By Doug Schneider - @Race4caster

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. 

By Doug Schneider - @Race4caster

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.

​By Scott Martin - ​@RaceWx4You

Not really much change for the Grand Prix of Utah for the Pirelli World Challenge at Utah Motorsports Campus. Hot with a mix of sun and clouds for both Saturday and Sunday, with a very slight risk of an isolated shower or thunderstorm. Highs will be in the lower 90s.

By Scott Martin - ​@RaceWx4You

By Doug Schneider - @Race4caster

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.

By Scott Martin - ​@RaceWx4You

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.

By Doug Schneider - @Race4caster

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. 

By Scott Martin - ​@RaceWx4You

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 Scott Martin - ​@RaceWx4You

By Scott Martin - ​@RaceWx4You

Skies will continue to be mostly cloudy throughout the day on Friday, and there is a decent chance of scattered showers and thunderstorms throughout the day, but those chances will begin to diminish during the afternoon hours. We'll start off in the upper 50s, and top out in the mid 60s for the high. Winds will be quite gusty out of the northwest at 15-20 MPH, with gusts up to 30 MPH.

Saturday will be the best day weather-wise at Road America, with mostly sunny skies, and only a very small risk of an isolated afternoon shower or storm. Saturday will also be the warmest day of the event with the high hitting the mid 70s, after starting off in the mid 50s when the gates open. Winds will be out of the west at 5-10 MPH.

Sunday will have a chance of showers and thunderstorms at Road America throughout the day. Skies will be mostly cloudy otherwise, and the high will top out in the lower 70s. Winds will be starting out of the west at 5-10 MPH, but will be shifting out of the southeast by the late morning.

Have an umbrella handy and pay attention to the PA announcer. Road America does a great job in alerting fans and teams of inclement weather. But don't let that deter you from attending the great racing action. Rain only makes the best drivers in the world shine, and you'll have an opportunity to see that happen. Radar will be up and running by Friday morning.

By Scott Martin - ​@RaceWx4You

After spending a week at the beach with the family, I am back with your forecast for the IMSA Continental Road Race Showcase at Road America. For those who like to see racing in the rain, you will probably be happy at some point during the event weekend.

Thursday looks to be the wettest of the day during the event, with showers and thunderstorms likely during the afternoon and early evening hours. After starting off in the lower 60s when the gates open, the afternoon highs is expected to climb into the lower 70s. Winds will be out of the east at 5-10 MPH.

Skies will continue to be mostly cloudy throughout the day on Friday, and there is a decent chance of scattered showers and thunderstorms throughout the day, but more likely during the afternoon hours. We'll start off in the upper 50s, and top out in the mid 60s for the high. Winds will be out of the northwest at 10-15 MPH.

Saturday will be the best day weather-wise at Road America, with mostly sunny skies, and only a slight risk of scattered afternoon showers and storms. This will be the warmest day of the event with the high hitting the mid 70s, after starting off in the mid 50s when the gates open. Winds will be out of the west at 5-10 MPH.

Sunday a decent chance of showers and thunderstorms return to Road America throughout the day, but the better chances will once again be in the afternoon. Skies will be mostly cloudy otherwise, and the high will top out in the lower 70s. Winds will be out of the west at 5-10 MPH.

If you're at the track, please remember that if you hear thunder, you are close enough to be struck by lightning. When thunder roars, go indoors!. Have an umbrella handy and pay attention to the PA announcer. Road America does a great job in alerting fans and teams of inclement weather. But don't let that deter you from attending the great racing action. Rain only makes the best drivers in the world shine, and you'll have an opportunity to see that happen.

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. 

By Doug Schneider - @Race4caster

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.

By Doug Schneider - @Race4caster

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. 

By Scott Martin - ​@RaceWx4You

You know what... I think we may have mostly dry conditions throughout much of the morning and the early afternoon hours at Exhibition Place in Toronto for race day for the Honda Indy Toronto. Both of the trusty forecast models that I use for short range outlooks are in very close agreement on timing with an approaching front that will be bringing showers to the area.

