Alert archive / Minnesota / Mesoscale Discussions in 2004

Mesoscale Discussion 1920

August 8, 200416 counties in Iowa; 25 counties in Minnesota; 5 counties in Wisconsin

The Storm Prediction Center issued this mesoscale discussion at Aug 8, 2004, 12:17 PM CDT for 16 counties in Iowa; 25 counties in Minnesota; 5 counties in Wisconsin. It was in force for 58 min.

The area

The outline as issued.

The facts

Issued
Aug 8, 2004, 12:17 PM CDT (17:17 UTC)
Expired
Aug 8, 2004, 1:15 PM CDT
In force
58 min
Issued by
the Storm Prediction Center
All 46 counties

Cerro Gordo County, IA, Clay County, IA, Dickinson County, IA, Emmet County, IA, Floyd County, IA, Franklin County, IA, Hancock County, IA, Humboldt County, IA, Kossuth County, IA, Mitchell County, IA, O'Brien County, IA, Palo Alto County, IA, Pocahontas County, IA, Winnebago County, IA, Worth County, IA, Wright County, IA, Anoka County, MN, Blue Earth County, MN, Carver County, MN, Dakota County, MN, Dodge County, MN, Faribault County, MN, Freeborn County, MN, Goodhue County, MN, Hennepin County, MN, Jackson County, MN, Le Sueur County, MN, Martin County, MN, Mower County, MN, Nicollet County, MN, Olmsted County, MN, Ramsey County, MN, Rice County, MN, Scott County, MN, Sibley County, MN, Steele County, MN, Wabasha County, MN, Waseca County, MN, Washington County, MN, Watonwan County, MN, Wright County, MN, Buffalo County, WI, Dunn County, WI, Pepin County, WI, Pierce County, WI, Saint Croix County, WI

The radar

The Minneapolis radar (KMPX), 112 km from the middle of the area, began a volume at 17:16 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 nearest sounding before it

Minneapolis, MN (KMPX), launched 12:00Z, 5.3 hours before the alert went out and 111 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 2004-08-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 362 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 12:00Z on 2004-08-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 61 square meters per square second.1939Sfc1 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
362 J/kg
Mixed-layer CIN
-202 J/kg
Mixed-layer LCL
1170 m above ground
0-6 km bulk shear
17 kt
0-1 km storm-relative helicity
61 m²/s²
0-3 km storm-relative helicity
123 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.

082 
ACUS11 KWNS 081718
SWOMCD
SPC MCD 081717 
WIZ000-MNZ000-IAZ000-081815-

MESOSCALE DISCUSSION 1920
NWS STORM PREDICTION CENTER NORMAN OK
1217 PM CDT SUN AUG 08 2004

AREAS AFFECTED...PORTIONS OF SERN MN...WRN WI AND NRN IA

CONCERNING...SEVERE THUNDERSTORM POTENTIAL 

VALID 081717Z - 081815Z

MONITORING PORTIONS OF SERN MN...WRN WI AND NRN IA FOR A POSSIBLE WW
WITHIN THE NEXT HOUR OR SO. 

AT 17Z...A SURFACE TROUGH EXTENDED FROM NEAR STC TO 30 E RWF TO 50
SE FSD.  AIR MASS HAS DESTABILIZED WITH MLCAPES FROM 1000-1500 J/KG
...AND SHOULD DESTABILIZE FURTHER WITH ADDITIONAL HEATING. A FEW
ELEVATED STORMS ARE LOCATED ALONG THE SURFACE TROUGH ABOUT 30 SE
RWF. HOWEVER...AS TEMPERATURES WARM INTO THE LOWER 80S...THE CAPPING
INVERSION IS EXPECTED TO WEAKEN AND SURFACE BASED STORMS SHOULD 
DEVELOP ALONG AND AHEAD OF THE SURFACE TROUGH. MODERATE INSTABILITY
AND DEEP LAYER SHEAR OF 25-30 KT MAY BE SUFFICIENT FOR STORMS WITH
SEVERE HAIL AND SOME WIND DAMAGE.

..IMY.. 08/08/2004

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

ATTN...WFO...ARX...MPX...DMX...FSD...

42979583 43319568 44229444 45099404 45359391 45509251
44739141 42549306 42489424

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 8, 1:05 PM CDTMesoscale DiscussionSPCFremont, Harrison, Mills, Montgomery, Page, Pottawattamie55 min
Aug 8, 12:37 PM CDTMesoscale DiscussionSPCBecker, Clay, Douglas, Grant, Kittson, Mahnomen and 8 more83 min
Aug 8, 12:55 PM CDTSevere Thunderstorm WatchSPCBecker, Clay, Kittson, Mahnomen, Marshall, Norman and 5 more5 hr
Aug 8, 4:02 PM CDTMesoscale DiscussionSPCBecker, Beltrami, Cass, Clay, Clearwater, Hubbard and 11 more88 min
Aug 8, 4:35 PM CDTSevere Thunderstorm WatchSPCBecker, Beltrami, Cass, Clay, Clearwater, Crow Wing and 17 more5 hr
Aug 8, 5:03 PM CDTMesoscale DiscussionSPCAnoka, Benton, Blue Earth, Carver, Chisago, Dakota and 31 more117 min
Aug 8, 5:20 PM CDTSevere Thunderstorm WatchSPCAnoka, Benton, Brown, Carver, Chisago, Dakota and 21 more7 hr

Nearby

Mesoscale Discussions in Minnesota, 2004Mesoscale Discussions in Iowa, 2004Mesoscale Discussions in Wisconsin, 2004Every mesoscale discussion in 2004

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.