The one-page brief

Totality crosses northern Spain 12 August 2026, ~20:26–20:31 CEST. In the Castilla y León focus area the Sun will be very low — about 10–11° up toward León, 7–9° over the plains, ~7° in Soria — sinking toward the west-north-west (azimuth ≈ 281–284°). Sunset follows totality by roughly 50–60 minutes. Your #1 job: a completely unobstructed horizon toward WNW, and a sky that is clear at that horizon.

Weather & eclipse tools — one tap

Timeline (Central European Summer Time)

≈ 19:29–19:36	First contact (C1) — partial phase begins
≈ 20:27–20:31	TOTALITY (C2→C3) — up to 1 m 48 s on the centre line (Melgar de Fernamental); 1 m 40 s+ across most of the León–Palencia–Burgos–Soria plains
≈ 21:12–21:25	Partial ends (C4) — in the far east the Sun sets still partially eclipsed

Where the weather is (ERA5, eclipse hour, 26 yrs)

• Ebro valley (Zaragoza plain): 28–31%, ~60% clear. Sun ~5–6°. Flat, huge road network, easy repositioning along A-2/A-68/AP-68.
• South Meseta edge of the track (Guadalajara, E Madrid): ~30–33%, sun ~6–7°, short-ish totality (near southern limit) — trade duration for sky.
• North Meseta (León–Palencia–Burgos–Valladolid): 32–38%, ~50–55% clear, longest durations (100–110 s) and the highest Sun (8–11°).
• Asturias & Cantabrian coast: 50–66% cloud — the longest totality on paper, the worst odds in practice. Only go with a locked-in clear forecast.

Picking the exact spot (low-Sun rules)

• Horizon math: at Sun altitude h, an obstacle of height H blocks it if closer than H / tan(h). At 6° a 20 m tree line must be ≥ 190 m away; a 200 m ridge ≥ 1.9 km away. At 3° double all that.
• Face WNW (az ≈ 285°). Choose east rims of wide valleys, west-facing slopes, mesa edges, reservoirs' east shores, or the sea on a west coast.
• Get modest elevation over flat land — 50–200 m above the plain lifts you over haze and heat shimmer near the horizon. Avoid summits above ~1,400 m: August afternoons breed convective cloud on the peaks themselves.
• Avoid north-facing slopes, forest clearings, deep valleys, and city skylines to your west.
• Dust/haze: the low Sun shines through a long slab of atmosphere — a dry, haze-free airmass matters almost as much as cloud. Check aerosol/Calima forecasts on the day.

Which weather model to trust (and how to read it)

Weather apps blend many models; on eclipse day the differences matter. The number after each name is the grid size — smaller grid = sees smaller clouds, but only close to the event:

AROME-HD 1.3 km AROME 2.5 km	The day-of king (≤ 2 days out). The only models fine enough to place valley fog, coastal stratus sneaking under the Cantabrians, and single convective cells over the mountains. Available in this app's Live tab and on meteoblue/Windy.
ECMWF 9 km	The planning king (2–10 days out). Statistically the best global model — use it to pick your region and watch how its eclipse-hour cloud map shifts run to run. If ECMWF and AROME agree on the day, trust them.
ICON-EU 7 km / ICON 13 km / NEMS 4 km / ALADIN 2.3 km	Good second opinions. When they all agree with ECMWF, confidence is high; when they scatter, the pattern is unstable — favour mobility over a "perfect" spot.
GFS 22 km	Coarse — use only for the long-range trend (it reaches 16 days first). Never trust GFS alone for cloud detail.

• Read layers, not the total %: switch the map/forecast to low / mid / high cloud. Low cloud kills the view; thin high cirrus often doesn't (but smears the low sun).
• Read the right hour: 20:00–21:00 CEST. A "sunny day" forecast is irrelevant if a sea of stratus rolls in at 20:15.
• Read the trend: a spot that improves in each successive run beats a slightly better spot that worsens.
• On the day, do it in the Live tab: the model selector + Compare all models button run exactly this check for your spot, and the line-of-sight check weighs the layers where your sight-line actually crosses them.

