By Scott Martin - @RaceWx4You
Only slight adjustments to temperatures and wind to the forecast for Mazda Raceway forecast for the IMSA Continental Tire Monterey Grand Prix. Highs are coming in a little cooler, so you may need to hang on to those jackets a little longer during the day.
By Doug Schneider - @Race4caster
It will be a great weekend to head to beautiful Virginia International Raceway to take in some awesome race cars. Trans Am will have a shared weekend with SVRA's Heacock Classic Gold Cup Historic Races, and the schedule is jam packed with action. A large area of high pressure will be stationary over the Great Lakes and Mid Atlantic region, and it will keep dry and sunny weather across Virginia later this week. Temperatures will be pretty warm too under the high pressure ridge, between 4 and 8 degrees above normal for late September in southern Virginia. There's good agreement among the models on this pattern, so I don't expect that there will be many changes needed to this forecast through the week. Check our social media feeds on the right for updates.
Click on images to enlarge.
By Doug Schneider - @Race4caster
The main weather story for the Six Hours of COTA late this week will be the heat. A large high pressure ridge through the mid and upper levels of the atmosphere will be sitting over Texas, resulting in mostly sunny skies each day and high temperatures reaching well into the 90s (mid 30s C). These temperatures are 3-5 degrees warmer than normal for Austin this time of year. Everyone at the track will need to take precautions to beat the heat - drink plenty of water, take frequent breaks in the shade or in a air conditioned building, and use sunscreen.
It's a championship-quality forecast for the final weekend of the season for the Verizon Indycar Series, as they visit the majestic Sonoma Raceway. Mornings will start off cool each day, but maximum sunshine will allow the temperatures to climb nicely to near 80 degrees each day. Wind will not be an issue for Friday and Saturday, but will be picking up to 10 MPH by Sunday afternoon. We won't even mention rain in this forecast.
By Doug Schneider - @Race4caster
The SVRA and Trans Am event at Watkins Glen will start off with some wet weather, but conditions will be improving over the weekend.
There will be a large upper level trough across the area on Thursday and Friday, which will produce cloudy and cool weather with scattered showers. Thunderstorms do not appear to be a threat at the track, and at this time I do not expect that the rain on Friday will be very heavy. It looks like there will be mainly light showers that are on and off at times through the day, perhaps occurring with more frequency in the afternoon than the morning.
The chance of rain will continue Friday night, but I expect that the trough will be moving fast enough that the chance of rain will end before the TA2 race on Saturday morning at 10:55 am. This is one part of the forecast that I'm not very confident about right now - it is possible that a few showers could linger into Saturday morning, but I'm going with a dry day for now because I don't think it will have an impact while there is action on the track. Clouds will be decreasing through the day, with mostly sunny skies developing in the afternoon. Despite the sunshine, a north wind will keep temperatures cool, with highs in the mid 60s.
Sunday looks great as a strong high pressure ridge builds into the area. While morning temperatures will be quite cool, in the 40s, sunny skies will bring temperatures up to the upper 60s in the afternoon.
For much of the week I thought that the remnants of Harvey would be swept out of here before the race weekend at Watkins Glen for the Verizon Indycar Series, but the forecast has changed drastically today.
Saturday will not be too bad at the track with partly cloudy skies throughout much of the day. Morning temperatures will start off pretty chilly and may bring a slight delay to morning on-track activities, but it will warm quickly into the mid 60s for the high. There is a very slight chance of a shower passing over the track after the noon hour, but the better rain chance will come during the late afternoon and early evening hours.
Sunday will be a pretty soggy day for the track, especially during the morning and into the early afternoon hours. It will be quite breezy at times as well, as the surface low formerly known as Harvey, passes nearby to the track. We do not expect any severe weather or lightning at this time, but definitely keep posted to the weather conditions through the day. Rain coverage should diminish for the mid-afternoon through the early evening hours, and maybe we can get a dry track for a little while. Afternoon highs will top out in the upper 60s.
