Montero weather in September

In September, Montero sees average daytime highs of 30°C and overnight lows near 20°C, with 96 mm of rain across 8.4 wet days and about 11.9 hours of daylight. It is the 3rd-warmest and 7th-wettest month of the year here.

Day-to-day highs hold fairly steady near 30°C through the month. The sky is clear or mostly clear about 43% of the time in September, and the air most often feels oppressive.

Daylight stretches from about 11 h 42 min at the start of September to 12 h 06 min by month's end. Set against the rest of the year, September is Montero's 3rd-clearest and 1st-windiest month. For the whole year in context, see Montero's year-round climate.

Daytime high
30°
3rd warmest
Overnight low
20°
5th coldest
Rainfall
96 mm
8.4 wet days
Daylight
11 h 54 min
6:10 AM – 6:04 PM
Cloud cover
52%
3rd clearest
Wind
12 km/h
1st windiest
Solar energy
5.27 kWh/m²
Travel score
5.0
out of 10

Montero is city in Bolivia.

Density
316/km²
people per km²
Founded
1854

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 30°C through the month.

A typical September day in Montero reaches about 30°C in the afternoon and slips back to 20°C overnight — a 11°C spread between the day's warmth and the night's chill. On most days the high lands between 24°C and 35°C. Set against its neighbours, September runs about 2°C warmer than August and on par with October.

10°20°30°40°151015202530
Avg high (°C)Avg low (°C)
13019
23019
33019
43019
53019
63019
73019
83020
93020
103020
113020
123020
133020
143020
153020
163120
173120
183120
193120
203120
213120
223120
233120
243120
253121
263121
273121
283121
293121
303121

How September really feels in Montero

Once humidity and wind are folded in, September averages 2 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
2
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.

Montero weather by month

How September compares with the rest of the year at a glance. September is the 3rd-warmest and 7th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan30° / 23°23222.612.93.3
Feb30° / 23°20620.912.63.4
Mar30° / 22°15519.612.13.8
Apr29° / 21°961411.64.9
May26° / 18°821211.26.3
Jun25° / 17°619.9116.7
Jul26° / 16°466.611.17.4
Aug28° / 18°505.811.46.6
Sep30° / 20°968.411.95.0
Oct31° / 22°13714.612.44.0
Nov31° / 22°17217.112.83.7
Dec30° / 23°23923.3133.2

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 43% of the time in September.

Beyond those clear spells, partly cloudy skies cover about 17% of September, with mostly cloudy or overcast conditions the remaining 40%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
17030
27030
36931
46931
56832
66832
76733
86634
96634
106535
116436
126337
136337
146238
156139
166040
175941
185941
195842
205644
215644
225545
235347
245248
255248
265149
275050
285050
294951
305050

Chance of precipitation in September

Any precipitation

Montero gets around 96 mm of rain over 8.4 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 29% and peaks near 36% on the wettest days. The odds climb toward the end of the month.

0%10%20%30%40%50%151015202530
Rain chance (%)
122
223
324
425
525
626
726
827
927
1027
1127
1227
1328
1428
1528
1628
1728
1828
1928
2028
2129
2229
2330
2431
2532
2633
2734
2835
2936
3036

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 27% of days. Sticky, muggy-or-worse air turns up on roughly 52% of them.

0%25%50%75%100%151015202530
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
12510172920
22410172820
32410172821
42411172721
52411182622
62411182622
72312182522
82312182522
92312192522
102212192522
112212192522
122113192522
132113192523
142012182623
152012182524
162012182525
172012182525
181912182526
191911182527
201811182528
211811182529
221711172530
231611172531
241510172532
251410162534
261410162535
271310162536
281210152537
291110152538
301110152539

Wind in September

Winds average 12 km/h in September, the windiest month of the year.

Across September, daily wind ranges from about 12 km/h on the calmest days to 12 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202530
Wind speed (km/h)Feels
112light breeze
212light breeze
312light breeze
412light breeze
512light breeze
612light breeze
712light breeze
812light breeze
912light breeze
1012light breeze
1112light breeze
1212light breeze
1312light breeze
1412light breeze
1512light breeze
1612light breeze
1712light breeze
1812light breeze
1912light breeze
2012light breeze
2112light breeze
2212light breeze
2312light breeze
2412light breeze
2512light breeze
2612light breeze
2712light breeze
2812light breeze
2912light breeze
3012light breeze

Sunrise & sunset in September

DaylightNight

Daylight runs from about 11 h 42 min at the start of September to 12 h 06 min by month's end. The lit band spans sunrise to sunset each day.

