By Scott Martin - ​@RaceWx4You

Forecast is still pretty similar from what I first put up earlier this week. Just made adjustments to the rain chances for each day. Stay weather aware as lightning may be an issue with storms. When thunder roars, go indoors. Good news is that rain will come to an end before noon on Sunday. If that happens, track may dry out and the slicks can be put to use. Radar is up and running.

By Scott Martin - ​@RaceWx4You

Looking at the latest forecast models for the Austin area throughout the weekend show that an approaching trough with an associated cold front will be making its way toward the area on Friday and Saturday. With that, along with high pressure and ridging to the east, this is allowing warm and moist gulf air to flow in from the southeast. Skies will be mostly cloudy, and as the trough gets closer, we will have a chance of isolated showers and thunderstorms on Friday and during the day on Saturday. Highs on both of these days will be in the lower 80s (27-28ºC). Winds will be out of the east-southeast around 5 MPH (8 KPH) on Friday, and out of the south at  5-10 MPH (8-16 KPH) on Saturday.

The trough arrives with the cold front on Saturday evening and will work its way through during the first half of Sunday. This will bring a decent chance of showers and thunderstorms for Saturday night through a good part of the daytime hours on Sunday. Unfortunately, rain chances at this time doesn’t appear to drop off until after 5:00 PM (2200 UTC). Winds will be quite breezy and cool as they will shift from the west to out of the north by the afternoon hours, averaging between 5-15 MPH (8-24 KPH) with gusts up to 20 MPH (32 KPH) possible. Rainfall amounts of 1/2 inch to 3/4 inch (12.7mm-19mm) are possible, and rain tires are almost a sure bet. Afternoon highs will be much cooler only reaching the upper 70s (24-25ºC).

Lightning may be an issue with any rain throughout the weekend, so please seek shelter if you hear thunder. The saying is “if you hear thunder, you are close enough to be struck by lightning.” So when thunder roars, go indoors. Radar will be up and running on our website starting on Friday and will be up throughout the weekend. Please feel free to share any of this information with friends or relatives that are headed out to COTA for the event.

By Doug Schneider

Scott and I both have a passion for weather and motorsports that began in childhood. We started forecasting weather for open wheel and sports car races a year ago as a means of combining two of our favorite things. We're excited that we can be a help to fans, teams, and race officials by doing what we love through Racecast Weather. I also love weather photography and racing photography, so here's a collection of some of my favorite photos that combine the two.

Credit for these photos goes to David Yowe (dlymotorsportimages.com), John Dagys and the photographers at Sportscar365, John Thawley (johnthawley.com), and the F1 Fanatic photo collection (f1fanatic.co.uk)