Aurora Borealis in Bletchley
United Kingdom · 51.99°, -0.73° · geomagnetic 53.9° · needs Kp 7
Tonight in Bletchley
4%
Peak chance of a visible display tonight, from the same model the Revon app runs. Bletchley needs Kp 7 to see anything at all, and tonight the forecast peaks at Kp 5.7. Short of the threshold, which is what most nights look like here.
Updated 2026-08-02 20:20 UTC
The next 30 nights in Bletchley
Every night to come, scored the same way as tonight. The best of the open week is Sunday 2 Aug at 4%. Not one of the seven reaches the Kp 7 that Bletchley needs, which is normal rather than unlucky — it averages 2.7 viable nights a year. The 23 nights past the seven-day window move with the 27-day solar rotation and are updated daily in the app.
Nights 8–30 unlock in the Revon app
See all 30 nights for Bletchley
Revon aurora model over the NOAA Kp forecast and 27-day outlook
How often the aurora borealis reaches Bletchley
2.7 nights a year, averaged across 10.0 years of records
| Storm level | Nights / year |
|---|---|
| Kp 4 | 83.4 |
| Kp 5 | 28.7 |
| Kp 6 | 9.3 |
| Kp 7 | 3.2 |
| Kp 8 | 1.2 |
NOAA planetary Kp, 2016-04-02 to 2026-03-30
Wait for an alert; do not book a week
At Kp 7, Bletchley needs a severe geomagnetic storm before anything shows above the northern horizon. Storms that size arrive a handful of times per solar cycle and announce themselves a day or two ahead. Watching for one beats picking dates and hoping.
Hours of true darkness, month by month
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 11.7 | 10.3 | 8.5 | 5.8 | 1.9 | 0.0 | 0.0 | 4.6 | 7.6 | 9.8 | 11.3 | 12.0 |
Solar declination and hour angle at −18°
Nothing to see from June to July
Through those months the sun never falls more than 18° below the Bletchley horizon, so the sky never darkens fully. Plan around the darker half of the year.
Getting clear of the light
The sky over Bletchley reads Bortle 7. Getting clear of the built-up area makes a visible difference on a marginal night.
- 75 km west-south-west — around Cotswold District → Bortle 5
- 107 km north-east — around King's Lynn and West Norfolk → Bortle 4
Falchi 2016 World Atlas (DOI: 10.5880/GFZ.1.4.2016.001)
The months that actually deliver
Counting only nights that were both stormy enough and dark enough, September, August and November came out ahead in Bletchley. That is storm season and darkness overlapping — the equinoxes tend to be geomagnetically active, and the nights are already long by then.
Darkest nights of the coming year
A bright moon washes out a weak display as effectively as street lighting. These new moons fall inside the Bletchley viewing season.
- 13 Aug 2026
- 11 Sep 2026
- 11 Oct 2026
- 09 Nov 2026
- 09 Dec 2026
- 07 Jan 2027
- 06 Feb 2027
Where it is close to a certainty
If you would rather plan a trip than wait for a storm, the nearest place with genuinely frequent aurora is Inverness, 650 km north-north-west in United Kingdom.
| Bletchley | Inverness | |
|---|---|---|
| Kp needed | 7 | 5 |
| Nights per year | 2.7 | 28.7 |
| Geomagnetic latitude | 53.9° | 59.8° |
Confirmed reports from this area
61 verified sightings were logged within 300 km of Bletchley between 2015-01-01 and 2016-12-31. Rare is not the same as impossible.
Aurorasaurus verified positive reports
Where the horizon opens up near Bletchley
The display sits low on the northern horizon, so what beats a better forecast is open ground facing that way. Height gets you above the town glow; water gives you an unbroken skyline. These are within a short drive of Bletchley.
- Furzton Lake — lake3.3 km north-west
- South Loughton Valley park — park4.3 km north-north-west
- Bow Brickhill — hill4.6 km east
- Campbell Park — park6.1 km north
- Lodge Lake — lake6.2 km north-west
- Woburn Safari Park — wildlife reserve10.0 km east
Places from GeoNames (CC BY 4.0)
What to do with the daylight
Aurora watching is a night job, and in winter that leaves a short, bright day to fill. Bletchley keeps its fortified past above ground, at The Toot, Wavendon and Bradwell Motte, and for a day when the cloud sits low, Bletchley Park and National Museum of Computing are indoors and near by.
Keep the daylight loose: the sky decides the evening, and the forecast can turn within a few hours.
Places from GeoNames (CC BY 4.0)
Where to stay
Anywhere on the outskirts of Bletchley will do; what matters is being able to step outside and check the sky without a drive first.
- Campanile Hotel- Milton Keynes 1.5 km from the centre
- Campanile Milton Keynes Fenny Stratford 1.5 km from the centre
- DoubleTree by Hilton Milton Keynes 1.8 km from the centre
- Parkside 4.2 km from the centre
- Mercure Parkside 4.2 km from the centre
- Mercure Milton Keynes Parkside House 4.2 km from the centre
Places from GeoNames (CC BY 4.0) — confirm before booking
The last nights it was visible here
Nights in the last decade when the storm was strong enough for Bletchley and the sky was dark enough to show it.
| Date | Peak |
|---|---|
| 2026-03-20 | Kp 7.0 |
| 2026-01-20 | Kp 7.67 |
| 2026-01-19 | Kp 8.67 |
| 2025-11-12 | Kp 7.33 |
| 2025-11-11 | Kp 8.67 |
NOAA planetary Kp
Know when it is worth going outside
Revon watches the Bletchley forecast and pushes an alert when the odds for tonight clear your threshold — no checking, no guessing.
Common questions about the aurora borealis in Bletchley
Can you see the aurora borealis from Bletchley?
Yes. On the last 10.0 years of NOAA Kp records, Bletchley had about 2.7 nights a year when the storm was strong enough and the sky dark enough at the same time.
What Kp index do you need to see the aurora borealis in Bletchley?
Kp 7. Bletchley sits at geomagnetic latitude 53.9°, and the auroral oval only reaches that far from the pole once activity hits Kp 7. Storms that size occur about 3.2 nights a year.
When is the best time of year to see the aurora borealis in Bletchley?
September, August and November. Those months scored highest once both conditions are counted together: geomagnetic activity and enough hours of real darkness. From June to July the sky over Bletchley never gets fully dark, so nothing is visible however strong the storm.
Where can you escape the light pollution near Bletchley?
The centre of Bletchley reads Bortle 7. The nearest sky at Bortle 4 is about 107 km north-east around King's Lynn and West Norfolk. On a marginal night that drive matters more than the forecast does.
Where is the nearest place to Bletchley with reliable aurora borealis?
Inverness, United Kingdom — 650 km north-north-west. It needs only Kp 5 and averages 28.7 viable nights a year against 2.7 in Bletchley.
Nearby towns
Forecasts for places within reach of Bletchley.