A solid area of rain covers the southern half of Alabama early on this Saturday morning…
It extends as far north as a line from Linden to Selma to Montgomery to Tuskegee to Phenix City.
As expected, there has been sleet mixed with the rain along the northern edge of the precipitation shield.
About 1:45, the Cuba FD in West Alabama’s Sumter County reported light sleet mixed with the light rain, melting on contact.
JB notes the only reporting stations that have sleet right now is Mary Esther FL. Biloxi reported a mix earlier as well with temperatures in the lower 40s.
The good news is that the precipitation area is not moving north very much. It could be awhile before it gets to I-20.
Some light sleet may continue to mix with the light rain along the northern edge of the precipitation shield over Central Alabama.
In these observations, the second number for each station is the dewpoint. As precipitation falls and evaporates, evaporative cooling will occur at the rate of about 1 degree for every 3 degrees that the dewpoint rises.
It was 38/15 at Birmingham, 37/19 at Calera, 41/19 at Tuscaloosa and 35/17 at Anniston. It was 32/18 at Gadsden.
Vic Bell in Scrougeout reports 32/18 after a low of 31.
So doing the math, once precipitation starts to fall, temperatures could fall back to 30-34 degrees as the rain starts to fall in places like Birmingham, Calera, Anniston and Gadsden. A good indicator of where that might happen is the wet bulb zero line.
Even with temperatures slightly above freezing, bridges and overpasses will be colder and freeze before regular road surfaces.
WET BULB ZERO TEMPERATURE
The wet bulb zero temperature line extends from Reform – Jemsion – Phenix City. North of this line, it is still possible for temperature to drop to near or just below zero for a time this morning as precipitation begins to fall. It is in this area, north of that line that we caution there could be some light bridge icing this morning.
Did you know that wintry driving conditions kill more people in the U.S. than tornadoes, flooding and lightning combined? That is why we want you to check your local conditions and be very careful on bridges and overpasses, since they freeze faster than other road surfaces.
