Alert archive / Minnesota / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 199, NWS Twin Cities, MN

July 30, 2011Isanti County, Minnesota

NWS Twin Cities, MN issued this severe thunderstorm warning at Jul 30, 2011, 8:50 PM CDT for Isanti County, Minnesota. It was in force for 55 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jul 30, 2011, 8:50 PM CDT (01:50 UTC)
Expired
Jul 30, 2011, 9:45 PM CDT
In force
55 min
Issued by
NWS Twin Cities, MN
Area
Storm-based polygon
Hail
1.25 in
Wind
70.0 mph

County Isanti County, MN

The radar

The Minneapolis radar (KMPX), 76 km from the middle of the area, began a volume at 01:54 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 watch it was issued in

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

IssuedProductOfficeLasted
Jul 30, 5:31 PM CDTSevere Thunderstorm WatchSPC7 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 1.8 hours before the alert went out and 77 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 00:00Z on 2011-07-31Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 2387 joules per kilogram.LCLLFCEL10008507005003002001001 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 00:00Z on 2011-07-31The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 58 square meters per square second.19395878Sfc1 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
2387 J/kg
Mixed-layer CIN
-23 J/kg
Mixed-layer LCL
1239 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
58 m²/s²
0-3 km storm-relative helicity
176 m²/s²
Significant tornado parameter
0.8
Supercell composite
8.4

Open this sounding in Storm Lab

The text

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

792 
WUUS53 KMPX 310150
SVRMPX
MNC059-310245-
/O.NEW.KMPX.SV.W.0199.110731T0150Z-110731T0245Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
850 PM CDT SAT JUL 30 2011

THE NATIONAL WEATHER SERVICE IN THE TWIN CITIES HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  SOUTHERN ISANTI COUNTY IN EAST CENTRAL MINNESOTA...

* UNTIL 945 PM CDT

* AT 849 PM CDT...RADAR INDICATED A SEVERE THUNDERSTORM...CAPABLE OF
  PRODUCING HALF DOLLAR SIZE HAIL AND WINDS UP TO 70 MPH. THIS STORM
  WAS LOCATED NEAR DALBO...OR ABOUT 9 MILES NORTHEAST OF PRINCETON...
  AND MOVING SOUTHEAST AT 20 MPH.

LOCATIONS IN THE WARNING INCLUDE...
  BODUM...
  ISANTI...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

IF YOU ARE IN THE PATH OF THIS STORM...PREPARE IMMEDIATELY FOR
DAMAGING WINDS IN EXCESS OF 60 MPH AND LARGE HAIL. SEEK SHELTER NOW
INSIDE A STURDY STRUCTURE AND STAY AWAY FROM WINDOWS.

THIS STORM HAS A HISTORY OF PRODUCING DESTRUCTIVE WINDS AND LARGE
DAMAGING HAIL. SEEK SHELTER NOW INSIDE A STURDY STRUCTURE AND STAY
AWAY FROM WINDOWS!

&&

LAT...LON 4550 9303 4549 9302 4541 9302 4542 9303
      4542 9350 4542 9351 4556 9351 4556 9303
TIME...MOT...LOC 0150Z 327DEG 16KT 4566 9345
WIND...HAIL 70MPH 1.25IN

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 30, 7:10 PM CDTTornado WarningMPXTodd50 min
Jul 30, 7:15 PM CDTSevere Thunderstorm WarningMPXDouglas30 min
Jul 30, 7:28 PM CDTAreal Flood AdvisoryMPXTodd3 hr
Jul 30, 7:42 PM CDTSevere Thunderstorm WarningMPXTodd63 min
Jul 30, 7:45 PM CDTSevere Thunderstorm WarningMPXKanabec45 min
Jul 30, 8:01 PM CDTSevere Thunderstorm WarningMPXKanabec, Mille Lacs29 min
Jul 30, 8:15 PM CDTSevere Thunderstorm WarningMPXStearns60 min
Jul 30, 8:18 PM CDTSevere Thunderstorm WarningMPXIsanti, Kanabec, Mille Lacs72 min
Jul 30, 8:22 PM CDTTornado WarningMPXIsanti, Kanabec, Mille Lacs38 min
Jul 30, 8:53 PM CDTTornado WarningMPXIsanti35 min
Jul 30, 8:56 PM CDTAreal Flood AdvisoryMPXAnoka, Isanti, Kanabec, Mille Lacs, Sherburne6 hr
Jul 30, 9:07 PM CDTSevere Thunderstorm WarningMPXKandiyohi, Meeker, Stearns38 min
Jul 30, 9:20 PM CDTSevere Thunderstorm WarningMPXAnoka55 min
Jul 30, 9:48 PM CDTSpecial Weather StatementMPXMcLeod, Meeker42 min
Jul 30, 9:50 PM CDTSevere Thunderstorm WarningMPXRamsey, Washington55 min
Jul 30, 9:54 PM CDTAreal Flood AdvisoryMPXAnoka, Dakota, Hennepin, Ramsey, Washington6 hr
Jul 30, 10:21 PM CDTSevere Thunderstorm WarningMPXAnoka39 min
Jul 30, 11:20 PM CDTSpecial Weather StatementMPXLe Sueur40 min
Jul 30, 11:26 PM CDTSevere Thunderstorm WarningMPXLe Sueur, Scott, Sibley31 min
Jul 30, 11:32 PM CDTSpecial Weather StatementMPXGoodhue43 min
Jul 30, 11:55 PM CDTSevere Thunderstorm WarningMPXGoodhue35 min
Jul 31, 4:00 PM CDTHeat AdvisoryMPXAnoka, Blue Earth, Brown, Carver, Chippewa, Dakota and 29 more28 hr

Nearby

Severe Thunderstorm Warnings in Minnesota, 2011Every severe thunderstorm warning in 2011

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.