# Northern lights in Castellón de la Plana tonight and this season

> Northern lights in Castellón de la Plana now: NOAA aurora probability, the Kp index the city needs (Kp 9) and the dark-sky season dates, calculated.

Canonical: https://kpforecast.com/castellon/
Updated on: 2026-10-09

Aurora probability over Castellón de la Plana right now from NOAA, the Kp index the city needs by geomagnetic latitude, the nights that get dark enough, calculated from the sun, and whether any guided tour passes the catalogue filter.

## In short

Northern lights in Castellón de la Plana are rare: the city sits at 42.1° N geomagnetic latitude and NOAA's rule of thumb stops at 48° for Kp 9, 5.9° short of the city. The aurora reaches here only in the strongest storms, low on the northern horizon, as on 10 to 11 May 2024 (G5), 10 October 2024 and 12 November 2025 (G4). The sky over Castellón de la Plana gets fully dark every night of the year, so the season is set by the Kp, not by the calendar. No guided aurora tour from Castellón de la Plana passes the catalogue filter of 4.3 stars and 20 reviews yet. The aurora probability over the city right now, from NOAA's OVATION model, is on this page and refreshes every 15 minutes.

## Key points

- Castellón de la Plana at 42.1° N geomagnetic lies 5.9° beyond NOAA's Kp 9 line: aurora only in the strongest storms
- The sky over Castellón de la Plana gets fully dark every night of the year, so the season is set by the Kp, not by the calendar.
- Aurora probability over Castellón de la Plana from NOAA OVATION, refreshed every 15 minutes with the fetch time shown
- No guided aurora tour in the catalogue passes the filter yet
- Kp forecast for the next 3 days in 3-hour slots, and the other places in Spain for comparison

## Aurora over Castellón de la Plana right now

Live figures on the web page, refreshed every 15 minutes.

## The Kp index Castellón de la Plana needs

Castellón de la Plana lies at 40.0° N, which is 42.1° N geomagnetic latitude on the WMM2025 dipole. NOAA's viewing tips put the edge of the auroral oval at about 66° geomagnetic for Kp 0 and move it about 2° closer to the equator with each Kp level, down to 48° at Kp 9. At 42.1° N Castellón de la Plana lies 5.9° beyond the reach of that rule even at Kp 9, so the cards on this site show Kp 9 and the aurora is a rare event here, seen low on the northern horizon in the strongest storms, as on 10 to 11 May 2024 (G5), 10 October 2024 and 12 November 2025 (G4). NOAA also notes that aurora can often be observed hundreds of kilometres equatorward of the oval's edge, so a bright display can show low on the northern horizon one Kp level earlier.

## Kp forecast for the next 3 days

Live figures on the web page, refreshed every 15 minutes.

## When the sky over Castellón de la Plana is dark enough

The aurora needs a dark sky as much as it needs Kp, and darkness is a matter of latitude and date. The sky over Castellón de la Plana gets fully dark every night of the year, so the season is set by the Kp, not by the calendar. Dates are an own calculation from the sun's declination for the latitude of Castellón de la Plana, with the US Naval Observatory definitions of twilight, and can be a day off at the edges. Clouds and moonlight are the other half of the question: the home page shows the moon phase for each of the next 27 days.

## Why Spain for the northern lights

Spain is not an aurora destination, and yet the aurora has reached it three times since 2024. On the night of 10 to 11 May 2024 a G5 storm, the strongest in two decades according to NASA, painted red and magenta skies from Galicia to Andalusia. On 10 October 2024 a second severe storm turned the sky red over the Calar Alto observatory in Almería, and on 12 November 2025 observers in Castellón recorded the aurora again around 4:30 in the morning. All three nights ran at Kp 8 or 9, one level below the Kp 9 of the table, which is the cautious rule. That is why the live figures on this page matter more than the season.
[All places in Spain with their odds tonight](/spain/).

