Alert archive / Virginia / Severe Thunderstorm Warnings in 2017

Severe Thunderstorm Warning 166, NWS Baltimore/Washington

July 22, 2017Albemarle County, Virginia

NWS Baltimore/Washington issued this severe thunderstorm warning at Jul 22, 2017, 10:42 PM EDT for Albemarle County, Virginia. It was in force for 15 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Jul 22, 2017, 10:42 PM EDT (02:42 UTC)
Expired
Jul 22, 2017, 10:57 PM EDT
In force
15 min
Issued by
NWS Baltimore/Washington
Area
Storm-based polygon
Hail
0.75 in
Wind
60.0 mph

County Albemarle County, VA

The radar

The Sterling radar (KLWX), 141 km from the middle of the area, began a volume at 02:45 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.

The nearest sounding before it

Roanoke, VA (KRNK), launched 00:00Z, 2.7 hours before the alert went out and 124 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-pSkew-T log-p diagram, Roanoke, VA at 00:00Z on 2017-07-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 634 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Roanoke, VA at 00:00Z on 2017-07-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 72 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
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
634 J/kg
Mixed-layer CIN
-33 J/kg
Mixed-layer LCL
1871 m above ground
0-6 km bulk shear
19 kt
0-1 km storm-relative helicity
72 m²/s²
0-3 km storm-relative helicity
186 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.9

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Baltimore/Washington wrote its last area forecast discussion before this severe thunderstorm warning went out at Jul 22, 8:45 PM EDT, 1 hour 57 minutes earlier.

Area forecast discussion, Jul 22, 8:45 PM EDT, 1 hour 57 minutes before
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Hazardous weather outlook, Jul 22, 8:10 PM EDT, 2 hours 32 minutes before
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In the hours before

Local storm report, Jul 22, 8:41 PM EDT, 2 hours 1 minute before
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Local storm report, Jul 22, 10:17 PM EDT, 25 minutes before
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Local storm report, Jul 22, 10:18 PM EDT, 24 minutes before
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Local storm report, Jul 22, 10:19 PM EDT, 23 minutes before
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Local storm report, Jul 22, 10:36 PM EDT, 6 minutes before
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      <p id="message2">
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Local storm report, Jul 22, 10:42 PM EDT, 0 minutes before
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      <h1 id="headline">This service is currently unavailable.</h1>
      <p id="message1">
        The site you requested is temporarily down for maintenance or an unexpected outage.
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      <p id="message2">
        Please try again in a few minutes.
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        If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
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The office that day

Everything else NWS Baltimore/Washington issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 22, 8:39 PM EDTSpecial Marine WarningLWX66 min
Jul 22, 9:24 PM EDTSpecial Marine WarningLWX66 min
Jul 22, 9:50 PM EDTSevere Thunderstorm WarningLWXAlbemarle, Greene, Madison, Orange, City of Charlottesville40 min
Jul 22, 10:00 PM EDTSpecial Marine WarningLWX90 min
Jul 22, 10:03 PM EDTSpecial Marine WarningLWX87 min
Jul 22, 10:32 PM EDTSevere Thunderstorm WarningLWXOrange, Spotsylvania43 min
Jul 22, 10:59 PM EDTSpecial Marine WarningLWX61 min
Jul 22, 11:25 PM EDTSpecial Marine WarningLWX2 hr
Jul 23, 2:26 PM EDTSpecial Marine WarningLWX64 min
Jul 23, 2:53 PM EDTSpecial Marine WarningLWX67 min
Jul 23, 3:10 PM EDTSpecial Marine WarningLWX95 min
Jul 23, 5:31 PM EDTSpecial Marine WarningLWX89 min
Jul 23, 5:34 PM EDTSpecial Marine WarningLWX86 min
Jul 23, 6:40 PM EDTSpecial Marine WarningLWX65 min
Jul 23, 6:44 PM EDTSpecial Marine WarningLWX2 hr
Jul 23, 3:06 PM EDTSevere Thunderstorm WarningLWXHarford39 min
Jul 23, 3:44 PM EDTSevere Thunderstorm WarningLWXHarford14 min
Jul 23, 4:59 PM EDTFlash Flood WatchLWXAnne Arundel, Baltimore, Carroll, Frederick, Harford, Howard and 3 more9 hr
Jul 23, 5:01 PM EDTAreal Flood WarningLWXMontgomery, Prince George's4 hr
Jul 23, 5:19 PM EDTFlash Flood WarningLWXHarford3 hr
Jul 23, 5:45 PM EDTAreal Flood WarningLWXHarford5 hr
Jul 23, 7:05 PM EDTFlash Flood WarningLWXHarford3 hr
Jul 23, 7:10 PM EDTAreal Flood WarningLWXBaltimore, Harford4 hr
Jul 23, 7:55 PM EDTAreal Flood WarningLWXHarford9 hr

Nearby

Severe Thunderstorm Warnings in Virginia, 2017Every severe thunderstorm warning in 2017

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.