By Scott Martin - ​@RaceWx4You

Not a bad looking weekend out in Austin, Texas for this weekend's Trans Am Championship presented by Pirelli action at Circuit of the Americas. Warm temperatures can be expected throughout the event weekend, along with mild mornings, and dry conditions. A high pressure center will develop over northern Mexico, and this will allow for a southwesterly flow bringing in warmer air from south of the border. No rain is expected throughout the event weekend, but be sure to bring your hats, shades, and plenty of sunscreen. Highs will be in the 80s with early morning lows in the 60s. This would be nearly perfect weather for the summer, but pretty warm as highs will be nearly 10 degrees warmer than average for early November. Be sure to stay hydrated.

By Doug Schneider

A large high pressure system is expected to be the main weather feature throughout the 6 Hours of Shanghai weekend, which should provide nice weather conditions each day. The high pressure center starts out to the northwest of Shanghai on Friday, and as it builds in behind an exiting front, it will be breezy, with a north wind at 10 to 20 mph. The high shifts east through the weekend, and as it moves toward the Korean Peninsula and Japan, it will turn winds to the east. This will bring some moisture off the ocean - enough to increase cloud cover on Saturday and Sunday, but likely not enough to produce rain as the moisture should be shallow and confined to the low levels of the atmosphere. However, I'll be keeping an eye on this to see if it changes as we get closer to the weekend. 

By Doug Schneider - @Race4caster

It has become an annual tradition at Racecast Weather to share with you the best photos that combine our two favorite things - weather and race cars. Nothing compliments the beauty of race cars like a breath-taking weather scene in the background. So here's the collection for 2017 - click to enlarge. Hope you enjoy them.

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 Scott Martin - ​@RaceWx4You

As I mentioned in the first forecast for the event weekend out at Mazda Raceway Laguna Seca, an upper-level ridge would be moving into the area during the weekend bringing with it warmer temperatures. Model trends have come in stronger with the ridging and therefore temperatures will be allowed to rise several degrees above normal for mid-October, especially on Sunday. As for today, cooler weather will stick around before the ridge takes hold on Saturday. Unfortunately with the higher temperatures, the fire risk will continue to be high. Our thoughts and prayers go out to those who have been affected by the fires and to the ones who have lost loved ones. Radar will be up and running today as well... unfortunately, it will not be needed.

By Doug Schneider - @Race4caster

The outlook for the Six Hours of Fuji hasn't changed much in the past few days. It still looks like a very wet weekend as a front is expected to stall near the southern coastline of Japan. The one bright spot in this forecast update is that the impact of the rain on Saturday looks less than it did before. 

Today, radar shows that a solid line of showers will move across Fuji Speedway, associated with a cold front. As the front moves southeast, it will stall near the southern coast of Japan, just south of the track. Warm, moist air riding up and over the front will keep periods of rain going through Saturday and Sunday. The flow of moisture over the front appears to be weaker than it did a few days ago, so I have lowered the forecast rainfall amounts on Saturday, and dropped the Impact back to Moderate. This means that all planned on-track activity should be able to be completed, but probably not without some delays or at least the use of rain tires.

The pattern doesn't change much for Sunday, and periods of rain will continue to affect the racing action. Rainfall amounts look higher on Sunday than Saturday, with up to a half inch (13 mm) expected through the day. I think it will be a steady light to moderate rain, rather than a heavy rain that will cause the race to be stopped. Thus, I have the Impact as Moderate. With the surface front located to the south, temperatures will be cool all weekend.

By Scott Martin - ​@RaceWx4You

The forecast for racing at Mazda Raceway Laguna Seca looks great, but the overall forecast for the fire conditions continue to not look that good. Gusty winds and very low dewpoint values will unfortunately keep the risk of wildfires high. Our thoughts and prayers go out to those who have been affected, and to the crew battling the fires.

The forecast throughout the weekend can't really be any better for racing. Cooler temperatures will make it better for the drivers, but those same temperatures will warrant the need for jackets at multiple times throughout the event. The only concern that we may have is smoke from the nearby fires.

Friday will be a rather cool and quite breezy day, with winds starting out of the northeast and shifting out of the northwest at 5-15 MPH with gusts up to 20 MPH likely. According to how strong the system that will be moving into Nevada, we may have to increase those winds speeds.

Ridging will start to build in for Saturday and Sunday, bringing warmer daytime highs and lighter winds. Conditions will remain really dry throughout the weekend, and those jackets will be needed for the mornings. Highs on Saturday will be in the lower 70s, with upper 70s expected for Sunday.

Radar will be up and running starting on Friday morning, but it will not be needed.