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Severe Weather Threat May 17-19, 2025

I'm going to call it now. Tommorow goes MDT and Monday gets upgraded to HIGH early-mid day 1 if trends continue.
Unless the LLJ for Monday is OMEGA verified, then as of right now, I don't see really much if anything that screams HIGH risk to me, after looking at the latest NAM and GFS run. MDT? Sure, but I don't see anything that warrants a HIGH risk. SRH/shear values don't scream "tornado outbreak" to me personally, same with the hodographs.
 
Going to note the entire dryline going through Ok is uncapped tomorrow at 0z, there just isn’t any forcing signal and very very subtle dryline convergence. With the level of instability and no capping forecast a fly fart could initiate a storm so I will be zero percent surprised to see wider/further south storm coverage than what is shown currently.
 
Unless the LLJ for Monday is OMEGA verified, then as of right now, I don't see really much if anything that screams HIGH risk to me, after looking at the latest NAM and GFS run. MDT? Sure, but I don't see anything that warrants a HIGH risk. SRH/shear values don't scream "tornado outbreak" to me personally, same with the hodographs.
While the SRH and shear is average, the CAPE, 3CAPE, and sharp dryline could make up for that. Hodographs on the 18z and 00z NAM looks good for supercells and tornadoes. Both the 3KM NAM and HRRR show numerous semi-discrete supercells and OWS supercells in an area of 6-12 STP. Lapse rates are decent, being in the 6.5 to 7.5 C/km range on the models I mentioned. Surface backing winds are from the south/southeast. On top of that, any outflow boundries left by storms later today could cause very quick tornadogenesis. Overall, I don't see why they can't go high risk.
 
Just stopped in Cameron, MO for the night. Current target is around Pratt, KS which is about 5 hours away should I should be able to make it by midday tomorrow. I might not have to move too far for Monday, but I would like to hedge a little bit more north (especially if southeast Nebraska looks like a viable target) to get a head start on the drive home.
 
Unless the LLJ for Monday is OMEGA verified, then as of right now, I don't see really much if anything that screams HIGH risk to me, after looking at the latest NAM and GFS run. MDT? Sure, but I don't see anything that warrants a HIGH risk. SRH/shear values don't scream "tornado outbreak" to me personally, same with the hodographs.

I haven't had time to watch through Trey's full video with Chris Broyles, so maybe these answers are in there but I'm curious if project OMEGA is fully operational yet, as in it's something all SPC outlook forecasters now use on a routine basis, or if it's something only Broyles and maybe one or two others use on an experimental basis.
 
While the SRH and shear is average, the CAPE, 3CAPE, and sharp dryline could make up for that. Hodographs on the 18z and 00z NAM looks good for supercells and tornadoes. Both the 3KM NAM and HRRR show numerous semi-discrete supercells and OWS supercells in an area of 6-12 STP. Lapse rates are decent, being in the 6.5 to 7.5 C/km range on the models I mentioned. Surface backing winds are from the south/southeast. On top of that, any outflow boundries left by storms later today could cause very quick tornadogenesis. Overall, I don't see why they can't go high risk.
Honestly I don't think people should trust the NAMNST when it comes to reflectivity. My question in terms of if a high risk is warranted, is if Monday has the capabilities of being an outbreak of 60-80+ tornadoes, or maybe even higher? So far, I've seen nothing that says that. And to be honest, if CAPE and 3CAPE mattered that much for tornado outbreaks (they do but not to a high degree), then today should've been generational, because there were CAPE values in southern OK that were almost off the charts, like I heard 6000-7000 CAPE values were observed in southern OK, and even past the red river in Texas.

I think in order for Monday to qualify for a HIGH risk, we need to see 0-1km SRH values to come up an extra couple hundred (total being 500+) and widespread shear rates between 60-65+ knots. If not that, then a VERY fast moving LLJ like what 4/2 had.
 
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I haven't had time to watch through Trey's full video with Chris Broyles, so maybe these answers are in there but I'm curious if project OMEGA is fully operational yet, as in it's something all SPC outlook forecasters now use on a routine basis, or if it's something only Broyles and maybe one or two others use on an experimental basis.
That's a good question. I would hope that Broyles would be able to get a piece of Monday's outlook so he can put his project to the test. With how well it's worked, I wouldn't see why others wouldn't use the LLJ study test for this Monday.
 
Honestly I don't think people should trust the NAMNST when it comes to reflectivity. My question in terms of if a high risk is warranted, is if Monday has the capabilities of being an outbreak of 60-80+ tornadoes, or maybe even higher? So far, I've seen nothing that says that. And to be honest, if CAPE and 3CAPE mattered that much for tornado outbreaks (they do but not to a high degree), then today should've been generational, because there were CAPE values in southern OK that were almost off the charts, like I heard 6000-7000 CAPE values were observed in southern OK, and even past the red river in Texas.
True. What I'm seeing to say a D1 HIGH is possible is mainly with the HRRR and its amount of supercells. I do believe that SRH might increase as we get closer to the event, however, as it has somewhat uptrended over the past few runs from 150-200 to 250-300.
 
Just a few things to note, it's interesting that many of the soundings are lacking analogs which can sometimes be a red flag for a setup. On soundings for this past outbreak, most seemed to have quite a few analogs. Using rough estimates from the 0z GFS it seems like the 500mb jet translation speed for tomorrow is ~32-34kts which is below the 40kts that OMEGA recommends for higher end outbreaks. There also seems to be negligible height falls for tomorrow's event. That being said, it still looks like a classic plains setup with a tight dryline and storm motion perpendicular to the dryline favoring a discrete mode. I just don't think its enough of a slam dunk for them to go with a High for tomorrow. Probably mid-high end Moderate imo.

However Monday looks scary. It seems to fix any problems with tomorrow's setup. It has stronger height falls, better diffluence aloft, larger warm sector, etc. I was having a bit more trouble estimating the 500mb jet translation speed and the best I could come up with was ~35 kts. Some of those smaller jet streaks seem like they're rocketing around the base of the trough, so it could be faster than that too. Overall, it seems like a more perfect setup that would give the SPC the confidence to go with a High. If I were chasing, I'd go camp out in SSE KS and would have pretty good odds of seeing a big tornado I believe.
 
Welp, we are in the last hour of waiting for the 2 AM update. Expect at least one of these days upgraded to MDT. There are only so many episodes of the big bang theory to keep me up at this point so I hope it comes quickly.
 
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