Saturday, April 25, 2009

Searching for the needle in the haystack...

Well, I'm not in Oklahoma. Or on my way. With my schedule this weekend, I'm free to chase both today and tomorrow but just didn't find it feasible making it to OK in time without putting my car in a ditch first. I'm bordering on worried about HP nature of supercells in that area today, which could be somewhat frustrating especially if the show is primarily nocturnal. Anyway, certainly worth a shot though as I'm sure we'll see some intense stuff come from the chasers in that area this evening.

My target today looks like west-central Illinois. Certainly more of a wait and see effort on this side of things as boundary interactions will play a huge role in getting anything worthwhile. On the whole, it could be a lot worse. Mid-level winds are lacking, but could be made up some by some good storm scale boundary interactions. Cape will be adequate for the first time this year, with surface based cape values 2000-2500 j/kg not unheard of. A weak wave may develop in Missouri today which should help keep surface winds southerly, which is a drastic improvement from the west-southwest flow earlier models had shown. Winds in the low levels continue to be adequate with a 40-45 knot LLJ across Missouri and Illinois. Helicity values are very low, however taking a closer look these values are taking into account an almost northerly, northeast storm motion today. Given the overall setup and east-west boundary I think a more east-northeast storm motion will be seen which may also improve helicity values some over the area.

An early look at things shows the cold front currently located along a line from Milwaukee to Kansas City. There likely won't be too much southward motion of the boundary this afternoon. A cluster of elevated thunderstorms has exited the target area, and is now lifting into northern Indiana. This cluster could have been key in laying down a very useful boundary this afternoon. In it's wake clear skies have given way to rapid surface heating with temperatures already in the lower 70s with dew points within a degree or two of either side of 60F. There is little capping in place today, so I'm weary of too much more convection being generated either along the cold front or on the outflow boundary from the early morning convection. I'd like to see things hold off until around 2 PM when we've had at least a few hours of adequate surface heating.

Overall, I think the general "area to watch" outside of the main event in Oklahoma will be east-central Missouri into west-central Illinois. Perhaps anywhere along the long line from Columbia, Missouri to Springfield, Illinois. I don't expect a very big day, but a few "surprise" tornado reports don't seem out of the question. I intend to attempt my best at being in the right place at the right time for those surprises.

EDIT: On a side note regarding my live streaming partnership with WDT Inc., CNN will be demo'ing use of the live streams during their prime time broadcasts this weekend during the severe weather event. While I'll be chasing the boring side in the midwest, I will be running the stream to help with the demo either way. Feel free to pop in and check it out on my live page, here:

1 comment:

Karen Heise said...

Andrew, I did check it out. It looks pretty cool. I've been fascinated with weather for years, and thanks to Eric Nguyen and others like him, I've come to love it even more. Found your info about the "status" of the chasing community a little disappointing, and I can see why you're doing what you are. This is never about the chaser, is it? It's about the weather, and helping people out of harm's way. How quickly we forget that.