Alert archive / Minnesota / Severe Thunderstorm Warnings in 1987

Severe Thunderstorm Warning 73, NWS Grand Forks, ND

August 5, 1987Polk County, Minnesota; Grand Forks County, North Dakota

NWS Grand Forks, ND issued this severe thunderstorm warning at Aug 5, 1987, 7:39 PM CDT for Polk County, Minnesota; Grand Forks County, North Dakota. It was in force for 66 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
Aug 5, 1987, 7:39 PM CDT (00:39 UTC)
Expired
Aug 5, 1987, 8:45 PM CDT
In force
66 min
Issued by
NWS Grand Forks, ND
Area
Whole counties

Counties Polk County, MN, Grand Forks County, ND

The radar

The WSR-88D network and its archive begin in 1991, so there is no radar volume for this alert.

What was reported inside it

TimeReportWhereRemark
Aug 5, 7:59 PM CDTHail 1.75Grand Forks, ND
Aug 5, 8:25 PM CDTHail 1.75Grand Forks, ND
Aug 5, 8:35 PM CDTHail 1.75Grand Forks, 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. Storm Data before 1996 records only tornadoes, thunderstorm wind and hail.

The nearest sounding before it

Bismarck Municip, ND (KBIS), launched 00:00Z, 0.7 hours before the alert went out and 308 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, Bismarck Municip, ND at 00:00Z on 1987-08-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 282 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, Bismarck Municip, ND at 00:00Z on 1987-08-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -78 square meters per square second.19395878Sfc1 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
282 J/kg
Mixed-layer CIN
-257 J/kg
Mixed-layer LCL
2542 m above ground
0-6 km bulk shear
27 kt
0-1 km storm-relative helicity
-78 m²/s²
0-3 km storm-relative helicity
-33 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.8

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 5, 7:49 PM CDTTornado WarningFGFPolk56 min
Aug 5, 8:50 PM CDTSevere Thunderstorm WarningFGFPennington, Polk55 min
Aug 5, 7:00 PM CDTSevere Thunderstorm WarningFGFCavalier60 min
Aug 5, 7:05 PM CDTTornado WarningFGFNelson60 min
Aug 5, 7:14 PM CDTSevere Thunderstorm WarningFGFSteele, Traill56 min
Aug 5, 8:05 PM CDTSevere Thunderstorm WarningFGFGrand Forks, Nelson55 min
Aug 5, 8:32 PM CDTSevere Thunderstorm WarningFGFSteele58 min
Aug 5, 8:50 PM CDTSevere Thunderstorm WarningFGFGrand Forks55 min
Aug 5, 8:57 PM CDTSevere Thunderstorm WarningFGFTraill63 min

Nearby

Severe Thunderstorm Warnings in Minnesota, 1987Severe Thunderstorm Warnings in North Dakota, 1987Every severe thunderstorm warning in 1987

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.