Alert archive / Minnesota / Severe Thunderstorm Warnings in 2012

Severe Thunderstorm Warning 77, NWS Twin Cities, MN

May 19, 20126 counties in Minnesota; Polk County, Wisconsin

NWS Twin Cities, MN issued this severe thunderstorm warning at May 19, 2012, 7:31 PM CDT for 6 counties in Minnesota; Polk County, Wisconsin. It was in force for 59 min. 5 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
May 19, 2012, 7:31 PM CDT (00:31 UTC)
Expired
May 19, 2012, 8:30 PM CDT
In force
59 min
Issued by
NWS Twin Cities, MN
Area
Storm-based polygon
Hail
1.0 in
Wind
50.0 mph

Counties Anoka County, MN, Chisago County, MN, Dakota County, MN, Hennepin County, MN, Ramsey County, MN, Washington County, MN, Polk County, WI

The radar

The Minneapolis radar (KMPX), 63 km from the middle of the area, began a volume at 00:35 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 19, 7:34 PM CDTHAIL 15 Sw St Paul, MN
May 19, 7:35 PM CDTHAIL 1.75St Paul, MNWESTERN ST. PAUL
May 19, 7:38 PM CDTHAIL 0.882 Nw St Paul, MN
May 19, 7:40 PM CDTHAIL 0.751 Wsw St Paul, MN
May 19, 7:52 PM CDTHAIL 0.88St Paul, MNONE BLOCK NORTHWEST OF CAPITAL.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 0.5 hours before the alert went out and 65 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 2012-05-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1062 joules per kilogram.LCLLFCEL10008507005003002001001 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 00:00Z on 2012-05-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 139 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
1062 J/kg
Mixed-layer CIN
-23 J/kg
Mixed-layer LCL
2089 m above ground
0-6 km bulk shear
27 kt
0-1 km storm-relative helicity
139 m²/s²
0-3 km storm-relative helicity
188 m²/s²
Significant tornado parameter
0.0
Supercell composite
4.6

Open this sounding in Storm Lab

The text

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

975 
WUUS53 KMPX 200031
SVRMPX
MNC003-025-037-053-123-163-WIC095-200130-
/O.NEW.KMPX.SV.W.0077.120520T0031Z-120520T0130Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
731 PM CDT SAT MAY 19 2012

THE NATIONAL WEATHER SERVICE IN THE TWIN CITIES HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  EASTERN ANOKA COUNTY IN EAST CENTRAL MINNESOTA...
  SOUTHEASTERN CHISAGO COUNTY IN EAST CENTRAL MINNESOTA...
  NORTH CENTRAL DAKOTA COUNTY IN EAST CENTRAL MINNESOTA...
  EXTREME SOUTHEASTERN HENNEPIN COUNTY IN EAST CENTRAL MINNESOTA...
  RAMSEY COUNTY IN EAST CENTRAL MINNESOTA...
  WASHINGTON COUNTY IN EAST CENTRAL MINNESOTA...
  SOUTHWESTERN POLK COUNTY IN NORTHWEST WISCONSIN...

* UNTIL 830 PM CDT

* AT 730 PM CDT...RADAR INDICATED A SEVERE THUNDERSTORM...CAPABLE OF
  PRODUCING QUARTER SIZE HAIL. THIS STORM WAS LOCATED NEAR
  MAHTOMEDI...OR ABOUT 12 MILES NORTHEAST OF ST PAUL...AND MOVING
  NORTHEAST AT 35 MPH.

LOCATIONS IN THE WARNING INCLUDE...
  ST PAUL...
  FOREST LAKE...
  MAHTOMEDI...
  WILLERNIE...
  WHITE BEAR LAKE...
  NORTH OAKS...
  NORTH ST PAUL...
  VADNAIS HEIGHTS...
  LINO LAKES...
  LAKE ELMO...
  OAKDALE...
  MAPLEWOOD...
  LITTLE CANADA...
  SHOREVIEW...

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4537 9267 4521 9270 4520 9277 4511 9274
      4508 9280 4505 9280 4503 9276 4496 9276
      4482 9279 4469 9285 4477 9306 4487 9324
      4540 9302
TIME...MOT...LOC 0032Z 217DEG 30KT 4510 9296
WIND...HAIL <50MPH 1.00IN

$$

The office that day

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

IssuedProductOfficeCountiesLasted
May 19, 7:05 PM CDTSevere Thunderstorm WarningMPXChisago, Isanti55 min
May 19, 7:05 PM CDTSevere Thunderstorm WarningMPXDakota, Hennepin, Rice, Scott40 min
May 19, 7:51 PM CDTSevere Thunderstorm WarningMPXDakota, Hennepin, Scott38 min
May 19, 8:06 PM CDTAreal Flood AdvisoryMPXDakota, Hennepin, Ramsey, Scott3 hr
May 19, 8:52 PM CDTSpecial Weather StatementMPXBrown, Nicollet, Sibley, Watonwan38 min
May 20, 1:10 AM CDTSpecial Weather StatementMPXBenton, Mille Lacs50 min
May 20, 1:43 AM CDTSpecial Weather StatementMPXAnoka, Chisago, Isanti, Ramsey, Washington47 min
May 19, 7:42 PM CDTSevere Thunderstorm WarningMPXPolk, Saint Croix63 min
May 20, 12:38 PM CDTSpecial Weather StatementMPXEau Claire52 min

Nearby

Severe Thunderstorm Warnings in Minnesota, 2012Severe Thunderstorm Warnings in Wisconsin, 2012Every severe thunderstorm warning in 2012

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.