Stage 18 · 23 July 2026

Voiron → Orcières-Merlette

185.2 kmMountain — summit finish

Observed conditions from the ERA5 reanalysis archive.

Observed heat snapshot

+2.0°Cvs the 1974-2023 average at this location (ERA5): 21.7°C

28.7°Cpeak in the race window

Moderate high-risk · 23°C WBGT (est.)

Schematic — real elevation, approximate route between known points, not survey-accurate. Fill colored by temperature.

+10°C26°C+42°C

Decade trend — deviation from the 50-year mean at this location

19.8°C'74–'83

21.5°C'84–'93

21.4°C'94–'03

21.5°C'04–'13

24.3°C'14–'23

-2°C50-yr avg+2°C

A day this hot (≥23.7°C, ERA5 at this location) occurred 16× in 1974-1983 vs. 93× in 2014-2023.

WBGT is an estimate — see methodology. Data as of 2026-08-01T22:34:20.140Z.