Heavy rain will drench San Antonio, but Hill Country is bracing for icy conditions

San Antonio – Heavy rains are imminent in San Antonio and much of our region. Thursday is on track to bring widespread drenching of much-needed rainfall.

The major upper low is still well west of Texas and will add dynamic lift to the atmosphere late Thursday evening into Thursday night as rain falls. Meanwhile, a surface low is developing south of Brownsville and will strengthen throughout the day Thursday as it moves north along the Texas coast. This low will work with the upper low to pump quite a bit of moisture into the state and our viewing area.

This coastal low will also pump enough “warm” Gulf air into our area to hold back most of the cold rain. The Hill Country will likely experience freezing temperatures for a period of time, allowing for some ice accumulation from freezing rain and possibly some sleet. A Winter Weather Advisory is in effect for the Hill Country to Val Verde County to address this potential. Be careful on bridges and overpasses when the advisory is in effect, especially if the thermometer in the car reads around 31 to 32 degrees.

Roads and bridges and elevated areas will only be wet in Bexar County and the rest of the region. In the morning it will rain sporadically and not across the board. Some sleet could also form briefly with the first showers as the atmosphere cools in response to the first showers. However, this would only be temporary.

During the afternoon and into the evening the dynamics above us will increase and rain will occur. Persistent moderate to at times heavy rain will spread throughout the area. The journey home will be ugly and very uncomfortable for people in their mid to mid 30s. The wind cools at times to around 20°C and the breeze is blowing.

The really good news in this forecast is the much needed rain we will be seeing! A heavy rain of 1 to 2 inches is likely, with rainfall totals just under 1 inch in areas closer to the Rio Grande.

All rain tapers off after midnight Friday and could end with a few snowflakes or sleet in the Hill Country as cold air tries to catch up with the trailing edge of the rain cover. The rest of Friday will be partly sunny to mostly cloudy and windy, in the 40s. There will be no refreezing issues for the Friday morning commute.