Alert archive / Minnesota / Severe Thunderstorm Warnings in 1987

Severe Thunderstorm Warning 19, NWS Grand Forks, ND

July 17, 1987Beltrami County, Clearwater County, Minnesota

NWS Grand Forks, ND issued this severe thunderstorm warning at Jul 17, 1987, 7:44 PM CDT for Beltrami County, Clearwater County, Minnesota. It was in force for 76 min.

The area

The counties it named.

The facts

Issued
Jul 17, 1987, 7:44 PM CDT (00:44 UTC)
Expired
Jul 17, 1987, 9:00 PM CDT
In force
76 min
Issued by
NWS Grand Forks, ND
Area
Whole counties

Counties Beltrami County, MN, Clearwater County, MN

The radar

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

The nearest sounding before it

International Fa, MN (KINL), launched 00:00Z, 0.7 hours before the alert went out and 164 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 1987-07-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 7 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 1987-07-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 20 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
7 J/kg
Mixed-layer CIN
-214 J/kg
Mixed-layer LCL
1101 m above ground
0-6 km bulk shear
24 kt
0-1 km storm-relative helicity
20 m²/s²
0-3 km storm-relative helicity
145 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.

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 17, 4:38 PM CDT, 3 hours 6 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE FARGO ND
430 PM CDT FRI JUL 17 1987

...THUNDERSTORMS FIRE-UP OVER NORTHWEST MINNESOTA...

AT 426 PM CDT SEVERAL THUNDERSTORMS WITH VERY HEAVY RAIN HAD
DEVELOPED QUITE RAPIDLY OVER PARTS OF NORTHWEST MINNESOTA.

THE STORMS WERE 10 MILES NORTHWEST OF DETROIT LAKES AND IN A
CLUSTER AROUND ITASCA STATE PARK. THESE STORMS WERE MOVING
NORTHEAST AT 35 MILES AN HOUR AND SHOULD MOVE INTO THE BEMIDJI
AREA BY 515 PM.

THESE STORMS HAVE THE POTENTIAL TO PRODUCE HAIL..GUSTY WIND AND
DANGEROUS LIGHTNING..IN ADDITION TO THE VERY HEAVY RAIN.

PERSONS IN THE PATH OF THESE STORMS SHOULD BE ALERT TO RAPIDLY
CHANGING WEATHER CONDITIONS AND BE PREPARED TO GO TO A PLACE OF
SAFETY.

OTHER SHOWERS AND THUNDERSHOWERS WERE OVER THE EXTREME NORTHEAST
CORNER OF NORTH DAKOTA AND OVER THE NORTH ONE-THIRD OF MINNESOTA.

MOVEMENT WAS NORTHEAST AT ABOUT 35 MILES AN HOUR.
BENNETT
Special weather statement, Jul 17, 5:43 PM CDT, 2 hours 1 minute before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE FARGO ND
535 PM CDT FRI JUL 17 1987

AT 529 PM CDT AN INTENSE THUNDERSTORM WAS LOCATED ABOUT THREE
MILES WEST OF ITASCA STATE PARK IN CLEARWATER COUNTY OF NORTHWEST
MINNESOTA.

THIS STORM WAS MOVING EAST AT ABOUT 30 MILES AN HOUR AND SHOULD
MOVE JUST TO THE SOUTHEAST OF BEMIDJI BY 630 PM.

OTHER THUNDERSTORMS..SOME WITH VERY HEAVY RAIN WERE FROM ABOUT
30 MILES NORTHWEST OF DETROIT LAKES TO GRAND RAPIDS..BOTH IN MINNESOTA.

OTHER SHOWERS WERE OVER THE NORTH END OF THE RED RIVER VALLEY.

MOVEMENT WAS EAST AT 30 MILES AN HOUR.

NO REPORTS OF SEVERE WEATHER HAD BEEN RECEIVED SINCE 426 PM.
BENNETT
Special weather statement, Jul 17, 6:50 PM CDT, 54 minutes before
SPECIAL WEATHER STATEMENT AND RADAR SUMMARY
NATIONAL WEATHER SERVICE FARGO ND
638 PM CDT FRI JUL 17 1987

AT 629 PM CDT A CLUSTER OF INTENSE THUNDERSTORMS WAS OVER THE
SOUTHEAST CORNER OF MAHNOMEN COUNTY OF NORTHWEST MINNESOTA..
ABOUT 30 MILES NORTH OF DETROIT LAKES.

THESE STORMS WERE MOVING NORTHEAST AT 30 MILES AN HOUR AND SHOULD
MOVE INTO THE SOUTHWEST CORNER OF CLEARWATER COUNTY BY 715 PM.

REPORTS OF VERY HEAVY RAIN HAVE BEEN ASSOCIATED WITH THE STORMS OVER
THIS GENERAL AREA SINCE 530 PM. NO SEVERE WEATHER HAD BEEN REPORTED.

OTHER SHOWERS AND THUNDERSTORMS WITH VERY HEAVY RAIN EXTENDED FROM
30 MILES NORTH OF DETROIT LAKES TO THE NORTH OF HIBBING IN MINNESOTA.

MOVEMENT WAS NORTHEAST AT 30 MILES AN HOUR.

PEOPLE LIVING IN THE LOWER ELEVATIONS OF MAHNOMEN..NORTH BECKER AND
SOUTH CLEARWATER COUNTIES OF NORTHWEST MINNESOTA SHOULD BE ALERT FOR
STANDING WATER CAUSED BY VERY HEAVY RAIN..DO NOT ATTEMPT TO CROSS
THROUGH STAN)DING WATER IN AREAS UNFAMILIAR TO YOU. ANYONE LIVING
NEAR SMALL STREAMS SHOULD KEEP ALERT FOR RISING WATERS AND BE PREPARED
TO MOVE TO HIGHER GROUND.
BENNETT

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 17, 7:37 PM CDTSevere Thunderstorm WarningFGFBecker68 min
Jul 18, 4:50 PM CDTTornado WarningFGFBeltrami30 min

Nearby

Severe Thunderstorm Warnings in Minnesota, 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; the sounding from the Mesonet's radiosonde archive.