By Doug Schneider

All eyes on are what will happen with Hurricane Kay and how it might impact the INDYCAR season finale at WeatherTech Raceway Laguna Seca. 

Hurricane Kay is forecast to track up the northwest coast of Mexico today and Friday, and weaken to a tropical storm. By Saturday night, it will be off the coast of San Diego, and start to curve toward the west. While the remnants of Kay won't have a direct impact on Monterey, it will have the effect of spreading moisture into the area. Whether there will be enough moisture to produce some rain at the track is uncertain, but it is at least a possibility, so I've added a small chance of rain to Sunday's forecast. I am confident that moisture from Kay will increase cloud cover on Saturday and Sunday, which will make for pleasant temperatures with highs in the mid 70s. 

By Doug Schneider

Hard to believe the INDYCAR season finale is already here. It's been a great season, and the finale should be very exciting with multiple drivers in contention for the championship. The weather should cooperate and not impact the race, but there are some uncertainties to the forecast that aren't shown in the graphic.

A large high pressure system will cover the western U.S. on Friday, and provide a sunny and warm day at the track. Meanwhile, Hurricane Kay will be tracking northward off the west coast of the Baja Peninsula. Below is the National Hurricane Center's forecast for Kay through Saturday. 

As you can see in the graphic, Kay is expected to take a northwesterly turn on Saturday, and it will likely stay well south and west of Monterey through Sunday. The main effect of Kay will be to increase clouds on Saturday and Sunday. I have seen some forecasts that have a chance of showers in the Monterey area on Sunday, based on Kay taking a track that stays closer to the California coast and spreading some moisture into the area. But I think it is more likely that the large high pressure ridge over the western U.S. will steer Kay away from the coast. So I can't completely rule out a shower on Sunday, but I think the chance is very low at this time. I'll have another update posted later this week before the event begins. 

By: Stephen McCoy

The weather pattern for this week over Portland is expected to be fairly stable, but with the possibility of a cold front approaching the region on Saturday. Dry conditions and minimal cloud cover will be present as a result. Some light fog may be possible during the early mornings, but will quickly clear as temperatures increase from morning lows in the 60's to highs in the 80s; temperatures may be slightly cooler on Saturday depending on the location of the front. The front may also bring a slight chance for isolated showers to the region Saturday morning, but will cause little to no impact to the track. Relatively light winds are expected throughout the weekend, shifting from the South/Southwest on Friday to the North/Northwest for Saturday and Sunday.

By Doug Schneider

Confidence is increasing that there will be some showers and thunderstorms to contend with for Saturday evening's Bommarito 500 at World Wide Technology Raceway. 

Friday looks nice - not much else to say about that. But during the day on Friday, a low pressure system will be dropping into the upper Midwest region. As that system tracks south and east through Saturday, it will bring showers and thunderstorms to the St. Louis area late in the day and the evening. As of today, I expect that the most likely time for these showers to arrive at WWTR is between 6 pm and 9 pm local time - during the race. An earlier or later arrival time, give or take a couple hours, is certainly possible, and keep in mind that a lot can change between now and Saturday. But that is my best estimate based on today's data. Hopefully the chance of rain will hold off long enough until the race is over. 

I'll have another update posted before the race to give a more exact timing estimate, and I'll be watching the radar and posting live updates on Twitter (@RacecastWx) during the race on Saturday. 

By Doug Schneider

A high pressure system will be over the Great Lakes region on Thursday and Friday, which should provide nice weather those days. However, an upper level trough will move into the northern Great Plains on Saturday. A southerly flow on the west side of the high pressure system will supply increasing moisture into the St. Louis area ahead of this trough. Showers and thunderstorms are expected to develop over Iowa and northern Missouri on Saturday afternoon, and track toward the southeast. There is a chance that they could arrive at WWTR during the race. Exact timing is still uncertain this far out, but I would put the chance of a shower or storm during the race at 40%. Check back for updates later in the week as the timing becomes more clear.

By Scott Martin.

Friday will be a steamy and humid day with partly to mostly cloudy skies. There will be a small chance for showers & storms during the morning, with storms becoming likely during the afternoon to early evening hours. Storms will be scattered in nature, so rain will not last all that long (if it does rain). 8 am temperature will be around 78º, with the afternoon high topping out around 88º. Winds will be out of the south to the south-southwest at 2-6 mph. Chance of rain will top out around 70%.

Saturday will feature partly to mostly sunny skies with a chance of a passing shower or storm, mainly during the afternoon to early evening hours. 8 am temperature will be around 78º, with the afternoon high topping out around 88º. Winds will be out of the south to the south-southwest at 2-7 mph. Chance of rain will top out around 40%.

Sunday will be very similar to Saturday... Partly sunny skies with a chance of a passing shower or storm, mainly during the afternoon to early evening hours. 8 am temperature will be around 78º, with the afternoon high topping out around 90º. Winds will be out of the south to the south-southwest at 2-7 mph. Chance of rain will top out around 40%.

By Doug Schneider

No major changes are needed to the forecast for the Gallagher Grand Prix. Friday and Saturday will have ideal conditions to spend the day at IMS. Temperatures will be seasonably cool, peaking in the lower 80s, and humidity levels will be comfortable. 

If you're going to the NASCAR race on Sunday, it will likely be another nice day, with highs in the lower 80s again.

By Doug Schneider

Ideal weather conditions are expected for the Gallagher Grand Prix at IMS. After a cold front passes through the area on Thursday night, high pressure will build over central Indiana and provide pleasant conditions. Temperatures will be cooler than normal both days, with highs in the lower 80s, and humidity levels will be quite comfortable. For late July in Indianapolis, you couldn't ask for better weather.