Siddharthanagar weather in September

In September, Siddharthanagar sees average daytime highs of 31°C and overnight lows near 25°C, with 188 mm of rain across 22.1 wet days and about 12.2 hours of daylight. It is the 6th-warmest and 4th-wettest month of the year here.

Day-to-day highs hold fairly steady near 31°C through the month. The sky is clear or mostly clear about 33% of the time in September, and the air most often feels miserable.

Daylight stretches from about 12 h 36 min at the start of September to 11 h 48 min by month's end. Set against the rest of the year, September is Siddharthanagar's 10th-clearest and 8th-windiest month. For the whole year in context, see Siddharthanagar's year-round climate.

Daytime high
31°
6th warmest
Overnight low
25°
9th coldest
Rainfall
188 mm
22.1 wet days
Daylight
12 h 12 min
6:01 AM – 6:10 PM
Cloud cover
59%
10th clearest
Wind
6 km/h
8th windiest
Solar energy
4.23 kWh/m²
Travel score
3.2
out of 10

Siddharthanagar is city in western Nepal.

Density
1,759/km²
people per km²
Founded
1967

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

Temperature in September

Average highAverage lowShaded bands: 10–90% of days

Day-to-day highs hold fairly steady near 31°C through the month.

A typical September day in Siddharthanagar reaches about 31°C in the afternoon and slips back to 25°C overnight — a 6°C spread between the day's warmth and the night's chill. On most days the high lands between 29°C and 33°C. Set against its neighbours, September runs on par with August and about 1°C warmer than October.

20°25°30°35°151015202530
Avg high (°C)Avg low (°C)
13226
23226
33226
43226
53226
63226
73226
83226
93225
103125
113125
123125
133125
143125
153125
163125
173125
183125
193125
203125
213125
223125
233124
243124
253124
263124
273124
283124
293124
303124

How September really feels in Siddharthanagar

Once humidity and wind are folded in, September averages 30 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
30
15 feel dangerously hot (≥ 39°C)
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.

Siddharthanagar weather by month

How September compares with the rest of the year at a glance. September is the 6th-warmest and 4th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan21° / 192.410.58.1
Feb25° / 12°192.5118.5
Mar31° / 16°122.211.86.1
Apr35° / 21°153.612.62.9
May36° / 24°499.413.32.3
Jun34° / 26°25019.613.72.3
Jul32° / 26°3952813.62.3
Aug32° / 26°34627.3132.4
Sep31° / 25°18822.112.23.2
Oct30° / 21°375.411.35.8
Nov27° / 15°40.610.68.4
Dec23° / 11°90.910.38.9

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 33% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 18% of September, with mostly cloudy or overcast conditions the remaining 49%. Skies tend to open up as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
12773
22971
33070
43169
53367
63466
73664
83862
93862
104060
114258
124456
134555
144753
154753
164951
175149
185347
195644
205743
216040
226238
236436
246733
256931
267129
277327
287525
297723
307921

Chance of precipitation in September

Any precipitation

Siddharthanagar gets around 188 mm of rain over 22.1 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 73% and peaks near 84% on the wettest days. The odds ease toward the end of the month.

0%20%40%60%80%151015202530
Rain chance (%)
184
284
383
483
583
683
782
882
981
1081
1180
1279
1379
1478
1577
1676
1775
1874
1973
2071
2169
2267
2365
2463
2561
2659
2756
2854
2951
3049

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 82% of days. Sticky, muggy-or-worse air turns up on roughly 100% of them.

0%25%50%75%100%151015202530
Muggy (%)Oppressive (%)Miserable (%)
10397
20496
30496
40496
50595
60595
70595
80694
90694
100793
110892
120892
130991
1401090
1501189
1601288
1701486
1801684
1901783
2011980
2112277
2212475
2312673
2422969
2523266
2623464
2733760
2834057
2944353
3054649

Wind in September

Winds average 6 km/h in September.

Across September, daily wind ranges from about 5 km/h on the calmest days to 6 km/h at its breeziest. It stays fairly steady from day to day.

0246810151015202530
Wind speed (km/h)Feels
16calm
26calm
36calm
46calm
56calm
66calm
76calm
86calm
96calm
106calm
116calm
126calm
136calm
146calm
156calm
166calm
176calm
186calm
196calm
205calm
215calm
225calm
235calm
245calm
255calm
265calm
275calm
285calm
295calm
305calm

Sunrise & sunset in September

DaylightNight

Daylight runs from about 12 h 36 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 48 minutes over September. Sunrise moves from 5:54 AM to 6:07 AM, and sunset from 6:28 PM to 5:54 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.65:546:28
212.55:546:27
312.55:556:26
412.55:556:25
512.55:566:23
612.45:566:22
712.45:576:21
812.45:576:20
912.45:576:19
1012.35:586:18
1112.35:586:16
1212.35:596:15
1312.25:596:14
1412.26:006:13
1512.26:006:12
1612.26:016:10
1712.16:016:09
1812.16:026:08
1912.16:026:07
2012.06:036:06
2112.06:036:04
2212.06:046:03
2312.06:046:02
2411.96:046:01
2511.96:055:59
2611.96:055:58
2711.96:065:57
2811.86:065:56
2911.86:075:55
3011.86:075:54

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 4.23 kWh/m².

