Skip to content
PhotoWeather
Get started
More Fog Hunter in Snowdonia (Eryri)
Create your own alerts
Rule Fog Hunter

Nant Gwynant - Fog Hunter - Snowdonia (Eryri)

Beddgelert, Wales, United Kingdom

Thick, moody fog for atmospheric forest and landscape shots

Currently

Real-time conditions
Fog Probability
18%
Dewpoint Spread0.8°C
Visibility13349 (Clear)
Relative Humidity95%
Wind Speed5.1m/s (moderate winds)

Upcoming Opportunities

When all conditions match, PhotoWeather marks an opportunity window.

Times shown in Europe/London
fog weather icon
Next opportunity
Dense Fog
Nant Gwynant
Thu, Jun 11 · 19:00–20:00 · 1h window
Medium confidence
50%
🌫️Fog Probability88.8%
Dewpoint Spread: 0.2°C
Visibility: 1591 (Mist/Haze)
Relative Humidity: 99%
Wind Speed: 2.7m/s (calm conditions)
fog weather icon
Dense Fog at Sunset
Nant Gwynant
Thu, Jun 11 · 20:00–21:00
🌫️Fog Probability:100%
Medium

What this forecast looks for

Plain-language explanation from the rule

This forecast tracks when valley inversions and mountain mist create atmospheric conditions for photography in Snowdonia's glacial valleys. We monitor temperature inversions, humidity patterns, and wind conditions to predict optimal fog photography opportunities.

Snowdonia's deep glacial valleys—Nant Gwynant, Llanberis Pass, and Ogwen Valley—act as natural fog bowls where cold air settles overnight, creating spectacular valley inversions with mountain peaks rising through cloud seas. The region's high rainfall and numerous lakes add moisture to the atmosphere, producing frequent mist conditions that transform slate landscapes and mountain tarns into ethereal scenes.

What makes Snowdonia fog photography distinctive:

  • Valley inversions - Nant Gwynant and Ogwen Valley trap cold air, creating cloud seas with peaks emerging above
  • Lake mist - Llyn Padarn and Llyn Ogwen generate morning mist that drifts across mirror-still water
  • Slate atmosphere - Historic slate quarries at Llanberis create moody industrial landscapes in fog
  • Glacial cwms - Cwm Idwal's enclosed cirque traps mist, creating atmospheric waterfall scenes at Devil's Kitchen

The most reliable fog conditions occur during settled high-pressure periods in autumn and winter (September-February) when clear skies allow overnight cooling to create temperature inversions. Nant Gwynant valley is particularly prone to inversions—position yourself at higher viewpoints like Pen-y-Gwryd or along the A498 to capture peaks rising through cloud. Llyn Padarn generates morning mist that drifts past Dolbadarn Castle's tower, creating atmospheric castle scenes. Cwm Idwal's enclosed glacial bowl traps mist against the dramatic headwall of Devil's Kitchen. The timing is critical—arrive before dawn as mist typically burns off within an hour or two of sunrise. Wales's wet climate means fog is common, but our forecast identifies the photogenic conditions when visibility is just right—not too thick to lose definition, not too thin to lack atmosphere.

Create your own Fog Hunter alerts

Get notified when these conditions match at your own locations.

Get this template

72-hour requirements breakdown

What passed or failed, hour by hour
0matching hours in the next 86 hours
AND logic: all conditions required
Meets requirement
Misses requirement
Time
Europe/London
Fog Probability
≥ 75.0%
Sun, Jun 7
06:000%
07:000%
08:000%
09:000%
10:000%
11:000%
12:000%
13:000%
14:000%
15:000%
16:000%
17:000%
18:000%
19:000%
20:000%
21:0018%
22:000%
23:000%
Mon, Jun 8
24:000%
01:000%
02:000%
03:000%
04:000%
05:000%
06:000%
07:000%
08:000%
09:000%
10:000%
11:000%
12:000%
13:000%
14:000%
15:000%
16:000%
17:000%
18:000%
19:000%
20:000%
21:000%
22:000%
23:000%
Tue, Jun 9
24:000%
01:000%
02:000%
03:0018%
04:000%
05:000%
06:000%
07:000%
08:000%
09:000%
10:000%
11:000%
12:000%
13:000%
14:000%
15:000%
16:000%
17:000%
18:000%
19:000%
20:000%
21:000%
22:000%
23:000%
Wed, Jun 10
24:000%
01:000%
02:000%
03:000%
04:000%
05:000%
06:000%
07:000%
08:000%
09:000%
10:000%
11:000%
12:000%
13:000%
14:000%
15:000%
16:000%
17:000%
18:0024%
19:0027%
How to read: colored cells show whether each predicate requirement is met; highlighted rows mean the full rule matched (an opportunity).

