Sunday, January 17, 2010 - 9:41PM EST   
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First thunderstorms of 2010?
Update Tuesday 1/19: Looks like our first storms may actually arrive here overnight tonight! I had written off Wednesday's potential due to limited instability concerns, but it appears as if we'll get at least enough elevated CAPE for some lightning.
Originally posted on Sunday: The GFS model is showing some moisture return off of the Gulf starting this week, with a strong system taking advantage of it around Friday-Saturday. 50s dewpoints are shown making it nearly to St. Louis on Saturday, with a decent wind field from the surface to aloft. A big slug of heavy precip is shown Saturday. All of this suggests at the least, some lightning; at the most, a severe weather event. As with most winter setups, better chances for both increase toward the south.
GFS dewpoints for Saturday
Climatology doesn't favor much happening with this, and I'm a little skeptical of the Gulf's ability to produce the advertised moisture returns due to its repeated water temp-lowering arctic air intrusions as of late. We'll see if surface obs and soundings in the coming days show any moisture of a useful depth actually coming onshore. After that I'll know how optimistic I should be.
I think lightning at home may be a good bet - a great first use of all of the 360-degree sky views at my disposal. At any rate, this is the type of system that living in the lower Midwest will improve my chances of seeing anything 500% more over living in WV (without having to leave home, that is). Gulf moisture surges in winter-early spring usually have few problems making it to STL and points north - while the southern Appalachians typically cut off the higher dewpoints as the southerly surface flow moves eastward.
