We just wanted to provide a brief update on a somewhat challenging forecast for tomorrow.  The forecast currently calls for locations across portions of central and north central Texas to experience a wintry mix of sleet and snow Friday afternoon into Friday night.  Not much in the way of accumulation is expected…in fact many parts of central and north central Texas may not see any wintry precip at all…but conditions will be present for at least some chance of seeing a few sleet pellets or snowflakes mixed with light rain as we head into the afternoon hours.

An upper-level disturbance will arrive across northern Mexico into west/southwest Texas by tomorrow afternoon which will generate widespread lift and light rain from west to east across southwest, central and north central Texas.  It will also be dragging some Pacific moisture along with it in the mid to upper levels of the atmosphere where temperatures are forecast to be between -10 and -20 degrees…which is perfect for the development of snow crystals, or “dendrites”.  The trick tomorrow will be how quickly the dry post-frontal air closer to the surface can moisten up and allow frozen precipitation to reach the ground before sublimating…which is basically the phase change from a solid (ice) to gas which happens to ice crystals that fall through very dry and cold air.

As the day wears on, we should see the atmosphere begin to moisten from the top down allowing at least some of the wintry precipitation to reach the surface.  Across central Texas, this is expected to fall primarily in the form of light rain mixed with some sleet from mid-afternoon into the evening hours.  Across north central Texas, we’ll be more likely to see light rain followed by a mix of sleet with light snow into the evening and overnight hours.  All amounts that fall are expected to be light with very little in the way of accumulation to muck up the roadways.  We can’t rule out a few heavier bands of sleet or sleet/snow, but overall there should be no widespread travel impacts.

Regardless of precipitation chances, highs tomorrow will be quite chilly and a good 15 to 20 degrees lower than what is typical for this time of the year.  On the bright side, we’ll be warming back up to more seasonal temperatures by the start of our next work week!