Hoosier

VYS gusted to 63 mph a little while ago. BULLETIN - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Warning National Weather Service Chicago/Romeoville 103 AM CST Wed Nov 27 2019 The National Weather Service in Chicago has issued a * Severe Thunderstorm Warning for... Kendall County in northeastern Illinois... Northeastern La Salle County in north central Illinois... Southern De Kalb County in north central Illinois... Northern Grundy County in northeastern Illinois... * Until 145 AM CST. * At 102 AM CST, severe thunderstorms were located along a line extending from near Earlville to near Naplate, moving northeast at 55 mph. HAZARD...60 mph wind gusts. SOURCE...Radar indicated. IMPACT...Expect damage to roofs, siding, and trees. * Locations impacted include... Oswego, Ottawa, Yorkville, Little Rock, Minooka, Plano, Sandwich, Marseilles, Serena, Montgomery, Sheridan, Somonauk, Earlville, Newark, Leland, Naplate, Millington, Lisbon and Boulder Hill. Including the following interstate... I-80 between mile markers 84 and 105, and between mile markers 115 and 122. This includes...Buffalo Rock State Park, and Grundy County Speedway and Fairgrounds. PRECAUTIONARY/PREPAREDNESS ACTIONS... For your protection move to an interior room on the lowest floor of a building. && LAT...LON 4161 8906 4163 8899 4163 8894 4164 8894 4173 8860 4172 8860 4172 8826 4144 8825 4129 8894 TIME...MOT...LOC 0702Z 235DEG 48KT 4157 8897 4128 8886 HAIL...<.75IN WIND...60MPH $$ Kluber

Temp has jumped into the mid 50s.

Warm holidays are the worst. Thankfully the Euro weeklies are pretty hit or miss that far out.

Tornado warning in Southeast Missouri.

NAM trying for some front end wintry stuff farther south of where other models have been advertising. It is the NAM so it could be out to lunch... however, the surface high is decently positioned initially so maybe could have just enough low level cold air hanging around. Something to watch anyway for those who are mostly sitting on the sidelines winter wx wise.

Models have a band of 50-55 kt winds at 925 mb swinging through tomorrow, so even if mixing to 850 mb doesn't occur, it shouldn't be that tough to get gusts near warning criteria. I do think there could be some gusts nudging over 60 mph in LOT... maybe not frequent gusts over 60 mph at any given location but at least isolated/scattered. Area near/south of I-80 may be slightly favored for that.

See my above post. Wow. Lol

Just waiting for the first "see, I knew getting that early snow was a bad sign for winter."

Looking back, this should be the best large scale wind event in the LOT cwa since at least February of this year. Neighboring offices have upgraded to a high wind warning and would expect LOT to follow suit.

Enhanced risk area, but the discussion didn't sound too confident about it.

HRRR gust map is pretty entertaining tomorrow.

00z Euro looks sort of peculiar in its handling of the surface low. It has it deepening to 980 mb at 18z Wednesday and then fills to 994 mb just 6 hours later. That kind of deepening will probably have some ramifications with the wind output but will see in a minute.

