andyhb

The threat on the weekend over the N Plains towards the Upper MS Valley might be thread worthy as we get closer. Seems like another anomalously strong trough (00z Euro had an 80 kt 500 mb max with this thing) will be traversing that area come Sat-Sun with potentially a sub 1000 mb surface low and a strong LLJ response. Moisture will have recovered in all likelihood over a large area by that time too.

Seems to be the suggestion of a rather strong shortwave trough dropping SE out of the Gulf of Alaska towards the early part of next week via the deterministic guidance (supported a pronounced lowering of the heights across the Prairie Provinces and N Plains on the ensembles in this same timeframe). Northern stream has been quite active this summer so this doesn't seem to be too farfetched. Does seem that there may be some low latitude troughing that could cause problems with moisture availability though.

No.

Quincy is on that storm and he said nothing confirmed yet, did have a funnel cloud/rotating wall cloud though. Edit: Nvm, just confirmed it.

Looks like a cluster of cells trying to consolidate near Tecumseh, NE.

91/76 at TOP right now, pretty juicy to say the least.

These types of events with subtle waves cresting a ridge and neutral/even rising heights during the day are always tricky. I'd lean more towards the messy idea although the dryline does seem to be available for convective initiation this time, which is often the downfall of these kinds of setups where everything south of the warm front is capped.

BTW, good on whoever got the MBX radar up and running, offering much better looks at this supercell than using the Canadian radars in the area.

Large, multiple vortex tornado in progress in SW Manitoba near Melita currently.

Supercell developing near Long Lake, SD might be able to do something if it can right turn and interact with the OFB to its south. Edit:

Environment is pretty nasty INVOF this cell. Cone tornado near Artesian recently.

SD proving why it is the best again...

Models seem to be toying with the idea (particularly the latest 12z Euro) of ejecting a very impressive upper trough and associated anomalously deep surface low (sub 1000 mb) across the N Plains/S Prairie provinces early next week (looks to be around the 27th) with a seasonably moist warm sector out ahead of it. Would have to think there would be at least a half-decent severe weather threat with that, given you really don't see systems that vigorous this time of year at all.

Looks like a pretty strong book-end vortex NE of Hill City, KS presently, although it's difficult to see from any of the radars.

Looks like the outflow is surging out ahead of that storm. Tornado potential should be low for now.

All of this going on with no tornado risk area in the 20z outlook. I am having an increasingly difficult time believing many of Dial's outlooks. They have been weird for a long time now.

About to have a problem moving into Overland Park. Damage reported in Eudora.

TDS on it too.

Slight risk today.

Tornado confirmed on the storm near the SD/ND border north of Buffalo: https://twitter.com/Wx_Dan/status/616056420618768384

Looks like a localized tornado outbreak ongoing over E ND and W MN right now.

Yeah that whole idea fell apart fast. Looks as if we'll go all of Spring and June without a high risk or PDS watch at this juncture.

Just a few thoughts about the 00z guidance (focusing on the operationals): There are two camps in this set of model runs. One, consisting of the Euro and GGEM, is more progressive with the closed low that breaks off the main northern jet branch in the NW in a couple days (this is mainly due to it not retrograding west as far) and eventually leads to a rather messy, disjointed troughing across the N tier of the CONUS late next week since the aforementioned low does not phase very well with the incoming southern stream that undercuts the Aleutian ridging. The other, potentially more volatile scenario is shown by the GFS and likely an extrapolated UK. These two model retrograde the closed low far enough so that it is not picked up by the northern stream for a slightly longer period of time (both in a similar position at 144 hours). It then (on the GFS) is picked up by the northern stream afterwards and phases with the southern branch more effectively, eventually leading to a very potent shortwave trough ejecting across the Northern Plains around D8-9 with some extremely impressive wind fields for June (and likely higher end severe potential as it seems a large reservoir of seasonably high instability will be in place for whatever does come down the chute then). In conclusion, while it seems all guidance would indicate at least some severe possibilities late next week (as they have for several days now), it's going to be crucial to monitor the evolution of this closed low off the West Coast over the next few days as it could have major implications downstream for the northern CONUS. Should also add that the northern stream shortwaves that eventually lead to the closed low being picked up are also highly important. Overall, a lot of moving parts and it should be awhile before anything is settled on.

Some of these longer range GFS/ensemble runs as of late have really fallen into the "holy crap" category.

Man 18z GFS has a trough with a 90 kt 500 mb and 120+ kt 300 mb speed max moving across the Northern Plains next week, that would be seriously impressive.