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Pen y Fan, Powys

51.88°N, 3.44°W · ~848m · 07:01 – 19:10
Updated 08:43
Temp
11°C
→ steady / 1hr
Wind
10.7
↓ 2.2 / 1hr
Condition
Overcast
Overcast
Score
5.3
Fair
Time
Condition
Precip mm
Precip %
Temp
Temp °C
Feels °C
Wind
Direction
Wind mph
Gust mph
Detail
Humidity %
Pressure
Vis km
UV Index
CAPE J/kg
Score
Wed 23 Sep Thu 24 Sep Fri 25 Sep Sat 26 Sep Sun 27 Sep Mon 28 Sep Tue 29 Sep Wed 30 Sep
08:00 09:00 10:00 11:00 12:00 13:00 14:00 15:00 16:00 17:00 18:00 19:00 20:00 21:00 22:00 23:00 00:00 01:00 02:00 03:00 04:00 05:00 06:00 07:00 08:00 09:00 10:00 11:00 12:00 13:00 14:00 15:00 16:00 17:00 18:00 19:00 20:00 21:00 22:00 23:00 00:00 01:00 02:00 03:00 04:00 05:00 06:00 07:00 08:00 09:00 10:00 11:00 12:00 13:00 14:00 15:00 16:00 17:00 18:00 19:00 20:00 21:00 22:00 23:00 00:00 01:00 02:00 03:00 04:00 05:00 06:00 07:00 08:00 09:00 10:00 11:00 12:00 13:00 14:00 15:00 16:00 17:00 18:00 19:00 20:00 21:00 22:00 23:00 00:00 01:00 02:00 03:00 04:00 05:00 06:00 07:00 08:00 09:00 10:00 11:00 12:00 13:00 14:00 15:00 16:00 17:00 18:00 19:00 20:00 21:00 22:00 23:00 00:00 01:00 02:00 03:00 04:00 05:00 06:00 07:00 08:00 09:00 10:00 11:00 12:00 13:00 14:00 15:00 16:00 17:00 18:00 19:00 20:00 21:00 22:00 23:00 00:00 01:00 02:00 03:00 04:00 05:00 06:00 07:00 08:00 09:00 10:00 11:00 12:00 13:00 14:00 15:00 16:00 17:00 18:00 19:00 20:00 21:00 22:00 23:00 00:00
Overcast Overcast Overcast Overcast Overcast Light drizzle Overcast Overcast Overcast Overcast Overcast Overcast Overcast Overcast Overcast Overcast Overcast Overcast Overcast Mostly cloudy Clear Clear Mostly cloudy Mostly cloudy Mostly clear around sunrise Mostly sunny Sunny intervals Sunny intervals Mostly sunny Mostly sunny Sunny intervals Overcast Overcast Mostly cloudy Sunny intervals Partly cloudy near sunset Partly cloudy Partly cloudy Mostly clear Mostly clear Partly cloudy Mostly cloudy Mostly cloudy Mostly cloudy Mostly cloudy Partly cloudy Mostly clear Mostly clear Mostly cloudy Mostly sunny Sunny intervals Light drizzle Light drizzle Light drizzle Overcast Overcast Overcast Moderate drizzle Moderate drizzle Moderate drizzle Dense drizzle Dense drizzle Dense drizzle Overcast Overcast Overcast Mostly cloudy Mostly clear Clear Clear Clear Clear Clear around sunrise Sunny Mostly sunny Mostly sunny Sunny intervals Sunny intervals Mostly cloudy Sunny intervals Sunny intervals Mostly sunny Mostly sunny Clear near sunset Clear Clear Clear Clear Clear Clear Clear Clear Clear Clear Clear Clear Mostly clear around sunrise Mostly sunny Sunny intervals Light drizzle Light drizzle Light drizzle Moderate rain Moderate rain Moderate rain Moderate drizzle Moderate drizzle Moderate drizzle Overcast Overcast Overcast Overcast Overcast Fog Overcast Overcast Overcast Overcast Overcast Overcast Overcast Overcast Overcast Overcast Overcast Overcast Overcast Overcast Overcast Mostly cloudy Mostly clear near sunset Clear Mostly clear Mostly cloudy Overcast Light drizzle Light drizzle Light drizzle Light drizzle Light drizzle Light drizzle Light drizzle Light drizzle Light drizzle Light drizzle Light drizzle Light drizzle Light drizzle Light drizzle Light drizzle Sunny intervals Sunny intervals Mostly sunny Mostly sunny Clear near sunset Clear Clear Clear Clear Clear Clear
- - - - - 0.1 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 0.1 0.1 0.1 - - - 0.5 0.5 0.5 1 1 1 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 0.1 0.1 0.1 1.5 1.5 1.5 0.5 0.5 0.5 - - - - - - - - - - - - - - - - - - - - - - - - - - - 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1 - - - - - - - - - - -
35% 35% 35% 35% 35% 100% 35% 30% 20% 10% 20% 15% 10% 10% 10% 10% 10% 10% 5% 5% 0% 0% 5% 5% 0% 0% 5% 10% 10% 15% 15% 25% 20% 10% 10% 15% 20% 20% 25% 15% 25% 25% 35% 25% 35% 25% 25% 15% 25% 20% 20% 80% 70% 70% 15% 15% 40% 80% 85% 90% 100% 100% 100% 50% 25% 25% 25% 15% 15% 15% 15% 15% 15% 5% 0% 0% 5% 5% 10% 0% 5% 5% 0% 5% 15% 20% 20% 20% 20% 20% 20% 20% 20% 20% 20% 20% 20% 15% 10% 55% 60% 60% 85% 95% 100% 95% 95% 90% 50% 35% 30% 35% 35% 35% 35% 35% 35% 35% 35% 35% 35% 35% 35% 30% 20% 15% 15% 15% 15% 15% 15% 20% 30% 35% 45% 85% 90% 90% 90% 90% 90% 85% 85% 80% 70% 75% 80% 75% 70% 70% 15% 15% 5% 0% 0% 0% 0% 0% 0% 0% 0%
 
