Alert archive / North Dakota / Severe Thunderstorm Warnings in 2002

Severe Thunderstorm Warning 347, NWS Grand Forks, ND

September 18, 2002Cass County, Ransom County, Steele County, North Dakota

NWS Grand Forks, ND issued this severe thunderstorm warning at Sep 18, 2002, 3:46 PM CDT for Cass County, Ransom County, Steele County, North Dakota. It was in force for 44 min. 3 reports 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
Sep 18, 2002, 3:46 PM CDT (20:46 UTC)
Expired
Sep 18, 2002, 4:30 PM CDT
In force
44 min
Issued by
NWS Grand Forks, ND
Area
Counties, with a storm outline in the text

Counties Cass County, ND, Ransom County, ND, Steele County, ND

The radar

The Fargo/Grand Forks radar (KMVX), 67 km from the middle of the area, began a volume at 20:48 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
Sep 18, 3:50 PM CDTHail 0.75Lynchburg, ND
Sep 18, 3:51 PM CDTHail 1.75Sheldon, ND
Sep 18, 4:28 PM CDTHail 0.75Amenia, ND

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

Aberdeen, SD (KABR), launched 12:00Z, 8.8 hours before the alert went out and 237 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, Aberdeen, SD at 12:00Z on 2002-09-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 613 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, Aberdeen, SD at 12:00Z on 2002-09-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 60 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
613 J/kg
Mixed-layer CIN
-190 J/kg
Mixed-layer LCL
786 m above ground
0-6 km bulk shear
34 kt
0-1 km storm-relative helicity
60 m²/s²
0-3 km storm-relative helicity
53 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The office that day

Everything else NWS Grand Forks, ND issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Sep 18, 5:28 PM CDTSevere Thunderstorm WarningFGFClay47 min
Sep 18, 5:37 PM CDTSevere Thunderstorm WarningFGFWilkin38 min
Sep 18, 5:53 PM CDTSevere Thunderstorm WarningFGFNorman52 min
Sep 18, 6:16 PM CDTTornado WarningFGFClay44 min
Sep 18, 6:19 PM CDTFlash Flood WarningFGFKittson6 hr
Sep 18, 6:58 PM CDTTornado WarningFGFClay47 min
Sep 18, 6:58 PM CDTTornado WarningFGFClay47 min
Sep 18, 2:21 PM CDTSevere Thunderstorm WarningFGFCass39 min
Sep 18, 3:00 PM CDTSevere Thunderstorm WarningFGFCass45 min
Sep 18, 3:35 PM CDTFlash Flood WarningFGFCass6 hr
Sep 18, 4:20 PM CDTSevere Thunderstorm WarningFGFBarnes25 min
Sep 18, 4:28 PM CDTSevere Thunderstorm WarningFGFRichland32 min
Sep 18, 4:32 PM CDTSevere Thunderstorm WarningFGFCass43 min
Sep 18, 5:16 PM CDTSevere Thunderstorm WarningFGFCass44 min

Nearby

Severe Thunderstorm Warnings in North Dakota, 2002Every severe thunderstorm warning in 2002

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.