Here we go again…

Tomorrow is going to be an active day. The dynamics of this system are huge - a ~982mb surface low will slide into central Nebraska, and with it bring the forcing needed to get this juicy air going. Here in northeast KS, the earlier concerns have been resolved: namely the surface moisture: the last system really flushed it out (temps dropped to 30° overnight last night in the dry environment!), but it has rebounded nicely as expected, with Tds in the mid- to upper-50s this evening. A month ago this would have concerned me, but since 3/12 - not only with that event, but several since - I have learned to not be surprised by the quick moisture return that can happen in a single overnight once the LLJ fires up!

Comparisons have been made to 04/11/2001 and, while I could not recall that particular event, upon viewing the surface map and the SPC storm reports pages, I can see the similarities: A particularly potent surface low and two distinct targets - one north, one south.

I see this system playing out with two main targets - one being the first initiation to the north: near the triple point, the other being the southern end of the line that fires much later in the afternoon/early evening. The best surface convergence certainly is not here in KS - we’re sandwiched between the best targets, in my opinion, in a region lacking the best directional shear - an essential ingredient for tonadic supercells. First, the northern target.

If I could chase, I’d love to spot the eastern NE target (~LNK to OFK) if for no other reason but the s l o w e r storm motion vectors. Several of the big events so far this season have have been headlined by storms that were flying at 50 to even 75 mph! Regardless of how good the road grid is, that is tough to chase. Storms that fire along the dryline bulge tomorrow here in Eastern KS, Western MO, and even more so the targets in OK and AR are going to be cruisin’. Instead, I’d like to be on the northern target where storm motion will be a more reasonable 25-35 mph.

The dynamics are going to be wild in Nebraska with such a strong surface low, but with that comes some degree of uncertainty with the winds. It isn’t unheard of for these targets to be a bit of a bust in terms of a significant tornadoes due to wind shear that shreds the cells before they can get deeply rooted. Additionally, the window of opportunity for the northern target is somewhat limited to about a 6-hour time frame stradling the mid-afternoon, shutting off completely when the low continues to stack vertically, losing the needed large-scale dynamics, no to mention that show will shut off quickly once the daytime heating is lost. On the upside, moisture convergence is good and the nice upper level divergence created by the exit region of the jet progged to be in place ~18z.

In terms of Eastern KS, the threat is very real, although it won’t be the region of the best dynamics. Storms dancing along the surging dryline bulge will have to be well-timed to hit the best of the dynamics and luck into some localized enhanced directional shear, but that wouldn’t be surprising. I think the focal point - the centerpoint - of tomorrow’s storm reports will be to our North and South though.

The later and more southern target looks a bit juicier in far eastern OK into AR and also including much of MO. Where supercells quickly fire from clear air and blast ENE, there will be a good evening show into the early overnight hours. I haven’t focused much attention on this area, but am far from discounting it. I feel the TOR threat is higher for this area than the northern target, at least in terms of an outbreak per se as this show gets going later in the afternoon and is likely to include several discrete and deeply-rooted supercells that pop from clear air.

While I’m not completely sold on the need (or rather the justification) of a HIGH risk for tomorrow, I wouldn’t at all be surprised to see that show up with the first Day 1 Outlook overnight.

I will not be chasing as I’ll be working through ~4pm and am simply not geared up in chase mode yet, but will be doing what I can to stay on top of the situation. All this, and the real front won’t even pass until Friday. I’m still learning the dynamics of the dryline, and they are fascintating.