The good news is that it would appear that the best chances of showers and a possible thunderstorm would be likely starting after the 3PM EST and last through the remainder of the late afternoon and into the evening hours. There will be rain that should be moving by to the north of the event during the morning hours that could bring a light shower, but that shouldn't last very long at all and only be an inconvenience for a few minutes.

When, and if, the rain starts falling during the late afternoon, amounts will be around 1/4 inch or less, so I do not think it will be a washout, and I don't think the rainfall will be intense enough to bring out a red flag during the race. There will be enough to warrant the use of the gray sidewall Firestone Racing rain tires. Afternoon high will be around 81 degrees, and winds will be out of the southwest at 5-15 MPH. 60% chance for rain after 3:00 PM.

Unfortunately, the closest NWS Radar site in Buffalo, NY, has had a major equipment failure, so the software that we use for our site will be unable to do radar. Therefore, I will have updates throughout the afternoon on my Twitter feed @RaceWx4You using RadarScope.

By Scott Martin - ​@RaceWx4You

I am having to apologize for not putting up a discussion until today for this week's Verizon Indycar Series event in Toronto. Active weather in Alabama has once again kept me pretty busy. Here is the forecast for The Honda Indy Toronto.

Friday looks to be a pretty OK days in Toronto. The trusty forecast models that I am using are in pretty close agreement that rain should not be a factor throughout much of the day at Exhibition Center. I can't entirely rule out a stray shower or two moving through in the afternoon hours, but the risk is rather low at this point. The Canadian weather bureau has a 40% chance of showers and storms, I'm thinking that it will be less than that (about 20%), especially during track activity times. So I'll say mostly cloudy skies with a small risk of an afternoon shower or storm. Afternoon high will be in the lower 70s.

On Saturday, weather will not be an issue at all. It will be a mainly sunny day in Toronto, and quite warm as well. Afternoon high will be up in the lower 80s. Only concern will be getting sunburn. Be sure to pack the shades, hats, and sunscreen.

Sunday is going to be an interesting day at Exhibition Place. Some of the race fans who follow us have been complaining about not having a wet race. Well, there is a decent chance that rain tires will be needed for The Honda Indy Toronto. Both the GFS and NAM-12k are in agreement about a line of rain pushing through at some point during the late morning through the early afternoon hours. Considering that one is showing that the line will be sort of broken in nature, that will keep the chances a little lower in my eyes. With that being said, it will be a cloudy day with a decent risk for showers during the late morning throughout the afternoon hours. The afternoon high will be back down into the mid 70s. I'm pretty close in my thinking for rain chances with the Canadian weather bureau... I'm going 50%, they are going 60%. Either way, if it rains, we're both correct.

I will have radar up and running, but since the race is in Canada, the closest radar is located in Buffalo, I may not have the best geographical information. I am searching for the latest place files for our radar software, so hopefully I can find some that will suffice.

By Doug Schneider - @Race4caster

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.

By Doug Schneider - @Race4caster

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. 

By Doug Schneider - @Race4caster

Here's a look at the radar and surface observations across Ontario this morning:

CTMP is located at the red dot northeast of Toronto. I've drawn the approximate position of a cold front with the blue line. There are showers across Michigan and Lake Huron this morning, but I'm not too concerned with these affecting the track - the storms in Michgan will pass south, and the shower over Lake Huron is dissipating. I do expect that as the cold front tracks into southern Ontario late this morning, additional showers and thunderstorms will develop. I expect that there will be scattered storms in the area around CTMP between 2 pm and 6 pm. The chance of one of them hitting the track is about 50%. I have lowered the chance of rain from the previous forecast, as the coverage of showers does not look as great as it did a couple days ago. The Prototype Challenge and WeatherTech practice sessions are the ones most likely to be affected. Rain amounts around a tenth of an inch can be expected if a shower or storm hits the track, with an additional tenth of an inch possible tonight.

