Every score chip on the site’s own municipality table and every shade of the map’s “scoring” layer comes from the same formula, applied identically to all 3,963 towns inside the totality band. It weighs three things: how long totality lasts (40% of the score), how much clearance the Sun has over the western horizon (30%), and the 30-year odds of a clear sky on 12 August (30%). Run that formula across the whole dataset and sort by the result, and this is what comes out on top.
The formula, reproduced
Duration counts linearly up to a 110-second cap (the national maximum, at El Franco, Asturias) — a town at 55 seconds gets half credit, one at 110 gets full credit. Horizon clearance counts linearly too, but caps out at just 2° of margin: once the Sun clears the ridge by two degrees or more, extra buffer stops adding to the score (it can still matter in practice — see our piece on the 85 towns the terrain blocks — but the model treats “plenty of clearance” as good enough past that point). Climate counts as the straight percentage of the 30 years that came up clear on 12 August. Multiply each by its weight and add them up, times 100, and you get the score out of 100.
The actual top 20
| # | Town | Province | Score | Duration | Horizon margin | 30-yr clear |
|---|---|---|---|---|---|---|
| 1 | Torreblanca | Castelló/Castellón | 85.5 | 99s | 2.7° | 65.1% |
| 2 | Quintanilla de la Mata | Burgos | 84.9 | 106s | 8.1° | 54.4% |
| 3 | Villafruela | Burgos | 84.6 | 105s | 7.9° | 54.6% |
| 4 | Espinosa de Cerrato | Palencia | 84.5 | 105s | 7.7° | 54.4% |
| 5 | Avellanosa de Muñó | Burgos | 84.5 | 105s | 7.7° | 54.4% |
| 6 | Fontioso | Burgos | 84.5 | 106s | 8.2° | 53.2% |
| 7 | Iglesiarrubia | Burgos | 84.5 | 105s | 8.0° | 54.4% |
| 8 | Lerma | Burgos | 84.5 | 105s | 7.8° | 54.4% |
| 9 | Royuela de Río Franco | Burgos | 84.4 | 105s | 7.4° | 54.1% |
| 10 | Cihuela | Soria | 84.3 | 103s | 6.4° | 56.1% |
| 11 | Alcaine | Teruel | 84.3 | 100s | 4.4° | 59.9% |
| 12 | Valdehorna | Zaragoza | 84.3 | 102s | 3.2° | 57.3% |
| 13 | Pinilla Trasmonte | Burgos | 84.3 | 105s | 7.7° | 53.8% |
| 14 | Zorita del Maestrazgo | Castelló/Castellón | 84.2 | 99s | 2.6° | 60.7% |
| 15 | Forcall | Castelló/Castellón | 84.2 | 100s | 2.6° | 59.5% |
| 16 | Alhama de Aragón | Zaragoza | 84.2 | 103s | 6.6° | 55.9% |
| 17 | Carenas | Zaragoza | 84.2 | 103s | 4.3° | 55.9% |
| 18 | Contamina | Zaragoza | 84.2 | 103s | 6.6° | 55.9% |
| 19 | Cetina | Zaragoza | 84.2 | 103s | 6.2° | 55.8% |
| 20 | Antigüedad | Palencia | 84.2 | 105s | 8.2° | 53.5% |
Tied at 84.2: twelve towns share that score at the precision our dataset publishes, for only seven slots (14–20). The scoring model itself doesn’t break the tie — tied is tied — so we order by 30-year clear-sky odds (highest first, alphabetical if that also ties): the same criterion that explains why Torreblanca takes #1 below, applied here too. Of the five Burgos towns that also tied at 84.2, none makes the top 20 — their climate odds sit around 53%, worse than the rest of the tied group.
Reading the pattern
Burgos dominates by volume, with 8 of the top 20 — no surprise given it’s already the province with the most towns in the totality band (371 of them). Its towns share a signature profile: long duration (104–106s, near the 110s ceiling) and generous horizon margin (7–8°, well past the 2° cap), held back only by mid-pack climate odds around 53–55%. Those 8 slots don’t depend on the tiebreak discussed below: the other 5 Burgos towns tied at 84.2 miss the top 20 for that same climate ceiling.
Torreblanca takes #1 without the longest duration or the biggest margin. At 99 seconds and 2.7° of clearance, it doesn’t out-duration or out-margin the Burgos cluster — both of those get capped or nearly capped anyway. What separates it is climate: 65.1% odds of a clear sky, noticeably better than Burgos’s ~54%, and that’s enough to edge past towns with more raw duration once all three components are weighted and summed.
Zaragoza shows up five times, all clustered around the Ebro valley (Valdehorna, Alhama de Aragón, Carenas, Cetina, Contamina) — the same region flagged in our climate piece as a solid middle-ground bet, here showing up at the top of the list precisely because it pairs that mid-50s climate percentage with genuinely long duration (102–103s) and comfortable margin.
What the ranking doesn’t capture
A model is a simplification. It says nothing about how to actually get to Quintanilla de la Mata or Royuela de Río Franco — some of these are small villages with limited infrastructure for a sudden influx of visitors — and nothing about crowding, road access or accommodation. It also treats 2° of horizon clearance and 8° as equally “safe,” when in practice more margin is more margin. Use it as a shortlist, not a verdict: look up any of these 20 (or any of the other 3,943 scored towns) in the search above for the full picture — silhouette, exact timings and the climate detail behind the single number.