Rule
Blue Hour
Guildford - Blue Hour - London & Southeast England
Guildford, England, United Kingdom
When city lights balance with the deep blue twilight sky
Currently
Real-time conditionsCloud Cover6%
Moon Altitude17.4°
Upcoming Opportunities
When all conditions match, PhotoWeather marks an opportunity window.
Times shown in Europe/London
Next opportunity
Good Blue Hour (clear) at Sunrise
Guildford
Tomorrow · 05:22–05:36 · 1h window
Medium confidence
66%
🌉Blue Hour Quality69.4%
Cloud Cover: 0%
Moon Illumination: 6%
Moon Altitude: -8.4°
Good Blue Hour (clear) at Sunrise
Guildford
Thu, Apr 23 · 05:13–05:28
🌉Blue Hour Quality:76.6%
Medium
What this forecast looks for
Plain-language explanation from the ruleThis forecast predicts optimal blue hour conditions for London's world-class urban skyline and Southeast England's coastal scenes. We track civil twilight timing, cloud cover, and atmospheric clarity to identify when the deep blue sky will complement city lights and landmarks.
London offers some of Europe's finest blue hour photography—the contrast between modern glass towers like the Shard and historic landmarks like Tower Bridge creates visual tension that works brilliantly during twilight. Southeast coastal towns like Brighton and Whitstable add maritime character with piers and harbors lit up against twilight skies.
What makes London and Southeast blue hour exceptional:
- Iconic skyline - The Shard, Gherkin, Walkie Talkie, and Tower Bridge combine ancient and modern architecture
- Thames reflections - River mirrors the illuminated skyline creating double-exposure compositions
- Brighton Pier - Historic Victorian pier lit up against Channel twilight creates classic blue hour scene
- Whitstable harbour - Working harbor with boats, oyster shacks, and maritime character at dusk
Best conditions occur during clear or partly cloudy evenings when city lights shine bright against deep blue sky. Winter blue hour happens at convenient times (4-5pm), while summer requires late evening shooting (9-10pm). Popular viewpoints include Waterloo Bridge, Tower Bridge walkway, and South Bank.
Create your own Blue Hour alerts
Get notified when these conditions match at your own locations.
72-hour requirements breakdown
What passed or failed, hour by hourAND logic: all conditions required
Meets requirement
Misses requirement
Time Europe/London | Blue Hour Any | Blue Hour Quality ≥ 65.0% | Precipitation Chance ≤ 15.0% |
|---|---|---|---|
| Fri, Apr 17 | |||
| 20:00 | ✓ | 34% | 7.4% |
| 21:00 | ✕ | 27% | 15% |
| 22:00 | ✕ | 15% | 22% |