The cold front will move through the area tonight, and I expect the rain to exit with it. In the previous forecast, there was a small chance of a shower lingering into Saturday morning as the upper level trough moved through, but the timing of that looks faster today, so I've removed that small rain chance from Saturday morning. It should be a really nice day to be at the track, with cool temperatures in the 70s, low humidity, and a breezy northwest wind.

Unfortunately, Sunday is moving in a wetter direction. Another cold front will be approaching the area, and since it looks to arrive sooner than previously projected by the models, I've had to raise the chance of rain. The 30% chance of rain in the forecast graphic is the chance of rain during the race, which will be held between 12:05 pm and 2:45 pm. There is a higher chance of rain after the race ends. I expect that any rain that might fall during the race will be light, so I have the impact ranked as Low. It could just be some sprinkles that barely even wet the track, like we saw at the end of the Watkins Glen race. Heavier rain may arrive in the late afternoon or evening hours. 

By Doug Schneider - @Race4caster

My confidence in how the weather will play out at CTMP this weekend is increasing in some ways, but decreasing in others. It still looks like Friday's practice sessions will be affected by rain and thunderstorms, but there should be little to no weather impact on the racing action on Saturday and Sunday.

The models continue to point toward Friday for the best chances of rain as a cold front will be approaching the area. Numerous showers and thunderstorms will move through southern Ontario with the front during the day, and rain amounts are expected to be between a quarter and a half inch. This could cause some of the sessions to be canceled, so I've ranked the impact at Moderate. But that will depend on the finer details of timing of storms, which is still uncertain.

The cold front will move east of the area Friday night, but a trough in the midlevels of the atmosphere will lag behind. There will still be a chance of showers until that trough moves away, which will happen on Saturday. I think it will just be a slight chance of rain, mainly Saturday morning, and any rain will be light. By the afternoon, clouds will be decreasing and sunshine will be increasing, although it will be breezy with a northwest wind between 10 and 20 mph. The northwest wind will usher cooler temperatures into the area, and highs will be in the mid 70s. 

Sunday is becoming more of a question mark, as the models have changed their tune a bit about the pattern. One model (ECMWF) brings a second cold front and upper level trough into Ontario on Sunday, and it shows rain in the area Sunday afternoon. Another model (GFS) shows a much weaker trough and a front that stays north of the track. I've added a mention of an isolated late day shower to Sunday to account for the possibility, but I'd only put the chance of rain at 10% right now. I don't have enough confidence make a big change to Sunday's forecast at this point, since a dry day seems most likely. Hopefully that won't change as we get closer to the weekend, but stay tuned.

By Doug Schneider  - @Race4caster

The IMSA teams don't get much of a break this week after Watkins Glen, and neither do I. While there is a good chance of seeing rain this weekend at CTMP, I expect that the impact on racing will be low. 

Friday's practice sessions have the best chance of seeing wet conditions. An upper level trough and a surface cold front will be approaching the area from the northwest, and with a little daytime heating, showers and thunderstorms should develop across much of Ontario during the day. The afternoon is probably going to have higher rain chances than the morning due to more instability, but timing is still too uncertain this far out to be confident about that. 

The cold front is expected to move across southern Ontario on Friday night, taking the bulk of the rain with it, and the models are in pretty good agreement about that. However, they differ on how fast the upper level trough moves through, and so I don't have a lot of confidence about what will happen on Saturday. I have a slight chance of rain mentioned on Saturday to account for the possibility of the slower scenario. Even if there is rain on Saturday, it will most likely be light and have little impact on the racing. It is possible that the trough could move through faster, taking the rain away on Friday night, and Saturday could stay dry. In either case, it does look like cooler temperatures will build in behind the front for Saturday, with highs in the mid 70s (lower 20s C). It will be a little breezy too, with a north wind at 10-15 mph. 

