Alert archive / North Dakota / Severe Thunderstorm Warnings in 1999

Severe Thunderstorm Warning 229, NWS Grand Forks, ND

August 9, 1999Cass County, North Dakota

NWS Grand Forks, ND issued this severe thunderstorm warning at Aug 9, 1999, 5:02 AM CDT for Cass County, North Dakota. It was in force for 33 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
Aug 9, 1999, 5:02 AM CDT (10:02 UTC)
Expired
Aug 9, 1999, 5:35 AM CDT
In force
33 min
Issued by
NWS Grand Forks, ND
Area
Whole counties

County Cass County, ND

What was reported inside it

TimeReportWhereRemark
Aug 9, 5:15 AM CDTHail 0.88Casselton, 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 watch it was issued in

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

IssuedProductOfficeLasted
Aug 9, 2:30 AM CDTSevere Thunderstorm WatchSPC6 hr

The nearest sounding before it

Aberdeen, SD (KABR), launched 00:00Z, 10.0 hours before the alert went out and 243 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 00:00Z on 1999-08-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 590 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 00:00Z on 1999-08-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 80 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
590 J/kg
Mixed-layer CIN
-249 J/kg
Mixed-layer LCL
1278 m above ground
0-6 km bulk shear
60 kt
0-1 km storm-relative helicity
80 m²/s²
0-3 km storm-relative helicity
221 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.3

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 Grand Forks, ND issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 8, 11:29 PM CDTSevere Thunderstorm WarningFGFRansom, Richland31 min
Aug 8, 11:58 PM CDTSevere Thunderstorm WarningFGFRichland32 min
Aug 9, 12:28 AM CDTSevere Thunderstorm WarningFGFRichland32 min
Aug 9, 12:59 AM CDTSevere Thunderstorm WarningFGFRichland36 min
Aug 9, 3:46 AM CDTSevere Thunderstorm WarningFGFGriggs34 min
Aug 9, 4:08 AM CDTSevere Thunderstorm WarningFGFBarnes32 min
Aug 9, 4:24 AM CDTSevere Thunderstorm WarningFGFCass36 min
Aug 9, 1:25 AM CDTSevere Thunderstorm WarningFGFGrant35 min
Aug 9, 1:47 AM CDTSevere Thunderstorm WarningFGFOtter Tail33 min
Aug 9, 1:58 AM CDTSevere Thunderstorm WarningFGFGrant32 min
Aug 9, 2:43 AM CDTSevere Thunderstorm WarningFGFOtter Tail32 min
Aug 9, 3:10 AM CDTSevere Thunderstorm WarningFGFWadena35 min
Aug 9, 6:13 AM CDTSevere Thunderstorm WarningFGFOtter Tail, Wilkin32 min
Aug 9, 7:20 AM CDTSevere Thunderstorm WarningFGFOtter Tail20 min

Nearby

Severe Thunderstorm Warnings in North Dakota, 1999Every severe thunderstorm warning in 1999

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.