Alert archive / North Dakota / Tornado Warnings in 1986

Tornado Warning 8, NWS Grand Forks, ND

July 10, 1986Cass County, North Dakota; Clay County, Minnesota

NWS Grand Forks, ND issued this tornado warning at Jul 10, 1986, 6:36 PM CDT for Cass County, North Dakota; Clay County, Minnesota. It was in force for 54 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 10, 1986, 6:36 PM CDT (23:36 UTC)
Expired: Jul 10, 1986, 7:30 PM CDT
In force: 54 min
Issued by: NWS Grand Forks, ND
Area: Whole counties

Counties Clay County, MN, Cass 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

Time	Report	Where	Remark
Jul 10, 7:03 PM CDT	Tornado F0	Cass, ND
Jul 10, 7:24 PM CDT	Tornado F0	Cass, 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

Aberdeen, SD (KHON), launched 12:00Z, 11.6 hours before the alert went out and 253 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1117 J/kg
Mixed-layer CIN: -1 J/kg
Mixed-layer LCL: 492 m above ground
0-6 km bulk shear: 31 kt
0-1 km storm-relative helicity: 89 m²/s²
0-3 km storm-relative helicity: 197 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 5.5

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
TTAA00 KFAR 102336
TORFAR
NDC017-MNC027-110030-

BULLETIN - IMMEDIATE BROADCAST REQUESTED/EBS ACTIVATION REQUESTED 
TORNADO WARNING
NATIONAL WEATHER SERVICE FARGO ND
636 PM CDT THU JUL 10 1986

THE NATIONAL WEATHER SERVICE HAS ISSUED A TORNADO WARNING 
EFFECTIVE UNTIL 730 PM CDT FOR PEOPLE IN THE FOLLOWING COUNTIES OF

EAST CENTRAL NORTH DAKOTA...CASS AND THE CITIES OF FARGO/MOORHEAD
NORTHWEST MINNESOTA...WESTERN CLAY

AT 625 PM CDT RADAR INDICATED A POSSIBLE TORNADO NEAR MAPLETON
NORTH DAKOTA..25 MILES WEST OF FARGO NORTH DAKOTA MOVING EAST
AT 5 MILES AN HOUR.

THIS STORM IS ACCOMPANIED BY INTENSE LIGHTNING..LARGE HAIL..AND
DANGEROUS STRAIGHT LINE WINDS.

THIS STORM MAY ALSO CAUSE FLOODING OF SMALL STREAMS AND UNDERPASSES.

IF A TORNADO IS APPROACHING GET INTO A BASEMENT...IF NO BASEMENT
IS AVAILABLE...GET INTO THE INNERMOST HALLWAY...STAY AWAY FROM
WINDOWS.  IF CAUGHT OUTSIDE GET INTO A DITCH...GULLY...RAVINE...OR
EVEN A LOW LYING SPOT ON THE TGROUND.  PROTECT YOUR HEAD.  ABANDON
CARS AND MOBILE HOMES.

IF THREATENING WEATHER APPROACHES...YOU SHOULD GO TO A SAFE PLACE
IMMEDIATELY.

ANDERSEN

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 10, 1:51 PM CDT	Tornado Warning	FGF	Grand Forks, Steele	69 min
Jul 10, 4:31 PM CDT	Tornado Warning	FGF	Grand Forks, Steele	59 min
Jul 10, 4:42 PM CDT	Tornado Warning	FGF	Cass	48 min
Jul 10, 5:35 PM CDT	Severe Thunderstorm Warning	FGF	Cass	55 min
Jul 10, 5:35 PM CDT	Severe Thunderstorm Warning	FGF	Traill	55 min

Nearby

Tornado Warnings in North Dakota, 1986 Tornado Warnings in Minnesota, 1986 Every tornado warning in 1986 Tornadoes in 1986

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.