Keelung weather in September

In September, Keelung sees average daytime highs of 27°C and overnight lows near 26°C, with 192 mm of rain across 15.2 wet days and about 12.2 hours of daylight. It is the 4th-warmest and 3rd-wettest month of the year here.

Highs ease over the month, from about 28°C in the first days to 26°C by the end. The sky is clear or mostly clear about 36% of the time in September, and the air most often feels miserable.

Daylight stretches from about 12 h 30 min at the start of September to 11 h 48 min by month's end. Set against the rest of the year, September is Keelung's 1st-clearest and 6th-windiest month. For the whole year in context, see Keelung's year-round climate.

Daytime high
27°
4th warmest
Overnight low
26°
9th coldest
Rainfall
192 mm
15.2 wet days
Daylight
12 h 06 min
5:43 AM – 5:52 PM
Cloud cover
57%
1st clearest
Wind
20 km/h
6th windiest
Solar energy
4.79 kWh/m²
Travel score
5.7
out of 10

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 28°C in the first days to 26°C by the end.

A typical September day in Keelung reaches about 27°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 26°C and 29°C. Set against its neighbours, September runs about 2°C cooler than August and about 3°C warmer than October.

20°23°25°28°30°151015202530
Avg high (°C)Avg low (°C)
12827
22826
32826
42826
52826
62826
72826
82826
92826
102826
112826
122826
132726
142726
152726
162726
172726
182725
192725
202725
212725
222725
232725
242725
252625
262625
272625
282625
292625
302625

How September really feels in Keelung

Once humidity and wind are folded in, September averages 6 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
6
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.

Keelung weather by month

How September compares with the rest of the year at a glance. September is the 4th-warmest and 3rd-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan18° / 15°17819.410.64.3
Feb18° / 15°17217.111.14.5
Mar20° / 17°16017.611.85.1
Apr23° / 20°13314.512.65.9
May25° / 23°16314.213.26.0
Jun28° / 26°14113.213.55.4
Jul29° / 27°1039.213.45.5
Aug29° / 27°17112.812.95.3
Sep27° / 26°19215.212.25.7
Oct25° / 23°20515.511.46.0
Nov22° / 20°19517.610.85.4
Dec19° / 17°18618.910.54.8

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 36% of the time in September, the clearest month of the year.

Beyond those clear spells, partly cloudy skies cover about 16% of September, with mostly cloudy or overcast conditions the remaining 48%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
15050
24951
34951
45149
55050
65050
75149
85149
95248
105347
115347
125446
135446
145446
155446
165446
175347
185347
195347
205347
215347
225347
235248
245248
255149
265149
275149
285149
295149
305050

Chance of precipitation in September

Any precipitation

Keelung gets around 192 mm of rain over 15.2 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 50% and peaks near 55% on the wettest days. The odds climb toward the end of the month.

0%20%40%60%151015202530
Rain chance (%)
146
246
347
447
547
648
748
848
948
1048
1147
1247
1347
1448
1548
1649
1749
1850
1951
2052
2152
2252
2353
2453
2553
2653
2754
2854
2954
3055

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 46% of days. Sticky, muggy-or-worse air turns up on roughly 94% of them.

0%25%50%75%100%151015202530
Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
10142075
20152272
30152371
40162568
50162766
60172864
70172963
80183061
90283159
100293158
1103103255
1203113353
1304113352
1405123449
1505133447
1606143545
1706153543
1807163640
1907173738
2008183835
2108193933
2219204031
2319204129
2419214227
25110224325
26110224323
27110234422
28211234420
29211244419
30212244418

Wind in September

Winds average 20 km/h in September.

Across September, daily wind ranges from about 17 km/h on the calmest days to 23 km/h at its breeziest. It stays fairly steady from day to day.

0510152025151015202530
Wind speed (km/h)Feels
117light breeze
217light breeze
317light breeze
417light breeze
518light breeze
618light breeze
718light breeze
818light breeze
919light breeze
1019light breeze
1119light breeze
1219light breeze
1320light breeze
1420breezy
1520breezy
1621breezy
1721breezy
1821breezy
1921breezy
2022breezy
2122breezy
2222breezy
2322breezy
2422breezy
2522breezy
2623breezy
2723breezy
2823breezy
2923breezy
3023breezy

Sunrise & sunset in September

DaylightNight

Daylight runs from about 12 h 30 min at the start of September to 11 h 48 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 42 minutes over September. Sunrise moves from 5:37 AM to 5:49 AM, and sunset from 6:08 PM to 5:36 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.55:376:08
212.55:386:07
312.55:386:06
412.45:386:05
512.45:396:04
612.45:396:03
712.45:406:02
812.35:406:01
912.35:406:00
1012.35:415:58
1112.35:415:57
1212.25:415:56
1312.25:425:55
1412.25:425:54
1512.25:435:53
1612.15:435:52
1712.15:435:51
1812.15:445:49
1912.15:445:48
2012.05:455:47
2112.05:455:46
2212.05:455:45
2312.05:465:44
2411.95:465:43
2511.95:475:42
2611.95:475:40
2711.95:475:39
2811.85:485:38
2911.85:485:37
3011.85:495:36

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.79 kWh/m².

