Jiufen weather in September

In September, Jiufen sees average daytime highs of 28°C and overnight lows near 25°C, with 257 mm of rain across 17.8 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 29°C in the first days to 27°C by the end. The sky is clear or mostly clear about 23% of the time in September, and the air most often feels oppressive.

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 Jiufen's 2nd-clearest and 6th-windiest month. For the whole year in context, see Jiufen's year-round climate.

Daytime high
28°
4th warmest
Overnight low
25°
9th coldest
Rainfall
257 mm
17.8 wet days
Daylight
12 h 06 min
5:43 AM – 5:51 PM
Cloud cover
65%
2nd clearest
Wind
13 km/h
6th windiest
Solar energy
4.63 kWh/m²
Travel score
4.9
out of 10

Jiufen is mountain area in Ruifang District near Keelung, Taiwan.

Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 29°C in the first days to 27°C by the end.

A typical September day in Jiufen reaches about 28°C in the afternoon and slips back to 25°C overnight — a 3°C spread between the day's warmth and the night's chill. On most days the high lands between 26°C and 30°C. Set against its neighbours, September runs about 2°C cooler than August and about 3°C warmer than October.

20°25°30°35°151015202530
Avg high (°C)Avg low (°C)
12926
22926
32926
42926
52926
62926
72926
82926
92926
102825
112825
122825
132825
142825
152825
162825
172825
182825
192825
202725
212725
222724
232724
242724
252724
262724
272724
282724
292724
302724

How September really feels in Jiufen

Once humidity and wind are folded in, September averages 12 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
12
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.

Jiufen 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
Jan17° / 14°17420.110.64.1
Feb18° / 15°16017.711.14.4
Mar20° / 16°1371711.85.1
Apr23° / 19°12815.512.65.7
May26° / 22°18517.613.25.4
Jun29° / 25°16316.313.54.5
Jul30° / 27°1541413.44.4
Aug30° / 27°22317.612.94.2
Sep28° / 25°25717.812.24.9
Oct25° / 22°31319.311.45.3
Nov22° / 20°27819.210.85.1
Dec19° / 16°22719.510.54.6

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 23% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 20% of September, with mostly cloudy or overcast conditions the remaining 57%.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
14258
24159
34258
44258
54258
64258
74258
84258
94357
104357
114456
124654
134555
144555
154555
164456
174456
184555
194456
204357
214258
224258
234258
244258
254159
264159
274159
284060
294060
304060

Chance of precipitation in September

Any precipitation

Jiufen gets around 257 mm of rain over 17.8 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 59% and peaks near 63% on the wettest days.

0%20%40%60%151015202530
Rain chance (%)
160
260
360
460
560
660
760
859
959
1058
1158
1258
1357
1457
1557
1658
1758
1858
1958
2058
2159
2259
2359
2459
2559
2660
2761
2861
2962
3063

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, September lands in the oppressive band about 43% 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 (%)
10033166
20043363
30043561
40053758
50063856
60063955
70174052
80184150
90194149
1002104247
1102114245
1203124243
1304134241
1404144339
1505154337
1605164335
1706174333
1807184431
1907194529
2008204527
2108204625
2218214723
2319214821
2419224820
2519224919
26110234917
27110234916
28110235115
29211235014
30211235014

Wind in September

Winds average 13 km/h in September.

Across September, daily wind ranges from about 10 km/h on the calmest days to 15 km/h at its breeziest. It stays fairly steady from day to day.

05101520151015202530
Wind speed (km/h)Feels
110calm
211calm
311calm
411calm
511calm
611calm
711calm
811calm
912calm
1012calm
1112light breeze
1212light breeze
1312light breeze
1413light breeze
1513light breeze
1613light breeze
1713light breeze
1813light breeze
1914light breeze
2014light breeze
2114light breeze
2214light breeze
2314light breeze
2414light breeze
2514light breeze
2614light breeze
2714light breeze
2815light breeze
2915light breeze
3015light breeze

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 5:48 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
212.55:376:07
312.55:386:06
412.45:386:05
512.45:386:04
612.45:396:02
712.45:396:01
812.35:406:00
912.35:405:59
1012.35:405:58
1112.35:415:57
1212.25:415:56
1312.25:415:55
1412.25:425:54
1512.25:425:52
1612.15:435:51
1712.15:435:50
1812.15:435:49
1912.15:445:48
2012.05:445:47
2112.05:455:46
2212.05:455:45
2312.05:455:43
2411.95:465:42
2511.95:465:41
2611.95:475:40
2711.95:475:39
2811.85:475:38
2911.85:485:37
3011.85:485:36

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.63 kWh/m².