By Doug Schneider - @Race4caster
There hasn't been a big change in what I'm thinking the weather will be in Mexico City this weekend for the WEC event, but my confidence is rising that the racing will be impacted by rain each day. A low pressure system will be taking shape in the Gulf of Mexico, just off the east coast of Mexico. This will produce an easterly flow through the low and mid levels of the atmosphere that will pump moisture toward the track all weekend, but especially Saturday and Sunday. With mountains all around the city, the moisture rising up the mountains slopes will produce showers and thunderstorms each day, and mainly in the afternoon hours. I've raised the chance of rain with the forecast update to reflect my higher confidence, and I've raised the Impact to High, as I think there's a good chance of the rain being heavy enough at times to require a stoppage in the action. Rain amounts are likely to be between a quarter and a half inch each day, but amounts could be higher than that if a storm moves directly over the track.
The Weather Channel has a pretty good interactive radar display for Mexico here -
The remnants of Hurricane Harvey will be pulling out of Texas by Thursday, and high pressure will build over the state behind it. The high pressure system will bring drier and and stable conditions. This should provide nice weather for Pirelli World Challenge at COTA this weekend. Temperatures will be close to normal for Austin this time of year, with highs in the lower 90s and lows around 70. With a lot of sunshine each day and very little shade at the track, it will be important to stay hydrated and to use sunscreen.
As the high pressure system over the Plains shifts to the east near the Mississippi River on Sunday, winds near and just above the surface will shift to a more easterly direction. This will transport a little more moisture inland on Sunday, which is why I have a slight chance of showers and thunderstorms in the forecast. I think that most of the activity will stay closer to the Texas coast, well east of COTA, but there is some uncertainty about how far inland storms may develop this far out in the forecast. There is just a very low chance that the racing could be impacted by storms. I'll be keeping an eye on this through the week, so check back here for updates and follow me on Twitter - @Race4caster.
It looks like the WEC weekend in Mexico City could be a wet one, as there's a good chance of showers and thunderstorms each day at the track. The weather pattern doesn't change very much through the weekend, as there will be a good amount of moisture in the atmosphere. There may be a slightly better chance of rain on Saturday as a low pressure system in the midlevels of the atmosphere develops, producing an stronger easterly flow of moist air off the Gulf of Mexico. But for the most part, the showers and storms will be driven by afternoon instability. It is possible that a heavy shower could stop racing action, but rain amounts are too uncertain this far out to put the Impact rating any higher than Moderate.
I'll keep an eye on how the models change as we get closer to the event, and I'll post an update when any changes are needed.
Not much change in the forecast for the Bommarito Automotive Group 500 at Gateway Motorsports Park...
Great weather throughout the afternoon hours, with mostly sunny skies and highs in the lower 80s. That is how it will be for the first practice session at 4PM. Qualifying temperatures will be down in the mid to upper 70s, and final practice temperatures at 9PM will be in the lower 70s and dropping into the upper 60s by the end of the session.
Almost a near repeat of Friday's weather... Sunny skies throughout the day with temperatures topping out in the lower 80s. Temperatures will be dropping down into the mid 70s by the start of the main event at 8PM, and down into the lower 70s by the end of the race around the 10PM hour.
Well a lot has changed since my last forecast for this weekend's events at Road America for the Trans Am Series Presented By Pirelli. We now will have a chance of showers and thunderstorms to end out the race weekend.
Definitely the best day of the event weekend when talking about the weather. We'll have sunny skies throughout the day today with cool temperatures for late August. Afternoon highs will warm up in the upper 60s after temperatures will be starting off at 50 degrees at 7:00AM. No rain for today, and winds will start off out of the north at 5-10 MPH and shift out of the east by the early afternoon hours.
There will be a warm front approaching from the west during the day that will bring an increase of clouds to the area, along with slightly warmer temperatures. It will still be rather cool at 7:00 AM with temperatures starting off in the lower 50s, but afternoon highs will make it to near 70 degrees. Winds will be out of the east at 5-10 MPH to start with, but will shift out of the southeast by the afternoon hours. With the shift in the wind direction, this could bring an isolated shower or two to the area, but with a dry airmass at the surface, you may not see much rain at all. Rain chance will only be at 20% for the late afternoon hours.
