CheeselandSkies

Yes, even without the obvious weirdness in the wind profile, that is why I always question a "PDS TOR" sounding when it has no quality "sig" analog matches.

Despite lack of impressive composite values (EHI/STP etc.), synoptic pattern Wednesday evening over Iowa shown on 3KM NAM is suggestive (surface low with backed winds ahead of it, low 60s dewpoints nosing up to the warm front). Will continue to monitor, although would have dearly loved to see more model agreement by this point.

GFS meanwhile seems to be sticking to its guns in depicting a much more robust severe threat over parts of Iowa Wednesday afternoon/evening...this one is gonna be down to the wire with both models basically locked in on their solutions for multiple runs. What a forecasting nightmare. About the only favorable factor I can find consistently across both models is very steep lapse rates in the warm sector, which most previous systems this year have been lacking. However as the NAM suggests that may be the result of an unbreakable cap.

12Z NAM remains unimpressive.

Yeah, I read the outlook. The wording sounds like they expect mainly hailers. I had higher hopes for this setup when people were talking about how ominous it looked in the Day 8 or so range. I'll need to see the NAM come around some before I start feeling good again about my decision to take Wednesday off to chase.

Big downtrend for Iowa with the 15% barely nudging into the SE corner of the state after most of the state being in the Day 4 30%. Looks like SPC is leaning more towards the NAM, which remains worlds apart from the GFS which has actually increased the EHI over the area on recent runs. Not impressed with this system as it gets closer, at this point not looking like a significant tornado event for anyone.

Doubtful but I wouldn't rule it out. Regardless, the environment should be supportive of a few tornadic supercells across the area. How many and how strong they get remains to be seen.

Today could be more significant than yesterday turned out to be over the MDT risk area in LA. The amount of real estate covered by red boxes is reminiscent of some larger outbreaks, although the parameters aren't extreme.

NAM was a bit of a downer for IA chase prospects on Wednesday. Much less EHI than the GFS and doesn't develop the surface low up there nearly as much. However it's still early.

Already took Wednesday off to facilitate chase possibilities that afternoon due to potential being shown into parts of the upper Midwest (unfortunately my range will still be limited since I couldn't also get Thursday off and work starts at 3AM). Still, if the setup tanks you can blame me.

Holy smokes at the 12Z HRRR for the ARKLATEX Saturday afternoon/evening. Granted it is the far end of the range but even half that would be bad.

Trade ya for some of Dixie Alley's severe.

Let's all just take a moment of silence for the beauty of today's trough on the 500mb charts and what it could have done with a properly moistened warm sector. I'm thinking 54 years ago today redux wouldn't have been out of the realm of possibility (Although IIRC that one was even stronger, the max I can find today is 110kt while Palm Sunday '65 had >140kt if I'm not mistaken?).

Leaning against chasing northern IL on Thursday at this point. I would if the somewhat marginal moisture were the only issue, but despite the deep low and a >110kt jet at 500mb, it looks like all the shear will be speed shear so we'll end up with racing bands of storms. Even right ahead of the triple point, hodos on NAM forecast soundings are nearly straight-line. I'm also not seeing the steep lapse rates needed to overcome the sub-optimal moisture for a nice low-topped outbreak like early December, April 2004, etc. Better conditions at this time look to be further east along the warm front over IN/possibly SW MI. Still, it's a northern Illinois warm frontal setup so will continue to monitor, like the ones I mentioned those often don't look that great until the day of.

So far NAM and GFS are pretty insistent on southern WI getting into the warm sector with this...a far cry from the 30s with snow that was forecast for us as of a few days ago. Still they do seem to have a tendency to underestimate the Lake Michigan warm front blocker.

Absolute winner of a day today. Wednesday's chill and snow is going to suck, but it'll be more bearable since the snow and cold won't have been unrelenting well into the back half of April like last year. In 2018 I don't think we even had a decent stretch of 50+ degree days until the last 10 days of April, and then we pretty much flipped right to summer.

It just about did in the form of 4/27/11. See my earlier post for my thoughts as to why it was not unquestionably worse than '74.

12Z GFS now forecasts another Plains mega-bomb with 975mb over western NE by 00z Thursday, however winds are still northwesterly over all but the far western Gulf. Plenty of moisture however for epic snows on the north side wherever it's cold enough, if those totals are anywhere close to accurate the ongoing flooding problems aren't going anywhere anytime soon. By 00Z Friday things are looking rather interesting over northern IL. Rochelle redemption for me? Too soon to tell. That is if I can even dig my car out of the snow in time to go chase.

I weep for the potential of the system depicted on the 06Z GFS if not for the pesky lead system that keeps winds northerly over the western Gulf through 12Z Wednesday. Still worth watching how things evolve. I've made the mistake of writing off early season systems too quickly due to marginal/JIT moisture return and been burned (barely glimpsing an after dark tornado on March 15, 2016 after turning my back on the storm, sitting out February 28, 2017, also didn't take April 9, 2015 as seriously as I might have if it were in late April or May even though I don't recall moisture being a concern that day).

Yikes, totals anywhere close to that are really going to exacerbate the upper MS flooding issues. Sent from my SM-G955U using Tapatalk

Not a breath about this from my local mets so far. They're focused on the 60s forecast for Saturday through Monday.

While certainly featuring an inordinate number of very intense tornadoes, I agree the '74 outbreak was probably not as far ahead of its 2011 cousin in terms of tornado intensity as the official (E)F3-5 counts would indicate. Many of the violent tornadoes in the 2011 event, including several EF4s, did notably more intense damage across a greater portion of their path lengths than all but a few of the official F5s (particularly Brandenburg and Guin) in 1974. The only thing that in my mind keeps the 2011 event from being unquestionably worse than 1974 is the lack of coverage of violent tornadoes further north into KY/IN/OH. It was much worse for Alabama, however with the morning QLCS spawning a large outbreak in and of itself. To me, the ultimate outbreak would combine the coverage of the 1974 Super Outbreak (Dixie Alley through OH Valley into southern Lakes) with the concentrated tornadic violence that was visited on the 1st and 3rd of those regions in 2011 and on Palm Sunday 1965, respectively.

Say, -EPO, where abouts are you (general area is fine if you don't want to say exactly). You've mentioned in several posts your disdain for a northeast wind, so I'm guessing on one of the Lakes?

I hear ya, but still plenty nice out here and will be through the next week. Just a little quieter than I like to see in spring. At least it's not snowing! Hey, at least you can chase some high-based, pretty hailers this evening. If I was local I'd be all over that setup, but I'm not driving from WI to western OK for it even if I were on vacation!