For context, solar energy here swings from a low near 2.02 kWh/m² to a high of 5.9 kWh/m² in July across the year — September's 4.63 kWh/m² falls in the middle.

0246151015202530
Solar energy (kWh/m²)Level
15.1Bright
25.1Bright
35.0Bright
45.0Bright
55.0Bright
65.0Bright
75.0Bright
84.9Bright
94.9Bright
104.9Bright
114.8Bright
124.8Bright
134.8Bright
144.7Bright
154.7Bright
164.7Bright
174.6Bright
184.6Bright
194.5Bright
204.5Bright
214.4Bright
224.4Bright
234.3Bright
244.3Bright
254.3Bright
264.2Bright
274.2Bright
284.1Bright
294.1Bright
304.0Bright
Planning a trip in September

Hazard calendar for Jiufen

In seasonPeak

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

Jiufen 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 Jiufen?

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

4.9
Sightseeing
6th-best month of the year
5.5
Beach & pool
4th-best month of the year

September is a reasonable time to visit Jiufen for sightseeing.

What to pack for Jiufen in September

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

In September, Jiufen sees daytime highs around 28°C and nights near 25°C. Pack light clothes and rain gear. Worth having: sun protection. About 18 days see rain.

light clothesrain gearsun protection

Sea temperature near Jiufen 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 offshore 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 Jiufen 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 Jiufen peaks around July 13 at about 12 (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.

025710JanFebMarAprMayJunJulAugSepOctNovDecHighVery highExtremeVery highHighJul 13UV 12Dec 22UV 4
UV index (midday)Level
Jan5Moderate
Feb7Very high
Mar9Very high
Apr8Very high
May10Extreme
Jun11Extreme
Jul12Extreme
Aug11Extreme
Sep11Extreme
Oct8Very high
Nov7High
Dec4Moderate

Air quality in Jiufen 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 Jiufen is worst in April — around 52 µg/m³ PM2.5 (poor), about 2.1× the cleanest month (October, 25 µg/m³).

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

0204060JanFebMarAprMayJunJulAugSepOctNovDecPoorModerateApr 1052 µg/m³Oct 1626 µg/m³
PM2.5 (µg/m³)Level
Jan38Poor
Feb43Poor
Mar51Poor
Apr52Poor
May44Poor
Jun41Poor
Jul32Moderate
Aug32Moderate
Sep30Moderate
Oct25Moderate
Nov32Moderate
Dec32Moderate
Location & terrain

Where is Jiufen?

Jiufen sits at 25.1°N, 121.8°E, 0 m above sea level, in Taiwan. The nearest listed city is Keelung, 11 km away.

NeihuTaipeiSanzhiNew Taipei CityBanqiaoYilan

Topography around Jiufen

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

Within 3 km, the terrain around Jiufen has large variations in elevation — a maximum elevation change of 710 m around an average of 221 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 752 m; within 80 km, extreme variations in elevation — a maximum elevation change of 2,425 m.

The land around Jiufen is covered by trees (77%) within 3 km, trees (48%) and water (48%) within 16 km, and water (64%) and trees (29%) within 80 km.

3 km
710 m
16 km
752 m
80 km
2,425 m
treescroplandartificial surfaceswater
September weather nearby: Keelung 11 km · Xizhi 19 km · Neihu 26 km · Taipei 33 km · Sanzhi 38 km · New Taipei City 39 km · Banqiao 39 km · Yilan 40 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 Jiufen (25.1096°, 121.8442°, 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).