andyhb

Been watching this elsewhere and that is absolutely an historic derecho for Iowa. Extreme high end gusts (and a lot of them), the duration of damaging winds, it tracking through the most densely populated corridor in the state. Not sure I've ever seen such a duration of 100+ kt returns with any single derecho as I saw with that (from both the DMX and DVN radars). I'd have to imagine some of the reports from outside the bigger cities like Cedar Rapids, Iowa City, and Des Moines are going to be frightening. Particularly in the region along US 30 and I-80 between Des Moines and Cedar Rapids (Tama, Marshalltown) and also NW of Des Moines near Madrid. Can't imagine what Iowa State and the UI campuses look like right now, but I'd imagine it's something along the lines of a war zone.

New TDS west of Springfield.

This might help.

The last several weak Ninas (1996, 2002, 2006, 2009, 2012, 2017, 2018) haven't exactly been promising for severe season either with quiet Mays and Junes for the most part. Would be a real downer after this year went completely down the drain post-April.

Still needs to spread west more if we're going to get a stronger event.

The AA precip over almost the entire Gulf suggests a quiet Gulf?

That shortwave that ejects into the Plains behind it is at a pretty low latitude and it quite strong for June. Would think there could be a considerable severe threat with it assuming the two are separated by a decent degree. CIPS analogs are loaded with big events, but obviously there's a wrench in there with Cristobal.

Curious as to the severe potential with this once the more tropical thermodynamic profiles are somewhat muted into Wednesday. Anomalous wind fields at all levels and plenty of low level moisture would indicate the potential for a pretty significant squall at the very least. A lot of things depend on the speed of Cristobal through the area.

Fixed.

Amphan in the Bay of Bengal up to Category 4 status, rapid intensification occurring.

3 km NAM joins the party near the Capital District into S VT. Can't say you pull area-averaged soundings like this too often up there.

Pretty solid agreement from the 00z convective allowing models (HRRR/ARW/NSSL) for a few supercells in upstate NY and then tracking along the MA-VT/NH borders later. I'm not a huge fan of the relative lack of steeper mid level lapse rates, but at least low level lapse rates are half decent leading to some rather large 0-3 km CAPE. Good wind profiles as well, wouldn't sleep on this setup up there.

Wednesday next week looks like a good opportunity for slow-moving supercells, sign me up.

Not that the upcoming pattern for the next week or so will be great for severe prospects, but this is indeed getting a bit repetitive. Two days after you posted the bolded, there was a localized tornado outbreak along I-35 in S OK that was probably the best April chase day in a portion of the Plains in awhile (along with more tornadoes on 4/24 in SE OK/NE TX).

Storms moving at the speed of light would be number one regarding chasing. I do think there’s a pretty strong possibility this stays mostly discrete until the evening though. Would maybe like to see a bit more turning in the lowest 3 km and a bit more instability, but I’m inclined to think that the arcing Pacific front/pseudo-dryline, in addition to the triple point in IA early on, should be a breeding ground for supercells. Tornado potential dependent on how the low level wind fields evolve (and how fast the deep layer cyclone occludes).

Why do you keep tagging me with the weenie emoji?

Definitely a few similarities with the setup that yielded the deadly TN tornadoes on 3/3. Strong westerly flow aloft with similar hodograph structure and I'm going to bet that the NAM/NAM 3 km are too cold at the surface. Any southerly component to the surface wind will yield large 0-1 km SRH when your 850 mb jet is 50 kts out of the WSW.

JISAO PDO is no longer being updated. Also, the +AO has reached an all time record daily value at 6.34, surpassing 2/26/90 at 5.91.

Getting increasingly concerned that the strongest low-mid level FGEN and vertical ascent may set up right over the I-44 corridor in OK and N TX with this. Someone who stays cold enough is going to see 12-18”, which, for here, is crippling. With that said, the 3 km NAM seems stubbornly persistent in its idea of really suffocating the band before anything really gets going.

As is tradition, let's give our calls for how active the first tornado season of the decade will be. Looks like we'll be heading towards spring with weak positive ENSO and roughly neutral PDO, in addition to a lack of drought over most of the area east of the Rockies. I have a feeling like we may see another A/AA season given some of these climate states, but obviously sub-seasonal activity will again be key. Will have more analysis later. Number of tornadoes: 1310 First High Risk: 4/18

At this point I’m just looking for an email to recover my password.

Ditto this situation.

Early June has been very quiet for most of the 2010s, the exception being 2010 itself. I definitely think the latter part of next week will have a chance beyond the amplification of the ULL near the Great Lakes. There is a strong signal in the GEFS for at least some activity in that period (and there has been for awhile), and note that the GEFS SCP chiclets on Gensini's website are anomaly based, rather than using raw count, so it gives a better idea of elevated activity relative to climo. Signal on the EPS is rather nebulous, but I wouldn't expect a really large signal in the heights at this point since it looks to be more centered around subtle disturbances in the flow.

Paul Roundy was my OU advisor's phD advisor. This is another shot across the bow regarding this upcoming severe wx season.

@raindancewx I saw you post the TWC spring outlook elsewhere and am curious as to why you don’t agree with them for May/what your general thoughts for May are (for obvious reasons).