Alert archive / Minnesota / Tornado Warnings in 1987

Tornado Warning 19, NWS Twin Cities, MN

July 23, 1987Anoka County, Hennepin County, Minnesota

NWS Twin Cities, MN issued this tornado warning at Jul 23, 1987, 6:40 PM CDT for Anoka County, Hennepin County, Minnesota. It was in force for 65 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: Jul 23, 1987, 6:40 PM CDT (23:40 UTC)
Expired: Jul 23, 1987, 7:45 PM CDT
In force: 65 min
Issued by: NWS Twin Cities, MN
Area: Whole counties

Counties Anoka County, MN, Hennepin County, MN

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
Jul 23, 6:47 PM CDT	Tornado F3	Hennepin, MN
Jul 23, 7:23 PM CDT	Thunderstorm Wind 0	Hennepin, MN
Jul 23, 7:40 PM CDT	Hail 0.8	Hennepin, 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

Minneapolis, MN (KSTC), launched 12:00Z, 11.7 hours before the alert went out and 37 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: 575 J/kg
Mixed-layer CIN: -138 J/kg
Mixed-layer LCL: 1013 m above ground
0-6 km bulk shear: 34 kt
0-1 km storm-relative helicity: -16 m²/s²
0-3 km storm-relative helicity: -25 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.3

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KMSP 232340
TORMSP
MNC053-003-240045-

BULLETIN - IMMEDIATE BROADCAST REQUESTED/EBS ACTIVATION REQUESTED 
TORNADO WARNING
NATIONAL WEATHER SERVICE MINNEAPOLIS MN
640 PM CDT THU JUL 23 1987

THE NATIONAL WEATHER SERVICE HAS ISSUED A TORNADO WARNING 
EFFECTIVE UNTIL 745 PM CDT FOR PEOPLE IN THE FOLLOWING COUNTIES OF

EAST CENTRAL MINNESOTA...NORTHERN HENNEPIN AND SOUTHERN ANOKA


AT 635 PM CDT FUNNEL CLOUDS HAVE BEEN REPORTED NEAR THE CITY
OF CHAMPLIN ALONG THE NORTHWEST HENNEPIN...SOUTHWEST ANOKA
COUNTY BORDER IN EAST CENTRAL MINNESOTA OR ABOUT 30 MILES
NORTHWEST OF DOWNTOWN MINNEAPOLIS. THE FUNNELS WERE MOVING
EAST AT 30 MPH.

PERSONS IN BROOKLYN PARK...ANOKA...AND CHAMPLIN SHOULD TAKE
SHELTER IMMEDIATELY.

THIS IS A DANGEROUS STORM SITUATION.  ACT QUICKLY.  IF YOU ARE IN
THE PATH OF A TORNADO MOVE TO A SHELTER BELOW GROUND IF AVAILABLE.
OTHERWISE..GO TO A SMALL INTERIOR ROOM ON THE LOWEST FLOOR
POSSIBLE.  AVOID WINDOWS.  ABANDON CARS AND] MOBILE HOMES FOR A
REINFORCED BUILDING OR GET INTO A DITCH OR CULVERT.

NAISTAT

What forecasters said that day

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

In the hours before

Local storm report, Jul 23, 3:38 PM CDT, 3 hours 2 minutes before

LOCAL STORM REPORT
NATIONAL WEATHER SERVICE ST CLOUD, MN
335 PM CDT THU JUL 23 1987

...ATTN SELS...

SEVERE WEATHER REPORT FROM 23 JUL 1987

1218 PM CDT 1/2 INCH HAIL AT FOLEY MINNESOTA...10 MILES NORTHEAST OF
              ST. CLOUD.
1221 PM CDT 3/4 TO 1 INCH HAIL IN NOTHERN SECTIONS OF ST. CLOUD.
1230 PM CDT LARGE TREES DOWN...POWER POLES AND POWER LINES DOWN IN
            SAUK RAPIDS MINNESOTA...A NORTHERN SUBURB OF ST. CLOUD.

FRASER

Special weather statement, Jul 23, 5:13 PM CDT, 1 hour 27 minutes before

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE ST. CLOUD MN
505 PM CDT THU JUL 23 1987

...TORNADO WATCH CENTRAL MINNESOTA UNTIL 900 PM CDT...

RADAR SHOWED AN AREA OF STRONG THUNDERSTORMS DEVELOPING RAPIDLY IN
SOUTHERN SHERBURNE COUNTY.  THESE THUNDERSTORMS MAY PRODUCE LOCALLY
HEAVY RAINFALL AND SMALL HAIL.

PEOPLE IN SOUTHERN SHERBURNE COUNTY AND ESPECIALLY NEAR THE CITIES
OF BECKER... BIG LAKE AND ELK RIVER SHOULD BE PREPARED TO MOVE TO A
PLACE OF SAFETY IF SEVERE WEATHER DEVELOPES.

FRASER

The office that day

Everything else NWS Twin Cities, MN issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 23, 12:15 PM CDT	Severe Thunderstorm Warning	MPX	Benton, Sherburne, Stearns	60 min
Jul 23, 12:15 PM CDT	Severe Thunderstorm Warning	MPX	Mille Lacs	60 min
Jul 23, 1:11 PM CDT	Severe Thunderstorm Warning	MPX	Anoka, Isanti	49 min
Jul 23, 2:08 PM CDT	Severe Thunderstorm Warning	MPX	Washington	52 min
Jul 23, 5:15 PM CDT	Severe Thunderstorm Warning	MPX	Sherburne	60 min
Jul 23, 5:33 PM CDT	Severe Thunderstorm Warning	MPX	Wright	42 min
Jul 23, 6:16 PM CDT	Severe Thunderstorm Warning	MPX	Anoka, Hennepin, Wright	59 min

Nearby

Tornado Warnings in Minnesota, 1987 Every tornado warning in 1987 Tornadoes 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.