For context, solar energy here swings from a low near 3.66 kWh/m² to a high of 6.65 kWh/m² in April across the year — September's 4.23 kWh/m² falls in the middle.

012345151015202530
Solar energy (kWh/m²)Level
14.2Bright
24.2Bright
34.2Bright
44.2Bright
54.2Bright
64.2Bright
74.2Bright
84.2Bright
94.2Bright
104.2Bright
114.2Bright
124.2Bright
134.2Bright
144.2Bright
154.2Bright
164.2Bright
174.2Bright
184.2Bright
194.2Bright
204.2Bright
214.3Bright
224.3Bright
234.3Bright
244.3Bright
254.3Bright
264.3Bright
274.4Bright
284.4Bright
294.4Bright
304.4Bright
Planning a trip in September

Hazard calendar for Siddharthanagar

In seasonPeak

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

Siddharthanagar's monsoon runs June–September, when most of the year's rain falls.

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

Is September a good time to visit Siddharthanagar?

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

3.2
Sightseeing
7th-best month of the year
4.8
Beach & pool
9th-best month of the year

September is a weaker month for outdoor sightseeing in Siddharthanagar.

What to pack for Siddharthanagar in September

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

In September, Siddharthanagar sees daytime highs around 31°C and nights near 25°C. Pack light clothes and rain gear. About 22 days see rain.

light clothesrain gear

UV index in Siddharthanagar in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 9 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Siddharthanagar peaks around July 22 at about 10 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near November 22 at about 4 (moderate).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateVery highExtremeVery highModerateJul 22UV 10Nov 22UV 4
UV index (midday)Level
Jan4Moderate
Feb4Moderate
Mar8Very high
Apr8Very high
May9Very high
Jun8Very high
Jul11Extreme
Aug10Extreme
Sep9Very high
Oct6High
Nov4Moderate
Dec4Moderate

Air quality in Siddharthanagar 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 Siddharthanagar is worst in January — around 166 µg/m³ PM2.5 (very unhealthy), about 4.5× the cleanest month (July, 37 µg/m³).

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

0306090120150180JanFebMarAprMayJunJulAugSepOctNovDecVery unhealthyUnhealthyPoorUnhealthyVery unhealthyJan 12164 µg/m³Jul 2139 µg/m³
PM2.5 (µg/m³)Level
Jan166Very unhealthy
Feb138Unhealthy
Mar104Unhealthy
Apr90Unhealthy
May69Unhealthy
Jun63Unhealthy
Jul37Poor
Aug44Poor
Sep54Poor
Oct95Unhealthy
Nov140Unhealthy
Dec158Very unhealthy
Location & terrain

Where is Siddharthanagar?

Siddharthanagar sits at 27.5°N, 83.5°E, 107 m above sea level, in Nepal. The nearest listed city is Lumbini, 20 km away.

WāliṅBāgluṅChitwanPokharaTulsi̇̄pur

Topography around Siddharthanagar

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

Within 3 km, the terrain around Siddharthanagar has only modest variations in elevation — a maximum elevation change of 20 m around an average of 105 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 62 m; within 80 km, extreme variations in elevation — a maximum elevation change of 2,677 m.

The land around Siddharthanagar is covered by cropland (58%) and artificial surfaces (25%) within 3 km, cropland (80%) within 16 km, and cropland (49%) and trees (46%) within 80 km.

3 km
20 m
16 km
62 m
80 km
2,677 m
treesgrasslandcroplandartificial surfacesbare terrainwater
September weather nearby: Lumbini 20 km · Butwāl 21 km · Tānsen 42 km · Wāliṅ 62 km · Bāgluṅ 87 km · Chitwan 99 km · Pokhara 99 km · Tulsi̇̄pur 133 km

Nepal travel facts

Travel advisory
Level 2
Exercise Increased Caution
Power plugs
Type C / D / M
230 V · 50 Hz
Prices
≈ 24% of US
price level, 2025
GDP per capita
$1,536
2025
Happiness
5.1 / 10
World Happiness, 2025
Safe drinking water
16%
of population, 2024
Homicide rate
2.1
per 100k, 2020
Road deaths
16.3
per 100k/yr, 2019
Income group
Lower middle
World Bank
English
Moderate
EF EPI 514
Religion
Hindu 81%Buddhist 8%Muslim 5%Kirat 3%

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 Siddharthanagar (27.5°, 83.45°, elevation 107 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. 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).