Skip to content
Rule Fog Hunter

Ha Long Bay - Fog Hunter - Vietnam

Ha Long, Quảng Ninh, Vietnam

Thick, moody fog for atmospheric forest and landscape shots

No opportunities right now
Here’s what usually blocks matches

No Fog Hunter opportunities in the next 14 days

Get notified
Free alerts · takes 30 seconds
Rule requirements (key thresholds)
Fog Probability · ≥ 75.0%

Tip: Scroll down to the 72-hour table to see exactly which condition fails hour by hour.

Most common blockers (next 72 hours)
Fog Probability 100% failing

Currently

Real-time conditions
Dewpoint Spread1.6°C
Visibility24135 (Clear)
Relative Humidity91%
Wind Speed1.8m/s (calm conditions)

Upcoming Opportunities

When all conditions match, PhotoWeather marks an opportunity window.

Times shown in Asia/Bangkok

No opportunities in the next 10 days

See the blocker timeline below to understand which conditions are preventing matches.

What this forecast looks for

Plain-language explanation from the rule

This forecast predicts when temperature inversions and morning mist create atmospheric conditions across Vietnam's mountain valleys, rice terraces, and karst landscapes. We track overnight cooling, humidity, topography, and seasonal patterns to identify when fog transforms Vietnam's highland regions into ethereal scenes.

Vietnam's dramatic elevation changes—from sea level to 10,000-foot peaks—create ideal conditions for fog formation in mountain valleys. Northern highlands around Sapa and Mu Cang Chai experience frequent morning fog, particularly during the transition between dry and wet seasons. Hill stations like Da Lat maintain cooler temperatures that promote mist formation even in tropical latitudes. The limestone karsts of Ha Long Bay and Ninh Binh develop ethereal fog conditions during cooler months.

What makes Vietnam fog photography special:

  • Terraced valleys - Sapa and Mu Cang Chai rice terraces emerge layer by layer as fog burns off, creating depth and mystery
  • Karst landscapes - Ha Long Bay limestone islands pierce through low-lying fog like ancient towers floating on clouds
  • Mountain village life - Traditional H'mong and Dao villages in Sapa appear and disappear through drifting mist during morning hours
  • Highland agriculture - Da Lat's flower farms and strawberry fields gain dreamlike quality under morning fog blankets

Sapa experiences its most reliable fog from September through November and March through May—transition seasons when temperature differentials are greatest. Early morning (5-8 AM) provides peak conditions as fog fills valleys while higher villages remain clear. Mu Cang Chai's deep valleys create spectacular inversions, especially during harvest season (late September) when golden rice terraces emerge through fog layers. Da Lat's elevation (1,500 meters) generates morning mist year-round, peaking December through March. Ninh Binh's karsts become most atmospheric during cooler months (November-February) when mist drifts through limestone formations. Arrive at viewpoints well before dawn—fog often dissipates quickly after sunrise.