What does Fog Probability mean?

Inputs that drive the score

This derived score summarizes multiple raw weather signals. The table below shows the supporting inputs hour by hour, so you can see what's pushing the score up or down.

Time
Europe/London
Clear Sky Probability (Ensemble)
%
Dew Point
°C
Rainfall
mm
Relative Humidity
%
Snowfall
cm
Solar Elevation
°
Temperature
°C
Total Precipitation
mm
Vapor Pressure Deficit
kPa
Visibility
m
Wind Gusts
m/s
Wind Speed
m/s
Sun, Jun 7 Sunrise 04:53 Sunset 21:38
21:00
0% 9.7°C 0.35mm 95% 0cm 3.9° 10°C 0.69mm 0.06kPa 13349m 12m/s 5.1m/s
22:00 ☾
0% 9.5°C 0.51mm 96% 0cm -3.1° 10°C 1.3mm 0.05kPa 12207m 12m/s 4.9m/s
23:00 ☾
0% 9.8°C 1.3mm 96% 0cm -8.6° 10°C 2.1mm 0.04kPa 8025m 12m/s 4.7m/s
Mon, Jun 8 Sunrise 04:53 Sunset 21:38
24:00 ☾
0% 10°C 1.6mm 97% 0cm -12° 11°C 3.4mm 0.04kPa 7032m 12m/s 5.3m/s
01:00 ☾
0% 10°C 1.3mm 97% 0cm -14° 11°C 5.2mm 0.03kPa 5425m 13m/s 6.6m/s
02:00 ☾
0% 10°C 2.3mm 98% 0cm -14° 10°C 1.4mm 0.02kPa 1040m 12m/s 6.2m/s
03:00 ☾
0% 10°C 5.4mm 99% 0cm -11° 10°C 5.3mm 0.01kPa 143m 8.2m/s 4.1m/s
04:00 ☾
0% 9.4°C 2.9mm 98% 0cm -6.1° 9.6°C 10mm 0.02kPa 707m 3.1m/s 2m/s
05:00
0% 8.5°C 0.52mm 98% 0cm 0.54° 8.8°C 12mm 0.02kPa 18128m 1.5m/s 1.3m/s
06:00
0% 8.2°C 0.08mm 99% 0cm 7.6° 8.4°C 12mm 0.01kPa 2707m 2.6m/s 2.1m/s
07:00
0% 8°C 0mm 96% 0cm 16° 8.5°C 12mm 0.04kPa 17126m 2.8m/s 1.8m/s
08:00
11% 7.5°C 0mm 89% 0cm 25° 9.2°C 0.13mm 0.13kPa 23270m 4.2m/s 2.2m/s
09:00
23% 7.1°C 0mm 84% 0cm 34° 9.7°C 0.31mm 0.19kPa 24134m 4.1m/s 2.6m/s
10:00
34% 6.6°C 0mm 81% 0cm 42° 9.8°C 0.5mm 0.23kPa 23034m 4.8m/s 3.2m/s
11:00
36% 6.9°C 0mm 81% 0cm 50° 10°C 0.81mm 0.24kPa 13949m 6m/s 4.4m/s
12:00
37% 6.8°C 0mm 78% 0cm 57° 10°C 1.1mm 0.27kPa 23385m 6.4m/s 4.7m/s
13:00
39% 5.7°C 0mm 69% 0cm 60° 11°C 1.1mm 0.4kPa 24135m 6.8m/s 4.9m/s
14:00
58% 5.3°C 0mm 66% 0cm 59° 11°C 0mm 0.47kPa 24135m 7.4m/s 5.8m/s
15:00
76% 5.5°C 0mm 66% 0cm 54° 12°C 0mm 0.46kPa 24135m 7.4m/s 5.9m/s
16:00
95% 6.5°C 0mm 73% 0cm 47° 11°C 0.06mm 0.35kPa 20781m 7.9m/s 7m/s
17:00