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W W WNW WNW WNW WNW WNW NW NW NNW N NNE NNE NE ENE ENE ENE E E ESE ESE SE SSE SSE SSE SSE S S SSW SSW SSW SSW SSW SSW SSW SSW S SSW SSW SSW SSW SSW SSW SW WSW WSW SW WSW SW WSW W NW NNW N N N N NNW NNW NNW NW NW NW WNW WNW WNW W W W WSW WSW SW SW SW WSW WSW WSW WSW WSW WSW SW SW SW SW SSW S S SSE SSE SSE SSE SSE SSE SSE SSE SSE SSE SSE SSE SSE SSE S S SSE SSE S SSW SSW SW WSW W SW SSW S S SSE SSE SSE SSE SSE SSE SSE SE SSE SSE SSE SE SE SE ESE ESE E E ESE ESE ESE ESE ESE ESE ESE ESE ESE ESE ESE ESE ESE ESE ESE ESE ESE ESE ESE SE SE SE SE SE SE SE SE SSE
11 9 11 12 11 13 11 11 10 9 7 4 5 6 7 7 9 9 7 9 10 10 11 10 13 11 15 13 12 12 12 11 9 9 8 6 7 10 10 9 9 9 9 9 8 6 7 7 5 4 4 5 6 6 6 6 5 4 3 3 2 3 3 3 2 2 2 2 1 1 1 1 1 1 2 3 6 7 7 7 6 6 4 3 2 2 2 2 2 2 2 2 2 2 2 2 3 4 5 6 7 8 9 10 10 10 9 8 6 4 3 2 2 2 2 3 3 3 3 3 2 2 2 2 3 4 5 7 7 7 5 4 4 5 5 4 4 4 4 5 6 7 8 9 10 11 12 13 14 15 15 14 14 13 13 13 13 13 13 14 14
20 16 20 23 21 24 22 21 19 18 14 11 13 14 17 17 20 20 15 19 20 20 22 21 25 22 28 24 22 22 22 20 16 17 15 15 15 20 19 18 17 19 18 19 15 14 14 15 10 9 8 10 12 14 13 12 10 9 7 6 5 5 5 5 5 4 4 3 2 2 2 2 2 3 5 8 12 15 15 14 13 10 7 5 4 3 3 3 3 3 3 3 3 3 2 3 5 8 11 13 14 15 17 18 19 18 16 14 11 7 5 4 3 3 4 4 4 4 4 4 4 4 4 6 7 9 11 13 14 13 11 10 9 10 10 9 9 10 11 12 14 15 17 19 21 22 24 26 27 28 28 28 27 26 26 25 25 26 26 26 26
 
