

Screw stage 13. ¡La etapa reinaaaaaa! Vamos vamos. The official start of the stage is 12h04 CEST. Official coverage starts at 13h30 CEST (if I'm not mistaken).
The first big climb comes after 50kms of stretching the legs on flat roads. Then kaboom. The first kilometer of the Inharpu or Col d'Ahusquy already has slopes of 16% and 19%, followed by a kilometer at 11,8% average. The first 6km in total averages 9%. After this the climb flattens out for 2km. A last short but very hard uphill kick brings the riders to the top of the climb.
A climb with straight and mostly wide roads.
Km 62.9 - Col Inharpu 11.5 km a 7.1% - categoría 1

Next up is the Col du Soudet. It's been climbed in the Tour a few times as a pass, always quite far from the finish, just like here. Until 2015, sort of. Froome spread his wings and flew away from the ordinary people on the flanks of the Soudet, with the finish a little bit higher up in the ski-station of La Pierre-Saint-Martin. Though in 2015 they climbed it from a different side (North, from Arrette), this year they take the West side. Pretty similar in difficulty, only the W side has more irregular gradients.
A pretty long false flat run-in until the real stuff starts. The final 11km averages 8,15%. It includes some flattish sections, which means there are multiple kilometers above 10% too.
Km 111.8 - Col du Soudet 24 km a 5.2% - categoría 1

After the descent into Arrette, 15kms of valley remain until the base of Marie-Blanque, another well-known climb from the Tour. Last included in 2010, early in the stage, with the finish on the Tourmalet. Contador and Andy destroyed the competition but then a greatly anticipated mano à mano battle ended up in holding hands. Contador didn't contest the stage win to thank Andy for giving him a nice ride.
Anyway, it's the shortest climb of the day but the riders won't forget this one easily. The total average gradient of the climb (7,5%) doesn't really reflect the toughness, since the first 4-5km start rather easy. But the last 4km comes close to the definition of a murito. No less than 11% average, very regular, barely a single meter <10%.
Km 157.7 - Col de Marie-Blanque 9.2 a 7.5% - categoría 1

The descent is rather shallow, even including flattish sections in the beginning. At the end of descent in Bielle, the riders take a big right turn looking for the intermediate sprint in Laruns. This is where the last climb starts: the mythical Aubisque!
Aubisque has been climbed two times before in the history of the Vuelta (1995 and 2003), twice as a pass. In the Tour it has build up a huge status of course through many many decades. Very famous is the story about Wim Van Est in 1951, who crashed on the descent and fell into a ravine 70 metres deeper.
Most recent memory goes back to 2007, where Rasmussen resisted multiple attacks from Contador with ease and dropped him and Leipheimer in the final kilometer to win the stage. What Rasmussen couldn't resist though was a super fierceful attack by his own team that got him sent home that same evening.
Aubisque doesn't have the super steep gradients the Vuelta is so fond of, but it's really long and, especially after 3 cols, should cause some major damage.
Meta Aubisque - Gourette.16.5 km a 7.1% - categoría H

All in all a great stage. Finally a proper mountain stage in this Vuelta. It's not designed to offer possibilities for a longe range attack (God forbid that, it's still the Vuelta) but it's definitely going to separate the wheat from the calff. We're not talking seconds, but minutes. The GC is going to get a huge shake-up for sure.
Froome vs Quintana big showdown we never got in the Tour? I hope and expect so.
Weather
At the start and in the valleys, temperatures rise to 30°C. Weather at the Aubisque when the riders arrive, is 22°C and very cloudy but dry. Weak wind (8km/h) from the NW.
Top-10 GC
1. QUINTANA Nairo 7 MOVISTAR TEAM 52h 56' 29''
2. FROOME Christopher 21 TEAM SKY 52h 57' 23'' + 00' 54''
3. VALVERDE Alejandro 1 MOVISTAR TEAM 52h 57' 34'' + 01' 05''
4. CHAVES Johan Esteban 51 ORICA BIKEEXCHANGE 52h 59' 03'' + 02' 34''
5. CONTADOR Alberto 11 TINKOFF 52h 59' 37'' + 03' 08''
6. KONIG Leopold 26 TEAM SKY 52h 59' 38'' + 03' 09''
7. YATES Simon 59 ORICA BIKEEXCHANGE 52h 59' 54'' + 03' 25''
8. SCARPONI Michele 61 ASTANA PRO TEAM 53h 00' 03'' + 03' 34''
9. DE LA CRUZ David 133 ETIXX - QUICK STEP 53h 00' 14'' + 03' 45''
10. SANCHEZ GONZALEZ Samuel 37 BMC RACING TEAM 53h 00' 25'' + 03' 56''