Cut-Off Low, Cold Front Should Bring at Least a Bit of Rain

I've delayed, and delayed, and delayed on forecasting this system, because frankly I don't think anyone knows what's going to happen. Model consistency has been ZERO, even up at this late hour. You'd think they were trying to handle a winter Nor'easter or something. The GFS first showed NE TN under a pocked of 2.5"+, now it's the NAM's turn. And if you want to give up on forecasting it by yourself and stick with the HPC's call, good luck. 00Z outlook called for up to 4.5" in NE TN; 12Z drops that to 1.75"-2". This all combines into one big mess. Period. MRX (Morristown NWS office) has had the same struggles. Frankly, I still think they're underdoing it, but then again they're actual meteorologists with degrees in this stuff.

To cut to the chase, both the NAM and GFS call for a cutoff low over Texas, filtering Gulf moisture into the area. Showers and thundershowers develop well-ahead of a cold front Tuesday. The cold front swings into the area later Tuesday, possibly early Wednesday. After that, you can kiss consistency goodbye. The NAM's solution is certainly what I want to happen, and may be realistic. It calls for quite a plume of rainfall to move in along with the front, dropping as much as 2" in a six-hour period. That may be a bit flamboyant, but certainly better than the GFS, which is about as pessimistic as you can get. (unless you count the 12Z NGM ) My call is for numerous showers and thundershowers late tonight and tomorrow, with more solid, moderate rain late tomorrow and Wednesday morning, as the front moves through. Showers linger for the rest of the week. Totals could range from a half-inch to 3". (lesser amounts likely in Western NC) Why such a broad range? Again, there's still uncertainty involved here.

One final note: A *WIND ADVISORY* is in effect 12 PM EDT Tuesday for the Smoky Mountains and its foothills, including mountainous Greene County.


Ugh. That's it, that's all, I'll update in the morning. Peace, love, goodnight.

10/22/2007-10:11 PM