## Castellón de la Plana compared with the other places in Spain

The table lists the 3 places in Spain on this site. All of them need Kp 9.
Place | Latitude | Geomagnetic | Kp needed | Tours
A Coruña | 43.4° N | 46.7° N | 9 | 0
Huesca | 42.1° N | 44.3° N | 9 | 0
Castellón de la Plana | 40.0° N | 42.1° N | 9 | 0

## Northern lights tours in Castellón de la Plana

No guided aurora tour from Castellón de la Plana passes the catalogue filter of 4.3 stars and 20 reviews yet. The aurora probability above does not depend on tours: a dark spot outside the lights of the town is the first thing to find.

## Castellón de la Plana in numbers for northern lights planning

| Fact | Value | Source |
|---|---|---|
| Coordinates | 40.0° N, 0.1° W | site destination list |
| Geomagnetic latitude | 42.1° N (WMM2025) | NOAA NCEI, own calculation |
| Kp needed | 9, strongest storms only | NOAA rule of thumb |
| Fully dark nights | every night of the year | own calculation (Meeus), USNO definitions |
| Tours that pass the filter | none yet, counted 9 Oct 2026 | booking catalogue |

## Frequently asked questions

### What Kp index do you need to see the northern lights in Castellón de la Plana?

Kp 9, and only in the strongest storms. NOAA's rule of thumb stops at 48° geomagnetic for Kp 9 and Castellón de la Plana sits at 42.1° N, 5.9° beyond it, so the aurora shows here low on the northern horizon, as on 10 to 11 May 2024 (G5), 10 October 2024 and 12 November 2025 (G4).

### When is the best time to see the northern lights in Castellón de la Plana?

The sky over Castellón de la Plana gets fully dark every night of the year, so the season is set by the Kp, not by the calendar. The darkest skies of the month are the 5 nights around the new moon. The home page shows the moon for each of the next 27 days.

### Can you see the northern lights in Castellón de la Plana in summer?

Yes, the sky over Castellón de la Plana gets dark enough every night of the year, so summer only shortens the window of darkness and a storm at Kp 9 is the real condition.

### How many northern lights tours are there in Castellón de la Plana?

None in the catalogue passes the filter of 4.3 stars and 20 reviews yet, so this page shows the probability and the Kp needed for Castellón de la Plana without tours.

### Is Castellón de la Plana the best place in Spain for the northern lights?

By Kp needed all 3 places in Spain on this site are level at Kp 9, Castellón de la Plana included. Clouds and light decide the rest.

### Why does the Castellón de la Plana aurora probability on this page change?

It comes from NOAA's OVATION model, a forecast for the next 30 to 90 minutes, which this site re-reads at most every 15 minutes. The Kp needed, 9, does not change: it is geography.

## Sources

- [NOAA SWPC, tips on viewing the aurora](https://www.swpc.noaa.gov/content/tips-viewing-aurora), checked on 2026-10-09
- [NOAA NCEI, World Magnetic Model 2025, geomagnetic pole](https://www.ncei.noaa.gov/products/world-magnetic-model), checked on 2026-10-09
- [NOAA SWPC, OVATION aurora forecast model](https://www.swpc.noaa.gov/products/aurora-30-minute-forecast), checked on 2026-10-09
- [US Naval Observatory, rise, set and twilight definitions](https://aa.usno.navy.mil/faq/RST_defs), checked on 2026-10-09
- [El País, 11 May 2024: an aurora lights up the skies of Spain](https://elpais.com/ciencia/2024-05-11/una-aurora-boreal-ilumina-los-cielos-de-espana-y-podria-volver-a-ser-observable-este-fin-de-semana.html), checked on 2026-10-09
- [Calar Alto Observatory, aurora on 10 October 2024](https://www.caha.es/science-mainmenu-95/meteors-and-fireballs/impressive-aurora-borealis-on-october-10th-2024), checked on 2026-10-09
- [Cadena SER, 12 November 2025: a new aurora over Castellón](https://cadenaser.com/comunitat-valenciana/2025/11/12/nueva-aurora-boreal-en-castellon-la-tercera-en-el-ultimo-ano-y-medio-radio-castellon/), checked on 2026-10-09
- [NASA, what NASA is learning from the biggest geomagnetic storm in 20 years](https://science.nasa.gov/science-research/heliophysics/what-nasa-is-learning-from-the-biggest-geomagnetic-storm-in-20-years/), checked on 2026-10-09