99 98 96 97 94 99 94 90 82 77 82 84 80 81 84 83 83 84 74 65 71 71 69 74 78 78 77 77 79 79 79 81 81 79 83 88 91 91 94 97 98 98 98 98 97 98 95 93 95 92 88 82 76 72 71 71 74 80 89 95 97 97 97 97 97 97 96 95 94 96 99 99 95 88 81 75 69 64 61 59 60 67 77 85 90 94 96 97 96 96 97 97 98 99 100 99 94 87 82 79 77 77 82 89 94 96 96 96 97 98 99 100 100 100 100 99 99 99 99 99 97 95 92 88 83 79 78 78 80 84 89 93 94 95 95 97 98 98 98 98 97 96 95 94 93 92 90 89 87 85 83 80 77 75 73 71 70 70 70 70 71
926 926 927 927 927 927 927 927 927 927 927 927 928 928 928 928 927 927 927 927 926 926 925 925 925 925 925 925 925 925 925 925 924 924 923 923 923 923 922 922 922 922 922 922 922 921 921 921 921 921 922 922 922 922 922 922 922 922 922 922 922 922 922 922 921 921 920 920 920 919 919 920 921 922 924 924 924 924 924 924 924 923 922 922 921 920 920 919 919 918 918 917 916 916 915 915 916 917 918 918 918 918 917 916 916 916 916 916 915 915 915 915 915 915 915 916 916 916 916 916 917 918 918 918 919 919 918 918 918 918 917 917 917 917 917 917 917 917 917 916 916 916 916 915 915 915 915 915 915 915 915 914 914 913 913 912 912 912 911 911 911
4.9 15 21.2 15 8.5 7.3 19.4 26.3 35.4 38.5 33.2 31.4 32.5 29.9 25.1 25.5 27.9 31.1 39.9 44.5 42.6 39.9 36.4 30.7 25.5 24.8 23.6 22 20.1 19.3 26.6 25 22 26.3 18.5 10.4 7.4 9.7 14.4 11.6 5.6 5.4 5.4 11.6 12.6 13.2 22.7 28.9 21.2 18.5 14.8 13.7 19.3 24.9 24.9 24.9 25 17.7 10.5 3.3 6.9 10.6 14.2 14.2 14.2 14.2 15.2 16.3 17.3 13.7 10 6.3 12.2 18.2 24.1 25 25.9 26.8 26.9 27 27.1 25.7 24.3 23 20.6 18.3 15.9 15.5 15.2 14.8 13.9 13 12 10.8 9.5 8.3 13.5 18.7 23.8 17.4 10.9 4.5 4.5 4.5 4.4 5.6 6.7 7.9 7.6 7.3 6.9 4.7 2.4 0.2 2.7 5.1 7.6 8.1 8.5 8.9 12.4 15.8 19.3 19.9 20.4 20.9 21.9 22.9 24 22.1 20.3 18.4 15.2 12 8.8 8.1 7.5 6.8 7.9 9 10.1 11.2 12.2 13.3 14.2 15 15.8 16.7 17.5 18.3 18.6 18.9 19.2 19.4 19.7 20 19.3 18.6 17.9 17.2 16.5
- 0.3 0.8 0.9 0.7 1 1.6 1.2 0.9 0.4 - - - - - - - - - - - - - - 0.2 0.4 1.1 1.9 2.7 2.7 2.2 1.3 0.8 0.3 - - - - - - - - - - - - - - 0.1 0.4 1.2 1.8 2.1 2.2 2.1 1.8 1.4 0.9 0.4 - - - - - - - - - - - - - 0.7 1.7 2.6 3.1 3.2 3 2.8 2.5 2.1 1.6 0.8 - - - - - - - - - - - - - 0.7 1.4 1.9 2.2 2.3 2.2 1.7 1.5 1.1 0.9 0.4 - - - - - - - - - - - - - 0.4 0.9 1.3 1.7 2 2.1 2.1 1.9 1.5 1.3 0.7 - - - - - - - - - - - - - 0.5 1.1 1.8 2.3 2.7 2.9 3 2.8 2.4 1.6 0.7 - - - - - -