Pressure: why "high" is your friend

Yes — surface pressure matters a lot. A high-pressure area (anticyclone, ≳ 1020 hPa) means slowly sinking air, which suppresses convection, dries the mid-levels and typically delivers cloudless evenings — exactly what you want at 20:30. Watch for the Azores High extending a ridge over Iberia in the days before: that is the classic clear-eclipse setup. Two caveats: (1) on the north coast a high can still trap low marine stratus ("nortada") against the Cantabrians — another reason to stay on the southern plains; (2) a thermal low often forms over the hot interior in August afternoons — harmless, but it can spark isolated evening storms over mountains. The Live tab shows your spot's eclipse-hour pressure with the forecast.

Photography — shooting a 9° eclipse

The low sun is a gift: at ~9° altitude you can frame the eclipsed Sun WITH the landscape — silhouettes, ridgelines, human figures — instead of a dot in an empty sky.

• Exposure bible: use Xavier Jubier's exposure calculator — pick aperture/ISO, read off shutter speeds for every phase (partials with filter, diamond ring, chromosphere, corona 0.1–8 solar radii, earthshine).
• Partial phases: certified solar filter over the lens (and over the viewfinder of a DSLR). Remove it in the last ~10 s before C2 — and put it back at C3.
• Totality (~1 m 45 s): no filter. Bracket wildly — corona brightness spans 10+ stops: e.g. f/8 ISO 200 from 1/2000 s (prominences) to 1/2 s (outer corona/earthshine). Automate if you can; you'll want your eyes on the sky.
• Focal lengths: 500–1000 mm for the corona close-up (tripod + no shake), 24–70 mm for the money shot here: eclipsed Sun + glowing horizon + landscape. A second body/phone on a wide tripod shot, started before C2, is the low-effort winner.
• Focus: manual, on the Sun's limb (live view, 10× zoom) before C1; tape the ring. Disable stabilisation on the tripod.
• Phone users: lock focus/exposure (long-press), never digital-zoom, film 360° ambience + the racing shadow + the crowd; grab stills during totality only if it doesn't cost you the view.
• Timer app: Solar Eclipse Timer (iOS) talks you through every contact for your exact GPS spot — "filters off", "diamond ring", "filters on" — so you never miss a phase while shooting.
• Practice the full sequence once at 20:28 CEST on any clear evening: same sun altitude, same light.

Day-of playbook

1. T-48 h: compare ECMWF / GFS / ICON in the Live tab. Pick a primary region and a fallback ≥150 km along the track.
2. Morning of: re-run the Scout scan. Watch real clouds on the map's live satellite overlay (updates ~every 10 min).
3. T-3 h: commit. Convective cloud builds over mountains in the afternoon — if in doubt, move toward the flat, dry side (Ebro basin / dry southern plains).
4. T-40 min: be parked and set up. Roads near the centre line will jam after the eclipse; totality waits for no one before it.

Safety & what you'll see

• Eclipse glasses (ISO 12312-2) for every partial phase; filters off only during totality.
• During totality: the corona, chromosphere, likely prominences; Venus ~17° below-left of the Sun, Jupiter ~9° above-right. Low-Sun totality means dramatic 360° sunset colours.
• Shadow arrives from the WNW at ~2–3 km/s — visible racing across the landscape from an elevated spot.

Sources & further tools

• Eclipsophile — climatology deep dive (J. Anderson)
• NASA GSFC — interactive path map & Besselian elements
• ESA — official map of totality in Spain
• TheSkyLive — per-town circumstances
• Tres Eclipses (ES) — official Spanish eclipse app
• timeanddate — city times
• Junta de CyL — official observation points
• Eclipse Soria — province guide (Starlight skies)
• Hosteltur — best miradores round-up
• eclipse-solar.es — location guide
• WeatherAway — eclipse cloud forecast with low-Sun cloud layers (multi-model)
• X. Jubier — solar eclipse exposure calculator
• Solar Eclipse Timer — voice countdown app for contacts (iOS)
• Windy — visual cloud forecast maps
• AEMET — official Spanish forecasts
• EUMETSAT — live satellite of W Europe

Data: eclipse geometry computed from NASA/GSFC Besselian elements (F. Espenak), ΔT = 69.2 s; verified against the NASA path tables to <0.1 s in duration. Cloud climatology: ERA5 reanalysis via the Open-Meteo archive API, mean total cloud at 18–19 UT on 10–14 Aug 2000–2025. Live forecasts: Open-Meteo (ECMWF/GFS/ICON). Live satellite & radar overlays: RainViewer. Elevations: Copernicus DEM via Open-Meteo. This tool is for planning; always sanity-check against official sources on the day.