6/16-6/18 Severe Weather

[nvck]

Looking like another impactful stretch of weather coming up, with Wednesday, as of now, having the highest ceiling. StormNet, CSU-MLP, and other ML products have all had very "hot" runs lately, pretty eyecatching stuff, especially as the northern bound of the highest prob area is over the same area that saw several tornadoes on Thursday. The GEFS has been consistent in showing an area of high P[SCP>1] over portions of Missouri and Illinois, even back into Kansas, for multiple runs now, while other models expand the risk further east towards Ohio. Regardless, very strong flow for this time of the year will overlap an area of ample moisture. Should be an interesting couple days.

[andyhb]

As of right now, this looks like an outbreak over potentially a large expanse of real estate, with both strong tornadoes and a derecho possible. I’m amazed at how strong the LLJ is across many models right now.

[A-L-E-K]

Miss south for mby, glad to see IL staying hot tho

[nvck]

hoping we get some more of an east trend, am pretty tired of getting 2am weakening MCSs, would at least like to see some lightning in the daytime

[nvck]

More of a march/april look here than anything else, but loving the shear profile

[mjwise]

Nice baroclinic support so far into June with the GEFS, EPS, and AIFS ensemble means all showing a 992-995mb low traversing southern Lake Michigan late Wednesday.  Looks like most likely a cool rain for MBY. 

[CheeselandSkies]

I couldn't chase last Thursday due to being in Cleveland on a family trip (probably would have ended up on the still-tornadic relative junk in western IL anyway), but it'd be nice to have the target not be south of I-80 for once since I rarely can take PTO on short notice from my job.

[cyclone77]

Multiple models are showing a large MCS traversing Iowa again the morning of the event.  Will be interesting to see how the evolution of that affects the development later in the day.  

Very impressed by the synoptics of this.  Powerful upper jet knifing in with very impressive shear profiles over a wide area on the nose of that.

[andyhb]

The 12z Euro… holy moly.

[A-L-E-K]

Wagons north?

 

[Chicago916]

When all is said and done, Peoria to NWI gonna be the hot spot again. 

[nvck]

gonna go ahead and call a miss north/west here, and will hopefully be proven wrong

[A-L-E-K]

7 minutes ago, Chicago916 said:

When all is said and done, Peoria to NWI gonna be the hot spot again. 

Word, ready to comma head mcs tho

[cyclone77]

21 minutes ago, Chicago916 said:

When all is said and done, Peoria to NWI gonna be the hot spot again. 

Yep.  Might as well head towards Pontiac to Kankakee and camp out there until the event lol.

[Chambana]

1 hour ago, cyclone77 said:

Yep.  Might as well head towards Pontiac to Champaign and camp out there until the event lol.

Fyp 

[A-L-E-K]

 

 

[CheeselandSkies]

18Z NAM and RRFS-A (I know, I know, but they're the only mesoscale models that go out that far) edged a little bit north with the warm sector for Wednesday evening.

[Chinook]

I'm not even really sure how to process this potential day-4 threat (Wednesday.) The 500mb jet streak is much stronger than average, surface low pressure is lower than most pressure I've seen in June, other than hurricanes.

[MidwestChaser]

GFS seems to want to bring the WF into the Metro.

[Torchageddon]

29 minutes ago, Chinook said:

I'm not even really sure how to process this potential day-4 threat (Wednesday.) The 500mb jet streak is much stronger than average, surface low pressure is lower than most pressure I've seen in June, other than hurricanes.

The low starts off as 995mb near Alberta then deepens and stays <990mb for the rest of its trek zonally across the continent. I take it that is highly unusual.

[Jackstraw]

3 day 30% hatched right along the I70 corridor...

[A-L-E-K]

8 hours ago, MidwestChaser said:

GFS seems to want to bring the WF into the Metro.

 

I want 2 believe.jpeg

[nvck]

06z RRFS suggests that this may be more of a Thursday event for us, blowing up a cell right over the metro by midday. will be interesting to see what the 12z suite thinks, but I could see the d4 risk being shifted back west some

[metallica470]

1 hour ago, A-L-E-K said:

 

I want 2 believe.jpeg

And now StormNet went wagons south haha

[sbnwx85]

46 minutes ago, metallica470 said:

And now StormNet went wagons south haha

Lame

[A-L-E-K]

bummer but i'm ok with some comma head boomers and a miss south on the windy stuff

gonna boost our state tor numbers either way, looking to run away with the title in 2026?

[Jackstraw]

We usually get hit with these setups after sundown as they wane and have turned into basically windbags. Hard to get good sups this far east after April/early May. This may be the last chance before full on ridge riding shrimp season comes in around the 4th. There was a funnel cloud reported that I could've seen from my back porch with the last one (briefly touched down as an EF0 off to my east). Still a lot of if's. I'll have my bicycle ready lol

[A-L-E-K]

 

[mjwise]

12 hours ago, Torchageddon said:

The low starts off as 995mb near Alberta then deepens and stays <990mb for the rest of its trek zonally across the continent. I take it that is highly unusual.

According to this database (still seemingly updated), it would be record-breaking or nearly so for June once it gets into the lower GL region. Per the map below, record low pressure in June from Chicagoland into the central portion of the lower peninsula of michigan is ~992-993mb

https://www.wpc.ncep.noaa.gov/research/roth/SLPrecords.html

[nrgjeff]

Looks like a classic Illinois day on Wednesday. Parameters are high, and that could all go into a windstorm, but I have to favor supercells initially. So far looks like morning rain will scoot out and leave a lovely outflow boundary with which to work.

Factors that should get a big ol' bow echo going are WAA at 850 / 700 mb, 500 mb orientation / height falls, deepening sfc low, high instability, and an east-west boundary (outflow). That said, barring a quick mess, I'm thinking Illinois will book another tornado day.

Models line up with the morning rain pattern recognition. In this case looks like it gets away in plenty of time to reheat. Outflow boundary OFB will locally enhance low-level shear. Some of the soundings are little skinny, but that may be a result of temperature forecast uncertainty. Should be skinny north of the OFB, probably fatter south of it. Both sides the LI is robust. 

Should get supercells along both the synoptic boundary and outflow.  As usual we favor the boundary intersection. Also as usual, exact strategy will be a game time decision. Right on the intersection, or 1-2 cells east of it. Back on Thursday I believe the cyclical beast of the day was east of the main triple point, but on another differential heating boundary. 

Time will tell how Wednesday goes. From pattern recognition I infer initial tornadoes, perhaps 1-3 cyclical supercells. Then it will congeal into quite the bow echo.