Alert archive / Delaware / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 31, NWS Philadelphia/Mount Holly

May 6, 1997Sussex County, Delaware

NWS Philadelphia/Mount Holly issued this severe thunderstorm warning at May 6, 1997, 2:21 PM EDT for Sussex County, Delaware. It was in force for 29 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
May 6, 1997, 2:21 PM EDT (18:21 UTC)
Expired
May 6, 1997, 2:50 PM EDT
In force
29 min
Issued by
NWS Philadelphia/Mount Holly
Area
Whole counties

County Sussex County, DE

The radar

The Dover AFB radar (KDOX), 18 km from the middle of the area, began a volume at 18:23 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
May 6, 2:30 PM EDTThunderstorm WindNassau, DE

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 12:00Z, 6.4 hours before the alert went out and 84 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 12:00Z on 1997-05-06Temperature 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°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Wallops Is Stn, VA at 12:00Z on 1997-05-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 25 square meters per square second.1939587897Sfc1 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
1239 m above ground
0-6 km bulk shear
49 kt
0-1 km storm-relative helicity
25 m²/s²
0-3 km storm-relative helicity
84 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
TTAA00 KPHL 061820 RRA
SVRPHL
DEC005-DEZ501-NJC009-NJZ501-061850-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE PHILADELPHIA/MOUNT HOLLY NJ
221 PM EDT TUE MAY 6 1997

THE NATIONAL WEATHER SERVICE IN PHILADELPHIA/MOUNT HOLLY NJ HAS
ISSUED A SEVERE THUNDERSTORM WARNING EFFECTIVE UNTIL 250 PM EDT
FOR PEOPLE IN THE FOLLOWING LOCATION...

IN  NEW JERSEY

   ...CAPE MAY COUNTY

IN  DELAWARE

   ...SUSSEX COUNTY
 
AT 215 PM NATIONAL WEATHER SERVICE DOPPLER RADAR SHOWED VERY STRONG
THUNDERSTORMS IN SUSSEX COUNTY DELAWARE AND IN CAPE MAY
COUNTY NEW JERSEY.  THESE THUNDERSTORMS WERE MOVING EAST AROUND 30
MPH.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT FOR THE AREA.

IF YOU ARE IN THE PATH OF THIS STORM...SEEK SHELTER NOW.  AFTER THE
STORM HAS PASSED...REPORT ANY SEVERE WEATHER OR FLOODING TO YOUR
LOCAL LAW ENFORCEMENT AGENCY AND HAVE THEM RELAY YOUR SEVERE WEATHER
REPORT ON TO THE NATIONAL WEATHER SERVICE.

SEVERE THUNDERSTORMS CONTAIN WINDS GREATER THAN 58 MILES AN HOUR...
DIME SIZE HAIL OR LARGER...VERY HEAVY RAINS AND DEADLY LIGHTNING.

STAY TUNED TO NOAA WEATHER RADIO...THE VOICE OF THE NATIONAL WEATHER
SERVICE...OR TO COMMERCIAL RADIO OR TELEVISION STATIONS FOR THE
LATEST STORM INFORMATION.
 
THIS IS A DANGEROUS STORM. MOVE INSIDE A STRONG BUILDING AND DO NOT
STAND NEAR WINDOWS. DO NOT USE TELEPHONES OR ELECTRICAL APPLIANCES
UNTIL AFTER THE STORM PASSES...UNLESS IN AN EMERGENCY.

The office that day

Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 6, 1:40 PM EDTSevere Thunderstorm WarningPHIKent30 min

Nearby

Severe Thunderstorm Warnings in Delaware, 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; radar from the NEXRAD Level II archive.