Alert archive / Minnesota / Severe Thunderstorm Warnings in 1999

Severe Thunderstorm Warning 3, NWS Twin Cities, MN

May 10, 1999Anoka County, Hennepin County, Minnesota

NWS Twin Cities, MN issued this severe thunderstorm warning at May 10, 1999, 6:31 PM CDT for Anoka County, Hennepin County, Minnesota. It was in force for 29 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
May 10, 1999, 6:31 PM CDT (23:31 UTC)
Expired
May 10, 1999, 7:00 PM CDT
In force
29 min
Issued by
NWS Twin Cities, MN
Area
Whole counties

Counties Anoka County, MN, Hennepin County, MN

The radar

The Minneapolis radar (KMPX), 36 km from the middle of the area, began a volume at 23:13 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

TimeReportWhereRemark
May 10, 6:31 PM CDTThunderstorm Wind 58Crystal, MNNumerous Large Trees felled. Auto and Home damaged. Fifteen thousand residents were leftwithout power for several hours.
May 10, 6:35 PM CDTThunderstorm Wind 56Brooklyn Park, MNTrees Down. Wind Speed Estimated.

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 nearest sounding before it

Minneapolis, MN (KMPX), launched 12:00Z, 11.5 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-pSkew-T log-p diagram, Minneapolis, MN at 12:00Z on 1999-05-10Temperature 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°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Minneapolis, MN at 12:00Z on 1999-05-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 372 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
1064 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
372 m²/s²
0-3 km storm-relative helicity
386 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 
WUUS1 KMSP 102334 RRA
SVRMSP
MNC003-053-110000-

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

THE NATIONAL WEATHER SERVICE IN THE TWIN CITIES HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  ANOKA COUNTY IN EAST CENTRAL MINNESOTA
  NORTHERN HENNEPIN COUNTY IN EAST CENTRAL MINNESOTA

* UNTIL 700 PM CDT

* AT 631 PM CDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM WITH DAMAGING WINDS OVER BROOKLYN CENTER...OR
  ABOUT 9 MILES NORTH OF MINNEAPOLIS...MOVING NORTH AT 50 MPH.

* SOME LOCATIONS AFFECTED BY THIS STORM INCLUDE...
  EAST BETHEL
  COON RAPIDS
  BROOKLYN PARK
  BLAINE
  CRYSTALL

THIS IS A DANGEROUS STORM...STAY INDOORS AWAY FROM WINDOWS. THIS 
STORM HAS BLOWN DOWN TREES IN GOLDEN VALLEY AND CRYSTAL.

The office that day

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

IssuedProductOfficeCountiesLasted
May 10, 6:04 AM CDTSevere Thunderstorm WarningMPXKandiyohi41 min

Nearby

Severe Thunderstorm Warnings in Minnesota, 1999Every severe thunderstorm warning 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; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.