By Doug Schneider
Since I'm going to be attending Petit Le Mans, I've been closely watching the models over the past few days. I thought I'd share a general overview of what I'm seeing. Unfortunately, the pattern appears to be shaping up to be a wet one.
The weather pattern for this weekend and early next week across the Southeast will feature a strong high pressure area centered over North Carolina, which will provide warm temperatures and a small (20-30%) chance of showers and thunderstorms each afternoon over north Georgia. This is a typical summer-time pattern for the region, but one that is unusually warm for October.
Since I'm going to be attending Petit Le Mans, I've been closely watching the models over the past few days. I thought I'd share a general overview of what I'm seeing. Unfortunately, the pattern appears to be shaping up to be a wet one.
The weather pattern for this weekend and early next week across the Southeast will feature a strong high pressure area centered over North Carolina, which will provide warm temperatures and a small (20-30%) chance of showers and thunderstorms each afternoon over north Georgia. This is a typical summer-time pattern for the region, but one that is unusually warm for October.
GFS model depiction of winds and moisture in the midlevels of the atmosphere on Sunday 10/7.
As we get into the middle part of next week, the high pressure ridge will be shifting eastward off the East Coast, which will produce a flow of moist air from the Gulf of Mexico and Atlantic Ocean into Georgia and the Southern Appalachians. With the high pressure area weakening its grip and greater moisture moving in, the chance of rain will be rising in the Wednesday/Thursday time frame of next week.
GFS model depiction of winds and moisture in the midlevels of the atmosphere on Wednesday 10/10.
The high pressure ridge remains off the East Coast, but a low pressure trough and cold front will begin to track east across the Great Plains late next week. This will strengthen the southerly flow and bring even more moisture into Georgia. A cold front associated with this low pressure system may move into the Southeast states next weekend, which would provide lift and make the chances of rain on race day even higher.
GFS model depiction of winds and moisture in the midlevels of the atmosphere on Saturday 10/13.
Another factor in all this is a tropical system that some the models have been showing in the Gulf of Mexico for the past few days. It's extremely difficult to make any accurate predictions about tropical cyclone formation this far out, but it has been a feature in more than one model for multiple model runs. If there is a tropical cyclone in the northern Gulf late next week, the pattern of a ridge off the East Coast and a trough in the Plains would tend to steer that system northward, into the Southeast states (the GFS model in the above images is one model that does not develop a tropical system - the ECMWF and GFS-FV3 do develop it and track it into the Southeast).
So here's what I can say today about the outlook for Petit with a moderate amount of confidence:
- A good chance of rain each day of the event, with the highest chance of rain on Saturday.
- Mild temperatures and high humidity each day.
Any other details of the forecast, such as rain amounts, have low confidence at this time. And it's WAY too soon to speculate that this will be a repeat of the rain-shortened 2015 Petit Le Mans. The weather pattern this year looks very different than it did that year.
As always, please keep in mind...
So here's what I can say today about the outlook for Petit with a moderate amount of confidence:
- A good chance of rain each day of the event, with the highest chance of rain on Saturday.
- Mild temperatures and high humidity each day.
Any other details of the forecast, such as rain amounts, have low confidence at this time. And it's WAY too soon to speculate that this will be a repeat of the rain-shortened 2015 Petit Le Mans. The weather pattern this year looks very different than it did that year.
As always, please keep in mind...
I'll have the full forecast graphic posted here on Sunday. Hopefully by then I can bring some good news for better racing weather than I'm seeing today. I have a feeling this is going to be a tough forecast.
