Alert archive / Minnesota / Severe Thunderstorm Warnings in 1987

Severe Thunderstorm Warning 14, NWS Grand Forks, ND

July 16, 1987Pennington County, Polk County, Red Lake County, Minnesota; Grand Forks County, North Dakota

NWS Grand Forks, ND issued this severe thunderstorm warning at Jul 16, 1987, 10:58 PM CDT for Pennington County, Polk County, Red Lake County, Minnesota; Grand Forks County, North Dakota. It was in force for 62 min. 2 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
Jul 16, 1987, 10:58 PM CDT (03:58 UTC)
Expired
Jul 17, 1987, 12:00 AM CDT
In force
62 min
Issued by
NWS Grand Forks, ND
Area
Whole counties

Counties Pennington County, MN, Polk County, MN, Red Lake 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
Jul 16, 11:00 PM CDTHail 2.75Polk, MN
Jul 16, 11:00 PM CDTHail 2.75Polk, MN

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

International Fa, MN (KINL), launched 00:00Z, 4.0 hours before the alert went out and 248 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, International Fa, MN at 00:00Z on 1987-07-17Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1601 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, International Fa, MN at 00:00Z on 1987-07-17The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 275 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
1601 J/kg
Mixed-layer CIN
-143 J/kg
Mixed-layer LCL
1339 m above ground
0-6 km bulk shear
46 kt
0-1 km storm-relative helicity
275 m²/s²
0-3 km storm-relative helicity
548 m²/s²
Significant tornado parameter
1.2
Supercell composite
6.5

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.

What forecasters said that day

The local office's own words before this severe thunderstorm warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

In the hours before

Special weather statement, Jul 16, 9:48 PM CDT, 1 hour 10 minutes before
SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE FARGO ND
945 PM CDT THU JUL 16 1987

...THUNDERSTORMS DEVELOPING RADIDLY OVER NORTHEAST NORTH DAKOTA...

AT 945 PM A STRONG THUNDERSTORM WAS LOCATED JUST SOUTHWEST OF
GRAND FORKS NORTH DAKOTA MOVING TOWARD THE NORTHEAST AT 30 MILES
AN HOUR. THIS THUNDERSTORM SHOULD PASS OVER GRAND FORKS NORTH
DAKOTA AND CONTINUE ON NORTHEAST AND WILL BE IN THE THIEF RIVER
FALLS AREA BY 1030 PM.

THIS TH[UNDERSTORM COULD PRODUCE BRIEF HEAVY RAIN..SMALL HAIL AND
GUSTY SURFACE WINDS.

OTHER THUNDERSTORMS WERE LOCATED OVER CENTRAL AND EAST CENTRAL
NORTH DAKOTA..ALSO MOVING NORTHEAST AT 30 MILES AN HOUR.
ANDERSEN

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 16, 10:02 PM CDTSevere Thunderstorm WarningFGFMarshall, Polk58 min
Jul 17, 3:40 AM CDTSevere Thunderstorm WarningFGFBeltrami30 min
Jul 17, 4:10 AM CDTSevere Thunderstorm WarningFGFKoochiching50 min
Jul 17, 2:50 AM CDTSevere Thunderstorm WarningFGFCass, Steele, Traill55 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.