93% 6.9°C 0mm 78% 0cm 38° 11°C 0.19mm 0.28kPa 20361m 8.2m/s 6.4m/s
18:00
91% 7.1°C 0mm 82% 0cm 29° 10°C 0.38mm 0.22kPa 12533m 8.7m/s 6.4m/s
19:00
89% 7.6°C 0mm 86% 0cm 20° 9.7°C 0.63mm 0.16kPa 18184m 9m/s 5.4m/s
20:00
62% 7.6°C 0mm 91% 0cm 12° 9°C 0.38mm 0.1kPa 13288m 9.9m/s 5.4m/s
21:00
35% 7.3°C 0mm 92% 0cm 4° 8.5°C 0.88mm 0.09kPa 22829m 10m/s 4.9m/s
22:00 ☾
8% 7.2°C 0.01mm 94% 0cm -3° 8.2°C 1.3mm 0.07kPa 19911m 12m/s 5.3m/s
23:00 ☾
5% 7.1°C 0.07mm 92% 0cm -8.5° 8.3°C 1.8mm 0.08kPa 14166m 11m/s 5.1m/s
Tue, Jun 9 Sunrise 04:52 Sunset 21:38
24:00 ☾
3% 6.7°C 0mm 90% 0cm -12° 8.2°C 2.6mm 0.1kPa 12703m 11m/s 5.4m/s
01:00 ☾
0% 6.5°C 0.26mm 92% 0cm -14° 7.8°C 3.1mm 0.09kPa 15913m 10m/s 4.7m/s
02:00 ☾
3% 6.3°C 0.01mm 92% 0cm -13° 7.6°C 0.5mm 0.09kPa 18080m 9.9m/s 4.4m/s
03:00 ☾
6% 6°C 0mm 96% 0cm -11° 6.6°C 0.88mm 0.04kPa 21163m 10m/s 3.8m/s
04:00 ☾
9% 5.4°C 0mm 97% 0cm -6.1° 5.8°C 1.1mm 0.02kPa 20093m 9.9m/s 3.6m/s
05:00
8% 5.6°C 0mm 94% 0cm 0.58° 6.6°C 1.2mm 0.06kPa 24134m 11m/s 4.8m/s
06:00
8% 5.6°C 0mm 94% 0cm 7.7° 6.5°C 1.4mm 0.06kPa 17607m 11m/s 5.6m/s
07:00
7% 6.2°C 0mm 94% 0cm 16° 7.2°C 1.8mm 0.06kPa 13186m 12m/s 6.8m/s
08:00
11% 5.9°C 0mm 91% 0cm 25° 7.2°C 0.31mm 0.09kPa 23254m 11m/s 7.6m/s
09:00
15% 5.9°C 0.03mm 94% 0cm 34° 6.9°C 0.44mm 0.06kPa 23107m 10m/s 6.1m/s
10:00
19% 6.1°C 0.01mm 92% 0cm 43° 7.3°C 0.5mm 0.08kPa 24134m 11m/s 6.2m/s
11:00
20% 6.2°C 0mm 90% 0cm 50° 7.8°C 0.56mm 0.11kPa 24135m 11m/s 7m/s
12:00
20% 7.3°C 0mm 82% 0cm 57° 10°C 0.81mm 0.22kPa 23546m 12m/s 9.2m/s
13:00
21% 7.2°C 0mm 78% 0cm 60° 11°C 1.1mm 0.29kPa 23879m 11m/s 9m/s
14:00
41% 7.4°C 0mm 76% 0cm 59° 11°C 0.31mm 0.32kPa 18583m 12m/s 8.9m/s
15:00
62% 8.2°C 0mm 84% 0cm 54° 11°C 0.63mm 0.21kPa 16518m 11m/s 8.4m/s
16:00
82% 8.1°C 0mm 83% 0cm 47° 11°C 1mm 0.22kPa 21890m 11m/s 8m/s
17:00
75% 7.9°C 0mm 79% 0cm 38° 11°C 1.3mm 0.28kPa 19911m 10m/s 7.8m/s
18:00
67% 8.2°C 0mm 84% 0cm 29° 11°C 1.6mm 0.21kPa 21359m 9.7m/s 7.1m/s
19:00
60% 8.2°C 0mm 86% 0cm 21° 10°C 2.1mm 0.18kPa 13882m 9.4m/s 6m/s
20:00
44% 7.5°C 0mm 87% 0cm 12° 9.6°C 0.5mm 0.16kPa 12673m 9.7m/s 5.1m/s