Sunday looks like a great day for racing. The models agree on high pressure building over the Great Lakes, and a dry north to northwest flow providing dry air aloft. I expect mostly sunny skies and highs in the upper 70s (mid 20s C). 

Follow along on all our social media feeds on the right sidebar to keep up with changes in the forecast through the week.

By Doug Schneider - @Race4caster

Today's weather at Watkins Glen will be much improved compared to yesterday, but there's still a small chance of a shower in the afternoon. The odds favor a dry race, but I can't rule out the possibility of a shower toward the end of the race.

Fog has been observed around the area, with visibility at the Elmira airport at a quarter mile at 6 am. Any fog at the track will be in the process of lifting around 8 am when the morning warm up session starts. If the fog is thick enough, it could delay the session. At the start of the race, it will be mostly sunny with a light southwest wind. Temperatures will warm to around 80 degrees by 2 pm. 

A broad upper level trough will be over the region today, and it will create just enough instability to spark some showers in the Finger Lakes region this afternoon. This is a simulation of what one model (HRRR) thinks the radar could look like this afternoon, from noon to 5 pm:

Sometimes this model develops too many showers in this type of situation, so I think the coverage of showers will be a little more sparse than what it is showing. I'd put the chance of a shower hitting the track today at about 20%, with the timing of possible showers between 2 pm and 5 pm. 

By Doug Schneider - @Race4caster

On and off rain showers will continue across the Finger Lakes region through the morning hours. Here's a look at the big picture radar (WGI is the red dot):

There is still quite a bit of rain across western Pennsylvania moving northeast that will affect Watkins Glen today. I expect that the main area of rain and thunderstorms will occur at the track between 8 am and noon. Around a quarter inch of rain is likely, and possibly up to a half inch. This could potentially impact Prototype Challenge Race 2, Porsche GT3 Cup Race 2, and WeatherTech qualifying.

There is also a Slight Risk of severe thunderstorms in the area. Here's the graphic from the Storm Prediction Center: 

Watkins Glen is on the western edge of the Slight Risk area. While there is a potential for storms to produce strong wind gusts, I think the chance of this happening at the track today is very low. The greater threat of severe weather will be east of Watkins Glen, where storms will have more time to develop in an unstable air mass this afternoon. Lightning will be a threat at the track today, so have a plan to seek shelter when thunder is heard. I do expect that most of the showers will exit in time for the CTSC race, which is scheduled to start at 2:25 pm. 

I don't have a new forecast graphic today, because my thinking for Sunday is pretty much unchanged from yesterday. It will be a partly cloudy day, with temperatures reaching to around 80 degrees in the afternoon. There is a slight chance of showers developing in the afternoon as an upper level trough will linger over the region. The timing for potential showers on Sunday appears to be after 2 pm. I'd put the chance of rain during the race at just 20%. A dry race continues to be the most likely scenario right now.

By Doug Schneider - @Race4caster

The rain managed to avoid Watkins Glen yesterday, passing to the north and to the south. That won't repeat today. Here's a look at the big picture radar this morning:

Movement of the rain in the image is toward the northeast (Watkins Glen is at the red dot). The first area of rain that is over western New York and northern Pennsylvania will produce some light rain at the track this morning, mainly between 8 and 10 am. Only a few hundredths of an inch can be expected from this initial round, and a period of dry conditions and partial sunshine can be expected behind it late in the morning and early in the afternoon.

A second area of rain is located over Ohio, associated with a disturbance in the mid and upper levels of the atmosphere. It is this disturbance that will bring numerous showers and storms to the track this afternoon, and it will be aided by increasing instability as temperatures warm up. The most likely time period for storms will be between noon and 5 pm, so the Prototype Challenge and Lamborghini Super Trofeo races may be impacted, with wet conditions or possibly delays. There is a slight risk of severe storms, capable of producing damaging winds and hail. While the chance of a severe storm is low, lightning and heavy rain will be the greater risks at the track today, and fans at the track need to stay aware of the weather and be prepared to seek shelter once thunder is heard. If you can hear thunder, you are close enough to be struck by lightning. 

