|Wednesday, May 5, 2010 - 11:46PM CDT
Plains forecast update IV for May 5
Posted 11:46PM Wednesday: 4KM WRF and GFS are out, and neither break out precip before dark in the preferred target area tomorrow. I've already decided not to observe storms tomorrow, but that new information simply reinforces the decision. As for the weekend and beyond, still looking nice as of tonight's 00z GFS run - but I want to watch another 24-hour model cycle before becoming more optimistic about a weather expedition. Still a lot of time for models to choke.
|2010 Storm Expeditions - Probabilities as of May 5|
Posted 9:31PM Wednesday: Have pulled the plug on tomorrow's expedition, partially based on the 00z NAM not breaking out precip by evening, and partially for economic reasons. Tomorrow may be a good day if the cap breaks early on and if moisture can improve better than forecast - a chance that would be worth taking for those on chase vacations and those with big chase budgets. But for me, after an active early season, I have to be careful about depleting spring chase funds too soon (I don't have an unlimited travel fund). With it still being early May, I think the money may be better spent on later trips.
Posted 2:30PM Wednesday: Bumped up the probs for late weekend into next week, as confidence for a Sunday-Tuesday Plains expedition has increased - thanks to the Euro beginning to kick the trough eastward a little more. My main reservation against being more optimistic is the tendency for model flip-flopping 5 days out.
Also am liking tomorrow's setup in eastern Kansas. This one seemed to come out of nowhere (I wasn't paying much attention to it), but there isn't much to not like about it at the triple point - good upper support, backed surface and 850 winds, decent instability, a cap to hold off storms until evening. Pending the morning's dewpoint situation (and attendant likelihood for pre-sunset convective initiation), I may head out to observe storms.
Posted 5:17PM Tuesday: The GFS and European models have been agreeing lately on a western trough configuration returning southwest flow aloft to the Plains by sometime this weekend. Sunday through Tuesday show some promise for storm setups from Kansas into the Texas Panhandle. Capping may be an issue on one or more of the days, as well as the Euro hinting that the trough may remain too far west or north to send strong flow over the deeper moisture. That and the number of days in the future we're still talking about, leads me to not go much higher than 50 percent on chase probabilities. I'll go into more detail in the coming days after there has been more time to watch how the models handle the pattern.