Alert archive / Maryland / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 69, NWS Baltimore/Washington

July 18, 1997Calvert County, Charles County, Maryland

NWS Baltimore/Washington issued this severe thunderstorm warning at Jul 18, 1997, 8:20 PM EDT for Calvert County, Charles County, Maryland. It was in force for 50 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
Jul 18, 1997, 8:20 PM EDT (00:20 UTC)
Expired
Jul 18, 1997, 9:10 PM EDT
In force
50 min
Issued by
NWS Baltimore/Washington
Area
Whole counties

Counties Calvert County, MD, Charles County, MD

What was reported inside it

TimeReportWhereRemark
Jul 18, 8:25 PM EDTThunderstorm Wind 61Waldorf, MD

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 nearest sounding before it

Wallops Is Stn, VA (KWAL), launched 00:00Z, 0.3 hours before the alert went out and 136 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, Wallops Is Stn, VA at 00:00Z on 1997-07-19Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2691 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, Wallops Is Stn, VA at 00:00Z on 1997-07-19The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 71 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
2691 J/kg
Mixed-layer CIN
-29 J/kg
Mixed-layer LCL
1477 m above ground
0-6 km bulk shear
25 kt
0-1 km storm-relative helicity
71 m²/s²
0-3 km storm-relative helicity
132 m²/s²
Significant tornado parameter
0.0
Supercell composite
4.3

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.

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 18, 8:01 PM EDTSevere Thunderstorm WarningLWXCharles, Prince George's29 min
Jul 18, 8:35 PM EDTTornado WarningLWXSaint Mary's35 min
Jul 18, 8:35 PM EDTTornado WarningLWXCalvert, Prince George's35 min

Nearby

Severe Thunderstorm Warnings in Maryland, 1997Every severe thunderstorm warning in 1997

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.