Alert archive / Maryland / Tornado Watches in 1998

Tornado Watch 152

April 1, 19985 states

The Storm Prediction Center issued this tornado watch at Apr 1, 1998, 7:15 PM EST for 5 states. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
Apr 1, 1998, 7:15 PM EST (00:15 UTC)
Expired
Apr 2, 1998, 12:00 AM EST
In force
5 hr
Issued by
the Storm Prediction Center
All 57 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, Wicomico County, MD, Worcester County, MD, Burlington County, NJ, Camden County, NJ, Cape May County, NJ, Cumberland County, NJ, Gloucester County, NJ, Salem County, NJ, Adams County, PA, Chester County, PA, Delaware County, PA, Lancaster County, PA, Montgomery County, PA, Philadelphia County, PA, York County, PA, Accomack County, VA, Arlington County, VA, Caroline County, VA, City of Alexandria, VA, City of Fairfax, VA, City of Falls Church, VA, City of Fredericksburg, VA, City of Manassas, VA, City of Manassas Park, VA, Essex County, VA, Fairfax County, VA, Hanover County, VA, King George County, VA, Louisa County, VA, Northumberland County, VA, Prince William County, VA, Richmond County, VA, Spotsylvania County, VA, Stafford County, VA, Westmoreland County, VA

The radar

The Sterling radar (KLWX), 79 km from the middle of the area, began a volume at 00:18 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.

Warnings issued inside it

10 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Apr 1, 7:43 PM ESTTornado WarningAKQEssex, King and Queen32 min
Apr 1, 7:44 PM ESTSevere Thunderstorm WarningCTPLancaster, York61 min
Apr 1, 8:10 PM ESTFlash Flood WarningPHIChester, Montgomery110 min
Apr 1, 8:16 PM ESTTornado WarningAKQEssex, Richmond29 min
Apr 1, 8:32 PM ESTSevere Thunderstorm WarningLWXBaltimore, Harford48 min
Apr 1, 8:39 PM ESTSevere Thunderstorm WarningLWXPrince George's31 min
Apr 1, 9:03 PM ESTSevere Thunderstorm WarningLWXAnne Arundel32 min
Apr 1, 9:06 PM ESTSevere Thunderstorm WarningPHICecil49 min
Apr 1, 9:43 PM ESTSevere Thunderstorm WarningPHINew Castle32 min
Apr 1, 9:56 PM ESTFlash Flood WarningPHIChester, Montgomery2 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 00:00Z, 0.3 hours before the alert went out and 71 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 00:00Z on 1998-04-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1170 joules per kilogram.LCLEL10008507005003002001001 km2 km3 km6 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 00:00Z on 1998-04-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 104 square meters per square second.1939587897Sfc1 km3 km6 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
1170 J/kg
Mixed-layer CIN
-6 J/kg
Mixed-layer LCL
817 m above ground
0-6 km bulk shear
80 kt
0-1 km storm-relative helicity
104 m²/s²
0-3 km storm-relative helicity
192 m²/s²
Significant tornado parameter
0.6
Supercell composite
3.7

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.

Nearby

Tornado Watches in Maryland, 1998Tornado Watches in Virginia, 1998Tornado Watches in Pennsylvania, 1998Every tornado watch in 1998

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.