10 10 20 20 50 50 20 10 10 10 10 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 10 20 20 10 10 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 5 10 20 30 30 30 30 20 10 10 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 20 60 80 80 70 60 40 20 0 0 0 0 0 0 0 0 0 0 0 0 0 0 10 10 0 0 10 60 130 180 190 180 150 100 40 0 0 0 0 0 0 0 0 0 0 10 20 30 30 30 30 20 20 10 10 0 0 0 0 0 0 0 0 0 0 0 0 0 0 90 230 390 540 650 700 660 560 430 280 150 60 20 0 0 0 0
4.8 5.7 4.9 4.3 4.8 4.0 4.5 4.8 5.2 5.5 6.2 7.1 6.6 6.4 5.9 5.9 5.3 5.3 6.2 6.5 6.2 6.2 5.8 6.0 5.2 5.8 4.4 4.1 4.4 4.4 4.5 4.9 5.7 6.7 7.2 7.4 7.3 6.3 6.4 6.6 6.7 6.5 6.5 6.5 7.3 7.6 7.5 7.3 8.3 8.5 7.4 7.0 6.6 6.3 6.4 6.7 7.0 7.0 8.5 8.5 8.1 8.1 8.1 8.8 8.8 8.8 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 8.7 7.9 7.3 7.2 7.4 7.7 8.1 8.6 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 10.0 8.6 8.1 7.7 6.2 5.9 4.6 4.2 4.0 4.9 5.3 5.8 6.8 7.5 8.8 8.8 8.8 8.8 8.8 8.8 8.8 8.8 8.8 8.8 8.8 8.8 8.8 8.8 8.8 7.3 6.8 6.4 6.1 7.6 8.0 8.4 8.4 8.3 7.0 8.5 7.3 7.2 7.0 6.7 6.4 7.3 6.9 6.6 6.1 5.7 5.3 4.9 4.6 4.3 4.3 4.5 4.6 4.8 5.0 5.1 5.1 5.0 4.9 4.8 4.8
Best Activity Window
WeatherDuck score WeatherDuck score Wind matters most. Rain comes next. Sky only nudges it. Temperature is off by default because layers and kit change comfort.
Day average
5.3/10
Windy, dull day
Best window
19:00-22:00
avg 6.7/10
Day average: 5.3/10
Best window: 19:00-22:00 · Avg 6.7
06:00 · Past
07:00 · Past
08:00 · 4.8/10
09:00 · 5.7/10
10:00 · 4.9/10
11:00 · 4.3/10
12:00 · 4.8/10
13:00 · 4.0/10
14:00 · 4.5/10
15:00 · 4.8/10
16:00 · 5.2/10
17:00 · 5.5/10
18:00 · 6.2/10
19:00 · 7.1/10
20:00 · 6.6/10
21:00 · 6.4/10
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
What this shows
The selected day from 06:00 to 21:00, scored from 0-10. The top line gives the day average and strongest window; the bars show how conditions rise and fall through that activity window. WeatherDuck score — Wind up to 5 mph (matters a lot) · Rain none at all (matters a fair bit) · Sky At least Mostly cloudy (matters a fair bit).
Score Customiser
WeatherDuck score
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These factors shape your score — set a comfy range for each, and how much it matters. Add more from the tray, or remove ones you don't care about. The bars update instantly.