| 23:00 | ✕ | 15% | 22% |
| Sat, Apr 18 | |||
| 24:00 | ✕ | 15% | 22% |
| 01:00 | ✕ | 16% | 22% |
| 02:00 | ✕ | 15% | 41% |
| 03:00 | ✕ | 17% | 21% |
| 04:00 | ✕ | 17% | 0% |
| 05:00 | ✓ | 63% | 0% |
| 06:00 | ✕ | 34% | 0% |
| 07:00 | ✕ | 22% | 0% |
| 08:00 | ✕ | 19% | 14% |
| 09:00 | ✕ | 16% | 27% |
| 10:00 | ✕ | 13% | 41% |
| 11:00 | ✕ | 13% | 46% |
| 12:00 | ✕ | 16% | 51% |
| 13:00 | ✕ | 25% | 56% |
| 14:00 | ✕ | 25% | 38% |
| 15:00 | ✕ | 19% | 27% |
| 16:00 | ✕ | 16% | 0% |
| 17:00 | ✕ | 16% | 0% |
| 18:00 | ✕ | 13% | 0% |
| 19:00 | ✕ | 15% | 0% |
| 20:00 | ✓ | 60% | 0% |
| 21:00 | ✕ | 47% | 0% |
| 22:00 | ✕ | 26% | 0% |
| 23:00 | ✕ | 26% | 0% |
| Sun, Apr 19 | |||
| 24:00 | ✕ | 26% | 0% |
| 01:00 | ✕ | 26% | 0% |
| 02:00 | ✕ | 27% | 0% |
| 03:00 | ✕ | 27% | 0% |
| 04:00 | ✕ | 27% | 0% |
| 05:00 | ✓ | 69% | 0% |
| 06:00 | ✕ | 37% | 0% |
| 07:00 | ✕ | 29% | 0% |
| 08:00 | ✕ | 27% | 0% |
| 09:00 | ✕ | 28% | 0% |
| 10:00 | ✕ | 28% | 0% |
| 11:00 | ✕ | 28% | 0% |
| 12:00 | ✕ | 28% | 0% |
| 13:00 | ✕ | 28% | 0% |
| 14:00 | ✕ | 32% | 0% |
| 15:00 | ✕ | 28% | 0% |
| 16:00 | ✕ | 25% | 0% |
| 17:00 | ✕ | 21% | 0% |
| 18:00 | ✕ | 19% | 0% |
| 19:00 | ✕ | 15% | 0% |
| 20:00 | ✓ | 48% | 0% |
| 21:00 | ✕ | 47% | 0% |
| 22:00 | ✕ | 34% | 0% |
| 23:00 | ✕ | 33% | 0% |
| Mon, Apr 20 | |||
| 24:00 | ✕ | 27% | 0% |
| 01:00 | ✕ | 27% | 0% |
| 02:00 | ✕ | 27% | 0% |
| 03:00 | ✕ | 27% | 0% |
| 04:00 | ✕ | 24% | 0% |
| 05:00 | ✓ | 40% | 0% |
| 06:00 | ✕ | 20% | 0% |
| 07:00 | ✕ | 23% | 0% |
| 08:00 | ✕ | 31% | 0% |
| 09:00 | ✕ | 28% | 0% |
| 10:00 | ✕ | 28% | 0% |
| 11:00 | ✕ | 31% | 13% |
| 12:00 | ✕ | 27% | 26% |
| 13:00 | ✕ | 20% | 39% |
| 14:00 | ✕ | 19% | 26% |
| 15:00 | ✕ | 21% | 13% |
| 16:00 | ✕ | 16% | 0% |
| 17:00 | ✕ | 16% | 0% |
| 18:00 | ✕ | 16% | 0% |
| 19:00 | ✕ | 16% | 0% |
| 20:00 | ✓ | 36% | 0% |
| 21:00 | ✕ | 25% | 0% |
| 22:00 | ✕ | 22% | 0% |
| 23:00 | ✕ | 28% | 0% |
| Tue, Apr 21 | |||
| 24:00 | ✕ | 28% | 0% |
| 01:00 | ✕ | 30% | 0% |
| 02:00 | ✕ | 4% | 0% |
| 03:00 | ✕ | 4.3% | 0% |
| 04:00 | ✕ | 5% | 0% |
| 05:00 | ✓ | 30% | 13% |
| 06:00 | ✕ | 1.4% | 26% |
| 07:00 | ✕ | 2.1% | 39% |
| 08:00 | ✕ | 2% | 39% |
| 09:00 | ✕ | 2% | 39% |
| 10:00 | ✕ | 1.7% | 39% |
| 11:00 | ✕ | 1.8% | 33% |
| 12:00 | ✕ | 2.2% | 28% |
| 13:00 | ✕ | 2.5% | 22% |
| 14:00 | ✕ | 2% | 15% |
| 15:00 | ✕ | 2% | 7.4% |
| 16:00 | ✕ | 2% | 0% |
| 17:00 | ✕ | 2% | 0% |
| 18:00 | ✕ | 2% | 0% |
How to read: colored cells show whether each predicate requirement is met; highlighted rows mean the full rule matched (an opportunity).
What does Blue Hour Quality mean?