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 95 hours
AND logic: all conditions required
Meets requirement
Misses requirement
Time
Asia/Bangkok
Fog Probability
≥ 75.0%
Sat, May 23
20:000%
21:000%
22:000%
23:000%
Sun, May 24
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%
Mon, May 25
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, May 26
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%
Wed, May 27
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%
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
Asia/Bangkok
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, May 24 Sunrise 05:11 Sunset 18:25
20:00
20% 26°C 0mm 91% 0cm -20° 28°C 0mm 0.33kPa 24135m 4.9m/s 1.8m/s
21:00
38% 26°C 0mm 92% 0cm -31° 27°C 0mm 0.3kPa 24135m 2.4m/s 1.3m/s
22:00
55% 26°C 0mm 92% 0cm -40° 27°C 0mm 0.31kPa 24134m 5m/s 1.7m/s
23:00
50% 26°C 0mm 92% 0cm -47° 27°C 0mm 0.31kPa 24134m 6m/s 1.6m/s
Mon, May 25 Sunrise 05:11 Sunset 18:25
24:00
46% 26°C 0mm 92% 0cm -48° 27°C 0mm 0.29kPa 24134m 5.5m/s 1.4m/s
01:00
41% 26°C 0mm 92% 0cm -45° 28°C 0mm 0.3kPa 24134m 6.3m/s 2.1m/s
02:00
40% 26°C 0mm 90% 0cm -37° 28°C 0mm 0.35kPa 24135m 11m/s 3.4m/s
03:00
38% 26°C 0mm 90% 0cm -27° 28°C 0mm 0.39kPa 24134m 12m/s 3.8m/s
04:00
37% 26°C 0mm 89% 0cm -16° 28°C 0mm 0.4kPa 24135m 11m/s 2.8m/s
05:00
40% 26°C 0mm 91% 0cm -3.1° 27°C 0mm 0.32kPa 24134m 5.2m/s 2.1m/s
06:00
42% 26°C 0mm 89% 0cm 9.9° 28°C 0mm 0.4kPa 24135m 9.3m/s 1.9m/s
07:00
45% 26°C 0mm 82% 0cm 23° 29°C 0mm 0.75kPa 24135m 9.3m/s 3.4m/s
08:00
44% 26°C 0mm 76% 0cm 37° 31°C 0mm 1.1kPa 24135m 7.9m/s 3.8m/s
09:00
43% 26°C 0mm 72% 0cm 51° 31°C 0mm 1.3kPa 24135m 7.2m/s 4.1m/s
10:00
42% 25°C 0mm 68% 0cm 65° 32°C 0mm 1.6kPa 24135m 7.6m/s 4.6m/s
11:00
47% 25°C 0mm 64% 0cm 79° 33°C 0mm 1.8kPa 24134m 8.2m/s 5.3m/s
12:00
53% 25°C 0mm 63% 0cm 87° 33°C 0mm 1.8kPa 24134m 8m/s 5.2m/s
13:00
58% 25°C 0mm 63% 0cm 73° 33°C 0mm 1.9kPa 24134m 7.4m/s 5m/s
14:00
65% 25°C 0mm 63% 0cm 59° 33°C 0mm 1.9kPa 24135m 7.1m/s 4.5m/s
15:00
71% 25°C 0mm 63% 0cm 46° 33°C 0mm 1.8kPa 24134m 6.8m/s 4.1m/s
16:00
78% 25°C 0mm 67% 0cm 32° 32°C 0mm 1.6kPa 24135m 6.2m/s 3.5m/s
17:00
80% 25°C 0mm 73% 0cm 18° 31°C 0mm 1.2kPa 24135m 5.8m/s 2.6m/s
18:00
83% 26°C 0mm 81% 0cm 29°C 0mm 0.8kPa 24134m 2.8m/s 1.7m/s
19:00
85% 26°C 0mm 86% 0cm -7.9° 28°C 0mm 0.55kPa 24135m 2.7m/s 1.7m/s
20:00
88% 26°C 0mm 88% 0cm -20° 28°C 0mm 0.47kPa 24134m 4.8m/s 1.8m/s
21:00
91% 26°C 0mm 89% 0cm -31° 28°C 0mm 0.42kPa 24134m 6.1m/s 2.1m/s
22:00
94% 26°C 0mm 90% 0cm -40° 28°C 0mm 0.36kPa 24134m 3.5m/s 1.9m/s
23:00
93% 26°C 0mm 92% 0cm -46° 28°C 0mm 0.28kPa 24134m 3.6m/s 1.9m/s
Tue, May 26 Sunrise 05:11 Sunset 18:26
24:00
92% 26°C 0mm 92% 0cm -48° 28°C 0mm 0.32kPa 24135m 3.1m/s 1.8m/s
01:00
91% 26°C 0mm 91% 0cm -45° 28°C 0mm 0.33kPa 24134m 3.6m/s 2m/s
02:00
83% 26°C 0mm 93% 0cm -37° 27°C 0mm 0.26kPa 24135m 4.2m/s 2m/s
03:00