Days grow by about 24 minutes over September. Sunrise moves from 6:23 AM to 5:58 AM, and sunset from 6:02 PM to 6:06 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
111.76:236:02
211.76:226:03
311.76:216:03
411.76:216:03
511.76:206:03
611.76:196:03
711.86:186:03
811.86:176:03
911.86:166:04
1011.86:156:04
1111.86:156:04
1211.86:146:04
1311.96:136:04
1411.96:126:04
1511.96:116:04
1611.96:106:04
1711.96:096:05
1811.96:086:05
1912.06:086:05
2012.06:076:05
2112.06:066:05
2212.06:056:05
2312.06:046:05
2412.06:036:06
2512.16:026:06
2612.16:026:06
2712.16:016:06
2812.16:006:06
2912.15:596:06
3012.15:586:06

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 5.27 kWh/m².

For context, solar energy here swings from a low near 3.26 kWh/m² to a high of 5.42 kWh/m² in October across the year — September's 5.27 kWh/m² falls in the middle.

0246151015202530
Solar energy (kWh/m²)Level
15.0Bright
25.0Bright
35.1Bright
45.1Bright
55.1Bright
65.1Bright
75.1Bright
85.2Bright
95.2Bright
105.2Bright
115.2Bright
125.2Bright
135.2Bright
145.3Bright
155.3Bright
165.3Bright
175.3Bright
185.3Bright
195.3Bright
205.3Bright
215.3Bright
225.3Bright
235.4Bright
245.4Bright
255.4Bright
265.3Bright
275.3Bright
285.3Bright
295.3Bright
305.4Bright
Planning a trip in September

Hazard calendar for Montero

In seasonPeak

None of Montero's seasonal hazards are active in September. The full-year calendar below shows when the rainy season, cyclone risk and dust haze do peak.

Montero's rainy season runs October–March, when most of the year's rain falls.

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

Is September a good time to visit Montero?

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

5.0
Sightseeing
5th-best month of the year
7.1
Beach & pool
2nd-best month of the year

September is a reasonable time to visit Montero for sightseeing. The water and warmth also suit a beach or pool day.

What to pack for Montero in September

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

In September, Montero sees daytime highs around 30°C and nights near 20°C. Pack light clothes. Worth having: rain gear and sun protection. About 8 days see rain.

light clothesrain gearsun protection

UV index in Montero 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 Montero peaks around January 18 at about 15 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near July 15 at about 7 (very high).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highExtremeJan 18UV 15Jul 15UV 7
UV index (midday)Level
Jan15Extreme
Feb14Extreme
Mar14Extreme
Apr11Extreme
May9Very high
Jun7Very high
Jul7High
Aug8Very high
Sep9Very high
Oct8Very high
Nov13Extreme
Dec14Extreme

Air quality in Montero 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 Montero is worst in September — around 52 µg/m³ PM2.5 (poor), about 6.7× the cleanest month (May, 8 µg/m³).

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

0204060JanFebMarAprMayJunJulAugSepOctNovDecGoodModeratePoorModerateSep 1749 µg/m³May 118 µg/m³
PM2.5 (µg/m³)Level
Jan10Good
Feb11Good
Mar10Good
Apr8Good
May8Good
Jun10Good
Jul14Moderate
Aug29Moderate
Sep52Poor
Oct33Moderate
Nov17Moderate
Dec10Good
Location & terrain

Where is Montero?

Montero sits at 17.3°S, 63.3°W, 300 m above sea level, in Bolivia. The nearest listed city is Warnes, 22 km away.

Ascención de GuarayosMizqueSan Ignacio de Velasco

Topography around Montero

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

Within 3 km, the terrain around Montero has only modest variations in elevation — a maximum elevation change of 19 m around an average of 291 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 84 m; within 80 km, very significant variations in elevation — a maximum elevation change of 1,536 m.

The land around Montero is covered by artificial surfaces (52%) and trees (21%) within 3 km, grassland (44%), trees (26%) and cropland (23%) within 16 km, and trees (37%), cropland (34%) and grassland (25%) within 80 km.

3 km
19 m
16 km
84 m
80 km
1,536 m
treesshrubsgrasslandcroplandartificial surfacesbare terrainwater
September weather nearby: Warnes 22 km · Santa Cruz 50 km · Cotoca 57 km · Villa Yapacaní 62 km · El Torno 75 km · Ascención de Guarayos 161 km · Mizque 231 km · San Ignacio de Velasco 266 km

Bolivia travel facts

Travel advisory
Level 2
Exercise Increased Caution
Power plugs
Type A / B / C
230 V · 50 Hz
Prices
≈ 40% of US
price level, 2025
GDP per capita
$5,148
2025
Happiness
5.8 / 10
World Happiness, 2025
Homicide rate
4.4
per 100k, 2023
Road deaths
21.1
per 100k/yr, 2019
Income group
Lower middle
World Bank
English
Moderate
EF EPI 521
Religion
Roman Catholic 65%Protestant 20%none 6%other 5%

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 Montero (-17.3387°, -63.2509°, elevation 300 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).