Any Spanish town or province, plus the guides on this site. 857 AEMET weather stations and 160 pages.
Town and province names work the same in any language, so this searches every AEMET weather station in the project. Accents are optional: type Avila or Ávila.
Heads-up: the English section has a handful of pages, but the per-province data sheets a station links to are in Spanish — they are mostly tables and numbers, so they read fine either way. Start from the coolest towns in Spain if you would rather stay in English.