Inputs that drive the scoreThis 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 | Blue Hour | High Clouds % | Low Clouds % | Mid-Level Clouds % | Relative Humidity % | Solar Elevation ° | Total Cloud Coverage % | Visibility m | Wind Speed m/s |
|---|---|---|---|---|---|---|---|---|---|
| Sat, Apr 18
Sunrise 06:01
Sunset 20:03 | |||||||||
| 20:00 | - | 0% | 6% | 0% | 81% | 0.2° | 6% | 24135m | 4m/s |
| 21:00 ☾ | - | 0% | 5% | 0% | 87% | -8.8° | 5% | 24134m | 2.7m/s |
| 22:00 ☾ | - | 0% | 5% | 0% | 90% | -16° | 5% | 24135m | 2.5m/s |
| 23:00 ☾ | - | 0% | 5% | 0% | 91% | -22° | 5% | 24135m | 2.5m/s |
| Sun, Apr 19
Sunrise 06:01
Sunset 20:03 | |||||||||
| 24:00 ☾ | - | 0% | 5% | 0% | 92% | -26° | 5% | 24134m | 2.7m/s |
| 01:00 ☾ | - | 0% | 4% | 0% | 91% | -28° | 4% | 24135m | 2.6m/s |
| 02:00 ☾ | - | 0% | 0% | 0% | 91% | -26° | 0% | 24135m | 2.7m/s |
| 03:00 ☾ | - | 0% | 0% | 0% | 92% | -23° | 0% | 24134m | 2.7m/s |
| 04:00 ☾ | - | 0% | 0% | 0% | 92% | -17° | 0% | 24134m | 2.6m/s |
| 05:00 ☾ | - | 0% | 0% | 0% | 92% | -9.1° | 0% | 24135m | 2.6m/s |
| 06:00 | - | 0% | 0% | 0% | 93% | -0.17° | 0% | 24134m | 2.4m/s |
| 07:00 | - | 0% | 0% | 0% | 90% | 8.6° | 0% | 24135m | 2.3m/s |
| 08:00 | - | 0% | 0% | 0% | 77% | 18° | 0% | 24135m | 3.8m/s |
| 09:00 | - | 0% | 0% | 0% | 65% | 27° | 0% | 24135m | 3.8m/s |
| 10:00 | - | 0% | 0% | 0% | 56% | 36° | 0% | 24134m | 3.8m/s |
| 11:00 | - | 5% | 0% | 0% | 50% | 43° | 5% | 24134m | 3.7m/s |
| 12:00 | - | 4% | 0% | 0% | 45% | 48° | 4% | 24135m | 3.6m/s |
| 13:00 | - | 5% | 5% | 0% | 44% | 50° | 5% | 24135m | 3.6m/s |
| 14:00 | - | 9% | 5% | 5% | 44% | 48° | 9% | 24135m | 3.9m/s |
| 15:00 | - | 0% | 5% | 5% | 45% | 43° | 5% | 24134m | 3.9m/s |
| 16:00 | - | 0% | 6% | 5% | 46% | 36° | 6% | 24134m | 4.1m/s |
| 17:00 | - | 0% | 5% | 98% | 47% | 28° | 98% | 24135m | 4.2m/s |
| 18:00 | - | 0% | 11% | 5% | 55% | 18° | 11% | 24134m | 3.9m/s |
| 19:00 | - | 0% | 64% | 5% | 63% | 9.1° | 64% | 24135m | 3.1m/s |
| 20:00 | - | 0% | 69% | 5% | 61% | 0.41° | 69% | 24134m | 2.4m/s |
| 21:00 ☾ | - | 0% | 19% | 0% | 57% | -8.6° | 19% | 24135m | 2.5m/s |
| 22:00 ☾ | - | 5% | 5% | 1% | 71% | -16° | 5% | 24135m | 3.1m/s |
| 23:00 ☾ | - | 35% | 5% | 33% | 88% | -22° | 40% | 24134m | 2.9m/s |
| Mon, Apr 20
Sunrise 05:59
Sunset 20:04 | |||||||||
| 24:00 ☾ | - | 100% | 5% | 100% | 91% | -26° | 100% | 24134m | 2.6m/s |
| 01:00 ☾ | - | 100% | 5% | 100% | 92% | -27° | 100% | 24135m | 2.4m/s |
| 02:00 ☾ | - | 100% | 5% | 100% | 91% | -26° | 100% | 24134m | 1.9m/s |
| 03:00 ☾ | - | 93% | 5% | 100% | 91% | -22° | 100% | 24135m | 1.9m/s |
| 04:00 ☾ | - | 20% | 5% | 100% | 91% | -16° | 100% | 24135m | 1.4m/s |
| 05:00 ☾ | - | 5% | 5% | 100% | 90% | -8.8° | 100% | 24135m | 1.9m/s |
