SPC MD 1027

MD 1027 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF EASTERN IOWA INTO SOUTHWESTERN WISCONSIN AND NORTHERN ILLINOIS Mesoscale Discussion 1027 NWS Storm Prediction Center Norman OK 1258 PM CDT Mon Jun 08 2026 Areas affected...portions of eastern Iowa into southwestern Wisconsin and northern Illinois Concerning...Severe potential...Watch unlikely Valid 081758Z - 081930Z Probability of Watch Issuance...5 percent SUMMARY...Scattered thunderstorms will evolve northeastward through the afternoon today. A brief/weak tornado or landspout cannot be ruled out. DISCUSSION...Latest observations depict a well-defined MCV over east-central Iowa, with a weak surface reflection located near Iowa City, Iowa. A broken band of thunderstorms extends southeastward from this feature into east-central and southern Illinois, perhaps along a weak surface trough/wind shift. Regional VWPs (e.g., ILX/DVN) depict weakly-curved, low-level hodographs with ~50-75 m2/s2 0-1 km SRH within a very moist (dewpoints in the low/mid 70s F) and weakly unstable (MLCAPE 500 to locally 1500 J/kg) environment. Weak mid-level flow (less than 20-30 kts sampled by these VAD profiles) and effective shear less than 20 kts (per latest objective analysis) will limit overall storm organization and should largely preclude marginal supercell structures. Enhanced surface vertical vorticity, particularly in the vicinity of the weak surface low in eastern Iowa and, to a lesser extent, along the surface wind shift in Illinois, and modest low-level buoyancy (0-3 km CAPE up to 125 J/kg) may support some potential for a brief/weak landspout tornado, however. A localized strong wind gust (40-45 mph) also cannot be ruled out given the very moist environment. Watch issuance is not expected owing to the limited nature of this severe threat. ..Chalmers/Smith.. 06/08/2026 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LOT...ILX...MKX...DVN...ARX... LAT...LON 42289188 42649195 43139171 43479123 43449066 43198997 42738931 41538823 40998810 40658804 40438821 40298857 40318883 40598927 40828966 41049005 41089035 41039068 41069098 41199129 41489159 41949179 42289188 MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 90 MPH Read more