Storms this afternoon will move east by sunset, and the overnight hours should mostly be dry. But the chance of rain will increase again on Saturday. I expect that there will be a greater impact on the racing, due to a better chance of heavier rain and strong or severe storms than today. A cold front will move across the area, and storms ahead of it are expected from the late morning into the early afternoon. Gusty winds, heavy rain, and lightning can be expected. Again, there is a slight risk that storms in the area will be severe, capable of producing damaging winds and large hail. All storms will produce lightning and heavy rainfall. If a storm passes directly over the track, a quick half inch of rain may fall.

It's a little hard to be specific on timing, but right now I think the window for the best chance of rain Saturday will be between 10 am and 4 pm. I would not be surprised if IMSA WeatherTech qualifying was cancelled. The start of the CTSC race will likely be impacted by wet conditions, or possibly delayed. 

The timing of this system is looking a little faster than before, and I'm confident that the front will be through the area Saturday evening. The storms associated with the front will be long gone by Sunday morning, however there will still be an upper level trough over the area, so I can't completely rule out the chance of an isolated shower on Sunday. It is most likely that the entire 6-hour race will stay dry. If there are showers in the area, they are most likely to occur in the mid to late afternoon when a little instability can develop, near the end or after the end of the race. 

Our radar link at the top of the page is up and running for Watkins Glen to help you stay aware of approaching storms. 

By Doug Schneider - @Race4caster

The general weather pattern hasn't changed much since my original forecast, but my confidence is increasing that there will be rain at the track on Thursday, Friday, and Saturday as a couple of low pressure systems track across the region. Sunday is actually looking pretty good, and will have the best weather of the event. The details of timing and rain amounts are still a bit uncertain, and the both of those factors will determine how much impact there will be on the racing. In any case, if you're headed to the track this weekend, you will definitely want to bring your wet weather gear along. It will come in handy at some point. 

On Thursday, moisture will begin to spread into the area from the south as a low pressure system tracks across Ontario. The question about Thursday is how quickly rain will move into the area. Over the past few days, most of the models have favored the afternoon and evening hours for rain, and this timing seems to be on track. Most of the rain may come after the practice sessions for the day are done, so I only have a low impact for Thursday even though the rain chance before sunset is high. Rain amounts around a tenth seem likely before sunset. More rain is expected after sunset, possibly another quarter of an inch.

Friday continues to be the least confident day for me as Watkins Glen will be between low pressure systems, and model agreement is poor. Although the atmosphere will be very moist, there isn't a strong mechanism in the atmosphere to produce lift for rain, and this is when the models tend to do poorly. At this time, I think there is about a 50/50 chance of seeing rain at some point in the day. With some sunshine possible at times, temperatures should warm up into the mid 80s with winds from the southwest at 10-15 mph. 

The second low pressure system will track across the Great Lakes and Ontario on Friday night and Saturday, with its trailing cold front moving through Saturday night. With the warm, moist air mass in place and lift provided by the approaching front, I expect numerous showers and thunderstorms around the track on Saturday. Timing of the best rain chances is tough to pinpoint this far out, as it looks like there could be storms at any time during the day. Rainfall amounts could be somewhere in the range of 0.25 to 0.75 inches, and the rain could be heavy at times. For this reason, I've ranked the impact on Saturday as moderate. I expect there will at least be some delays to the on track action, with some cancellations possible. 

The front will move east of Watkins Glen Saturday night, but the upper level trough will lag behind slightly, which is why I have a slight chance of rain mentioned Sunday morning. I don't think any rain on Sunday will have an impact on the race, as it will be light if it even happens at all. Clouds will be decreasing through the race, and it may be mostly sunny by the end, with temperatures getting close to 80 degrees. 

We'll have our radar link at the top of the page ready to go for Watkins Glen by Thursday.