| 06:00 | - | 5% | 5% | 100% | 88% | 0.18° | 100% | 24134m | 2m/s |
| 07:00 | - | 0% | 5% | 69% | 82% | 8.9° | 69% | 24134m | 1.9m/s |
| 08:00 | - | 1% | 5% | 5% | 69% | 18° | 5% | 24135m | 2.7m/s |
| 09:00 | - | 0% | 5% | 5% | 59% | 27° | 5% | 24135m | 3.8m/s |
| 10:00 | - | 0% | 5% | 5% | 53% | 36° | 5% | 24134m | 4.3m/s |
| 11:00 | - | 0% | 5% | 5% | 50% | 43° | 5% | 24135m | 4.5m/s |
| 12:00 | - | 0% | 7% | 5% | 48% | 48° | 7% | 24134m | 4.7m/s |
| 13:00 | - | 1% | 64% | 1% | 48% | 50° | 64% | 24135m | 4.6m/s |
| 14:00 | - | 4% | 93% | 0% | 49% | 49° | 93% | 24134m | 5.2m/s |
| 15:00 | - | 5% | 72% | 7% | 52% | 44° | 72% | 24135m | 5.3m/s |
| 16:00 | - | 15% | 100% | 63% | 52% | 36° | 100% | 24135m | 5m/s |
| 17:00 | - | 7% | 100% | 14% | 59% | 28° | 100% | 24135m | 4.4m/s |
| 18:00 | - | 100% | 100% | 100% | 59% | 19° | 100% | 24135m | 3.6m/s |
| 19:00 | - | 88% | 100% | 100% | 62% | 9.4° | 100% | 24134m | 3.2m/s |
| 20:00 | - | 5% | 100% | 100% | 69% | 0.61° | 100% | 24134m | 3.2m/s |
| 21:00 ☾ | - | 92% | 100% | 100% | 75% | -8.3° | 100% | 24134m | 3.5m/s |
| 22:00 ☾ | - | 100% | 5% | 100% | 77% | -16° | 100% | 24134m | 3.7m/s |
| 23:00 ☾ | - | 5% | 5% | 100% | 85% | -22° | 100% | 24135m | 3.1m/s |
| Tue, Apr 21
Sunrise 05:57
Sunset 20:06 | |||||||||
| 24:00 ☾ | - | 5% | 0% | 100% | 86% | -26° | 100% | 24134m | 3m/s |
| 01:00 ☾ | - | 8% | 0% | 91% | 90% | -27° | 91% | 24135m | 2.9m/s |
| 02:00 ☾ | - | 8% | 21% | 61% | 84% | -26° | 82% | 24135m | 4.1m/s |
| 03:00 ☾ | - | 7% | 42% | 30% | 78% | -22° | 72% | 24135m | 5.3m/s |
| 04:00 ☾ | - | 7% | 62% | 0% | 72% | -16° | 62% | 24135m | 6.5m/s |
| 05:00 ☾ | - | 36% | 73% | 5% | 69% | -8.5° | 75% | 24135m | 6.6m/s |
| 06:00 | - | 66% | 83% | 11% | 67% | 0.43° | 87% | 24135m | 6.6m/s |
| 07:00 | - | 95% | 94% | 16% | 64% | 9.2° | 99% | 24135m | 6.7m/s |
| 08:00 | - | 82% | 68% | 34% | 63% | 19° | 92% | 24135m | 7.1m/s |
| 09:00 | - | 69% | 43% | 52% | 61% | 28° | 85% | 24135m | 7.4m/s |
| 10:00 | - | 56% | 17% | 70% | 60% | 36° | 78% | 24135m | 7.8m/s |
| 11:00 | - | 48% | 21% | 48% | 65% | 44° | 64% | 24135m | 7.3m/s |
| 12:00 | - | 40% | 25% | 27% | 70% | 49° | 51% | 24135m | 6.8m/s |
| 13:00 | - | 33% | 29% | 5% | 74% | 51° | 37% | 24135m | 6.4m/s |
| 14:00 | - | 55% | 21% | 3% | 75% | 49° | 58% | 24135m | 6.1m/s |
| 15:00 | - | 78% | 13% | 2% | 75% | 44° | 79% | 24135m | 5.8m/s |
| 16:00 | - | 100% | 5% | 0% | 76% | 37° | 100% | 24135m | 5.6m/s |
| 17:00 | - | 100% | 3% | 2% | 79% | 28° | 100% | 24135m | 5.2m/s |
| 18:00 | - | 100% | 2% | 3% | 83% | 19° | 100% | 24135m | 4.9m/s |
| 19:00 | - | 100% | 0% | 5% | 87% | 9.6° | 100% | 24135m | 4.6m/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