Alert archive / Minnesota / Severe Thunderstorm Warnings in 2011

Severe Thunderstorm Warning 233, NWS Twin Cities, MN

August 6, 2011Ramsey County, Washington County, Minnesota

NWS Twin Cities, MN issued this severe thunderstorm warning at Aug 6, 2011, 3:29 PM CDT for Ramsey County, Washington County, Minnesota. It was in force for 46 min. 1 report 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
Aug 6, 2011, 3:29 PM CDT (20:29 UTC)
Expired
Aug 6, 2011, 4:15 PM CDT
In force
46 min
Issued by
NWS Twin Cities, MN
Area
Storm-based polygon
Hail
1.25 in
Wind
50.0 mph

Counties Ramsey County, MN, Washington County, MN

The radar

The Minneapolis radar (KMPX), 64 km from the middle of the area, began a volume at 20:28 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
Aug 6, 3:30 PM CDTHAIL 0.254 Nne White Bear Lake, MN

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 12:00Z, 8.5 hours before the alert went out and 67 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 2011-08-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 690 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 12:00Z on 2011-08-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 41 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
690 J/kg
Mixed-layer CIN
-28 J/kg
Mixed-layer LCL
750 m above ground
0-6 km bulk shear
27 kt
0-1 km storm-relative helicity
41 m²/s²
0-3 km storm-relative helicity
51 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.6

Open this sounding in Storm Lab

The text

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

372 
WUUS53 KMPX 062029
SVRMPX
MNC123-163-062115-
/O.NEW.KMPX.SV.W.0233.110806T2029Z-110806T2115Z/

BULLETIN - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WARNING
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
329 PM CDT SAT AUG 6 2011

THE NATIONAL WEATHER SERVICE IN THE TWIN CITIES HAS ISSUED A

* SEVERE THUNDERSTORM WARNING FOR...
  EXTREME NORTHEASTERN RAMSEY COUNTY IN EAST CENTRAL MINNESOTA...    
  NORTHERN WASHINGTON COUNTY IN EAST CENTRAL MINNESOTA...

* UNTIL 415 PM CDT

* AT 329 PM CDT...RADAR INDICATED A SEVERE THUNDERSTORM...CAPABLE OF
  PRODUCING HALF DOLLAR SIZE HAIL. THIS STORM WAS LOCATED NEAR
  CENTERVILLE...OR ABOUT 10 MILES SOUTH OF FOREST LAKE...AND MOVING
  EAST AT 25 MPH.

LOCATIONS IN THE WARNING INCLUDE...
  HUGO...
  STILLWATER...
  MARINE ON ST CROIX...
  BAYPORT...

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.

REPORT ANY SIGNIFICANT WIND OR HAIL DAMAGE TO THE NEAREST LAW
ENFORCEMENT AGENCY...FOR RELAY TO THE NATIONAL WEATHER SERVICE.

&&

LAT...LON 4520 9277 4509 9276 4508 9280 4505 9280
      4503 9276 4502 9276 4501 9278 4508 9303
      4517 9302
TIME...MOT...LOC 2029Z 273DEG 20KT 4513 9298
WIND...HAIL <50MPH 1.25IN

$$
3 follow-up statements
900 
WWUS53 KMPX 062043
SVSMPX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
343 PM CDT SAT AUG 6 2011

MNC123-163-062115-
/O.CON.KMPX.SV.W.0233.000000T0000Z-110806T2115Z/
RAMSEY MN-WASHINGTON MN-
343 PM CDT SAT AUG 6 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR NORTHERN
WASHINGTON AND RAMSEY COUNTIES UNTIL 415 PM CDT...

AT 343 PM CDT...NATIONAL WEATHER SERVICE RADAR INDICATED A SEVERE
THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL.  THIS STORM WAS 
LOCATED NEAR HUGO...OR 11 MILES SOUTH OF FOREST LAKE...MOVING EAST 
SOUTHEAST AT 20 MPH.

LOCATIONS IMPACTED INCLUDE...
  STILLWATER...MARINE ON ST CROIX...BAYPORT AND OAK PARK HEIGHTS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 60 MILES PER
HOUR...LARGE HAIL...AND DEADLY LIGHTNING. FOR YOUR PROTECTION MOVE TO
AN INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR HOME OR BUSINESS.

TO REPORT SEVERE WEATHER...CONTACT YOUR NEAREST LAW ENFORCEMENT
AGENCY. THEY WILL RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE
IN THE TWIN CITIES.

&&

LAT...LON 4520 9277 4509 9276 4508 9280 4505 9280
      4503 9276 4502 9276 4501 9278 4508 9303
      4517 9302
TIME...MOT...LOC 2043Z 281DEG 19KT 4512 9293
WIND...HAIL <50MPH 1.00IN

$$
160 
WWUS53 KMPX 062056
SVSMPX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
356 PM CDT SAT AUG 6 2011

MNC123-062111-
/O.CAN.KMPX.SV.W.0233.000000T0000Z-110806T2115Z/
RAMSEY MN-
356 PM CDT SAT AUG 6 2011

...THE SEVERE THUNDERSTORM WARNING FOR EXTREME NORTHEASTERN RAMSEY 
COUNTY IS CANCELLED...

