Rain has tapered off to just showers as we have worked through the afternoon hours, and we will some some more showers into the evening and very early part of the overnight hours. As we move past about 10pm, cold air will start filtering in from the north, dropping temperatures quickly and rapidly for locations north of Interstate 20. It is in these locations where I expect the best chance to see rain change to snow and perhaps a wet dusting by the time snow ends by 3am at the latest.
For us to transition to snow, we need a few things to happen. First, our surface temperatures do not need to be below freezing, but we do need the atmosphere above the surface to be at or below freezing for a majority of it. If we warm above freezing for a large chunk of the atmosphere (like a mile), then the snow will melt before it reaches the ground, making the precipitation rain. If, however, we can keep the atmosphere below freezing and only have a small portion above freezing right at the surface, then we can get the flakes to make it to the ground. The temperatures tonight will play a big role if we even see snow make it to the ground.
Any snow that does fall will be the heavy, wet variety and will melt instantly on most surfaces. Cars that have not moved in a few hours, roofs, metal buildings, and some grassy areas may be able to get a light dusting, but that will be it. Roads will be above freezing, and temperatures should not linger below freezing long enough tonight for the water to freeze. The only exception may be a very highly elevated or long bridge north of Interstate 20. Temperatures tomorrow morning will quickly return to above freezing, so no travel impacts are expected.
The cold air will be felt the most tomorrow and tomorrow night. Thanks to a strong north wind, temperatures tomorrow will probably not get out of the 30s for most of us, especially locations north of Interstate 20, with the best chance for 40s being closer to the Highway 84 corridor. Temperatures Thanksgiving morning will bottom out around 20 degrees, making it the coldest morning of the year so far and coldest since December 2012. If we reach the teens for lows, it will be the first time since February 12, 2011.
We return to the upper 40s for highs on Thanksgiving, mid 50s for Black Friday, and 60s for Saturday with morning lows slowly returning to above freezing by Sunday. Our next chance of rain is not until Monday with a weak cold front sliding through the area.