Alert archive / Minnesota / Severe Thunderstorm Warnings in 1997

Severe Thunderstorm Warning 95, NWS Twin Cities, MN

July 1, 1997Chisago County, Washington County, Minnesota

NWS Twin Cities, MN issued this severe thunderstorm warning at Jul 1, 1997, 8:10 PM CDT for Chisago County, Washington County, Minnesota. It was in force for 50 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 1, 1997, 8:10 PM CDT (01:10 UTC)
Expired: Jul 1, 1997, 9:00 PM CDT
In force: 50 min
Issued by: NWS Twin Cities, MN
Area: Whole counties

Counties Chisago County, MN, Washington County, MN

The radar

The Minneapolis radar (KMPX), 70 km from the middle of the area, began a volume at 01:14 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

What was reported inside it

Time	Report	Where	Remark
Jul 1, 8:15 PM CDT	Tornado F1	Forest Lake, MN	Touchdown on south shore of Forest Lake.
Jul 1, 8:30 PM CDT	Thunderstorm Wind 55	Hugo, MN	Trees and power lines down. Estimated windspeed.
Jul 1, 8:30 PM CDT	Thunderstorm Wind 55	Lindstrom, MN	Trees and power lines down. Estimated windspeed.

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.

The watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Jul 1, 3:00 PM CDT	Tornado Watch	SPC	6 hr
Jul 1, 7:45 PM CDT	Tornado Watch	SPC	5 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 1.2 hours before the alert went out and 72 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: 1759 J/kg
Mixed-layer CIN: -17 J/kg
Mixed-layer LCL: 1186 m above ground
0-6 km bulk shear: 63 kt
0-1 km storm-relative helicity: 303 m²/s²
0-3 km storm-relative helicity: 455 m²/s²
Significant tornado parameter: 4.3
Supercell composite: 21.5

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KMSP 020111 RRA
SVRMSP
MNC025-163-020200-

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
810 PM CDT TUE JUL 1 1997

* SEVERE THUNDERSTORM WARNING FOR
  CHISAGO COUNTY - EAST CENTRAL MINNESOTA
  WASHINGTON COUNTY - EAST CENTRAL MINNESOTA

* UNTIL 900 PM CDT
 
* SOME LOCATIONS AFFECTED
    CENTER CITY
    CHISAGO CITY
    STILLWATER
    MARINE ON ST. CROIX

* AT 805 PM CDT DOPPLER RADAR INDICATED A LINE OF SEVERE STORMS
  FROM CAMBRIDGE THROUGH ST. PAUL.  THE STORMS WERE MOVING EAST AT
  40 MPH.

DAMAGING WINDS AND LARGE HAIL ARE LIKELY.  GO INSIDE A STURDY
BUILDING AND STAY AWAY FROM WINDOWS.

A TORNADO WATCH IS IN EFFECT.  SEVERE THUNDERSTORMS CAN PRODUCE
TORNADOES.

HOWIESON

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 1, 7:26 PM CDT	Severe Thunderstorm Warning	MPX	Anoka, Isanti	64 min
Jul 1, 7:26 PM CDT	Severe Thunderstorm Warning	MPX	Ramsey	64 min
Jul 1, 7:33 PM CDT	Severe Thunderstorm Warning	MPX	McLeod, Wright	42 min
Jul 1, 7:53 PM CDT	Severe Thunderstorm Warning	MPX	Carver, Sibley	37 min
Jul 1, 7:53 PM CDT	Severe Thunderstorm Warning	MPX	Hennepin	37 min
Jul 1, 7:56 PM CDT	Severe Thunderstorm Warning	MPX	Dakota, Scott	64 min
Jul 1, 8:01 PM CDT	Tornado Warning	MPX	Anoka	29 min
Jul 1, 8:14 PM CDT	Tornado Warning	MPX	Isanti	46 min
Jul 1, 8:48 PM CDT	Severe Thunderstorm Warning	MPX	Goodhue	57 min
Jul 1, 8:56 PM CDT	Severe Thunderstorm Warning	MPX	Dakota	34 min
Jul 1, 9:23 PM CDT	Tornado Warning	MPX	Renville, Yellow Medicine	27 min
Jul 1, 9:47 PM CDT	Severe Thunderstorm Warning	MPX	Goodhue	28 min
Jul 1, 9:51 PM CDT	Tornado Warning	MPX	Kandiyohi, Renville	29 min
Jul 1, 10:17 PM CDT	Tornado Warning	MPX	Meeker	43 min
Jul 1, 10:30 PM CDT	Severe Thunderstorm Warning	MPX	Washington	35 min
Jul 1, 11:43 PM CDT	Severe Thunderstorm Warning	MPX	Rice	32 min

Nearby

Severe Thunderstorm Warnings in Minnesota, 1997 Every severe thunderstorm warning in 1997

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; radar from the NEXRAD Level II archive.