Alert archive / Maryland / Severe Thunderstorm Warnings in 2000

Severe Thunderstorm Warning 18, NWS Baltimore/Washington

April 21, 2000Prince George's County, Maryland

NWS Baltimore/Washington issued this severe thunderstorm warning at Apr 21, 2000, 4:39 PM EDT for Prince George's County, Maryland. It was in force for 36 min. 1 report came from inside the area while it was in force.

The area

The counties it named, with what was reported inside it.

The facts

Issued
Apr 21, 2000, 4:39 PM EDT (20:39 UTC)
Expired
Apr 21, 2000, 5:15 PM EDT
In force
36 min
Issued by
NWS Baltimore/Washington
Area
Whole counties

County Prince George's County, MD

The radar

The Sterling radar (KLWX), 58 km from the middle of the area, began a volume at 20:39 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 was reported inside it

TimeReportWhereRemark
Apr 21, 5:00 PM EDTHail 0.88Rosaryville, MDNickel sized hail fell.

NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

IssuedProductOfficeLasted
Apr 21, 12:00 PM EDTSevere Thunderstorm WatchSPC5 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 8.7 hours before the alert went out and 50 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, Washington/Dulle, VA at 12:00Z on 2000-04-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Washington/Dulle, VA at 12:00Z on 2000-04-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 230 square meters per square second.19395878Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
626 m above ground
0-6 km bulk shear
52 kt
0-1 km storm-relative helicity
230 m²/s²
0-3 km storm-relative helicity
254 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.0

Open this sounding in Storm Lab

The text

The text of this product is not in the archive. The NWS text archive before 2002 is incomplete.

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 Apr 21, 2:45 PM EDT, 1 hour 54 minutes earlier.

Area forecast discussion, Apr 21, 2:45 PM EDT, 1 hour 54 minutes before
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The office that day

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

IssuedProductOfficeCountiesLasted
Apr 21, 1:32 PM EDTSevere Thunderstorm WarningLWXCulpeper, Fauquier, Spotsylvania, Stafford43 min
Apr 21, 2:10 PM EDTSevere Thunderstorm WarningLWXPrince William50 min
Apr 21, 2:21 PM EDTSevere Thunderstorm WarningLWXSpotsylvania, City of Fredericksburg24 min
Apr 21, 2:10 PM EDTSevere Thunderstorm WarningLWXCharles, Prince George's50 min
Apr 21, 2:33 PM EDTTornado WarningLWXCharles27 min
Apr 21, 3:03 PM EDTSevere Thunderstorm WarningLWXAnne Arundel, Prince George's57 min
Apr 21, 3:03 PM EDTSevere Thunderstorm WarningLWXCharles57 min
Apr 21, 4:16 PM EDTSevere Thunderstorm WarningLWXHoward, Montgomery59 min
Apr 21, 5:05 PM EDTSevere Thunderstorm WarningLWXAnne Arundel, Baltimore, City of Baltimore55 min

Nearby

Severe Thunderstorm Warnings in Maryland, 2000Every severe thunderstorm warning in 2000

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.