Tim from Springfield (IL)

Huge change this afternoon to tomorrow's Day 2 slight, now it covers basically STL eastward to the Mid-Atlantic, including roughly I-72 southward in Illinois:

https://www.spc.noaa.gov/products/outlook/day2otlk.html

...The Ohio Valley Region and vicinity...
   Morning convection -- and possibly some accompanying severe
   potential -- should be ongoing over the Ohio vicinity, and will
   shift southeastward across the central Appalachians through the
   morning in tandem with a mid-level vort max.  Subsidence aloft in
   the wake of this feature -- within background ridging -- should
   maintain a capping inversion, which should hinder new convective
   development through the day ahead of a weak/advancing front/wind
   shift, associated with the next in a series of mid-level vorticity
   maxima progressing through west-northwesterly flow aloft.

   At this time, degree and timing of new storm development over the
   Ohio Valley remains quite uncertain, but current thinking is that
   scattered to isolated storms should develop along the weak boundary,
   from lower Michigan southwestward to Missouri, with the first storms
   possibly initiating by around sunset.  Convection would then spread
   east-southeastward with time across the Ohio Valley states,
   gradually increasing in coverage with time.

   Given steep lapse rates aloft, instability will support vigorous
   updrafts -- aided by the moderately strong west-northwesterlies
   through a deep layer.  Along with potential for large hail, damaging
   winds will also be possible -- particularly if storms can grow
   upscale locally into line segments/clusters.  The storms should
   continue through the overnight hours in an east-northeast to
   west-southwest band, crossing the central Appalachians and possibly
   moving into the Tennessee Valley through the end of the period.

Not sure if the next three days warrant a separate severe thread but this was prompted by huge changes this afternoon to tomorrow's Day 2 outlook.

The narrow marginal risk for today from the LOT CWA to NW OH remains intact at this time.  Also a marginal in C/W Minnesota too:

https://www.spc.noaa.gov/products/outlook/day1otlk.html

 

...Great Lakes including portions of IL/IN/OH and Lower MI...
   Scattered thunderstorms are still expected to develop this evening,
   initially across northern Illinois and the southern Lake Michigan
   vicinity, and subsequently expand and develop eastward across other
   parts of the region through the overnight. This activity will be
   focused along/just north of a northward-advancing warm front as
   low-level warm/moist advection increases.

   In an environment characterized by steep mid-level lapse rates and 
   MUCAPE of 500-1000 J/kg in the presence of 30-45 kt effective-shear,
   the more robust elevated updrafts may produce occasionally severe
   hail. A seemingly less certain risk of locally damaging winds cannot
   be ruled out, particularly if storm mergers/organization occurs in
   immediate proximity of the surface warm front.

   ...Eastern Dakotas/western Minnesota...
   Isolated thunderstorms are expected to develop by evening across
   parts of the region, influenced by weak height falls and increasing
   warm advection related to an amplifying trough over the Canadian
   prairies. While the overall environment will not be particularly
   moist, given steep mid-level lapse rates and ample shear through the
   cloud-bearing layer, it is conceivable that a couple of the stronger
   storms could produce hail to near severe levels tonight.

2 hours ago, StormChaser4Life said:

It's seriously embarrassing what ILX does. They always refer to SPC discussion. Like do your own analysis. DVN was uncharacteristically conservative. LOT great as always. Not sure what the other offices aren't seeing

IMO, even the wording of both the local area forecast for Sangamon County and their point-and-click for my location (Chatham, IL) both make it appear that ILX doesn't seem impressed about this storm threat, at least for this area.  

Their current Sangamon County forecast for tomorrow: "Warmer. Rain showers and thunderstorms."  No mention of severe yet.  Point and click only shows the generic "showers and thunderstorms" with no severe mention either.  That doesn't sound like "enhanced/moderate risk for severe" to me. 

It was worse earlier today: "Rain showers and some thunderstorms."  That especially doesn't scream "severe" to me; more like a "few showers with a rumble of thunder or two."

Either ILX's forecasting is a joke, or they're seeing something for this area that we and the other models/NWS offices are not.

I'm sure tomorrow's morning ILX HWO will have the "conference call for emergency managers" statement at the end of the outlook, for sometime late in the morning for areas in at least the Enhanced risk.  Maybe even some of the Slight areas too.

Also, how much stock does anyone on here take in local TV weathercast "Futurecast radars."  None of the ones I've seen on the three major newscasts in the Springfield/Decatur/Champaign market at 6PM seemed to put much activity (other than a few isolated cells) in the current MDT/hatched TOR area.  It looked as if they wanted to get more isolated storms going roughly along and east of a STL-LaSalle line, with some intensifying and expanding in size.  Not impressed with what I saw on local news tonight, even though they were emphasizing SPC's moderate risk prediction.

The Northern IL Severe Weather blog's take on Saturday, including an interesting map:

https://nilsevereweather.weebly.com/blogs-weather-updates/severe-weather-threat-increasing-across-illinois-on-saturday-all-hazards-possible-nisw?fbclid=IwAR3Fl2HpqFhOeBgOlPMxSpq_jdqNQJaRwm5oWerPGRYns_cBgLWV7S-s_ag

The blogger also linked to the following SPC map image, including a radar image of long-tracked cells tracking straight northeast west and north of Peoria.  With a serious-looking long-tracked cell shown from west of Canton to LaSalle-Peru.  Plus some nasty cells over and just northeast of PIA:

I went ahead and started a new thread for the late-week threats here in the sub, especially what may be the main event Saturday:

Going to start a separate thread for the current end-of-week severe threats, especially what may be the big show in IL on Saturday (after the rare Day 3 afternoon update):

https://www.spc.noaa.gov/products/outlook/day3otlk.html

Also, the 2:49 CDT Day 1 now has a slight entering the STL Metro East area in IL, with a narrow hatched hail area from E KS to E MO:

https://www.spc.noaa.gov/products/outlook/day1otlk.html

Most of the sub is in Marginal for Day 2 at this time:

https://www.spc.noaa.gov/products/outlook/day2otlk.html

ILX with the evening forecasts just extended the WWA to the I-55 corridor, including Springfield, Lincoln, and Bloomington.

Snow/sleet/freezing rain mix in Chatham (10 miles southwest of State Capitol) now.  Glaze of snow and sleet on ground now.  Reports of roads starting to get slick, and Google Maps traffic map showing slow go on I-55 and I-72 here in Sangamon County.

MIxed precip + Saturday night + lackadaisical snow/ice removal in Springfield area in recent years = Travel unadvisable in SPI tonight

I don't usually like to start a severe thread, and don't mean to be late to the party on today's event either, but I started a new catch-all thread starting with today/tonight's action (including another MD in IA/N IL), going to early Wednesday: