Alert archive / Minnesota / Mesoscale Discussions in 2012

Mesoscale Discussion 838

May 19, 201246 counties in Minnesota

The Storm Prediction Center issued this mesoscale discussion at May 19, 2012, 1:49 PM CDT for 46 counties in Minnesota. It was in force for 86 min.

The area

The outline as issued.

The facts

Issued: May 19, 2012, 1:49 PM CDT (18:49 UTC)
Expired: May 19, 2012, 3:15 PM CDT
In force: 86 min
Issued by: the Storm Prediction Center
Chance of a watch: 20%

All 46 counties

Aitkin County, MN, Anoka County, MN, Benton County, MN, Brown County, MN, Carlton County, MN, Carver County, MN, Cass County, MN, Chippewa County, MN, Chisago County, MN, Cottonwood County, MN, Crow Wing County, MN, Douglas County, MN, Hennepin County, MN, Hubbard County, MN, Isanti County, MN, Itasca County, MN, Jackson County, MN, Kanabec County, MN, Kandiyohi County, MN, Koochiching County, MN, Lake County, MN, Lyon County, MN, McLeod County, MN, Meeker County, MN, Mille Lacs County, MN, Morrison County, MN, Murray County, MN, Nicollet County, MN, Nobles County, MN, Pine County, MN, Pope County, MN, Ramsey County, MN, Redwood County, MN, Renville County, MN, Rock County, MN, Saint Louis County, MN, Scott County, MN, Sherburne County, MN, Sibley County, MN, Stearns County, MN, Swift County, MN, Todd County, MN, Wadena County, MN, Watonwan County, MN, Wright County, MN, Yellow Medicine County, MN

The radar

The Minneapolis radar (KMPX), 128 km from the middle of the area, began a volume at 18:49 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, 6.8 hours before the alert went out and 126 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 23 J/kg
Mixed-layer CIN: -352 J/kg
Mixed-layer LCL: 1615 m above ground
0-6 km bulk shear: 22 kt
0-1 km storm-relative helicity: 192 m²/s²
0-3 km storm-relative helicity: 147 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.

397 
ACUS11 KWNS 191849
SWOMCD
SPC MCD 191849 
MNZ000-WIZ000-192015-

MESOSCALE DISCUSSION 0838
NWS STORM PREDICTION CENTER NORMAN OK
0149 PM CDT SAT MAY 19 2012

AREAS AFFECTED...MUCH OF MN

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 

VALID 191849Z - 192015Z

PROBABILITY OF WATCH ISSUANCE...20 PERCENT

SUMMARY...SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP OVER
PORTIONS OF MN DURING THE NEXT FEW HRS. A FEW STORMS WILL POSE A
THREAT FOR DAMAGING WIND GUSTS AND LARGE HAIL. ALTHOUGH A WW DOES
NOT APPEAR LIKELY ATTM...TRENDS WILL CONTINUE TO BE MONITORED.

DISCUSSION...MESOANALYSIS AT 1830Z SHOWED A COLD FRONT EXTENDING
SWWD FROM N-CNTRL MN INTO EXTREME SERN SD. SURFACE TEMPERATURES
AHEAD OF THE FRONT WERE WARMING INTO THE 70S AND 80S...AND DEWPOINTS
WERE GENERALLY IN THE UPR 50S TO LOW 60S. THE WARM/MOIST BOUNDARY
LAYER COMBINED WITH MIDLEVEL LAPSE RATES NEAR 7 C/KM ARE AIDING IN
THE DEVELOPMENT OF MLCAPE VALUES NEAR 1000 J/KG. IN
ADDITION...SURFACE HEATING IS DESTABILIZING THE BOUNDARY LAYER AND
WEAKENING CINH. AS A RESULT...VISIBLE SATELLITE IMAGERY INDICATES
DEEPENING CUMULUS ALONG THE COLD FRONT...WITH ANOTHER AREA OF
CUMULUS GROWTH LIFTING NWD TOWARD NERN MN. GIVEN THESE
TRENDS...SCATTERED THUNDERSTORM DEVELOPMENT APPEARS PROBABLE DURING
THE NEXT FEW HRS. VWP/S AND RAP FORECAST SOUNDINGS SHOW A DEEP LAYER
OF S-SWLY FLOW RESIDES ACROSS THE REGION...WITH EFFECTIVE SHEAR
VALUES RANGING FROM 20-40 KT. THESE WIND PROFILES SHOULD FAVOR
MULTICELL CLUSTERS AND LINE SEGMENTS POSING A THREAT FOR ISOLATED
DAMAGING WIND GUSTS AND LARGE HAIL.

..GARNER/WEISS.. 05/19/2012

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

ATTN...WFO...DLH...MPX...FGF...FSD...

LAT...LON   43579632 46209537 48579465 48709274 47789121 45059304
            43549476 43579632

Nearby

Mesoscale Discussions in Minnesota, 2012 Every 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.