The warm front will have moved through the area and a center of low pressure will be approaching the state from the west. Along with that, an upper level trough will move into the state from the north allowing that low to deepen. This will increase the chance of showers and thunderstorms throughout the day, especially the early morning through the early afternoon hours. Skies will be cloudy throughout the day, and afternoon highs will be in the upper 60s. The best chance of rain will be during the 1:00 AM - 11:00 AM time frame, with scattered showers possible after that. The chance of rain during event times will be at 50%.
By Doug Schneider
Virginia International Raceway is about a five hour drive from my house, but it's the track I consider my "home track". If you've never been there, it is a gorgeous facility with a ton of great viewing spots, and you should definitely put it on your list of tracks to visit. I will be at the track this weekend, so I'm very pleased that I can make a forecast that calls for beautiful weather each day.
A cold front is expected to move through the area on Wednesday night, which will bring some storms. Behind it, a large area of high pressure at the surface will be tracking across the Great Lakes and into New England through the weekend, and extend southward along the east coast. In the upper levels of the atmosphere, there will be a trough located near the coastline, producing a northwesterly flow aloft. The upshot of these features will be dry weather with plenty of sunshine, temperatures cooler than normal, and comfortable humidity levels.
There is one caveat to this forecast that I have to mention. One model (the GFS) does produce some afternoon showers each day, mostly near the mountains to the west, but it does show some precipitation reaching the track. My experience with this model is that it sometimes overplays the chance of afternoon showers in the summertime. Other models and the forecast from the NWS favor a dry weekend. At this time, I'm going with a dry forecast, expecting that this wetter model will change as we get closer to the weekend.
Not much change has been needed to the forecast I made on Monday, as I'm still expecting nice weather for the ABC Supply 500 on Sunday.
A cold front will move across the area on Friday, which will bring a good chance of storms that day. More stable air will build in at the surface behind the front, but an upper level trough will lag behind it and keep a slight chance of showers going into Saturday. There is a possibility of some isolated light showers around the track for the final practice session late in the day, but the showers should be so sparse and short-lived that I don't expect much, if any, impact. I think the timing of possible showers favors the late afternoon and evening hours, mainly 4 pm or later.
The models differ on how fast the trough will exit, and there may continue to be some showers into Saturday night. But I'm confident that any chance of showers will be gone by sunrise. Race day will be mostly sunny with pleasant temperatures in the upper 70s, and a northwest wind at 5 to 10 mph. Overall, a great day to be at the track.
Overall, the forecast looks favorable for a nice weekend of IndyCar racing at Pocono Speedway. Hopefully this forecast will hold up as we get closer to the weekend.
There will be a good chance of showers and thunderstorms in the area on Friday, and a cold front is expected move through on Friday night. The upper level trough is delayed a little behind the front, which is why I've included a slight chance of showers on Saturday. A dry day is most likely, but I can't entirely rule out an isolated shower until the trough exits the area on Saturday night.
As the trough exits, dry air aloft will build into the region from the northwest, along with surface high pressure. This should provide a nice day for the race on Sunday. There should be a good amount of sunshine, and temperatures will be pretty comfortable too, with highs in the mid 70s.
Unless there's a major shift in the forecast, I should have another update posted on Wednesday afternoon.
Only a slight change in the forecast for this week out in Tooele, Utah, as the Pirelli World Challenge Series visits the grand Utah Motorsports Campus. Throughout the entire weekend you can expect mostly sunny skies, and I removed the risk of an isolated shower or thunderstorm on Sunday. Highs will be in the lower 90s degrees. Winds will shift on Friday and Saturday during the late morning hours, but are expected to stay out of the southeast at 5-10 MPH on Sunday.
Since rain is not expected, radar will not be utilized for this event. I'll continue to have updates throughout the rest of the week and weekend here on the website and on my Twitter feed @RaceWx4You.
The forecast for Mid-Ohio is coming into better focus today, and the good news is that race day for the Trans Am Series is looking pretty nice. But there could be some rain before that.
