Alert archive / Minnesota / Tornado Warnings in 1999

Tornado Warning 15, NWS Twin Cities, MN

July 9, 1999Chisago County, Isanti County, Minnesota

NWS Twin Cities, MN issued this tornado warning at Jul 9, 1999, 1:12 PM CDT for Chisago County, Isanti County, Minnesota. It was in force for 33 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
Jul 9, 1999, 1:12 PM CDT (18:12 UTC)
Expired
Jul 9, 1999, 1:45 PM CDT
In force
33 min
Issued by
NWS Twin Cities, MN
Area
Whole counties

Counties Chisago County, MN, Isanti County, MN

The radar

The Minneapolis radar (KMPX), 84 km from the middle of the area, began a volume at 18:14 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.

The nearest sounding before it

Minneapolis, MN (KMPX), launched 12:00Z, 6.2 hours before the alert went out and 85 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, Minneapolis, MN at 12:00Z on 1999-07-09Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Minneapolis, MN at 12:00Z on 1999-07-09The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -56 square meters per square second.1939587897117Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1951 m above ground
0-6 km bulk shear
71 kt
0-1 km storm-relative helicity
-56 m²/s²
0-3 km storm-relative helicity
-22 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.

000 
TTAA00 KMSP 091813 RRA
TORMSP
MNC025-059-091845-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
112 PM CDT FRI JUL 9 1999

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

* TORNADO WARNING FOR...
  CHISAGO COUNTY IN EAST CENTRAL MINNESOTA
  ISANTI COUNTY IN EAST CENTRAL MINNESOTA
  
* UNTIL 145 PM CDT

* AT 110 PM CDT...DOPPLER RADAR DETECTED A POSSIBLE TORNADO 6 MILES
  SOUTHEAST OF MORA MI*NNESOTA.  THE STORM WAS MOVING SOUTHEAST AT 35
  MPH.

* SOME LOCATIONS AFFECTED
  BRAHAM
  HARRIS
  RUSH CITY
  NORTH BRANCH


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

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 9, 12:42 PM CDTTornado WarningMPXChisago33 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; radar from the NEXRAD Level II archive.