Ko Phi Phi weather in September

In September, Ko Phi Phi sees average daytime highs of 28°C and overnight lows near 26°C, with 289 mm of rain across 24.4 wet days and about 12 hours of daylight. It is the 10th-warmest and 2nd-wettest month of the year here.

Day-to-day highs hold fairly steady near 28°C through the month. The sky is clear or mostly clear about 4% of the time in September, and the air most often feels miserable.

Daylight stretches from about 12 h 06 min at the start of September to 11 h 54 min by month's end. Set against the rest of the year, September is Ko Phi Phi's 11th-clearest and 4th-windiest month. For the whole year in context, see Ko Phi Phi's year-round climate.

Daytime high
28°
10th warmest
Overnight low
26°
6th coldest
Rainfall
289 mm
24.4 wet days
Daylight
12 hours
6:18 AM – 6:20 PM
Cloud cover
85%
11th clearest
Wind
17 km/h
4th windiest
Solar energy
4.96 kWh/m²
Travel score
3.7
out of 10

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 28°C through the month.

A typical September day in Ko Phi Phi reaches about 28°C in the afternoon and slips back to 26°C overnight — a 2°C spread between the day's warmth and the night's chill. On most days the high lands between 27°C and 29°C. Set against its neighbours, September runs on par with August and on par with October.

24°26°28°30°32°151015202530
Avg high (°C)Avg low (°C)
12826
22826
32826
42826
52826
62826
72826
82826
92826
102826
112826
122826
132826
142826
152826
162826
172826
182826
192826
202826
212826
222826
232826
242826
252826
262826
272826
282826
292826
302826

How September really feels in Ko Phi Phi

Once humidity and wind are folded in, September averages 29 days that feel above 32°C and 0 that feel at or below 0°C — the comfort signal a plain temperature reading hides.

Days feeling ≥ 32°C
29
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

The story in September is heat — humidity pushes the afternoon "feels like" well above the raw temperature.

Ko Phi Phi weather by month

How September compares with the rest of the year at a glance. September is the 10th-warmest and 2nd-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan29° / 26°526.711.66.1
Feb29° / 26°22411.76.3
Mar29° / 27°741011.95.5
Apr29° / 27°13618.712.24.2
May29° / 27°25524.412.33.5
Jun29° / 27°23122.112.43.7
Jul29° / 27°21922.412.43.9
Aug28° / 27°25022.612.33.9
Sep28° / 26°28924.4123.7
Oct28° / 26°30028.111.83.6
Nov28° / 26°21022.811.64.0
Dec28° / 26°9712.411.65.3

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 4% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 8% of September, with mostly cloudy or overcast conditions the remaining 88%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
11288
21288
31288
41387
51387
61387
71387
81387
91387
101387
111387
121387
131387
141387
151288
161288
171288
181288
191288
201189
211189
221189
231189
241189
251090
261090
27991
28991
29991
30991

Chance of precipitation in September

Any precipitation

Ko Phi Phi gets around 289 mm of rain over 24.4 wet days in September. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 82% and peaks near 88% on the wettest days. The odds climb toward the end of the month.

0%20%40%60%80%100%151015202530
Rain chance (%)
178
278
379
479
579
680
780
880
981
1081
1181
1281
1382
1482
1582
1682
1782
1882
1982
2082
2183
2283
2383
2484
2584
2685
2786
2886
2987
3088

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

Most of September feels miserable — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, September lands in the miserable band about 59% of days. Sticky, muggy-or-worse air turns up on roughly 100% of them.

0%25%50%75%100%151015202530
Oppressive (%)Miserable (%)
13862
23961
33961
44060
54060
64159
74159
84159
94060
104060
114060
123961
133961
143961
153961
163862
173862
183961
193961
203961
214060
224060
234159
244258
254357
264555
274654
284753
294852
304951

Wind in September

Winds average 17 km/h in September.

Across September, daily wind ranges from about 17 km/h on the calmest days to 18 km/h at its breeziest. It stays fairly steady from day to day.

05101520151015202530
Wind speed (km/h)Feels
117light breeze
217light breeze
317light breeze
417light breeze
517light breeze
617light breeze
717light breeze
818light breeze
918light breeze
1018light breeze
1118light breeze
1218light breeze
1318light breeze
1418light breeze
1518light breeze
1618light breeze
1718light breeze
1818light breeze
1918light breeze
2018light breeze
2118light breeze
2218light breeze
2318light breeze
2417light breeze
2517light breeze
2617light breeze
2717light breeze
2817light breeze
2917light breeze
3017light breeze

Sunrise & sunset in September

DaylightNight

Daylight runs from about 12 h 06 min at the start of September to 11 h 54 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 12 minutes over September. Sunrise moves from 6:20 AM to 6:16 AM, and sunset from 6:29 PM to 6:12 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.16:206:29
212.16:206:29
312.16:206:28
412.16:206:27
512.16:206:27
612.16:196:26
712.16:196:26
812.16:196:25
912.16:196:25
1012.16:196:24
1112.16:196:23
1212.16:196:23
1312.16:186:22
1412.16:186:22
1512.06:186:21
1612.06:186:20
1712.06:186:20
1812.06:186:19
1912.06:186:19
2012.06:176:18
2112.06:176:18
2212.06:176:17
2312.06:176:16
2412.06:176:16
2512.06:176:15
2612.06:176:15
2712.06:166:14
2812.06:166:14
2911.96:166:13
3011.96:166:12

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.96 kWh/m².

