ACUS11 KWNS 101800

SWOMCD

SPC MCD 101800 

WIZ000-ILZ000-IAZ000-MNZ000-102000-



Mesoscale Discussion 1066

NWS Storm Prediction Center Norman OK

0100 PM CDT Wed Jun 10 2026



Areas affected...southern Wisconsin and northern Illinois



Concerning...Severe Thunderstorm Watch 301...



Valid 101800Z - 102000Z



The severe weather threat for Severe Thunderstorm Watch 301

continues.



SUMMARY...An arcing line of thunderstorms has organized in eastern

Iowa and will move northeastward for the next few hours through WW

301. The threat for severe wind gusts is greatest in the delineated

area as the system moves through.



DISCUSSION...A line of severe thunderstorms has developed in eastern

IA and is moving northeastward into southern WI and northern IL. A

64-kt wind gust was reported at 1740z in Dubuque, IA associated with

this convection. Difluence aloft and low-level convergence along the

leading edge of a ~10-F-deficit cold pool have likely contributed to

storm strengthening during the last hour or so. Per current

mesoanalysis, the line of storms is moving into a CAPE axis

stretching from central IN northwestward into southeastern MN,

featuring 2500+ J/kg along the WI/IL border. Bulk shear magnitudes

are around 40 kts and southwesterly, oriented perpendicular to the

convective line. This environment will support a threat for

continued severe wind gusts as the system moves northeast for the

next few hours.



..Flournoy.. 06/10/2026



...Please see www.spc.noaa.gov for graphic product...



ATTN...WFO...GRB...LOT...MKX...DVN...ARX...



LAT...LON   42909185 43639117 44029026 44198911 43798795 42698784

            42008854 41379002 42289068 42909185 



MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH

MOST PROBABLE PEAK WIND GUST...65-80 MPH

MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN