WxSynopsisDavid

Confirmed tornado by weather spotters, north of Kosse

That is a rather impressive increase in dew points in short order.

Perfect, instructive video to show the public that when the NWS or us forecasters warn of a tornado, there is a reason we say "seek shelter". That means away from windows, doors, exterior walls, etc. and in an interior room like a closest, in a basement, or a storm shelter. Your life is not worth the picture and video, going viral and gaining "5 minutes of fame".

There is a few noticeable trends I'm seeing leaning towards the prospective of a more significant threat. Previous NAM runs struggled to present any sort of mechanism to fire convection east of the dryline. NAM seems to be more vigorous with the surface low coming out of the southern plains and has it deepening to 988mb. The pivot of the low cutting north is timed right when the trough orients negative. Convection looks to fire around sunset or after along the dryline. Not liking the timing of that because it suggest bulk of convection holds off until near sunset when the cap is breached, when the LLJ cranks. Though there will be convection across the lakes on Tuesday, it looks as if this is becoming more of a Wednesday event.

I say that I would love to see them, because I’m a storm chaser based in the Mid-Atlantic. I have come close a few times chasing here in VA though.

Dude, absolutely impressive. You and every other chaser out there did great on the pictures and videos. I would love to witness/experience twin tornadoes.

Yeah, like i said earlier, the NAM suite has been off this storm season. It was horrible with the last 2 outbreaks and outperformed by the other models. Its doing the same thing, like you said, it did with yesterdays outbreak.

Agreed. Between mixing, LCL's, morning convection, capping inversion issues this is something we wont know until the morning of, in terms of SPC issuance. But this is the strongest synoptic signal we have had for a severe weather outbreak since 2011 over such a large area/expanse of the US. It's shaping up to be a conus-wide outbreak.

Looking at the GFS, these are high end Supercell Composite values being we are 80hrs out. The size of the warm sector is unreal.

New Jersey

The one good thing here is we have a few fail modes being presented. In all honesty, that is digging for something positive right now because the current fail modes still yield a sizeable outbreak.

Looking at the soundings, they are all high-end upper echelon type stuff. If you get past the small issues the NAM has been dealing with this year, those NAM soundings are still high end. As has already been discussed, the main issues here at this point remain: mixing, LCL's, early morning convection, capping inversion issues. Should those issues materialize, the floor would be yesterdays event. If we do not have any of those issues come Tuesday, this outbreak "COULD" rival the scope and magnitude of some of the bigger outbreaks we have seen. I know a lot of people on Twitter been throwing around 4/27 comparisons for size, and its very plausible the warm sector gets into southern Canada, its important to note for size/magnitude that can be debated. Everything else, no. Yesterdays event was close to some degree, a smaller "notch down" carbon copy of 4/3/74. Same areal coverage, same upper air support, but not quite on that level with violent tornadoes. I will say that I am more concerned for this upcoming outbreak than I was with yesterdays...and I still had concerns, not just as many as I have for this next one.

NAM suite is suggesting a strong cap in place in some areas that don't get breached until right before sunset. This would need to be monitored as it would suggest, if parameters hold, this would be a nocturnal event.

Absolute textbook of an embedded hook echo. Very rare to see this signature in the northeast.

There were similar trends at this range for the 3/2/2012 and 4/27/11. But you are right, this doesn't happen often and its rare.

Yes it did, it was probably the most accurate in terms of how it depicted the warm sector and the airmass recovery between the waves of discrete. Also, while other models were trying to congeal the stuff quicker to the south like in Arkansas, the RRFA kept everything discrete or semi-discrete. The helicity swaths it outputted yesterday morning was almost a carbon copy of what was experienced. The HRRR has also done great with these last 2 outbreaks too.

Important to note that the NAM suite was horrible with yesterday's outbreak and was also horrible leading up to the Rolling Fork incident. NAM suite has been getting out-performed this year.

Radar velocity scans were showing 3 couplets with TDS. That was a potential trio, one of them would of been rain wrapped.

We are all focused on the current, on going major outbreak. There will likely be no post made until after this current outbreak is over.

Confirmed by Brandon Copic, dual tornadoes on the ground near Keota

The 00z HREF spits out a “super outbreak”. Curious to see the next updated HREF run.

09z RRFS-A and 10z HRRR helicity swaths

10z HRRR

09z RRFS-A is insane, don’t really have the words to describe that scenario. About as high end as you can get. Even tries to get some supercells going out east from northern VA up into PA.