Severe threat 6/10-6/12

[SchaumburgStormer]

Ok gents, keep me up to date with what’s happening locally, and I’ll keep you guys up to date on what’s happening in St Thomas. 

[A-L-E-K]

RIP Sycamore IL

[hawkeye_wx]

There are no flood watches out, yet, but the CAMs are all dumping several inches of rain across parts of the se IA, n IL, ne MO area.

[csnavywx]

3 hours ago, A-L-E-K said:

mesoanalysis showing over 4ksbcape in n il this afternoon

 

[Possum]

just finished staking all of my tomatoes here in chicago. ready for whatever may come.


.

[Chicago Storm]

we'll try again tomorrow...

[A-L-E-K]

Sad but true

[frostfern]

The SPC has all of western MI under the gun tomorrow evening, but the CAMs are split on how much late night crapvection interferes with returning instability.  None of the CAMs are exact on convective placement now so it’s up in the air.   

Hope I at least get a nice storm this evening if tomorrow turns out to be miss south stank.

[andyhb]

Parameter space near/south of that warm front in the backed surface winds tomorrow is alarming for any semi-discrete storms that can maintain themselves in the area. While there certainly are some caveats such as storm mode, degree of HP dominance given less than ideal venting flow and high PWATs, and prior convection, the high population and potential for relatively fast moving storms makes this likely the most dangerous setup so far this year on paper.

[Chinook]

The NWS is already putting out a few considerable severe thunderstorm warnings in Iowa/Illinois for 70mph wind gusts

[andyhb]

The 3 km NAM has a 100 kt 500 mb max tomorrow in IA, I cannot recall very many systems at all with that in June @RCNYILWX.

[ILSNOW]

 

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.

 

[Chicago Storm]

Numerous 70-90MPH wind reports in NE Iowa, NW Illinois and SW Wisconsin.

[nwohweather]

Numerous 70-90MPH wind reports in NE Iowa, NW Illinois and SW Wisconsin.

I’m shocked the forum isn’t buzzing more. That MCS is essentially a Cat 1 hurricane running thru Wisconsin right now

[Baum]

6 minutes ago, nwohweather said:

I’m shocked the forum isn’t buzzing more. That MCS is essentially a Cat 1 hurricane running thru Wisconsin right now

They can have the wind. I just want a quick shot of rain to cool things down so I can grill later.

[Chicago Storm]

2 hours ago, Chicago Storm said:

we'll try again tomorrow...

the reverse jinx worked.

[homedis]

Well that line escalated quickly in N IL. Curious to see if the winds intensify in this southern part of the MCS.

[SchaumburgStormer]

5 hours ago, SchaumburgStormer said:

Ok gents, keep me up to date with what’s happening locally, and I’ll keep you guys up to date on what’s happening in St Thomas. 

Narrator voice - “Hell of a line coming through Chicagoland, St Thomas with occasional clouds shading my beer” 

Nice to see us rocking and rolling back home. 

[Nelson]

Fairly impressive winds as things rolled through here. Nothing major, though. Happy to see some action. Some reports of 80mph+ gusts with that line before it got here but not sure we saw that at my location. I'm guessing more like 50-60mph

 

[frostfern]

6 minutes ago, homedis said:

Well that line escalated quickly in N IL. Curious to see if the winds intensify in this southern part of the MCS.

I’d expect it to briefly intensify as it gets closer to the lake, then gust out over the water.  The low level shear is not so great here in Michigan, but the CAPE will still be there for some pulses to be strong.

[pen_artist]

Might some convergence on the line as it approaches Elburn, IL area