Skip Navigation Links 
NOAA logo-Select to go to the NOAA homepage NOAA's National Weather Service   Select to go to the NWS homepage
Storm Prediction Center
navigation bar left  
  navigation bar end cap is the U.S. Government's official Web portal to all Federal, state and local government Web resources and services.

Mesoscale Discussion 990
< Previous MD         Next MD >
MD 990 graphic

   Mesoscale Discussion 0990
   NWS Storm Prediction Center Norman OK
   0620 PM CDT Sun Jun 11 2017

   Areas affected...Southeast MN...central and northern WI...and part
   of southern Upper MI

   Concerning...Severe potential...Watch possible 

   Valid 112320Z - 120145Z

   Probability of Watch Issuance...40 percent

   SUMMARY...Thunderstorms will continue to develop this evening across
   parts of southeast MN into west-central WI, with hail and strong
   wind gusts being the primary threats.  The wind threat will be
   greatest if storm mergers/cold pool formation occurs and activity
   spreads to the south/southeast.  A conditional tornado threat cannot
   be ruled out in vicinity of a west-east stationary/warm front
   extending from Goodhue/Wabasha Counties MN to Marathon/Wood Counties

   DISCUSSION...Strong southerly low-level flow and clearing skies
   across southeast MN into west-central/central WI in the wake of the
   early day MCS (that was currently moving east of northern Lower MI)
   has resulted in sufficient theta-e advection across southeast MN
   through WI for robust destabilization.  Objective analyses indicated
   mixed-layer CAPE of 2000-2500 J/kg extending from southern MN to
   central WI, situated in vicinity of an outflow-reinforced baroclinic
   zone and 1000-1500 J/kg of MUCAPE extending into northern WI near a
   southwest to east-northeast oriented outflow boundary.  Meanwhile,
   modified 12Z DVN/16Z GRB soundings for southeast MN/western WI
   surface observations suggested mixed-layer CAPE close to 3000 J/kg. 
   In addition to ongoing storms across northern WI, storms were also
   developing attendant to an eastward-moving northeast-southwest
   oriented outflow that extended from Barron County WI to southern
   Goodhue County MN to Kossuth County IA at 2305Z.

   Strong 850-700-mb layer warm advection across southeast MN and much
   of central and northern WI will support additional strong to severe
   storms this evening, with the available instability and strong bulk
   shear supporting both hail and strong wind gusts.  A concern for a
   tornado threat exists in vicinity of the west-east oriented
   baroclinic zone, extending from Goodhue/Wabasha Counties MN to
   central WI (eastward to Marathon/Wood Counties), where low-level
   shear is maximized (effective SRH of 300-400 m2/s2 per objective
   analyses).  Storms interacting with this boundary should have the
   greatest conditional probability for a tornado to form.

   ..Peters/Edwards.. 06/11/2017

   ...Please see for graphic product...


   LAT...LON   44009309 44919310 45559327 45929249 46109082 46228923
               46188839 46058800 45728794 44198974 44029004 44009051
               43859117 43839271 44009309 

Top/All Mesoscale Discussions/Forecast Products/Home
Weather Topics:
Watches, Mesoscale Discussions, Outlooks, Fire Weather, All Products, Contact Us

NOAA / National Weather Service
National Centers for Environmental Prediction
Storm Prediction Center
120 David L. Boren Blvd.
Norman, OK 73072 U.S.A.
Page last modified: June 12, 2017
Information Quality
Privacy Policy
Freedom of Information Act (FOIA)
About Us
Career Opportunities