1/18 – Rob Knight’s “Up & Down Temperatures” Tuesday Afternoon Forecast
Warmer temperatures overnight as the winds will become southerly along with increasing cloud coverage.
Moisture levels will continue to increase Wednesday in advance of an approaching cold front. During the day Wednesday, convective development will be rather limited as even with dew points gradually rising into the mid and upper 50s. Temperatures climb into the 70s on Wednesday, but will dive with the passage of the cold front prior to sunrise Thursday.
This sets up the potential for problems Thursday night as the next disturbance approaches from the west. This will be an overrunning situation as warmer air in advance of the shortwave gets pushed up and over the shallow frigid air mass. Surface dew points will fall into the lower and middle 20s north of Interstate 10 Thursday night as the cold and dry advection will be in place. The question will be the placement of the precipitation and how far down evaporative cooling pulls the surface temperature. While most precipitation is likely to remain offshore, there’s at least decent potential for measurable precipitation overnight Thursday night into Friday morning. While areas generally south of Interstate 10 are likely to remain above freezing, areas to the north could see the potential for light sleet and/or freezing rain.
The rest of this weekend looks pretty quiet. Cool, but quiet. Surge of main upper weakness coming out of Canada and across the Great Lakes will shove all the Friday precip offshore. Temperatures will be 10 to 15 degrees below normal with Saturday being the coldest. That day, highs will struggle to reach 50 degrees anywhere in the area. Combine that with breezy conditions you’re looking at afternoon wind chill values near 40 degrees.
A HARD FREEZE WARNING may be necessary Friday night into Saturday.