Wind
Comfy range up to 5 mph
How much it matters
matters a lot
Rain
Comfy range none at all
How much it matters
matters a fair bit
Sky
Comfy range At least Mostly cloudy
How much it matters
matters a fair bit
Temperature
Comfy range 0 – 25°C
How much it matters
matters a fair bit
Time of day
Comfy range any time of day
How much it matters
matters a fair bit
UV
Comfy range any UV level
How much it matters
matters a fair bit
Wind direction
Comfy range any direction
How much it matters
matters a fair bit
Visibility
Comfy range at least 5 km
How much it matters
matters a fair bit
Not counted — tap to add
Day briefing

Overcast

12° / 7° · Today · Wed 23

Dry through the day with little or no measurable rain. West-northwesterly winds averaging around 8 mph with peaks near 13 mph, gusting to 24 mph. Temperatures range from 7C to 12C, turning cooler later with largely cloudy skies.

0.1 mm
Rain total
13 mph WNW
Wind max
gusts 24 mph
1.6
UV max
peak 14:00
Low
Pollen
40
Air quality
Fair
Very low
Thunder
CAPE 50
Atmosphere
Cloud avg 100%
Freezing level 3,400 mup to 3,850 m
Fog risk Low
Sun & Moon
07:01 / 19:10
Sun ↑↓
12 h 8 m
Daylight
17:59 / 02:57
Moon ↑↓
Waxing Gibbous
Moon phase
88% lit
Live rain radar
LIVE
Loading radar…
--:--
Light Moderate Heavy
Radar data by RainViewer
Is it muddy out there? 0 mm last 24 h · free account unlocks the verdict Sign up →
Ground conditions
Is it muddy out there?
A free account unlocks the local dryness verdict. No payment details.
0 mm
Last 24 h
29.2 mm
Last 7 days
Measured at Storey Arms raingauge rain gauge, 3.2 km away
Create a free account
Rain gauges and totals stay free for everyone
What to wear
Standard conditions, so dress in layers and pack a waterproof just in case.
LayerItemMaterialWhy
Base Moisture-wicking top Merino wool or synthetic; avoid cotton A good standard choice in most conditions
Mid Light fleece Micro-fleece or lightweight synthetic; down OK today (dry forecast) 12°C with mild, windy insulation
Outer Waterproof (in pack) Lightweight packable shell because UK weather changes fast Always carry because conditions shift quickly
Lower Walking trousers Quick-dry, stretch fabric Dry conditions, comfortable walking
Feet Walking boots Standard boots, good grip on mixed terrain Standard conditions
Extras Hat, gloves, gaiters Pack spare mid-layer, buff/neck gaiter Cool on ridges, so extra warmth will be useful
Pack a backup. Keep one spare layer close.
Wear from the start 4 pieces
Keep in your pack 1 layer
Add before you go Weather protection

Tap an item to see why

Essential Recommended Guidance

Guidance based on the forecast, not professional safety advice. Always use your own judgement. BMC layering guide →

Essential Recommended
This is general guidance based on forecast data, not professional safety advice. Always use your own judgement. BMC layering guide →
Inversion Outlook Forecast source Met Office Seamless
UKV 2 km with UKMO Global fallback
Likelihood labels describe the model signal, not an exact percentage chance.
Morning 00:00–12:00 · Afternoon 12:00–00:00
Up to two qualifying hours before midnight join the next morning. Bannau Brycheiniog & South Wales Valleys region
Unlikely
Wednesday morning BEST
No clear window yet.
WED MORNING
No clear window
Unlikely
WED AFTERNOON
No clear window
Unlikely
THU MORNING
No clear window
Unlikely
Tap a period for detail
Key Factors What we look for

Our inversion forecast combines five weather factors and how long favourable conditions are expected to last.