21:00
29% 6.8°C 0mm 88% 0cm 4.1° 8.7°C 0.75mm 0.14kPa 24134m 9.4m/s 3.8m/s
22:00 ☾
13% 6.1°C 0mm 90% 0cm -2.9° 7.7°C 0.88mm 0.11kPa 24135m 3.1m/s 2.3m/s
23:00 ☾
10% 5.8°C 0mm 90% 0cm -8.4° 7.4°C 0.94mm 0.11kPa 23884m 1.8m/s 1.6m/s
Wed, Jun 10 Sunrise 04:52 Sunset 21:39
24:00 ☾
8% 5.1°C 0mm 90% 0cm -12° 6.5°C 1mm 0.09kPa 23418m 1.2m/s 1.3m/s
01:00 ☾
5% 4.8°C 0mm 92% 0cm -14° 6.1°C 1.1mm 0.08kPa 23088m 1.5m/s 1.6m/s
02:00 ☾
5% 5.5°C 0mm 90% 0cm -13° 7.1°C 0.98mm 0.1kPa 20208m 3.9m/s 3m/s
03:00 ☾
5% 6.2°C 0mm 88% 0cm -11° 8.1°C 0.9mm 0.13kPa 17327m 6.2m/s 4.4m/s
04:00 ☾
5% 6.9°C 0mm 86% 0cm -6° 9.1°C 0.81mm 0.16kPa 14447m 8.6m/s 5.8m/s
05:00
4% 7.1°C 0.05mm 84% 0cm 0.62° 9.7°C 1.2mm 0.2kPa 17369m 8.8m/s 6.3m/s
06:00
3% 7.2°C 0.09mm 81% 0cm 7.7° 10°C 1.5mm 0.23kPa 20291m 9.1m/s 6.8m/s
07:00
2% 7.4°C 0.14mm 79% 0cm 16° 11°C 1.9mm 0.27kPa 23213m 9.3m/s 7.3m/s
08:00
6% 7.5°C 0.09mm 79% 0cm 25° 11°C 1.5mm 0.27kPa 20775m 9.3m/s 7.3m/s
09:00
11% 7.7°C 0.05mm 80% 0cm 34° 11°C 1.2mm 0.27kPa 18338m 9.3m/s 7.3m/s
10:00
15% 7.9°C 0mm 80% 0cm 43° 11°C 0.88mm 0.26kPa 15900m 9.4m/s 7.3m/s
11:00
13% 7.8°C 0.1mm 85% 0cm 51° 10°C 1.5mm 0.19kPa 17243m 6.9m/s 5.3m/s
12:00
11% 7.7°C 0.19mm 89% 0cm 57° 9.4°C 2.1mm 0.13kPa 18585m 4.4m/s 3.3m/s
13:00
9% 7.5°C 0.29mm 94% 0cm 60° 8.5°C 2.8mm 0.07kPa 19927m 2m/s 1.3m/s
14:00
13% 6.8°C 0.2mm 93% 0cm 59° 7.8°C 1.9mm 0.07kPa 21330m 2m/s 1.7m/s
15:00
16% 6°C 0.1mm 93% 0cm 54° 7.1°C 1.1mm 0.07kPa 22732m 2.1m/s 2m/s
16:00
20% 5.3°C 0.01mm 92% 0cm 47° 6.5°C 0.31mm 0.07kPa 24135m 2.2m/s 2.3m/s
17:00
20% 5.2°C 0.01mm 94% 0cm 38° 6.1°C 0.35mm 0.06kPa 24135m 2.1m/s 2.2m/s
18:00
19% 5°C 0.02mm 95% 0cm 30° 5.8°C 0.4mm 0.05kPa 24135m 2m/s 2m/s
19:00
19% 4.8°C 0.02mm 96% 0cm 21° 5.4°C 0.44mm 0.03kPa 24135m 1.9m/s 1.9m/s
20:00
16% 4.9°C 0.01mm 97% 0cm 12° 5.4°C 0.31mm 0.03kPa 24135m 1.8m/s 1.8m/s
How to read: these inputs help produce the derived score; they are not requirements by themselves.

Get Notified of Opportunities

Create your own custom alerts for this location and more.

Create Free Account