Today will begin mostly sunny, but clouds will increase in the late morning and early afternoon. Showers and thunderstorms are expected to develop across central and eastern Ohio as moisture spreads up from the south, but the coverage of showers should be scattered. The chance of rain at the track today is around 30%, and any showers that may occur should be brief, so there should be plenty of dry track time for practice sessions.
The chance of rain rises on Friday as there will be a cold front approaching from the west that will result in greater coverage of showers and storms in the afternoon. Expect the timing of storms on Friday to be 2 pm or later, so the qualifying sessions could be impacted. If a storm occurs at the track, it could produce a quick quarter of an inch of rain, in addition to cloud-to-ground lightning. Those at the track will need to stay weather-aware and take shelter when thunder is heard.
The front is expected to move through Friday night, and drier air will build in behind it. This should give a nice day for racing on Saturday, with partly cloudy skies and highs in the upper 70s.
This is really a plain and simple forecast for this week out in Tooele, Utah, as the Pirelli World Challenge Series visits the grand Utah Motorsports Campus. Throughout the entire weekend you can expect mostly sunny skies, with the exception of a very small risk of an isolated shower or thunderstorm on Sunday. Highs will be in the upper 80s to just at 90 degrees. Winds will start out of the southeast on each day at 5-10 MPH, but will shift by the afternoon hours. The only thing that I would recommend is to stay hydrated and keep the shades and sunscreen handy.
There's a fair amount of uncertainty in the forecast for Mid-Ohio late this week, so the finer details are hazy, but the general pattern appears to be a bit unsettled. This will result in some chance of rain each day for the Trans Am event Thursday through Saturday. But it will not be a washout by any means.
Thursday is expected to have some showers and thunderstorms in the area that develop in the afternoon. Most of the day should be mostly sunny and dry, with comfortable temperatures around 80 degrees.
On Friday there will be a low pressure system tracking east across the upper Great Lakes, so there will probably be increasing moisture over Ohio. An upper level disturbance may also be crossing the area, so I think the chance of rain on Friday is probably the highest of any day of the event. But coverage is expected to be scattered, so there will still be plenty of opportunity for dry racing.
On Saturday there may be some dry air building into the area behind the exiting upper level disturbance, but the models don't completely agree on this. While I think a dry day is most likely, I will have to keep a small chance of rain in the forecast as it can't be ruled out completely at this point.
Sunday will be a mostly cloudy with the possibility of a few showers or storms passing through the area during the day, but mainly in the afternoon hours. There will be a little instability already in the area, along energy associated with a shortwave moving through, that will allow for the development of convective showers and thunderstorms. I've included a couple of forecast maps from the National Weather Service Weather Prediction Center.
Good news is that environmental conditions will not be favorable for severe storms, but some of these showers could put down a good bit of rain in a short amount of time. I do not believe flooding will be an issue, but cloud-to-ground lightning could be. Remember the rule... "When thunder roars, go indoors!"
Winds will start off out of the west at 5-10 MPH, but will shift out of the southeast by the late morning hours. The afternoon high will be in the mid 70s, and the chance of rain at the track is at 40%. In case you would like to know what does a chance of rain actually means, then click here to read a post that Doug put up a few years back.
As always, radar is running on our site, and I'll have updates throughout the afternoon on Twitter at @RaceWx4you.
By Doug Schneider
Showers are moving across Ohio today ahead of an approaching surface low pressure system and a cold front. The surface low and front will be southeast of the area by Friday morning, but the upper level trough will lag behind. This is what will keep a chance of showers going at Mid-Ohio on Friday.
I am keeping the chance of rain at 40% today because I do not believe that the entire day will be a washout. There should still be plenty of on-track activity, so I have the Impact Forecast at Low. The most likely time period for rain at the track appears to be in the late morning to early afternoon hours, mainly between 10 am and 3 pm. Looking at the event schedule, the rain may affect IndyCar practice, PWC practice, USF2000 Race 1, and Indy Lights qualifying. But it won't be raining through all those activities - I expect scattered coverage of on/off showers. Thunderstorms are possible, but they should be few and far between. Rain amounts are most likely to be around a tenth of an inch, but up to a quarter inch may be possible if a thunderstorm happens to directly cross over the track.
