Spring, Texas – December 28th, 2017 (National Weather Service): Much colder air now over Canada will reach the region on Sunday, allowing for temperatures to fall below freezing by Monday morning for areas north of I-10. Light rain will be possible during the day ahead of the front Sunday and may linger long enough behind the front Sunday night into early Monday morning to produce light freezing rain or drizzle across areas north of a Brenham to Cleveland line. Forecast confidence is low with respect to the occurrence of freezing rain/drizzle on Sunday night. However, any water still on roadways when temperatures fall below freezing Sunday night may result in slick or icy spots.
Forecast confidence is highest with respect to temperatures. Widespread below freezing temperatures will be possible Monday morning north of I-10 and all the way to the coast on Tuesday morning. Wind chills during this time may drop into the teens and Wind Chill Advisories may be needed. These cold temperatures may be of particular concern for individuals displaced or affected from Harvey and utilizing temporary or makeshift housing.
The National Weather Service says they are highly confident that sub-freezing temperatures and low wind chills will affect parts of the region next week and this appears to be the primary weather hazard going forward. They have low confidence on when, where, or what locations may be impacted by winter weather. Depending on how quickly the cold front moves through, winter weather may not occur at all Sunday night or may be delayed until the middle of the week as an upper-level system arrives. As more data becomes available, refinements to this forecast are likely.