Dark Sky Odds

Stargazing at Pembrokeshire Coast National Park: when is the sky clear and dark?

March is the best month for stargazing at Pembrokeshire Coast National Park: on average 29 clear, moonless hours of full darkness, and 18% of nights have at least two of them (ERA5, 2006–2025). The darkest spot we found there is darker than 91% of Europe’s land (NASA VIIRS 2025).

Data updated: 31 December 2025 · Sources and licences

Calculated 5 November 2026 · cloud cover ERA5 2006–2025 · night lights NASA VIIRS 2025

national park · United Kingdom

MarchBest month
165Clear moonless dark hours a year
91%darker than … of Europe’s land
18%Nights with ≥ 2 such hours (March)

Month by month

MonthNights with ≥ 2 such hoursClear moonless dark hoursMoonless dark hoursOf them clear
January14%2218712%
February17%2014414%
March18%2913022%
April14%178420%
May4%42518%
June0%00—
July2%1914%
August10%117615%
September11%1611514%
October12%1615310%
November9%121707%
December12%171889%

No astronomical darkness (June): the Sun stays above −18° all night.

Climate, not a forecast: these are shares of past nights (ERA5 reanalysis, 2006–2025), not a prediction for a particular night. Check a forecast before you go.

Light pollution

Darker than91% of Europe’s land
Light pollutionvery dark (darkest 5–20 %)
Sky-glow index (own, VIIRS) — Darkest spot we found0.21
Sky-glow index (own, VIIRS) — at the official map point1.47
Sky-glow index (own, VIIRS) — median across the area1.29
Darkest spot we found51.875, -5.342 (map) — within the OSM boundary

Next new moons

New moonNightMoonless dark hours that nightTypical share of good nights that month
9 November 20268–9 November 202611.09%
9 December 20268–9 December 202612.012%
7 January 20277–8 January 202711.814%
6 February 20276–7 February 202710.717%
8 March 20277–8 March 20279.018%
6 April 20276–7 April 20276.714%
6 May 20275–6 May 20273.54%
4 June 20274–5 June 20270.00%
4 July 20273–4 July 20270.02%
2 August 20271–2 August 20272.810%
31 August 202731 August 2027 – 1 September 20276.210%
30 September 202729–30 September 20278.511%

Hours with the Sun below −18° and the Moon below the horizon, on the night of the new moon, at the darkest spot.

Meteor showers

ShowerPeak nightChance of a clear peak nightMoon litMoonless dark hours (Sun < −12°)Radiant max. height
Leonids17–18 November 202615%55%6.760°
Geminids *13–14 December 202615%21%10.771°
Geminids *14–15 December 202618%29%9.371°
Quadrantids3–4 January 202737%13%12.573°
Lyrids22–23 April 202743%95%1.371°
Eta Aquariids *5–6 May 202728%0%5.810°
Eta Aquariids *6–7 May 202720%1%5.79°
Perseids *12–13 August 202715%84%3.267°
Perseids *13–14 August 202712%91%2.267°
Orionids21–22 October 202723%58%3.054°
Leonids17–18 November 202715%82%1.560°
Geminids14–15 December 202718%98%0.071°

* The peak falls in daylight in Europe, so both neighbouring nights are shown.

Clear peak night: at least 2 hours with ≤ 20 % cloud while the Sun is below −12°, on the same calendar night ± 1 in 2006–2025.

How we calculate