S1 · Inversion
Warm air sitting above cooler valley air — the essential ingredient for a cloud sea.
S2 · Moist Below
Whether the valley air is damp enough to form and hold cloud.
S3 · Moisture Contrast
A sharp boundary between the cloudy valley and the dry air above it.
S4 · Clear Above
Clear, dry air above the cloud layer — the better this is, the cleaner the summit views.
S5 · Wind Calm
Light winds at low levels to keep the inversion intact and the cloud sea flat.
Duration
How long the conditions hold — a sustained event gives more time to get above the clouds.
Temperature lid
0%
Valley moisture
24%
Layer contrast
0%
Summit clarity
0%
Wind speed
0%
Duration
0h
No temperature inversion detected
Marginal moisture below
No moisture contrast, diffuse profile
Saturated above, no clear cap
Too windy, mixing likely
No sustained favourable window
Create Free Account for 1 Alert
Loading…
Cloud Inversion Heatmap About this map A shaded area means several nearby locations agree — amber for possible, green for likely, blue for very likely. The bands always sit inside one another, so stronger signals appear more solid.
The purple dot marks your location.
Drag the timeline to see how the chance changes through the night.
Very likely Likely Possible
Atmospheric Profile · Brecon · 137 m
Loading… Timeline
Atmospheric profile data for Pen y Fan,GB
Surface Pressure

Humidity at Pressure Levels

Tap heights to compare both charts.

Higher humidity means the air is closer to saturation.

Temperature at Pressure Levels

Tap heights to compare both charts.

Warmer air above cooler air can indicate an inversion.

All heights shown equally.

Golden Hour
Today
DARKNESS
DAYLIGHT
06:16
06:41
07:01 Sunrise
07:21
07:46
Golden Hour · 40 min
Be at your summit by 06:41
Allow time to set up before the light show begins.
Monthly Inversion Chance
Illustrative relative chance by season
Illustrative — typical UK pattern
J
F
M
A
M
J
J
A
S
O
N
D
~2 proper inversion days per year. Mostly late autumn to spring.

Cloud inversions explained

What is a cloud inversion near Pen y Fan, Powys?

A cloud inversion happens when cool, moist air becomes trapped in valleys beneath warmer air above. If the trapped moisture turns into fog or low cloud, the hills can rise through it into clearer air and sunshine. From a summit, the result can look like a wide sea of cloud with only the higher peaks visible.

The best chance near Pen y Fan, Powys is a calm, settled night with moist valley air, a warm lid above and clearer, drier air over the tops. The bands on this page, from Unlikely to Very likely, describe the strength of that overall signal rather than a percentage promise, so always check timing, estimated cloud height and wind before setting off.

How to read this page. The headline outlook covers the surrounding region. Key Factors and the Atmospheric Profile describe the nearest available atmospheric profile.

See the dedicated Pen y Fan cloud inversion page Read the full UK cloud inversion guide See how WeatherDuck forecasts inversions
Tonight's Stargazing
12
Very poor conditions Skies look closed in — best to wait it out.
Waxing Gibbous Moon Waxing Gibbous 92%
Mostly cloudy Cloud Cover Mostly cloudy 82%
Moon Times Set 02:57 · Rise 17:59
Sky Clarity 34 km Clear
Lunar Day Day 12.1
Light Pollution View map ↓
Tonight's Aurora
Aurora & Solar Wind NOAA
3.0 Planetary Kp Very Low
Wind Speed 292 km/s
Bz 0.7 nT
Density 3.9 p/cm³
Bt 5.3 nT
No significant aurora activity expected tonight.
Observed 07:36 UTC · cached 5 min

