A new year, a new chase

So I suppose it's about time I blogged here, detailing the travels and travails of this year. This year, we're heading out on a trip that will last up to 10 days (much likely fewer than 10 days) in search of the rotating atmosppheric violence for which so many of us clamour. Okay, after that lame attempt at prose even I'm ready to punch myself in the face. But still. We start out on Saturday. This is out of necessity due to scheduling made well in advance, but it looks like it could end up working for us. Friday (May 18) looks marginal, at best, as although moisture and, as a result, CAPE, are progged to be good over the northern plains and southern Red River Valley (of the north, or "the *real* Red River Valley, as an SPC forecaster friend of mine calls it), the NAM and GFS have been consistently painting dewpoints way higher over the continental US than reality has shown. As it sits right now, as I type this, dewpoints (hereafter called "dews") are struggling to get into the double digits (C) in Kansas. KANSAS! So any return of moisture would have to encompass a) an open Gulf of Mexico and b) a strong low-level jet (LLJ). So to begin, let's look at those: the LLJ and moisture. I present to you the NAM 48-hour forecast of dewpoint and wind at 850 mb and the surface. Note that a) the Gulf seems to be open and b) there are 2 distinct areas of moisture, one in the northern plains and one stretching as far north as Kansas. I posit that the area of moisture as far north as Kansas is the *real* return flow, and won't make it in time for convection to be more robust farther north. I will also admit, though, that I have a bet with Justin right now that the dews won't reach 15°C anywhere in Manitoba on Friday. I hope to win said bet.

Anyhow, to beat the hell out of this dead horse, I think that moisture is overdone, badly, so I doubt there will be any major league severe in the region Friday. Now onto Saturday. The beginning of our chase. I feel almost that I should make a "ta-da" sound, or at least make the Imperial Margarine crown appear. But you won't get it; I'm just that kind of guy. Anyhow, we're looking at departing from Winnipeg and trying to make it to the zone of terror. In this case, it appears the farther south, the better. Keeping in mind the craptacularity of moisture being handled in the NAM, we will cautiously look at the trough/convergence line stretching from the progged low in northwest Ontario to the other one in the northeast Texas panhandle. Flow should be not too bad at midlevels, with winds on the order of 30 to 40 knots from the southwest, juxtaposed (I like that word!) with surface winds out of the south.

The NAM does make a convective signal happen, with showers and thunderstorms between Dodge City and Wichita, KS by 3Z on Sunday morning. Is this real? Beats the hell out of me, but with the prog sounding and wind profile, it sure looks promising.

Here's a problem, though: have you ever tried to drive from Winnipeg to even Kansas City? It takes a few (read: MANY) hours. So that's an unrealistic target. So Saturday may, by necessity, end up being a positioning day for us, all while watching storms go up and nothing we can do about it. We may, however, be able to catch something, say, close to Omaha, where similar instability but not-so-backed winds are progged. That's at least a realistic chance.

The 17/00Z GFS, for what it's worth, produces better conditions farther north than does the NAM. We will see, but it appears we will only be able to chase this stuff, if anything at all. Sunday looks only okay at this point. It appears that the trough causing all the awesomeness on Saturday will move east Sunday, leaving only some places for storms, the best of which appears (at this time) to be northeast Oklahoma. The wind fields, however, aren't forecast to be great--multicell, if maybe marginal supercell. Monday looks like a returning flow day in north Texas (Wichita Falls?) or maybe on the caprock. Tuesday looks pretty good for the western plains, be it Nebraska, the Black Hills or western North Dakota. If I had a better confidence in moisture I would be jumping up and down about this day. The good thing I see is stronger winds on the west side of the upper trough, which leads us to... Wednesday is a damn fine day, if the GFS is to be believed. The *digging trough* (referenced above) will cause lee cyclogenesis out over the plains, and the response should be good. This will be a forecast based on convection, if any, the previous night and its resultant outflow, juxtaposed with the good (50 knot) midlevel flow. After this point, I feel it's a losing battle to even try, but I will say this: a week ago, the GFS had a death ridge over the area of interest, and at this time, for the same time period, now it does not. Anyhow, let the season begin It's about time.