SPC MD 1475
MD 1475 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR EASTERN IOWA INTO SOUTHERN WISCONSIN AND NORTHERN ILLINOIS

Mesoscale Discussion 1475
NWS Storm Prediction Center Norman OK
0505 PM CDT Fri Jul 03 2026

Areas affected...Eastern Iowa into southern Wisconsin and northern
Illinois

Concerning...Severe potential...Watch possible 

Valid 032205Z - 040000Z

Probability of Watch Issuance...40 percent

SUMMARY...Convective trends are being monitored across eastern Iowa
into southern Wisconsin and northern Illinois. Watch issuance is
possible if further convective intensification and clustering can
occur in the coming hours.

DISCUSSION...Weak convection has been percolating along a residual
outflow boundary across eastern IA and into southern WI/northwest IL
over the past hour. Despite temperatures warming back into the 80s
and dewpoints recovering into the 70s, prior convective overturning
appears to be limiting the overall thermodynamic environment across
this region, resulting in the anemic convective development observed
so far. 

Further south, a more diffuse outflow boundary associated with a
weak MCS currently over Lower MI is beginning to advance northward.
Convective development in proximity to the boundary as well as
notable boundary-layer cumulus along/south of the boundary hint that
this demarcates the northern extent of the more buoyant/unstable air
mass (characterized by MLCAPE values of 2000-3000 J/kg). It remains
unclear how far north this boundary will progress through
mid-evening, but it is conceivable that the more buoyant air mass
will continue to spread north, eventually reaching the boundary
draped across eastern IA and the IL/WI border. If this occurs,
further intensification of convection will be possible, and
downstream propagation across northern IL may occur. It is also
possible that developing convection along the southern boundary
continues to intensify and could pose a more transient and localized
hail/wind risk in the coming hours. Confidence in either scenario is
relatively limited, but trends are being monitored for the need for
watch issuance this evening.

..Moore/Gleason.. 07/03/2026

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

ATTN...WFO...LOT...ILX...MKX...DVN...ARX...

LAT...LON   41088825 41078973 41179094 41489178 41769188 42279196
            42659190 43009168 43149140 43189071 43138795 43018777
            42768776 42338776 42068761 41808743 41738743 41558740
            41258749 41108776 41088825 

MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN

Read more
https://www.spc.noaa.gov/products/md/md1475.html