Nightly Outlook

Tonight · 23 Sep

Waxing Gibbous · 92% illuminated

11/100
Best window 03:40–05:40 Lower cloud and a low or hidden moon.
Moon height above horizon DaylightGreen = best stargazing hours
18:00–10:00 next morning
Moonset 04:13 Sunset 19:10Sunrise 07:02
Every hour in detail
Hours after midnight are the following morning.
HourCloud coverMoon
18:00 100% Below horizon
19:00 100% Above horizon
20:00 100% Above horizon
21:00 100% Above horizon
22:00 100% Above horizon
23:00 100% Above horizon
00:00 100% Above horizon
01:00 99% Above horizon
02:00 96% Above horizon
03:00 79% Above horizon
04:00 20% Above horizon
05:00 20% Below horizon
06:00 77% Below horizon
07:00 81% Below horizon
08:00 27% Below horizon
09:00 6% Below horizon
Highest moon 26° at 23:00 Lunar day 12.1

Aurora Kp · 3-Day Forecast

NOAA SWPC · 3-hourly
Higher Kp = stronger geomagnetic activity = better aurora chances. For UK observers, Kp 4+ means aurora is possible from N. Scotland; Kp 5+ brings it across the whole UK.
Today
Wed 23 Sep
Unsettled
Peak Kp 4.3 at 21:00 UTC
Faint aurora possible from N. Scotland.
9630
4.3 · 21:00
0003060912151821
Tomorrow
Thu 24 Sep
Active
Peak Kp 5.3 at 03:00 UTC
Aurora visible across UK — best chance around 03:00 UTC.
9630
5.3 · 03:00
0003060912151821
Fri 25
Fri 25 Sep
Unsettled
Peak Kp 3.7 at 00:00 UTC
Slightly unsettled — minor activity, no aurora expected.
9630
3.7 · 00:00
0003060912151821
Aurora Forecast Map
NOAA OVATION Aurora Forecast
Global — OVATION Model
UK Focus
NOAA OVATION Model • Auto-refreshed
Your Night Sky
Meteor Showers
Coming up this year
Orionids Oct 21
Oct 2 – Nov 7
Fast, with persistent trains.
Leonids Nov 17
Nov 6 – Nov 30
Occasional storms. Fast, bright.
Geminids Dec 14
Dec 4 – Dec 20
Best of the year. Bright, multi-coloured.
Earlier this year
Quadrantids Jan 4
Jan 1 – Jan 6
Strong, short-lived peak. Bright fireballs.
Lyrids Apr 22
Apr 16 – Apr 25
Sparse, sometimes glowing trails.
Eta Aquariids May 6
Apr 19 – May 28
Best before dawn. Fast meteors.
Delta Aquariids Jul 30
Jul 12 – Aug 23
Steady rates, faint. Best late night.
Perseids Aug 12
Jul 17 – Aug 24
Bright, reliable. Best summer shower.
Light Pollution Map
Understanding the stargazing score

The stargazing score combines cloud cover and moon illumination to estimate how good conditions are for observing the night sky. Cloud cover is the dominant factor — even the darkest location is useless under heavy cloud.

The Bortle scale measures light pollution from 1 (pristine dark sky) to 9 (inner-city sky). In the UK, the best accessible sites reach Bortle 2 to 3, found in areas like Northumberland International Dark Sky Park, parts of the Lake District, Snowdonia, the Brecon Beacons, and the Scottish Highlands. At Bortle 3, the Milky Way is clearly visible and dozens of deep-sky objects are observable with binoculars.

Moon phase matters: A new moon (0% illumination) provides the darkest sky. A full moon floods the sky with light, washing out everything except planets and the brightest stars. The best stargazing combines a new or thin crescent moon with clear skies.

Practical tips: Give your eyes 20 to 30 minutes to dark-adapt after arriving at your spot. Avoid looking at phone screens (use a red-light torch instead). The hours after midnight are often best, as the atmosphere settles and any remaining cloud may clear.

Ground dryness Free with an account

Dry paths or muddy boots?

See how wet the ground is around Pen y Fan before you set off.

Your local ground report

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  • Local ground dryness
  • Moisture below the surface
  • Recent conditions and what’s ahead

Rainfall & rain gauges Nearby observations

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