jojo762

SPC already including southern KS and central/eastern OK in a Day-8 outlook for Friday April 21st.

00z and 06z GFS produced some truly ridiculous soundings across Oklahoma on Wednesday... Euro shows something drastically different, so nothing to get too excited about *yet.*

00z GFS continues to be pretty solid for sunday. Hate that the LLJ is WAY veered, but shouldn't matter too much. Solid BL-moisture, strong/moderate instability, strong deep-layer shear, and more-than-sufficient low-level shear. Best thing though? Storms **should** be discrete per model QPF output. Little concerned that BL and low-level moisture may become a bit displaced from the DL though, owing to the veered low-level flow. Also a little concerned about potential VBV issues, in relation to storm mode.

00Z GFS is incredible for Sunday from southern Oklahoma through central Oklahoma into southern Kansas.

00Z GFS is highly volatile along and east of the I-35 corridor next Thursday in S KS into OK. Both deep-layer and low-level shear are very impressive, instability is more than adequate, and moisture is probably doable, not to mention that it develops numerous what I assume would be discrete supercells along much of the dryline. Not too sold on what the GFS is showing moisture wise though with DPs barely reaching 60 along a lot of the dry line. Guess a lot of that will depend on overnight/previous day moisture transport and how far the boundary earlier in the week dives south. 00Z euro is slower than the GFS and much further west with the DL, but also very impressive from what I can tell... should be a fun ride building up to this... impressive seven days out for a march system.

Excerpt from D4-8 outlook: By Thu/D8, the trough and surface cyclone are forecast to deepen further, and at this point, appear to hold the greatest risk for severe weather. Moisture and instability will be a bit better than on the previous day, and the ECMWF shows a classic deep cyclone favoring all modes of severe weather, including tornadoes. However, predictability is low at D8, especially considering the current level of run-to-run model consistency. Thus, will defer to later outlooks for potential areas, which may eventually include the central and southern Plains, as well as the Missouri and mid Mississippi valleys.

The fact that the GOM will be open (at least the western half), and that we will we have southerly surface flow for days in advance is exciting... Still way too far out to determine very many details of any potential trough(s) though. Not a big fan of that H85 high that the GFS and Euro are showing over the western and north-central GOM though.

GFS seems to like the idea of an interesting system sometime around the 21st through the 23rd time frame across KS and the southern plains. Days of a relatively open GOM before hand would lead me to believe that moisture should not be too much of an issue. Biggest problem will probably be timing, as well as the potential for showers and crapvection in the warm sector.

For next weekend/ early next week, the GFS has been hinting at some days that would feature some pretty impressive conditions. Multiple waves coming through before the main dish. GFS has very little consistency with the main system, nonetheless timing is looking like it will be an issue. On a positive note, it does not appear that moisture will be an overwhelming issue, as of now.

SPC went with a broad brushed Marginal risk for Monday, which seems like a safe bet right now given wide model variability. Likely will see a slight risk later on. Given the strength of the wind fields, any forecast change in moisture quality/instability can alter the severe storm forecast drastically for any given area.

It's been hinting at this for several days now. Has had trouble figuring out exactly what time period it'll occur though. Think it is safe to bet a strong system will be effecting the plains sometime during mid-march, moisture return/quality of course is the biggest question.

Geez... I'd say so. Too bad it probably will not happen. 12Z NAM is about the best case scenario for severe storms/tornado potential that this system has.

Looks like Tuesday (2/28) is another potential event that fell apart as it got closer, basically nothing now on the models, at least for the plains. This was a theme last year, hopefully it doesn't become one this year.

Tulsa sure seems interested in the time period discussed above... " Our area will remain in the jet stream flow at the base of broad cyclonic flow over the western 2/3rds of the nation going into next week. A pair of fast moving waves embedded in this flow will bring thunderstorm potential to our area. The first wave will affect the region mainly Sunday night. What is different this morning compared to yesterday is the expected northward expansion of the warm sector in the wake of the weekend cold. The latest ECMWF suggests the warm front will lift north to around the Red River, leaving our area in the favorable warm advection/elevated storm region. Our area should be in the warm sector for the second wave Tuesday. The best chances for storms will be with the front late Tuesday/Tuesday night, though some potential exists during the day ahead of the boundary. The setup will be favorable for all modes of severe weather. The forecast could change, considering this is still 6 days out. Stay tuned to the latest updates as we get closer to the event."

Sure don't, at a glance it's a pretty incredible system for this time of year... If we get DPs around 60, somewhere, along with a slower system, things could really start popping with the current progged wind field. Something to watch, at least.

The system late next week (thurs/Friday?) looks to be interesting if we can get some decent moisture return after the Sunday/Monday system...

06Z GFS looks quite a bit better... And more comparable to the Euro, it also is a bit stronger with the S/W with winds at H5 at 50-60kt. VBV is more of an issue further north in Nebraska on the GFS than it is in KS/OK, but with southward extent the cap also gets stronger... Forecast soundings at hr 114 (00Z/ June 15) are very impressive along much of the dryline, with extreme instability, strong 0-6KM SHR of 40-55kt, and impressive 0-3KM SHR of ~30kt/0-3KM SRH of 200-300m2/s2....Euro has VBV, but it's only above 500mb, so maybe it is not as much of an issue...hopefully. Will be interesting to watch this evolve.

DDC AFD from this afternoon is pretty optimisitc about next week/this weekend, they appear to favor the ECMWF quite a bit...

yeah. some cluster just northwest of it. lol

22 0-3KM EHI... 22 STP. One of the craziest soundings i've ever seen, even from the 4NAM. This obviously won't happen, but its hilarious to look at.

Perhaps the best thing about the 12Z GFS was that the LLVL wind field is pretty impressive as early as 18Z, and by 00Z it is even better... Not liking the look it has had for several runs including 12Z of keeping lingering convection across much of the warm sector. Oddly, it appears to have little to no effect on instability or moisture. Still very little model consistency though in where the best threat area would be.

While there are still many things to work out, such as moisture quality, timing, etc, late this weekend/early next week continues to look interesting basing purely off of pattern recognition. Something positive is that both the GFS and Euro have started trending toward a less amplified trough (which would result in less meridonial flow) than what they showed a few days ago...That'll all come down to how far east exactly is the EC trough though.

I know that. I was talking about since they updated the Day 4-8. Like I said, I do not think I have seen a 30% since they made it to where there are two probability-categories in D4-8 (15%/30%).

So they did go with the 30% contour. I think since they updated the D4-8 to include two probability contours, this might be the first 30%?

GFS also hints at some other potentially big things coming in early May too. Hmm...