Alert archive / Minnesota / Tornado Warnings in 1999

Tornado Warning 1, NWS Twin Cities, MN

May 10, 1999Isanti County, Sherburne County, Minnesota

NWS Twin Cities, MN issued this tornado warning at May 10, 1999, 8:59 PM CDT for Isanti County, Sherburne County, Minnesota. It was in force for 36 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
May 10, 1999, 8:59 PM CDT (01:59 UTC)
Expired
May 10, 1999, 9:35 PM CDT
In force
36 min
Issued by
NWS Twin Cities, MN
Area
Whole counties

Counties Isanti County, MN, Sherburne County, MN

The nearest sounding before it

International Fa, MN (KINL), launched 00:00Z, 2.0 hours before the alert went out and 341 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 1999-05-11Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1 joules per kilogram.LCLEL10008507005003002001001 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 1999-05-11The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 252 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
1 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
504 m above ground
0-6 km bulk shear
23 kt
0-1 km storm-relative helicity
252 m²/s²
0-3 km storm-relative helicity
454 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

999 
WFUS1 KMSP 110158 RRA
TORMSP
MNC059-141-110235-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
859 PM CDT MON MAY 10 1999

THE NATIONAL WEATHER SERVICE IN THE TWIN CITIES/CHANHASSEN HAS
ISSUED A

* TORNADO WARNING FOR...
  SOUTHWESTERN ISANTI COUNTY IN EAST CENTRAL MINNESOTA
  EASTERN SHERBURNE COUNTY IN CENTRAL MINNESOTA

* UNTIL 935 PM CDT

* AT 857 PM CDT...LAW ENFORCEMENT REPORTED A TORNADO NEAR
  ZIMMERMAN...OR ABOUT 5 MILES NORTH OF ELK RIVER.  THE STORM WAS
  MOVING NORTH-NORTHEAST AT 30 MPH.

* SOME LOCATIONS AFFECTED
  SPENCER BROOK
  WEST POINT
  PINE BROOK
  AREAS NORTHEAST OF ZIMMERMAN


GO TO THE BASEMENT OR A SMALL INTERIOR ROOM ON THE LOWEST FLOOR
TDK


&

The office that day

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

IssuedProductOfficeCountiesLasted
May 10, 7:22 PM CDTSevere Thunderstorm WarningMPXAnoka, Hennepin38 min

Nearby

Tornado Warnings in Minnesota, 1999Every tornado warning in 1999Tornadoes in 1999

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.