Alert archive / Virginia / Freeze Watches in 2021

Freeze Watch 2, NWS Baltimore/Washington

April 21, 202122 counties in Virginia; Carroll County, Frederick County, Washington County, Maryland; Berkeley County, Jefferson County, Morgan County, West Virginia

NWS Baltimore/Washington issued this freeze watch at Apr 21, 2021, 9:06 PM EDT for 22 counties in Virginia; Carroll County, Frederick County, Washington County, Maryland; Berkeley County, Jefferson County, Morgan County, West Virginia. It took effect at Apr 23, 2021, 2:00 AM EDT. It was in force for .

The area

The counties it named.

The facts

Issued: Apr 21, 2021, 9:06 PM EDT (01:06 UTC)
In effect from: Apr 23, 2021, 2:00 AM EDT
Expired: Apr 22, 2021, 12:03 PM EDT
In force
Issued by: NWS Baltimore/Washington

All 28 counties

Carroll County, MD, Frederick County, MD, Washington County, MD, Albemarle County, VA, Amherst County, VA, Augusta County, VA, City of Charlottesville, VA, City of Harrisonburg, VA, City of Staunton, VA, City of Waynesboro, VA, City of Winchester, VA, Clarke County, VA, Culpeper County, VA, Fauquier County, VA, Frederick County, VA, Greene County, VA, Loudoun County, VA, Madison County, VA, Nelson County, VA, Page County, VA, Rappahannock County, VA, Rockbridge County, VA, Rockingham County, VA, Shenandoah County, VA, Warren County, VA, Berkeley County, WV, Jefferson County, WV, Morgan County, WV

The radar

The Sterling radar (KLWX), 81 km from the middle of the area, began a volume at 01:06 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, 1.1 hours before the alert went out and 194 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1162 m above ground
0-6 km bulk shear: 85 kt
0-1 km storm-relative helicity: -71 m²/s²
0-3 km storm-relative helicity: 77 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this freeze watch 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 freeze watch went out at Apr 21, 2:50 PM EDT, 6 hours 16 minutes earlier.

Area forecast discussion, Apr 21, 2:50 PM EDT, 6 hours 16 minutes before

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Hazardous weather outlook, Apr 21, 8:04 PM EDT, 1 hour 2 minutes before

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In the hours before

Local storm report, Apr 21, 5:54 PM EDT, 3 hours 12 minutes before

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Local storm report, Apr 21, 6:46 PM EDT, 2 hours 20 minutes before

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Local storm report, Apr 21, 7:16 PM EDT, 1 hour 50 minutes before

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Local storm report, Apr 21, 8:35 PM EDT, 31 minutes before

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Local storm report, Apr 21, 8:36 PM EDT, 30 minutes before

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Local storm report, Apr 21, 8:39 PM EDT, 27 minutes before

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The office that day

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

Issued	Product	Office	Counties	Lasted
Apr 22, 10:33 AM EDT	Gale Warning	LWX		7 hr
Apr 22, 10:33 AM EDT	Small Craft Advisory	LWX		11 hr
Apr 22, 12:03 PM EDT	Frost Advisory	LWX	Arlington, King George, City of Alexandria, City of Falls Church	20 hr
Apr 22, 12:03 PM EDT	Freeze Warning	LWX	Albemarle, Amherst, Augusta, Clarke, Culpeper, Fairfax and 22 more	20 hr
Apr 22, 2:14 PM EDT	Special Marine Warning	LWX		2 hr

Nearby

Freeze Watches in Virginia, 2021 Freeze Watches in Maryland, 2021 Freeze Watches in West Virginia, 2021 Every freeze watch in 2021

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.