For context, solar energy here swings from a low near 4.61 kWh/m² to a high of 6.35 kWh/m² in March across the year — September's 4.96 kWh/m² falls in the middle.

0246151015202530
Solar energy (kWh/m²)Level
15.0Bright
25.0Bright
35.0Bright
45.0Bright
55.0Bright
65.0Bright
75.0Bright
85.0Bright
95.0Bright
105.0Bright
115.0Bright
125.0Bright
134.9Bright
144.9Bright
154.9Bright
164.9Bright
174.9Bright
184.9Bright
194.9Bright
204.9Bright
214.9Bright
224.9Bright
234.9Bright
244.8Bright
254.8Bright
264.8Bright
274.8Bright
284.8Bright
294.8Bright
304.7Bright
Planning a trip in September

Hazard calendar for Ko Phi Phi

In seasonPeak

In September, Ko Phi Phi sits inside its cyclone season. The full year is below, with each hazard's peak months called out.

Ko Phi Phi sits in the North Indian Ocean cyclone zone; the season peaks May and October–November.

Cyclone
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec

Is September a good time to visit Ko Phi Phi?

Our two travel scores rate September for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

3.7
Sightseeing
9th-best month of the year
4.2
Beach & pool
11th-best month of the year

September is a weaker month for outdoor sightseeing in Ko Phi Phi.

What to pack for Ko Phi Phi in September

From September's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In September, Ko Phi Phi sees daytime highs around 28°C and nights near 26°C. Pack light clothes and rain gear. Worth having: sun protection. About 24 days see rain.

light clothesrain gearsun protection

Sea temperature near Ko Phi Phi in September

The nearest coast averages about 29°C in September — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 17 km away) is warmest in April at about 30°C and coldest in January near 28°C.

The water stays above 20°C all year — warm enough for a swim any month.

26°28°30°32°JanFebMarAprMayJunJulAugSepOctNovDecwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan28Tropical
Feb29Tropical
Mar29Tropical
Apr30Tropical
May30Tropical
Jun30Tropical
Jul30Tropical
Aug30Tropical
Sep29Tropical
Oct29Tropical
Nov29Tropical
Dec29Tropical

UV index in Ko Phi Phi in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 13 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Ko Phi Phi peaks around February 21 at about 13 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near November 22 at about 10 (extreme).

The index reaches 3 or more — the level where the WHO recommends sun protection — every month of the year.

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeFeb 21UV 13Nov 22UV 10
UV index (midday)Level
Jan11Extreme
Feb13Extreme
Mar13Extreme
Apr13Extreme
May12Extreme
Jun12Extreme
Jul11Extreme
Aug13Extreme
Sep13Extreme
Oct12Extreme
Nov10Extreme
Dec10Extreme

Air quality in Ko Phi Phi in September

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where September falls, not just the annual average.

Air quality in Ko Phi Phi is worst in April — around 16 µg/m³ PM2.5 (moderate), and holds fairly steady the rest of the year.

Modeled monthly averages (CAMS reanalysis, 2015–2024).

01020JanFebMarAprMayJunJulAugSepOctNovDecModerateGoodGoodModerateApr 1115 µg/m³Aug 2011 µg/m³
PM2.5 (µg/m³)Level
Jan15Moderate
Feb14Moderate
Mar15Moderate
Apr16Moderate
May13Moderate
Jun13Moderate
Jul13Moderate
Aug11Good
Sep12Moderate
Oct12Good
Nov12Good
Dec13Moderate
Location & terrain

Where is Ko Phi Phi?

Ko Phi Phi sits at 7.7°N, 98.8°E, 0 m above sea level, in Thailand. The nearest listed city is Ao Nang, 34 km away.

Topography around Ko Phi Phi

How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Ko Phi Phi.

Within 3 km, the terrain around Ko Phi Phi has only modest variations in elevation — a maximum elevation change of 229 m around an average of 20 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 229 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,369 m.

The land around Ko Phi Phi is covered by water (73%) and trees (24%) within 3 km, water (99%) within 16 km, and water (65%) and trees (30%) within 80 km.

3 km
229 m
16 km
229 m
80 km
1,369 m
treesgrasslandartificial surfaceswatermangroves
September weather nearby: Ao Nang 34 km · Krabi 40 km · Ban Ko Sire 42 km · Ko Lanta 42 km · Ban Talat Yai 44 km · Phuket 44 km · Ban Ratsada 45 km · Ban Talat Nua 45 km

Thailand travel facts

Travel advisory
Level 1
Exercise Normal Precautions
Power plugs
Type A / B / C
230 V · 50 Hz
Prices
≈ 31% of US
price level, 2025
GDP per capita
$8,057
2025
Happiness
6.3 / 10
World Happiness, 2025
Homicide rate
4.8
per 100k, 2011
Road deaths
32.2
per 100k/yr, 2019
Income group
Upper middle
World Bank
English
Very low
EF EPI 402
Religion
Buddhist 93%Muslim 5%Christian 1%other 1%

Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.

Data sources

Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Ko Phi Phi (7.7404°, 98.772°, elevation 0 m), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. Tropical-cyclone seasons are the published climatological basin seasons (NOAA National Hurricane Center / regional warning centres). Sea temperatures are the NOAA OISST v2.1 1991–2020 monthly climatology (public domain), sampled at the nearest ocean point. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).