Originally Posted by
Claude.fr
True if there is a substantial depression over the Atlantic.
The more you’ll approach the sea, the less likely it is to be the case, in particular in August.
Upon entering Britanny, you can expect a so-called “ Coastal effect” generating a Thermic Breeze” , with headwinds during the day, since temperatures climb faster inland than over the sea and the opposite at night time since its the sea which cools down faster.
There’s a narrow window, in summer, when Inshore temp = offshore temp with no wind at all, twice a day.
As the crow fly, Paris isn’t that far from the coast, depending upon weather systems, that’s, IMHO, worth considering.
Indulge in a nap in the afternoon instead of fighting a headwind and ride at night, instead.
https://www.culture-maritime.com/fr/...e2_cours.xhtml
Could you explain the wind patterns for the dense (me).
Let's say I arrive Loudeac at 6 am and get to Brest at 1-3 pm, would I have the slight tailwinds until coming down into Brest down the "Roc"? And more importantly, would I expect a tailwind leaving Brest? In my three times (plus some touring in the area), it gets to 37-42F in the valleys especially Tintineac to Fougeres. Or would you advise taking an afternoon nap in Brest to profit from the wind later? The section 190km approx. from Brest to Loudeac tends to have a lot of climbing is probably the most wooded section whereas from Loudeac to Mortagne is pretty open going with wavy up and down rolling terrain w/o a lot of trees. In 2019, there was headwind in both directions on this Loudeac to Mortagne stretch and was kind of hard. I really did not think about wind that time and just rode how I felt.