Marginal and slight risk areas expanded on the new outlook Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1156 PM CST Mon Nov 25 2019 Valid 261200Z - 271200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE LOWER/MID MS VALLEY... ...SUMMARY... Isolated to scattered severe storms with a threat for damaging winds and a few tornadoes will be possible across parts of the lower to mid Mississippi Valley this afternoon and tonight. ...Synopsis... A powerful mid-latitude cyclone will strengthen further today as it acquires a negative tilt and ejects northeastward from the southern/central Rockies across the Plains, eventually reaching the Upper Midwest and Great Lakes region by the end of the period. A very strong mid/upper-level jet (100+ kt at 500 mb and 175+ kt at 250 mb) will likewise develop from the southern/central Plains across the mid MS Valley by Tuesday night. Pronounced large-scale forcing for ascent preceding the mid/upper-level trough will encourage a surface low to deepen as it develops northeastward from the central High Plains to the Upper Midwest by late tonight. A cold front attendant to this low will sweep quickly eastward across the southern Plains through the day. This front should reach parts of the OH/TN Valleys into the Southeast by early Wednesday morning. ...Lower to Mid Mississippi Valley... South-southwesterly low-level winds will continue to transport Gulf moisture northward this morning across parts of central/east TX and the lower MS Valley. Latest short-term guidance is in reasonable agreement that low to mid 50s surface dewpoints should extend as far north as northern MO and southern/central IL by this evening. Greater low-level moisture characterized by mid 60s to near 70 F surface dewpoints will likely remain confined farther south to parts of AR/LA/MS and east TX. At least two corridors of isolated to scattered severe thunderstorms may occur today/tonight: one in close proximity to the mid-latitude cyclone from MO northeastward into eastern IA and IL, and the other from AR to the Mid-South, possibly extending as far south as southern/central MS. Convection should develop along/ahead of the front across MO by late afternoon/early evening as strong ascent overspreads this region. Even though low-level moisture should be somewhat more limited with northward extent, temperatures should rapidly cool at mid-levels as the upper trough approaches. MLCAPE of 250-750 J/kg should develop by the time convective initiation occurs, with some guidance suggesting MLCAPE may reach near 1000 J/kg. Very strong shear owing to rapidly increasing wind speeds through the cloud-bearing layer suggest supercells will be possible initially, with both a damaging wind and isolated tornado threat. Isolated large hail may also occur early in the convective life cycle given the modestly steepened lapse rates and very cold temperatures aloft. A small bowing cluster should develop by late evening and quickly race northeastward into parts of IL, with mainly a damaging wind risk possibly continuing into early Wednesday morning as far east as western IN. A somewhat separate area of convection may form across the open warm sector in AR and the lower MS Valley by late afternoon owing primarily to low-level warm air advection and weak confluence along a pre-frontal trough. Very strong effective shear (60+ kt) and 500-1000 J/kg of MLCAPE will support supercell structures with any storms that can form in this regime. Isolated instances of damaging winds and a couple tornadoes should be the main threats with this convection. There is some uncertainty with overall coverage through early evening, particularly with southward extent across LA and southern/central MS, as these areas will remain displaced to the south of the stronger large-scale ascent. Still, some increase in thunderstorm coverage with an isolated severe threat may occur late in the period (early Wednesday morning) as the surface cold front approaches and a 35-50+ kt southwesterly low-level jet remains over this region. ..Gleason/Nauslar.. 11/26/2019

Check out the afd out of Medford, OR in regards to the big storm set to come onshore. Really something. October 1962 is pretty much the benchmark storm for the west coast. This is not that but it's impressive enough. Area Forecast Discussion National Weather Service Medford OR 332 PM PST Mon Nov 25 2019 .SHORT TERM...Today will be the calm before the storm. A rapidly rapidly deepening "bomb" cyclone will take aim for the Southern Oregon Coast on Tuesday. The main message today is to prepare today ahead of this storm and if you have travel plans, now would be the time to do it. Weather conditions will deteriorate rapidly on Tuesday with strong winds and heavy snow impacts expected over much of the area. This low is unprecedented in its strength and track. It`s also historic because storms of this magnitude have not been observed on this track in the last 40 years or more! Keep in mind, the location of the highest winds will largely depend on the exact track of the low. Small shifts in the track will make a difference in which areas see very strong winds. So have a way to stay up to date on the forecast and watch for updates. Overall, the majority of the models and ensembles bring a 974 mb low into the Curry Coast on Tuesday, then move the low onshore near the California-Oregon border Tuesday evening and inland over the area Tuesday night into Wednesday morning. Ahead of the low center, expect very strong winds at the coast and over some inland western areas along with heavy snow for the mountain passes (including Sexton Summit, Siskiyou Summit, pass over the Southern Oregon Cascades, and areas near Mount Shasta). As the low moves inland, expect wrap around showers to affect the area Tuesday night into Wednesday. Snow levels will lower to some western valley floors during this time bringing the potential for valley snow impacts. High winds and moderate to heavy snow will be the main impacts from this storm. Please see details below. -Petrucelli WIND...Low pressure out around 48N and 146W will rapidly intensify tonight into Tuesday. The pressure of this developing storm this evening at 4 pm PST will be around 1020 mb. The storm will "bomb" out, with the pressure lowering to below 980 mb by 4 pm PST on Tuesday. It will move to a position near 42N and 125W, just off the SW coast of Oregon (or about 50-100 miles west of Gold Beach). This is a greater than 40 mb drop in just 24 hours. A "bomb cyclone" is defined as a 24 mb drop in 24 hours, so this one is almost double that and wind impacts will be felt across the entire area. What makes this storm unique is the trajectory that it will take as it deepens and moves inland. Rather than a deepening system moving from SW to NE inside 130W, which typically bring our strongest coastal and inland wind storms in SW Oregon and northern California (and onshore gradients ALL along the coast), this one will be moving in from NW to SE as it moves onshore Tuesday evening. This will focus the core of the strongest winds (and onshore gradient) for the headlands/beaches from Cape Blanco southward. Winds in those places will likely gust in excess of 75 mph with gusts in excess of 100 mph possible at exposed areas and headlands. This is a dangerous storm and we don`t want to downplay the winds for areas farther north, but an easterly (offshore) gradient usually results in the winds getting blocked somewhat by the terrain. We are still expecting gusts of 45 to 55 mph at North Bend, but that`s the reason it should be somewhat lower there.

