Hoosier

20z outlook expresses some doubts about convective coverage in the ENH area.

Area Forecast Discussion National Weather Service Chicago/Romeoville, IL 203 PM CDT Sat Jun 1 2019 SHORT TERM... 155 PM CDT Through Tonight... An outflow/lake breeze composite boundary has pushed inland to near a Woodstock to Naperville to Wheeler line based on latest surface observations. The airmass to the east and north of this boundary has been stabilized, with dewpoints in the upper 50s and temperatures in the upper 60s. This stabilization is also demarcated by stable wave clouds on GOES-16 visible satellite imagery. Latest guidance does indicate the breezier synoptic southwesterly flow may force this boundary back east a bit through the afternoon hours, and how this modified airmass impacts the severe potential into portions of Lake (IL) and Cook counties remains a bit uncertain at this time. Recent ACARS soundings out of Midway show this stable layer is pretty robust, with a notable temperature inversion present near the surface. With additional diabatic heating, would expect at least some airmass recovery on the cool side of this boundary with baroclinicity starting to wash out a bit over the next 1 to 3 hours. If this boundary remains robust, however, it could locally mute the severe threat into Cook and Lake counties later this evening by limiting the potential for strong downdrafts and associated winds to reach the surface. The other question stems around a notable pocket of dry air now being analyzed in the 850-700 mb layer with 850 mb dewpoints under 0 C now being analyzed across portions of northwestern Illinois and into our far western counties. This could tend to work against updraft intensity--at least initially--although an axis of much higher moisture is analyzed near I-90. With surface temperatures having warmed into the 80s, dewpoints in the lower 60s, and steep mid-level lapse rates in place overhead, MLCAPE values are, nonetheless, inching past 2000 J/kg early this afternoon, especially near and west of the I-90 corridor. Mid-level winds are also increasing ahead of a small but sharp shortwave, and effective deep layer shear values are pushing north of 30-35 kts across the region (lower south of I-80, highest north). 500 mb height falls on the order of 50-60 m/12 hr have been noted spreading towards southern Wisconsin. Associated increases in forcing for ascent will be responsible for expanding showers and thunderstorms along and incoming cold front through the evening hours. All of this taken together spells a continued threat for strong to severe storms across our region this afternoon. Hi-res guidance continues to struggle with a rather wide disparity in solutions still noted this afternoon. Storms are beginning to develop across southwestern Wisconsin at this hour, near a developing weak surface low and at the leading edge of stronger ascent from the incoming shortwave. Latest thinking is that storms will continue to develop south and westward over the next hour or two, eventually nearing Winnebago, Ogle, and Lee counties towards 4 PM or so. Additional convection is also attempting to develop along the aforementioned outflow/lake breeze across southern Cook and into Lake (IN) and Porter counties. The airmass immediately ahead of this boundary is unstable and only weakly capped, so we will need to keep an eye on this area for potential storm development as well. Initial discrete/isolated activity will carry a risk for large hail (potentially up to ping pong-golf ball sized), but storms should quickly begin to congeal into line segments as robust forcing overspreads the area. As a result, the severe threat will begin to transition to mainly wind damage, with a potential for 60-70 mph wind gusts. At this time, think the main severe corridor may end up developing near and north of I-80, and particularly focusing along I-88 and I-90 where instability will be maximized. The tornado threat is low from a synoptic standpoint with minimal low-level hodograph curvature, but we will be keeping an eye on any stronger updrafts which manage to develop near this feature later this afternoon. A brief tornado spin-up or two can`t be ruled out in the vicinity of this boundary, but the main severe risk still appears to be from hail and damaging winds. Looks like a surging line of storms will move out of our south and eastern counties by mid-evening with a continued threat for strong to locally damaging wind gusts. Will be holding onto some low PoPs behind this line of storms with lingering moisture and some instability to work with, but the main severe window will come to a close by about 9-10 pm area-wide. Carlaw

I'm wondering that too. Not sure if the models get continuous input on the state of the vegetation.

The boundary that just went through Chicago *could* locally enhance the tornado threat a little for anything tracking along it later... wherever it is by then.

Another smoky sky day. Was reading about the Canada fires. Can't believe how bad they already are on June 1.

Yeah, the threat in northern IL looks as decent if not better than where the ENH is currently placed.

Dews coming in under guidance would temper instability some, as has been mentioned in the discussions. Haven't checked to see how the CAMs are handling dews.

LOT added a couple more EF0 tornadoes from May 27.

Upgraded to enhanced farther south/west Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1234 PM CDT Fri May 31 2019 Valid 011200Z - 021200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM KANSAS INTO A PORTION OF THE MIDWEST... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER A PORTION OF THE SOUTHERN PLAINS... ...SUMMARY... Scattered severe storms are possible Saturday afternoon central and eastern Kansas, northern Oklahoma, Missouri, Illinois and extreme southeast Iowa. Other more isolated strong to severe storms are possible from the southern through central High Plains. Large hail and damaging wind will be the primary threats. ...Synopsis... Shortwave trough now over the northern High Plains will become absorbed within the amplifying northern stream and move southeast through the Midwest region Saturday. Cold front initially from the upper Great Lakes through western KS will move southeast, and by early evening should extend from the southern Great Lakes, northern MO into southeast CO where it will likely stall. ...Central Plains through the Midwest regions... The atmosphere from KS through the Midwest is expected to become moderately to strongly unstable Saturday afternoon with 2000-3000 J/kg MLCAPE supported by the northeast advection of low-mid 60s F dewpoints through the warm sector beneath plume of steeper (7-7.5 C/km 700-500 mb) lapse rates. Some model solutions are overdone with low-level dewpoints by several degrees, apparently due to excessive evapotranspiration, but correcting for this still supports moderate to strong instability as the surface layer warms during the afternoon. Widely scattered to scattered storms are expected to initiate along the cold front by mid afternoon as the boundary layer destabilizes and the cap weakens. Northwesterly winds will strengthen to 40+ kt at 500 mb, especially from eastern KS through central IL as height gradient increases in association with the amplifying upper trough. This will support 35-40 kt effective bulk shear. Both supercell and multicell storm modes are expected with initial discrete storms eventually consolidating into lines or clusters as they spread southeast. Damaging wind and large hail will be the main threats. ...Southern High Plains... Storms are expected to once again develop over the higher terrain of NM and southwest TX and subsequently spread east into the High Plains. Have introduced a slight risk over this region where a belt of somewhat stronger winds aloft and moderate instability will promote a parameter space sufficient for a few supercells capable of large hail and damaging wind. ...MAXIMUM RISK BY HAZARD... Tornado: 2% - Marginal Wind: 30% - Enhanced Hail: 30% - Enhanced ..Dial.. 05/31/2019

