By Scott Martin

The activities taking place at and on the track on Saturday will stay dry as we'll have plenty of sunshine bathing the straights and twisty turns of Road America. Temperatures will start off around 62 degrees at 8:00 am underneath mainly sunny skies. There will be a few clouds to help shade you from the sun for a few minutes at a time once we get to the afternoon, but you will still need the shades, the hats, and the sunscreen. Afternoon highs look to top out at a very comfortable 78 degrees. Winds will be shifty throughout the day out of the north with some fluctuations out of the east and northeast at 5-10 MPH. Chance of any measurable rain is at 0%.

An impulse will be moving across Wisconsin throughout the day on Sunday that will bring a little lift and moisture to the area, especially during the afternoon hours. If any rain occurs, it doesn't look like it will be heavy and shouldn't cause a red flag. So, there is a 50/50 chance you may see the best racers in the world struggling for grip on a wet track. Temperatures start off around 69 degrees at 8:00 am and will warm up to around 76 degrees for the daytime high. Skies will start off partly cloudy, but more clouds will build throughout the morning and will be mostly cloudy by afternoon. Rain looks to become possible right around 12:00 pm and will be possible the afternoon and into the early evening. Winds will be out of the north to northeast at 5-10 MPH. Once again, rain chances will be around 50% for now.

By Doug Schneider

Not much has changed in the forecast for Friday and Saturday at Sebring since my initial forecast on Tuesday. A tropical upper level low pressure system is expected to move slowly west across southern Florida, which will enhance the chance of afternoon showers and thunderstorms both day.

The main impact of any showers and thunderstorms will be lightning and very heavy rainfall. Because of the potential for heavy rain to cause ponding of water on the track, and relatively high confidence of storms occurring, I have rated the Impact as Moderate. Some sessions or races may need to be stopped for a period. The good news is that any showers or storms should be short-lived, lasting maybe 20-40 minutes on average. For both Friday and Saturday, the most likely time period for showers and storms will be between 2 pm and 6 pm. 

By: Stephen McCoy

Precipitation chances for this weekend have shifted more towards overnight Friday into Saturday morning, posing little to no threat to on track sessions. Hot conditions are still expected to be present, with daily high temperatures in the upper 80's to low 90's anticipated. Dew point temperatures in the mid 70's will result in heat index values or "feels like" temperatures around 100 degrees. Though air temperatures may cool a bit in time for the races, dew point temperatures are expected to increase into the evening, causing heat index values to remain mostly consistent through the latter half of each day. Strong southerly winds in the low levels of the atmosphere will increase wind speeds at the surface, resulting in breezy conditions for Saturday afternoon.

By: Stephen McCoy

For Friday, a high pressure upper level ridge will be stretched through much of the southern US, with its edge approaching the Midwest; an accompanying surface high pressure system will be present underneath the ridge. A surface low pressure system will also be present to the west/northwest of the region in the northern plains. The combination of the cyclonic rotation around the low and the anti-cyclonic rotation around the high will result in surface winds over central Iowa from the south/southeast. The winds will help transport high levels of moisture to the region overnight Thursday into Friday morning. With similar air and dew point temperatures in the morning under a temperature inversion, fog may be possible near sunrise. Both air and dew point temperatures will increase through the day, with air temperatures reaching the upper 80's F and dew point temperatures reaching the mid 70's F. As a result of the warmer dew point temperatures, heat index values or "feels like" temperatures are expected to reach the upper 90's F. Race-time temperatures will be closer to the low 80's, though with consistent dew point temperatures, heat index values will still be in the low to mid 90's; temperatures will decrease throughout the evening. Partly to mostly cloudy skies will be present through much of the day.

A slight chance for isolated to scattered showers is also present for Friday afternoon due to the large influx of moisture over the region. Current forecast model output suggests thunderstorms in the region during the afternoon time period, though there is uncertainty on the specifics of when/where individual storms will be. Current impacts for track activities is low, however a passing storm would likely delay or possibly cancel qualifying.

During Saturday, the aforementioned surface low pressure system is expected to move eastward across the Great Lakes region, with a cold front trailing to the southwest of the center. Throughout Saturday, the front will remain to the northwest of Iowa, resulting in surface winds continuing from the south. Warmer temperatures are then expected for Saturday, with a low in the mid 70's and a high in the low 90's. Dew point temperatures in the mid to upper 70's will cause heat index values to approach triple digits in the afternoon, and could last into the evening, including the start of Saturday's race. Adding insult to injury, little cloud cover is anticipated during the day, meaning that health risks such as sunstroke, heat cramps, and heat exhaustion are a possibility.

By Doug Schneider

A wet weather pattern is expected to develop over Florida late this week, which could potentially have some impacts on the Cadillac Grand Prix events on Friday and Saturday.

There will be some dry air over Florida on Thursday, which will keep the chance of showers and thunderstorms low. Afternoon showers are pretty common this time of year at Sebring, so just a 20% chance is lower than normal. Still, if one of these showers moves over the track, it could produce brief heavy downpours. Sunshine in the morning hours will raise temperatures well into the 90s, with very humid conditions. The heat index could rise to the 100-105 range in the afternoon. 

An upper level tropical low pressure trough will be moving from east to west across the Atlantic and across Florida on Friday and Saturday. This system will bring deep moisture and instability to the area, making afternoon showers and thunderstorms likely both days. The main impact from any showers ans storms will be lightning and heavy downpours that could produce a very high amount of rain in a short period. With the high probability of rain and the potential for it to be heavy, I have the expected impact as Moderate, as ponding of water on the track could result in some delays. The increased cloud cover will help hold temperatures back to around 90 degrees.but that won't be much consolation with the high humidity.