National Weather Service
An upper level low currently over the desert southwest will be digging into south Texas over the next 24 to 48 hours. A surface low is forecast to develop off the coast of Texas and track northeast and into the northern Gulf by Saturday morning. The 00z GFS is a little farther east and quite a bit faster than the 00z run of the European model by Sunday morning. Rain is forecast to spread north from the Gulf region during the day Saturday with the northern fringes getting into southern Middle Tennessee by late in the day Saturday. Rain across the Mid State Saturday night will exit during the day Sunday. Highs on Saturday are forecast to be in the lower 50s with lows Saturday night in the mid 30's. The atmosphere will be too warm for snow with this system in Middle Tennessee.
Image showing 00z GFS model run of surface pressure/precip fields at noon Sat Jan 16, 2010/NWS/Nashville
Image showing 00z GFS model run of surface pressure/precip fields at 6 am cst Sunday Jan 17, 2010/NWS/Nashville