Pulling forecast soundings from the IL/IN area and man, the speed shear is just phenomenal. About as good as it gets. 0-6 km shear progged in the 100-110 kt range (may be a struggle to even get convective tops much past 6 km though).

Check out the wind fields in central IL at the end of the 21z RAP. Yikes, lol. Not really in its more useful range yet though. And good point about clouds potentially cutting into the top end potential.

Totally expect to receive leaves from Illinois on Wednesday. Seems like most factors sort of maximize either side of I-80, so that corridor and maybe about 75-100 miles north and south should get some of the highest gusts. I'm a fan of the diurnal timing too.

The coordination is evident this afternoon as a bunch of offices have rolled out a high wind watch.

Something I have noticed on the models is that the surface based instability (what amount there is) tends to lag behind the potential convective line on Tuesday night into early Wednesday. There isn't really as much of a lag when using MLCAPE. So what it means is that if temps can warm up a bit quicker out ahead of the front (which is a distinct possibility with the strong southerly/southeasterly low level flow) then some surface based instability could develop more quickly for any convection to try to take advantage of.

The gust maps tend to overdo things in poor mixing regimes, but mixing depths behind the front should be respectable so this could be a reasonable representation. 12z Euro valid at 18z Wed

NAM ticked up a bit with instability. May have a shot at some surface or near surface based activity farther north/east in IL/IN despite the overnight timing. I'll say it again... boy if we had better instability with this setup. Would've been a big severe wx outbreak.

Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1140 AM CST Mon Nov 25 2019 Valid 261200Z - 271200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER A PORTION OF THE LOWER TO MIDDLE MISSISSIPPI VALLEY... ...SUMMARY... Isolated severe storms with a threat for mainly damaging wind and a couple of tornadoes will be possible over a portion of the lower to middle Mississippi Valley region Tuesday. ...Lower to middle Mississippi Valley region... A strong shortwave trough now approaching the Great Basin will emerge over the central and southern Plains early Tuesday. A mid-upper jet within base of this feature will strengthen to 120 kt as the shortwave trough ejects negatively tilted through the middle MS Valley region. Lee cyclone initially over the southern High Plains will deepen within exit region of the upper jet as it develops northeast through the middle MS Valley by Tuesday evening. Trailing cold front will advance east and southeast through the central and southern Plains and MS Valley. By the end of the period the front should extend from a surface low over upper Great lakes southwest through LA and the TX coastal area. The boundary layer over the northwestern Gulf is in the process of modifying with latest observations showing dewpoints already in the upper 60s F. Positive theta-e advection promoted by southerly low-level winds will persist through Tuesday contributing to surface dewpoints near 70 F as far north as southern AR with upper 50s F into central MO. Widespread clouds should limit diabatic heating in warm sector, but MLCAPE should approach 1000 J/kg over the lower MS Valley. Farther north from eastern KS into MO the development of steeper lapse rates with colder air aloft (-14 to -16 C at 500 mb) will contribute to marginal MLCAPE with 500-800 J/kg possible within a more shallow convective layer. Two primary zones of surface based thunderstorm development are possible Tuesday afternoon and evening, including along the warm conveyor belt from northern LA into AR, western MS and TN, and farther north within zone of stronger pre-frontal forcing ahead of the cold front from eastern KS into MO and western IL. Broken bands of storms including potential for a few supercells and bowing segments will be possible in both of these regimes where vertical shear profiles will be more than adequate for organized structures with sizeable 0-1 km hodographs and 50+ kt effective bulk shear. Primary limiting factor for higher severe probabilities is the expected marginal thermodynamic environment. Nevertheless, at least isolated damaging wind and a couple tornadoes will be possible with the stronger storms. ...MAXIMUM RISK BY HAZARD... Tornado: 5% - Slight Wind: 15% - Slight Hail: 5% - Marginal ..Dial.. 11/25/2019

If you're in northern IL you look at this and think hey, maybe a decent snow on the way. Nope

Takeoffs and landings might be a bit bumpy on Wednesday. This is @ORD on Wed afternoon. Nearly dry adiabatic into 65 kt flow at 850 mb. Likely would be high wind warning criteria if this verified exactly as is but we'll see how it evolves in the next couple days.