75% 26°C 0mm 94% 0cm -27° 27°C 0mm 0.22kPa 24134m 3m/s 1.6m/s
04:00
67% 26°C 0mm 94% 0cm -16° 27°C 0mm 0.23kPa 24135m 2.3m/s 1.4m/s
05:00
68% 26°C 0mm 93% 0cm -3.1° 27°C 0mm 0.25kPa 24134m 2.6m/s 1.5m/s
06:00
70% 26°C 0mm 91% 0cm 10° 28°C 0mm 0.33kPa 24134m 3.4m/s 1.6m/s
07:00
71% 26°C 0mm 83% 0cm 23° 29°C 0mm 0.69kPa 24135m 5.2m/s 2m/s
08:00
75% 26°C 0mm 74% 0cm 37° 31°C 0mm 1.1kPa 24134m 5m/s 2.4m/s
09:00
80% 25°C 0mm 68% 0cm 51° 32°C 0mm 1.5kPa 24135m 4.7m/s 3m/s
10:00
84% 25°C 0mm 65% 0cm 65° 32°C 0mm 1.7kPa 24134m 4.9m/s 3.6m/s
11:00
88% 25°C 0mm 64% 0cm 79° 33°C 0mm 1.8kPa 24134m 4.8m/s 3.7m/s
12:00
91% 25°C 0mm 62% 0cm 87° 33°C 0mm 2kPa 24134m 4.6m/s 3.7m/s
13:00
95% 25°C 0mm 61% 0cm 73° 33°C 0mm 2kPa 24135m 4.5m/s 3.8m/s
14:00
95% 25°C 0mm 62% 0cm 59° 33°C 0mm 1.9kPa 24134m 3.9m/s 3.4m/s
15:00
95% 25°C 0mm 63% 0cm 46° 33°C 0mm 1.8kPa 24135m 3.8m/s 3.2m/s
16:00
95% 25°C 0mm 65% 0cm 32° 32°C 0mm 1.6kPa 24134m 4m/s 3m/s
17:00
96% 25°C 0mm 69% 0cm 18° 31°C 0mm 1.4kPa 24135m 4.3m/s 2.8m/s
18:00
97% 25°C 0mm 78% 0cm 5.1° 29°C 0mm 0.89kPa 24134m 4.1m/s 2.2m/s
19:00
98% 25°C 0mm 83% 0cm -7.8° 28°C 0mm 0.64kPa 24134m 4.6m/s 2.2m/s
20:00
98% 25°C 0mm 85% 0cm -20° 28°C 0mm 0.57kPa 24134m 4.8m/s 2.3m/s
21:00
99% 25°C 0mm 85% 0cm -31° 28°C 0mm 0.57kPa 24135m 5m/s 2.2m/s
22:00
99% 25°C 0mm 86% 0cm -40° 27°C 0mm 0.51kPa 24135m 5.7m/s 2.2m/s
23:00
99% 25°C 0mm 89% 0cm -46° 27°C 0mm 0.4kPa 24134m 4.9m/s 2.2m/s
Wed, May 27 Sunrise 05:11 Sunset 18:26
24:00
98% 26°C 0mm 92% 0cm -48° 27°C 0mm 0.31kPa 24135m 4.5m/s 2m/s
01:00
98% 26°C 0mm 92% 0cm -44° 27°C 0mm 0.29kPa 24134m 4.8m/s 2m/s
02:00
86% 26°C 0mm 85% 0cm -37° 29°C 0mm 0.61kPa 24134m 4.7m/s 2.6m/s
03:00
74% 26°C 0mm 77% 0cm -27° 30°C 0mm 0.99kPa 24135m 4.6m/s 3.1m/s
04:00
62% 26°C 0mm 70% 0cm -16° 32°C 0mm 1.4kPa 24135m 4.5m/s 3.6m/s
05:00
55% 26°C 0mm 68% 0cm -3° 32°C 0mm 1.5kPa 24135m 4.3m/s 3.6m/s
06:00
48% 25°C 0mm 67% 0cm 10° 32°C 0mm 1.6kPa 24135m 4.1m/s 3.6m/s
07:00
41% 25°C 0mm 65% 0cm 23° 33°C 0mm 1.7kPa 24135m 3.9m/s 3.6m/s
08:00
40% 25°C 0mm 66% 0cm 37° 32°C 0mm 1.6kPa 24135m 3.8m/s 3.4m/s
09:00
39% 25°C 0mm 67% 0cm 51° 32°C 0mm 1.6kPa 24135m 3.7m/s 3.2m/s
10:00
38% 25°C 0mm 68% 0cm 65° 32°C 0mm 1.5kPa 24135m 3.6m/s 3m/s
11:00
43% 25°C 0mm 73% 0cm 79° 30°C 0mm 1.2kPa 24135m 4.5m/s 2.9m/s
12:00
49% 25°C 0mm 79% 0cm 87° 29°C 0mm 0.85kPa 24135m 5.4m/s 2.8m/s
13:00
54% 25°C 0mm 85% 0cm 73° 28°C 0mm 0.58kPa 24135m 6.3m/s 2.7m/s
14:00
64% 25°C 0mm 85% 0cm 59° 28°C 0mm 0.56kPa 24135m 4.4m/s 2m/s
15:00
73% 25°C 0mm 86% 0cm 46° 28°C 0mm 0.53kPa 24135m 2.5m/s 1.3m/s
16:00
83% 25°C 0mm 86% 0cm 32° 27°C 0mm 0.5kPa 24135m 0.63m/s 0.58m/s
17:00
81% 25°C 0mm 88% 0cm 18° 27°C 0mm 0.44kPa 24135m 1.2m/s 0.96m/s
18:00
79% 25°C 0mm 89% 0cm 5.2° 27°C 0mm 0.38kPa 24135m 1.8m/s 1.3m/s
19:00
77% 25°C 0mm 91% 0cm -7.7° 27°C 0mm 0.33kPa 24135m 2.4m/s 1.7m/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