Severe Thunderstorm Warning | LWX | Allegany, Washington | 37 min |
| Jul 18, 2:23 PM EDT | Severe Thunderstorm Warning | LWX | Frederick, Washington | 52 min |
| Jul 18, 2:31 PM EDT | Severe Thunderstorm Warning | LWX | Fauquier, Madison, Page, Rappahannock, Rockingham, Shenandoah and 1 more | 44 min |
| Jul 18, 2:51 PM EDT | Severe Thunderstorm Warning | PHI | Berks, Bucks, Lehigh, Montgomery, Northampton | 39 min |
| Jul 18, 3:01 PM EDT | Severe Thunderstorm Warning | LWX | Clarke, Fauquier, Loudoun, Prince William, Warren | 27 min |
| Jul 18, 3:07 PM EDT | Severe Thunderstorm Warning | LWX | Culpeper, Fauquier, Madison, Rappahannock | 38 min |
| Jul 18, 3:25 PM EDT | Severe Thunderstorm Warning | PHI | Bucks | 50 min |
| Jul 18, 3:27 PM EDT | Severe Thunderstorm Warning | LWX | Montgomery | 18 min |
| Jul 18, 3:30 PM EDT | Severe Thunderstorm Warning | LWX | Culpeper, Fauquier, Orange, Prince William, Spotsylvania, Stafford | 45 min |
| Jul 18, 3:38 PM EDT | Severe Thunderstorm Warning | LWX | Baltimore, Carroll, Harford | 52 min |
| Jul 18, 3:41 PM EDT | Severe Thunderstorm Warning | PHI | Burlington, Camden, Gloucester | 49 min |
| Jul 18, 3:45 PM EDT | Severe Thunderstorm Warning | LWX | Montgomery | 45 min |
| Jul 18, 4:05 PM EDT | Severe Thunderstorm Warning | LWX | Charles, Prince George's | 40 min |
| Jul 18, 4:08 PM EDT | Severe Thunderstorm Warning | LWX | Anne Arundel, Calvert, Charles, Howard, Montgomery, Prince George's | 82 min |
| Jul 18, 4:14 PM EDT | Severe Thunderstorm Warning | PHI | New Castle | 46 min |
| Jul 18, 4:30 PM EDT | Severe Thunderstorm Warning | LWX | Culpeper, Greene, Madison, Orange | 45 min |
| Jul 18, 4:37 PM EDT | Severe Thunderstorm Warning | PHI | Kent, New Castle | 38 min |
| Jul 18, 5:18 PM EDT | Severe Thunderstorm Warning | PHI | Kent, New Castle | 57 min |
| Jul 18, 5:28 PM EDT | Severe Thunderstorm Warning | LWX | Orange, Spotsylvania | 47 min |
| Jul 18, 5:49 PM EDT | Severe Thunderstorm Warning | LWX | Saint Mary's | 15 min |
| Jul 18, 5:51 PM EDT | Severe Thunderstorm Warning | PHI | Ocean | 24 min |
| Jul 18, 6:24 PM EDT | Severe Thunderstorm Warning | AKQ | Somerset | 40 min |
| Jul 18, 6:35 PM EDT | Severe Thunderstorm Warning | AKQ | Somerset, Wicomico, Worcester | 40 min |
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, 5.7 hours before the alert went out and 117 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
- 200 J/kg
- Mixed-layer CIN
- -105 J/kg
- Mixed-layer LCL
- 1480 m above ground
- 0-6 km bulk shear
- 22 kt
- 0-1 km storm-relative helicity
- 4 m²/s²
- 0-3 km storm-relative helicity
- 18 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 18, 11:40 AM EDT | Mesoscale Discussion | SPC | New Castle | 95 min |
| Jul 18, 3:09 PM EDT | Mesoscale Discussion | SPC | Kent, New Castle, Sussex | 66 min |
| Jul 18, 6:22 PM EDT | Mesoscale Discussion | SPC | Sussex | 113 min |
| Jul 18, 12:05 PM EDT | Severe Thunderstorm Watch | SPC | Bergen, Essex, Hudson, Hunterdon, Mercer, Middlesex and 7 more | 8 hr |
| Jul 18, 3:21 PM EDT | Mesoscale Discussion | SPC | Bergen, Essex, Hudson, Hunterdon, Mercer, Middlesex and 7 more | 84 min |
| Jul 18, 6:49 PM EDT | Mesoscale Discussion | SPC | Bergen, Essex, Hudson, Hunterdon, Middlesex, Morris and 5 more | 86 min |
| Jul 18, 10:32 AM EDT | Mesoscale Discussion | SPC | Clinton, Essex, Franklin, Hamilton, Herkimer, Lewis and 3 more | 118 min |
| Jul 18, 11:12 AM EDT | Severe Thunderstorm Watch | SPC | Clinton, Essex, Franklin, Jefferson, Lewis, Oswego and 1 more | 9 hr |
Nearby
Severe Thunderstorm Watches in Virginia, 2016Severe Thunderstorm Watches in Maryland, 2016Severe Thunderstorm Watches in Pennsylvania, 2016Every severe thunderstorm watch in 2016
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.