For context, solar energy here swings from a low near 2.08 kWh/m² to a high of 6.15 kWh/m² in July across the year — September's 4.79 kWh/m² falls in the middle.

0246151015202530
Solar energy (kWh/m²)Level
15.3Bright
25.2Bright
35.2Bright
45.2Bright
55.2Bright
65.1Bright
75.1Bright
85.1Bright
95.1Bright
105.0Bright
115.0Bright
125.0Bright
134.9Bright
144.9Bright
154.9Bright
164.8Bright
174.8Bright
184.7Bright
194.7Bright
204.6Bright
214.6Bright
224.5Bright
234.5Bright
244.5Bright
254.4Bright
264.4Bright
274.3Bright
284.3Bright
294.2Bright
304.2Bright
Planning a trip in September

Hazard calendar for Keelung

In seasonPeak

In September, Keelung sits inside its pacific typhoon season. The full year is below, with each hazard's peak months called out.

Keelung sits in the Pacific typhoon belt; the season peaks July–October.

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

Is September a good time to visit Keelung?

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

5.7
Sightseeing
4th-best month of the year
5.9
Beach & pool
4th-best month of the year

September is a reasonable time to visit Keelung for sightseeing.

What to pack for Keelung in September

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

In September, Keelung sees daytime highs around 27°C and nights near 26°C. Pack light clothes and rain gear. Worth having: sun protection and a windbreaker. About 15 days see rain.

light clothesrain gearsun protectiona windbreaker

Sea temperature near Keelung in September

The nearest coast averages about 27°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 14 km away) is warmest in August at about 28°C and coldest in January near 21°C.

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

20°25°30°JanFebMarAprMayJunJulAugSepOctNovDeccoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan21Refreshing
Feb21Refreshing
Mar22Refreshing
Apr24Refreshing
May25Warm
Jun27Warm
Jul28Tropical
Aug28Tropical
Sep27Warm
Oct26Warm
Nov24Warm
Dec23Refreshing

UV index in Keelung in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 11 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Keelung peaks around June 18 at about 11 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 22 at about 4 (moderate).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecVery highExtremeVery highVery highHighJun 18UV 11Dec 22UV 4
UV index (midday)Level
Jan5Moderate
Feb7Very high
Mar9Very high
Apr8Very high
May10Extreme
Jun12Extreme
Jul11Extreme
Aug9Very high
Sep11Extreme
Oct8Very high
Nov7High
Dec4Moderate

Air quality in Keelung 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 Keelung is worst in April — around 47 µg/m³ PM2.5 (poor), about 2.3× the cleanest month (October, 20 µg/m³).

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

0204060JanFebMarAprMayJunJulAugSepOctNovDecModeratePoorModerateApr 1447 µg/m³Oct 1521 µg/m³
PM2.5 (µg/m³)Level
Jan29Moderate
Feb36Poor
Mar44Poor
Apr47Poor
May42Poor
Jun42Poor
Jul34Moderate
Aug28Moderate
Sep24Moderate
Oct20Moderate
Nov25Moderate
Dec25Moderate
Location & terrain

Where is Keelung?

Keelung sits at 25.1°N, 121.7°E, 19 m above sea level, in Taiwan. The nearest listed city is Jiufen, 11 km away.

TaipeiSanzhiNew Taipei CityDanshuiBanqiao

Topography around Keelung

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

Within 3 km, the terrain around Keelung has only modest variations in elevation — a maximum elevation change of 197 m around an average of 58 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 907 m; within 80 km, extreme variations in elevation — a maximum elevation change of 2,613 m.

The land around Keelung is covered by trees (58%) and artificial surfaces (32%) within 3 km, trees (59%) and water (35%) within 16 km, and water (62%) and trees (31%) within 80 km.

3 km
197 m
16 km
907 m
80 km
2,613 m
treesgrasslandcroplandartificial surfaceswater
September weather nearby: Jiufen 11 km · Xizhi 11 km · Neihu 16 km · Taipei 23 km · Sanzhi 28 km · New Taipei City 30 km · Danshui 30 km · Banqiao 30 km

Taiwan travel facts

Travel advisory
Level 1
Exercise Normal Precautions
Power plugs
Type A / B
110 / 220 V · 60 Hz
Happiness
6.7 / 10
World Happiness, 2025
Religion
Buddhist 35%Taoist 33%none or unspecified 18%folk religion approximately 10%

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 Keelung (25.1309°, 121.7409°, elevation 19 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).