Meteorological summer is upon us.

What's the deal with this haze/smoke?

It does look slight risk worthy.

First EF4 in Ohio since June 5, 2010.

Correct. June is most active with a long term average of about 5 per June, though obviously this can vary tremendously in any given year. June 2018 only had 2. The first half of June is a bit more favored than the second half. April is the second most active month, with May slightly behind April.

We are up to about 40 tornadoes in the subforum for May 27-28, with about 11 EF2+ (I'm not being too precise with the numbers right now since they could increase). Fwiw, the June 5-6, 2010 outbreak produced about 45 tornadoes in the sub.

Definitely had a rather tame outcome in N IL. LOT has confirmed only 3 weak ones so far. Public Information Statement National Weather Service Chicago IL 222 AM CDT Wed May 29 2019 /322 AM EDT Wed May 29 2019/ ...NWS DAMAGE SURVEY FOR 5/27/2019 TORNADO EVENT... .OVERVIEW...The NWS Chicago office, with the help of Emergency Management, law enforcement, trained storm spotters, and academic partners has determined three EF-0 tornadoes occurred on Monday (Memorial Day). Thank you to those partners for their assistance. Other wind damage reports are still being assessed from northern Will and southern Cook Counties in northern Illinois, as well as in Benton County in northwest Indiana. .Plattville Area Tornado in Southern Kendall County... Rating: EF-0 Estimated peak wind: 65 mph Path length /Statute/: 1 mile Path width /Maximum/: 30 yards Fatalities: 0 Injuries: 0 Start date: 5/27/2019 Start time: 1:47 PM CDT Start location: 2.5 NNW of Plattville IL Start Lat/Lon: 41.5732 / -88.4136 End date: 5/27/2019 End time: 1:48 PM CDT End location: 2.5 N of Plattville IL End_lat/lon: 41.5730 / -88.3948 A tornado briefly touched down near the intersection of Walker Road and Ashley Road. Video and photo show that the tornado kicked up dust in an open field with no damage reported. .Paw Paw Area Tornado in Eastern Lee County... Rating: EF-0 Estimated peak wind: 65 mph Path length /Statute/: 0.7 miles Path width /Maximum/: 30 yards Fatalities: 0 Injuries: 0 Start date: 5/27/2019 Start time: 4:27 PM CDT Start location: 4 SW of Paw Paw Start Lat/Lon: 41.6579 / -89.0466 End date: 5/27/2019 End time: 4:28 PM CDT End location: 4 SW of Paw Paw End_lat/lon: 41.6579 / -89.0332 A brief tornado occurred based on trained spotter reports. This was just east of Interstate 39. Damage was not reported with this touchdown. .Dyer Tornado in Lake County Indiana... Rating: EF-0 Estimated peak wind: 85 mph Path length /Statute/: 1.1 miles Path width /Maximum/: 100 yards Fatalities: 0 Injuries: 0 Start date: 5/27/2019 Start time: 4:30 PM CDT Start location: 1 SSW of Dyer IN Start Lat/Lon: 41.4924 / -87.5256 End date: 5/27/2019 End time: 4:33 PM CDT End location: 1.2 SE of Dyer IN End_lat/lon: 41.4822 / -87.5053 The tornado touched down in a subdivision causing damage to trim, shingles, siding, and fascia on several homes, as well as to a chimney on one home. Multiple trees were snapped and many lost limbs. The tornado also flipped a backyard shed and damaged fencing. The homes between Willow and Scotty Lanes appeared to sustain the worst damage.

There's definitely a positive correlation between tornado width and intensity. You just have to be careful to avoid absolutes. A wide tornado does not guarantee an intense one, just as a narrow tornado does not necessarily indicate a weak one.

Surface front is pretty far south in central IL. Main threat for IKK area would be some hail. Probably going to be tough to realize much of a wind threat that far north, though can't completely rule out some gusts getting through the stable layer especially with any well organized convection.

That thing looked like a beast.

So this is cool. You can plot the SPC outlooks over a period of time by WFO/State/County. It gives the highest risk level for each day. https://mesonet.agron.iastate.edu/plotting/auto/?q=201 A lot of neat features besides the outlooks to play with in the dropdown box, too.

Trends would suggest heaviest rains tonight generally south of I-80. We'll see.

I find this stuff to be fascinating.

Congrats on the catch. Looks like they have it as EF0. Will be curious to see what the path length was because I observed damage west and east of Hart St, though I guess some of it could've been straight line wind. Could've been much worse locally. We both know how developed the area is where that cell tracked.

Survey info from IND https://www.weather.gov/ind/may28stormsurvey