Behind the exiting trough, high pressure will be building across the Great Lakes region on Saturday. A brisk northerly flow will keep temperatures relatively cool all day, with highs in the mid 70s. A north wind will be blowing between 10 and 20 mph, with gusts to near 25 mph at times, so pin down your tents and lawn chairs.
Sunday looks absolutely perfect for racing - highs in the upper 70s with plenty of sunshine. North winds will be a little lighter on Sunday, between 10 and 15 mph.
I'm putting out an update earlier than planned today because the models have shifted the chance of rain into Friday for Mid-Ohio today. The cold front that will bring numerous showers and thunderstorms on Thursday is still expected to move across the area on Thursday night, but the upper level trough will lag behind it, and keep a chance of showers into Friday. With the models showing the upper trough over Ohio on Friday, this will create some instability that will generate scattered showers. The showers could affect the track at any time of the day. At this time, the showers should be light, with perhaps at tenth of an inch of rain expected.
The rest of the weekend still looks great, with pleasant temperatures in the 70s and lots of sunshine. Saturday will be breezy behind the departing low pressure system, with gusts around 20 mph at times.
The weather looks great at Mid-Ohio this weekend for IndyCar, MRTI, and Pirelli World Challenge racing. While the practice day on Thursday will likely have showers and storms, the rest of the event is expected to stay dry with comfortable temperatures and humidity levels.
A cold front will be approaching Ohio from the northwest on Thursday, There is some uncertainty about the timing details of the storms ahead of the front, so at this point I can't be too specific about it, and there could be showers at any time of the day. The cold front will move through Thursday night, and all the rain will be out of the area by the time cars hit the track on Friday morning.
Behind the cold front, high pressure will settle into the Great Lakes region while a low pressure system will be east of the Appalachians, and this pattern will remain nearly stationary through the weekend. This will provide a north to northeasterly flow across Ohio that will keep temperatures and humidity levels very comfortable. High temperatures each day will be between 75 and 80, with low temperatures around 60. There will be a steady northeast breeze of 10 to 15 mph each day.
Unless there is a major change in what the models are showing, which I doubt, my next forecast update will likely be posted on Wednesday.
Not much has changed in my thinking for the forecast for Nurburgring this weekend, but some of the finer details are coming into better focus.
The chance of rain in Friday is expected to be mainly in the late afternoon, probably moving into the area between 3 and 5 pm, with the bulk of it falling between 5 and 7 pm CEST. Rain amounts do not look particularly heavy, perhaps around a tenth of an inch, or between 2 and 3 mm.
Saturday will have cloudy skies but the rain will be well east of the area by then. With very little sunshine, high temperatures will only be in the upper 60s or lower 20s C.
Sunday looks like a very nice day, with partly cloudy skies and temperatures warming into the upper 70s (mid 20s C). The slight chance of rain that I had in the previous forecast is gone, as that chance of rain will hold off until Monday.
The opening day of on track action at Nurburgring will likely have some rain. A cold front will be moving across the area in the morning, but a high chance of rain will continue through the day as the upper level trough moves through. There is pretty good model agreement on this general pattern, so I have a high chance of rain at 70%. Rain amounts at this time appear to be between 0.15 and 0.3 inches, or between 4 and 8 mm.
The upper level trough will be east of the area by Saturday, and a weak ridge will build over the area, so I think it will be a dry day with a mix of sun and clouds.
Sunday is probably the biggest question mark in the forecast. The ridge will be weakening through the day, and a weak upper level disturbance is expected to be crossing England and the Netherlands. With weak features like this, the models usually have a harder time figuring out their location and timing. I don't have a lot of confidence on Sunday's forecast, so I have just a slight chance of rain forecast for now with low impact on the race. We'll see how this evolves over the next few days, so check back for updates and follow @Race4caster on Twitter.
Doug Schneider and Scott Martin are race fans and meteorologists dedicated to providing accurate forecasts and timely weather updates at racing venues around the world. We forecast for IndyCar, Indy Lights/MRTI, IMSA, Pirelli World Challenge, World Endurance Championship, and Trans Am Series races, as well as major SCCA and NASA events.