THE STORM WHICH PROMPTED THE WARNING HAS MOVED OUT OF EXTREME 
NORTHEASTERN RAMSEY COUNTY.

TO REPORT SEVERE WEATHER...CONTACT YOUR NEAREST LAW ENFORCEMENT
AGENCY. THEY WILL RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE
IN THE TWIN CITIES.

LAT...LON 4509 9276 4508 9280 4505 9280 4502 9276
      4501 9278 4507 9298 4512 9298 4513 9298
      4516 9277
TIME...MOT...LOC 2056Z 291DEG 16KT 4508 9292

$$

MNC163-062115-
/O.CON.KMPX.SV.W.0233.000000T0000Z-110806T2115Z/
WASHINGTON MN-
356 PM CDT SAT AUG 6 2011

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR CENTRAL
WASHINGTON COUNTY UNTIL 415 PM CDT...

AT 356 PM CDT...NATIONAL WEATHER SERVICE RADAR INDICATED A SEVERE
THUNDERSTORM CAPABLE OF PRODUCING QUARTER SIZE HAIL.  THIS STORM WAS
LOCATED NEAR MAHTOMEDI...OR 12 MILES NORTHEAST OF ST PAUL...MOVING
EAST AT 20 MPH.

LOCATIONS IMPACTED INCLUDE...
  STILLWATER...BAYPORT AND OAK PARK HEIGHTS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

SEVERE THUNDERSTORMS PRODUCE DAMAGING WIND IN EXCESS OF 60 MILES PER
HOUR...LARGE HAIL...AND DEADLY LIGHTNING. FOR YOUR PROTECTION MOVE TO
AN INTERIOR ROOM ON THE LOWEST FLOOR OF YOUR HOME OR BUSINESS.

TO REPORT SEVERE WEATHER...CONTACT YOUR NEAREST LAW ENFORCEMENT
AGENCY. THEY WILL RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE
IN THE TWIN CITIES.

&&

LAT...LON 4509 9276 4508 9280 4505 9280 4502 9276
      4501 9278 4507 9298 4512 9298 4513 9298
      4516 9277
TIME...MOT...LOC 2056Z 291DEG 16KT 4508 9292
WIND...HAIL <50MPH 1.00IN

$$
879 
WWUS53 KMPX 062109
SVSMPX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
409 PM CDT SAT AUG 6 2011

MNC163-062124-
/O.EXP.KMPX.SV.W.0233.000000T0000Z-110806T2115Z/
WASHINGTON MN-
409 PM CDT SAT AUG 6 2011

...THE SEVERE THUNDERSTORM WARNING FOR CENTRAL WASHINGTON COUNTY WILL
EXPIRE AT 415 PM CDT...

THE STORM WHICH PROMPTED THE WARNING HAS WEAKENED BELOW SEVERE
LIMITS...AND NO LONGER POSES AN IMMEDIATE THREAT TO LIFE OR 
PROPERTY. SCATTERED THUNDERSTORMS ARE STILL EXPECTED INTO THE 
EVENING HOURS ACROSS THE TWIN CITIES METRO AREA.

TO REPORT SEVERE WEATHER...CONTACT YOUR NEAREST LAW ENFORCEMENT
AGENCY. THEY WILL RELAY YOUR REPORT TO THE NATIONAL WEATHER SERVICE
IN THE TWIN CITIES.

LAT...LON 4509 9276 4508 9280 4505 9280 4502 9276
      4501 9278 4507 9298 4512 9298 4513 9298
      4516 9277
TIME...MOT...LOC 2109Z 291DEG 16KT 4506 9284

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 5, 10:55 PM CDTAreal Flood AdvisoryMPXKandiyohi, Meeker, Sherburne, Wright3 hr
Aug 6, 10:59 AM CDTAreal Flood AdvisoryMPXDouglas, Mille Lacs, Morrison, Todd4 hr
Aug 6, 11:59 AM CDTSpecial Weather StatementMPXMorrison61 min
Aug 6, 12:37 PM CDTSevere Thunderstorm WarningMPXBenton, Isanti, Kanabec, Mille Lacs, Morrison53 min
Aug 6, 1:20 PM CDTSevere Thunderstorm WarningMPXChisago, Isanti, Kanabec31 min
Aug 6, 2:35 PM CDTSpecial Weather StatementMPXAnoka25 min
Aug 6, 3:18 PM CDTSpecial Weather StatementMPXWashington27 min
Aug 6, 5:36 PM CDTSpecial Weather StatementMPXDouglas24 min
Aug 6, 6:59 PM CDTSpecial Weather StatementMPXStearns46 min

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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.