Alert archive / Minnesota / Mesoscale Discussions in 2012

Mesoscale Discussion 1202

June 17, 201224 counties in Minnesota; Pierce County, Polk County, Saint Croix County, Wisconsin

The Storm Prediction Center issued this mesoscale discussion at Jun 17, 2012, 7:27 PM CDT for 24 counties in Minnesota; Pierce County, Polk County, Saint Croix County, Wisconsin. It was in force for 93 min.

The area

The outline as issued.

The facts

Issued
Jun 17, 2012, 7:27 PM CDT (00:27 UTC)
Expired
Jun 17, 2012, 9:00 PM CDT
In force
93 min
Issued by
the Storm Prediction Center
All 27 counties

Anoka County, MN, Benton County, MN, Carver County, MN, Chippewa County, MN, Chisago County, MN, Dakota County, MN, Hennepin County, MN, Isanti County, MN, Kanabec County, MN, Kandiyohi County, MN, McLeod County, MN, Meeker County, MN, Mille Lacs County, MN, Morrison County, MN, Pope County, MN, Ramsey County, MN, Renville County, MN, Scott County, MN, Sherburne County, MN, Stearns County, MN, Swift County, MN, Todd County, MN, Washington County, MN, Wright County, MN, Pierce County, WI, Polk County, WI, Saint Croix County, WI

The radar

The Minneapolis radar (KMPX), 86 km from the middle of the area, began a volume at 00:30 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

The nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 0.5 hours before the alert went out and 84 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 2012-06-18Temperature 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 00:00Z on 2012-06-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 492 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
1837 m above ground
0-6 km bulk shear
41 kt
0-1 km storm-relative helicity
492 m²/s²
0-3 km storm-relative helicity
747 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.0

Open this sounding in Storm Lab

The text

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

494 
ACUS11 KWNS 180028
SWOMCD
SPC MCD 180027
WIZ000-MNZ000-180200-

MESOSCALE DISCUSSION 1202
NWS STORM PREDICTION CENTER NORMAN OK
0727 PM CDT SUN JUN 17 2012

AREAS AFFECTED...CENTRAL MINNESOTA INTO PARTS OF NORTHWESTERN
WISCONSIN

CONCERNING...TORNADO WATCH 404...

VALID 180027Z - 180200Z

THE SEVERE WEATHER THREAT FOR TORNADO WATCH 404 CONTINUES.

SUMMARY...A NEW WW LIKELY WILL BE NEEDED EAST OF WW 404 WITHIN THE
NEXT 1 TO 2 HOURS...FOR A CONTINUED RISK OF AT LEAST DAMAGING WIND
GUSTS AND HAIL INTO LATE EVENING.

DISCUSSION...LOWER/MID TROPOSPHERIC WARM ADVECTION CONTINUES TO
SUPPORT THE EVOLUTION OF AN ORGANIZED MESOSCALE SCALE CONVECTIVE
SYSTEM IN THE PRESENCE OF MODERATELY LARGE CAPE AND STRENGTHENING
DEEP LAYER MEAN FLOW AND SHEAR.  AS THE SOUTHWESTERLY 850 MB JET
STRENGTHENS TO 50+ KT ACROSS PARTS OF THE MID MISSOURI VALLEY INTO
THE UPPER MISSISSIPPI VALLEY THIS EVENING...AND SURFACE COLD POOLS
ASSOCIATED THE CONVECTION CONSOLIDATE AND DEEPEN...FORWARD
PROPAGATION MAY ACCELERATE...IN AN EASTERLY OR EAST SOUTHEASTERLY
DIRECTION ACROSS CENTRAL MINNESOTA THROUGH 01-03Z.  THE 00Z SOUNDING
FROM MINNEAPOLIS SUGGESTS SUFFICIENT DESTABILIZATION WILL OCCUR
ACROSS THE UPPER MISSISSIPPI VALLEY TO MAINTAIN A RISK FOR STRONG
WIND GUSTS AND HAIL ACROSS AREAS NEAR/WEST THROUGH NORTH OF
MINNEAPOLIS-ST. PAUL...INTO PARTS OF NORTHWESTERN WISCONSIN...
BEFORE ACTIVITY WEAKENS LATE THIS EVENING.

..KERR.. 06/18/2012

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...DLH...MPX...FGF...ABR...

LAT...LON   45849537 46259514 46219429 45969286 45439224 44929223
            44669240 44519309 44599446 44869569 45219627 45469593
            45519576 45849537

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 17, 7:20 PM CDTMesoscale DiscussionSPCKittson, Marshall85 min
Jun 17, 7:57 PM CDTSevere Thunderstorm WatchSPCAitkin, Anoka, Benton, Blue Earth, Brown, Carlton and 31 more8 hr
Jun 17, 10:55 PM CDTMesoscale DiscussionSPCCarver, Dakota, Dodge, Goodhue, Le Sueur, McLeod and 8 more95 min
Jun 18, 1:28 AM CDTMesoscale DiscussionSPCDakota, Dodge, Fillmore, Goodhue, Hennepin, Houston and 7 more62 min
Jun 18, 11:40 AM CDTMesoscale DiscussionSPCAdams, Brown, Buffalo, Calumet, Clark, Door and 27 more2 hr
Jun 18, 12:24 PM CDTSevere Thunderstorm WatchSPCAdams, Brown, Buffalo, Calumet, Clark, Door and 29 more8 hr
Jun 18, 2:49 PM CDTMesoscale DiscussionSPCBrown, Calumet, Kewaunee, Marinette, Menominee, Oconto and 5 more86 min
Jun 18, 3:50 PM CDTMesoscale DiscussionSPCDoor, Kewaunee85 min
Jun 18, 6:00 PM CDTMesoscale DiscussionSPCBrown, Calumet, Door, Green Lake, Kewaunee, Manitowoc and 7 more60 min

Nearby

Mesoscale Discussions in Minnesota, 2012Mesoscale Discussions in Wisconsin, 2012Every mesoscale discussion 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.