December 15th-16th Warmth, Wind, and Severe Threat

[Geoboy645]

I figured that their should be a thread for this storm at this point with the wind threat and unusual warmth. The models are really starting to hone in on a major wind event tomorrow night for most of the region.  Some runs like the 0z GFS even have 70-75mph gusts for multiple locations, especially in Iowa, Northern Illinois and Wisconsin. This could be the largest non-Tstorm wind threat in at least 5 years if not since the Chiclone of 2010 for some areas. I'm increasingly worried about power outages, as our grid is not really used to such sustained heavy winds. Add in the incredibly unusual warmth for this time of year (Madison looks to break their monthly record) and the Iowa severe threat, this is shaping up to be quite the storm for the area despite the lack of wintry weather.

 

[Chicago Storm]

Surprised no one started a thread earlier.


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[Chicago Storm]

Still fully expect a period of 45-60MPH wind gusts across the area tomorrow evening into early Thursday morning.


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[Hoosier]

GFS actually has some areas of gusts in excess of 80 mph.  

[Hoosier]

About the only "negative" factor I can come up with is that it's mid-December and not a couple months earlier.  Trees without leaves can handle more wind than trees with leaves.  That being said, it's not going to prevent this from having a pretty high impact.  Expect a ton of power outages and tree damage in the sub.

[hlcater]

Wind driven moderate with a 10% tor. Did not expect that.

[Hoosier]

Absolute insanity to get a moderate risk that far north in the middle of December.  Wow.

[cyclone77]

30 minutes ago, Hoosier said:

GFS actually has some areas of gusts in excess of 80 mph.  

That is insane.  We've had many 60+mph gradient wind events over the years.  The event in November 98 was probably the most impressive one that I've experienced, and there were gusts pushing 70mph with that.  If we can get above 70mph with this that's extremely impressive.  The GFS is downright scary to be sure.  

High-res models continue to be less ominous, with the highest winds generally staying well northwest of the DVN/LOT cwas other than the brief window with the precip/fropa.  

[Hoosier]

My jaw is still on the floor from that SPC outlook.  With highly anomalous setups can come highly anomalous outcomes though.

[fluoronium]

Any amount of severe weather in that region would be historic for the time of year, so this has the potential to be absolutely insane. It's too bad storms are going to be mainly at night and moving at incredibly fast speeds.

[sbnwx85]

What a lovely Maycember we are having.

[cyclone77]

New Euro less ominous than previous runs for the DVN area.  50-55mph wind gusts for most of the cwa, with the highest gusts to near 60 out in the northwest cwa.  Perhaps a shift more towards what the high-res models have been advertising all along, a further northwest position of higher winds.  The enthusiast part of me wants the GFS 70mph+ winds to verify, but the homeowner part of me is kind of hoping the high-res/new Euro model solutions pan out lol.

[Hoosier]

Not comparing the two setups, and obviously we don't know how this one will play out yet (maybe it will underperform), but to the point of getting unusual outcomes, I think back on the 10/26/2010 system and what that did.  The severe wx initiated in the wee hours of the 26th.  I think the first tornado happened like 4 am, and then it just started ripping tornadoes all morning.  Vast majority of the tornadoes were weak but it's basically unheard of to get a tornado outbreak initiating/occurring at that time of day in this part of the country.  Strange and rare things can happen when the ingredients are there, regardless of the time of day or time of year.  Will be interesting to watch.  

[OrdIowPitMsp]

There has a never been a recorded tornado in Minnesota in December. 
 

Let’s see how today changes that.

[Powerball]

6 hours ago, hlcater said:

Wind driven moderate with a 10% tor. Did not expect that.

I called it back on Sunday. A lot of similarities to the severe weather setup tonight with this past Saturday/Sunday.

At least this time around, the heightened threat level is being a lot more hyped earlier. Perhaps this will convince more people to be more dilligent about monitoring the weather conditions this evening.

[WeatherMonger]

Expanded the moderate and added hatching to the 10% area

 

 

[purduewx80]

Hatched tor probs look good. Think supercells are a bit more likely in NW/NC IA into SC/SE MN just S/SW of Minneapolis - this is where deep layer shear is a little more perpendicular to the dryline/pre-frontal trough. MOD is definitely warranted for the wind. Derecho followed by strong synoptic winds and then cold weather is going to be ugly. 

 

[Chicago Storm]

Hatched tor probs look good. Think supercells are a bit more likely in NW/NC IA into SC/SE MN just S/SW of Minneapolis - this is where deep layer shear is a little more perpendicular to the dryline/pre-frontal trough. MOD is definitely warranted for the wind. Derecho followed by strong synoptic winds and then cold weather is going to be ugly. 
 

Agree, 10% hatched tor and 45% hatched wind look good. I’d expect wind probabilities to be expanded a bit for the next update.


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[tim123]

Crazy day ahead no matter what time of year. I suspect there will be 100 mph gust in that line that form. With crazy fast moving tornadoes.

[purduewx80]

50 minutes ago, Chicago Storm said:

Agree, 10% hatched tor and 45% hatched wind look good. I’d expect wind probabilities to be expanded a bit for the next update.

Very curious to see how the SPC and WFOs handle that tonight. LOT already forecasting severe wind gusts with the showers. About as much lead time as you'll ever see in a TAF.

[purduewx80]

17 hours ago, hlcater said:

This setup has almost everything going for it except MLCAPE. 

CAMs playing catch up.

[olafminesaw]

Thank goodness the main threat area misses the Cedar rapids area. 

[CheeselandSkies]

Been a while since I saw a setup where the 3KM NAM sim ref/UH product was more bullish than the HRRR with implied supercell/tornado potential. 12Z HRRR has a solid, narrow line of convection tied to the front with little UH >75. 12Z 3KM NAM for western IA at 12 hrs OTOH...

[Chicago Storm]

Very curious to see how the SPC and WFOs handle that tonight. LOT already forecasting severe wind gusts with the showers. About as much lead time as you'll ever see in a TAF.

My guess is would be they would be forced to issue severe t’storm warnings. If a wind advisory were in place, you might be able to go with a short fused high wind warning…But with one already in effect, it leaves little in the way of other options.


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[Chicago Storm]

Thank goodness the main threat area misses the Cedar rapids area. 

I wouldn’t get ahead of yourself, yet.


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[tim123]

Severe thunderstorm warning in Colorado now. 80 mph winds.

[tim123]

Anyone know what these streaks on 3km nam are? Never seen them.

[Powerball]

1 minute ago, tim123 said:

Anyone know what these streaks on 3km nam are? Never seen them.

It's where the models are picking up strong rotation as the cells move through.

[hardypalmguy]

9 hours ago, Geoboy645 said:

I figured that their should be a thread for this storm at this point with the wind threat and unusual warmth. The models are really starting to hone in on a major wind event tomorrow night for most of the region.  Some runs like the 0z GFS even have 70-75mph gusts for multiple locations, especially in Iowa, Northern Illinois and Wisconsin. This could be the largest non-Tstorm wind threat in at least 5 years if not since the Chiclone of 2010 for some areas. I'm increasingly worried about power outages, as our grid is not really used to such sustained heavy winds. Add in the incredibly unusual warmth for this time of year (Madison looks to break their monthly record) and the Iowa severe threat, this is shaping up to be quite the storm for the area despite the lack of wintry weather.

 

Looks beautiful.  Warm weather and hurricane winds.  All we need is some palm trees to take some awesome video.

[tim123]

This severe threat may start much sooner than forecasted. Even meso models playing catchup.