Recently, we put up three new weather stations at three places along the Fossavatnsgangan route. These stations measure temparture, wind, wind direction and pressure.
These stations are located at Heiðin for the 50 km route, this is after 8 and 33 km, for the 25 km route, it is after 8 km), Nónvatn (for the 50 km route, this is after 20 and 26 km) and Mid-fell neck (for a 50 km it is after 42 km, for a 25 km walk after 17 km).
The more advanced might want to consider getting the app and adding these stations as favorites for easy access.
These stations come in addition to a weather station run by the Icelandic Met Office ski stadium Seljalandsdalur(the station is called Seljalandsdalur skíðaskáli in their systems). You could also want to get some indication from mount Þverfjall, although this mountain is higher and windier than the Fossavatnsgangan route.