Evening Update on Storm – Updated 1220 am

NEW:  All models in at 1220 am…it’s starting to look more like a snow event than an ice event in this model run, but that could be a temporary swing in the models.  It will all depend on the depth of any warm layer above the ground.

No change in anything really right now.  The NAM and GFS are similar in showing a Gulf low, significant precipitation (liquid equivalent 0.5″ in BHM, more south, less north), and a warm layer of air moving in at about 4,000 feet.  All models are in agreement on a winter storm in Alabama.

I’m sitting back and ignoring model precip types and exact temperatures somewhat for a minute (the difference in 33 for 5 hours and 31 for 5 hours can be the difference between a cold rainy day and a tree-falling disaster).  It looks like a situation where there will be snow on the northern edge, then a zone of a mix of snow and freezing rain, then tapering to just rain farther south.  The precipitation could be heavy, so the temperature will be critical. 

I don’t know exactly where the 32 line will be.  A lot of things happen at 32 degrees.  Rain freezes, releasing heat.  Snow melts, using heat.  I have seen it rain for hours and sit at 33-34; while 50 miles north of me it rained 1/2″ at 31-32 and hundreds of trees went down.  To pinpoint the exact location of that line now is not possible.  My best guess is near or just south of I-20.

However, I would say that it is now very likely that parts of Alabama will get a major winter storm on Sunday, with snow accumulations and some ice accumulations.  For Cullman and Gadsden, I’d say near 100%.  For BHM and ANB, 70%.  For TCL, Clanton, and Sylacauga, 50%.  MGM 40%.  There will likely be travel problems over north and parts of central Alabama. 

James will have a complete update with a lot more information in early in the morning, and I’ll have another update around 11 am tomorrow.

Category: Winter Weather