A complex winter weather scenario is beginning to play out this evening across the Hill Country and South-Central Texas. I won’t bore you with all the technical doo-dads so I can keep this short and sweet. Temperatures are going to be a tad cooler tonight than previously anticipated. This isn’t totally a surprise but will require a few forecast adjustments for tonight. The first of which is to extend the Winter Storm Warning east to Interstate 35 to include both the Austin and San Antonio metros. I want to stress it looks like the freezing line will be on the western edges of Austin and San Antonio during the morning hours on Saturday. That means the eastern parts of the cities may end up only seeing a little ice on elevated surfaces while the western parts of the cities and points west could see more significant ice accumulations on roadways and elevated surfaces. I want to emphasis that the worst travel impacts should still remain JUST west of Austin and San Antonio proper based off the latest high resolution data but its going to be close. If that freezing line moves 5 miles further east than all of Austin and all of San Antonio will have more substantial issues with ice accumulation. The most significant ice accumulations (up to 0.25″) will occur west of Interstate 35 in the Hill Country where the heaviest precipitation will fall in areas that are below freezing. With all the cold weather over the past few days it won’t take much for ice to accumulate on surfaces.
Here is what the latest hourly run of the High Resolution Rapid Refresh (HRRR) weather model is showing for Saturday morning. I think the graphics are fairly self explanatory and depict the overall scenario quite nicely.
Finally here are the local forecasts from the National Weather Service offices in the impacted regions. I do want to note that temperatures are expected to climb during the day on Saturday but another round of winter precipitation could impact North and Northeast Texas Saturday Night into Sunday Morning. That does not look to be anything significant at this time but there could be a few icy bridges. We’ll start focusing on Saturday Night’s potential tomorrow morning as we have our hands full as it is.