Chinook

some brief tornadoes reported in eastern Colorado. Possible large tornado with this supercell complex near CO/KS border

Interesting article by Ian Livingston (a member of this forum,) about NWS Severe Warnings. Discusses: zero-population warnings, millions-population warnings, statistics of warnings vs. population, timeline of warnings throughout 2014-2016. Number of short-fuse warnings per CWA. https://www.washingtonpost.com/news/capital-weather-gang/wp/2016/07/07/what-the-national-weather-service-social-media-warning-stream-has-shown-us/

The 18z NAM/GFS are advertising some extreme supercell parameters in areas of ND/MN tomorrow (ENH Risk for tomorrow.)

There will be 5000-6500 J/kg of CAPE in southern Minnesota tomorrow, along with 30-40 kt of shear and some areas of 200-300 m2/s2 of SRH. If storms develop near this region, there would bring about a pretty high chance of large hail for any cell that develops, and this is also conducive for tornadoes and wind damage.

Note: NWS Billings has surveyed an EF-3 tornado at Baker MT a couple of days ago. Details are available on the NWS Billings web page.

Finally a few severe storms getting going east of Denver. No tornado warnings in northern or central CO that I know of.

Some areas are probably developing thunder, from what used to be rain showers just a short time ago. Still nothing super organized.

For tomorrow: SPC introduced an Enhanced risk for eastern Kansas, western Missouri, and parts of IA and NE. With such high CAPE and some possibility of very low LCLs in Kansas, as well as reasonable SRH and 35kt of shear, this might a signal for >5% tornado risk in some section of eastern Kansas. Eastern Oklahoma may need to have the slight risk also. Edit: also 50-55kt winds at 300mb could help sustain supercells

There are some more severe storms popping in eastern Montana right now, with hail up to 2" reported. And just for the fun of it-- this is an HRRR sounding from just east of Pierre SD this afternoon... 5 digits in the CAPE category.

The Crazy Horse memorial and Mt. Rushmore probably got some lightning nearby - maybe even on the presidents' heads.

This storm has dropped an estimated 5.5" on the Black Hills mountaintops-- this is probably causing raging creeks and rivers, perhaps threatening a few rural areas and campgrounds. I hope there weren't any hikers caught in that. That's some major water and lightning.

possible tornado (or maybe just a huge wind gust) west of New Orleans. base velocity shown here

That's right. There were 79 tornadoes in two days (according to SPC's Severeplot database) and there was more than $1.3 billion damage from hail across the country on April 10.

Name this severe weather event! This is the NARR reanalysis for two consecutive days, at 18z. The maps are from before 2015. What happened on these days?

3-D visualizations of low-swirl, medium-swirl, and high-swirl tornadoes from NCAR https://www2.ucar.edu/atmosnews/perspective/21089/3d-window-tornado

It's kind of funny how much this wind profile is different from the surrounding areas (50 - 200 m2/s2 of SRH, 30-45 kt of shear). Seriously, 500 m2/s2 next to 50 m2/s2. Now that it is so much easier to look at the various parameters from the 4km NAM, we see that deep convection on the model can lead to some very different temp/dew/wind profiles near simulated storms. Given the 25kt-35kt of wind at 500mb tomorrow, (as per the 12z GFS,) I would say tomorrow is most likely to have some multicells with hail/wind. The SPC has an enhanced (ENH) outlook for tomorrow for central Texas, which may make sense. Usually something interesting happens when there is 5000 J/kg of CAPE. For the last few days, I thought maybe tomorrow (Tuesday) would be a bigger severe weather day. With marginal winds at 850mb and 500mb, it should be kind of low on the tornado potential, maybe lower potential on high-end wind and hail.

The 12z and 18z GFS show that the EML (warm layer) will quickly move over the warm, moist sector Monday night, from 00z to 06z, resulting in with some hundreds of J/kg of CINH by 06z.

The 06z day-2 convective outlook, valid for Sunday: the SPC extended the slight risk to northern Oklahoma, as well as northwest IA. Here is a small piece of SPC's discussion: -- EFFECTIVE BULK SHEAR OF 35-45 KT WITH AN ORTHOGONAL ORIENTATION TO THE DRY LINE SUGGESTS DISCRETE SUPERCELLS CAN BE EXPECTED WITH ALL SEVERE HAZARDS.

Sunday could be a regional severe weather threat for areas such as Omaha, Topeka, Kansas City, western Iowa, and Des Moines. 500mb winds will be pretty decent over the warm sector. A dryline will be out ahead of the cold front in central KS, eastern Nebraska.

Isn't Mike Morgan the one who makes all sorts of extreme (and less than helpful) statements on live TV while covering tornadoes???

The 12z GFS has 0.93" liquid equivalent for north Toledo, and 0.59 Akron, 0.42" Canton, 0.56" Cleveland, 0.6", southern Michigan. The 12z NAM has 1.04" liquid equivalent for Toledo, 0.77" Cleveland. If this turns out to be 10-1 or better snow ratios, watch out! By the way, the largest snowstorm my parents had in Toledo this winter is about 3"

The extended range forecast out to 2 weeks in the future looks quite cool for the Midwest. The Day-3 (Easter Sunday) forecast as well as Wed March 30 look like possible severe weather setups. Otherwise the severe weather may be very close to the Gulf of Mexico or there may be none at all for 3-4 days in a row.

It seems like Monday and Tuesday may be slight risk days. Currently the SPC is discussing these days but there are no 15% highlighted areas on the extended outlook maps. The GFS shows medium instability, 1000-2000 J/kg, through parts of the southern Plains, Monday afternoon. As for dynamics, there is a weaker shortwave near Goodland KS, and a strong 500mb jet moving in through northern Mexico into Texas on Tuesday.

Looks like severe season for central Oklahoma just started with a severe thunderstorm watch issued tonight, and a recent wind gust to 58mph.

My dad in Toledo said they just got 4" since the changeover last night, which was their BIGGEST snow day of the SEASON.