Mossoró weather in September

In September, Mossoró sees average daytime highs of 35°C and overnight lows near 23°C, with 1 mm of rain across 0.2 wet days and about 12 hours of daylight. It is the 2nd-warmest and 12th-wettest month of the year here.

Day-to-day highs hold fairly steady near 35°C through the month. The sky is clear or mostly clear about 66% of the time in September, and the air most often feels humid.

Daylight stretches from about 11 h 54 min at the start of September to 12 hours by month's end. Set against the rest of the year, September is Mossoró's 1st-clearest and 2nd-windiest month. For the whole year in context, see Mossoró's year-round climate.

Daytime high
35°
2nd warmest
Overnight low
23°
4th coldest
Rainfall
1 mm
0.2 wet days
Daylight
12 hours
5:25 AM – 5:23 PM
Cloud cover
33%
1st clearest
Wind
18 km/h
2nd windiest
Solar energy
6.57 kWh/m²
Travel score
3.3
out of 10

Mossoró is human settlement in Brazil.

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 35°C through the month.

A typical September day in Mossoró reaches about 35°C in the afternoon and slips back to 23°C overnight — a 12°C spread between the day's warmth and the night's chill. On most days the high lands between 34°C and 36°C. Set against its neighbours, September runs about 1°C warmer than August and on par with October.

20°25°30°35°40°151015202530
Avg high (°C)Avg low (°C)
13523
23523
33523
43523
53523
63523
73523
83523
93523
103523
113523
123523
133523
143523
153523
163523
173523
183523
193523
203523
213523
223523
233523
243523
253523
263523
273523
283523
293523
303523

How September really feels in Mossoró

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
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.

Mossoró weather by month

How September compares with the rest of the year at a glance. September is the 2nd-warmest and 12th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan34° / 24°681212.33.0
Feb33° / 24°8313.312.23.1
Mar32° / 24°12718.3123.1
Apr32° / 24°11716.811.93.3
May33° / 24°56911.83.8
Jun32° / 23°295.911.74.2
Jul33° / 22°18311.74.2
Aug34° / 22°30.511.83.7
Sep35° / 23°10.2123.3
Oct35° / 23°20.212.13.1
Nov35° / 24°30.512.23.2
Dec35° / 24°164.212.33.2

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 66% of the time in September, the clearest month of the year.

Beyond those clear spells, partly cloudy skies cover about 22% of September, with mostly cloudy or overcast conditions the remaining 12%. Skies tend to open up as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
18416
28515
38515
48515
58515
68515
78515
88515
98515
108515
118515
128515
138614
148713
158713
168812
178812
188911
19919
20919
21928
22928
23937
24937
25928
26928
27928
28919
29919
30919

Chance of precipitation in September

Any precipitation

Mossoró gets around 1 mm of rain over 0.2 wet days in September, the driest month. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 1% and peaks near 1% on the wettest days.

0%10%20%30%151015202530
Rain chance (%)
11
21
31
41
51
61
71
81
91
101
111
121
131
141
151
161
171
181
191
201
211
221
230
240
250
260
270
280
290
300

Humidity in September

DryComfortableHumidMuggyOppressiveMiserable

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

By dew point, September lands in the humid band about 54% of days. Sticky, muggy-or-worse air turns up on roughly 45% of them.

0%25%50%75%100%151015202530
Comfortable (%)Humid (%)Muggy (%)Oppressive (%)
1360361
2360361
3360361
4360361
5360361
6360361
7361360
8360370
9359380
10359380
11358390
12357400
13257410
14256420
15254431
16253441
17252451
18251461
19250471
20151471
21149481
22149491
23148492
24148502
25147502
26146512
27145522
28145522
29144523
30143533

Wind in September

Winds average 18 km/h in September.

Across September, daily wind ranges from about 18 km/h on the calmest days to 19 km/h at its breeziest. It stays fairly steady from day to day.

0510152025151015202530
Wind speed (km/h)Feels
118light breeze
218light breeze
318light breeze
418light breeze
518light breeze
618light breeze
718light 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
2418light breeze
2518light breeze
2618light breeze
2718light breeze
2818light breeze
2919light breeze
3019light breeze

Sunrise & sunset in September

DaylightNight

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

Days grow by about 6 minutes over September. Sunrise moves from 5:32 AM to 5:17 AM, and sunset from 5:26 PM to 5:20 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
111.95:325:26
211.95:325:26
311.95:315:26
411.95:315:25
511.95:305:25
611.95:305:25
711.95:295:25
811.95:295:25
911.95:285:24
1011.95:285:24
1111.95:275:24
1212.05:275:24
1312.05:265:24
1412.05:265:23
1512.05:255:23
1612.05:255:23
1712.05:245:23
1812.05:245:22
1912.05:235:22
2012.05:225:22
2112.05:225:22
2212.05:215:22
2312.05:215:21
2412.05:205:21
2512.05:205:21
2612.05:195:21
2712.05:195:20
2812.05:185:20
2912.05:185:20
3012.05:175:20

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 6.57 kWh/m².

For context, solar energy here swings from a low near 4.79 kWh/m² to a high of 6.83 kWh/m² in October across the year — September's 6.57 kWh/m² sits near the top of that range.

0246151015202530
Solar energy (kWh/m²)Level
16.2Intense
26.3Intense
36.3Intense
46.3Intense
56.3Intense
66.3Intense
76.3Intense
86.4Intense
96.4Intense
106.4Intense
116.4Intense
126.5Intense
136.5Intense
146.5Intense
156.5Intense
166.6Intense
176.6Intense
186.6Intense
196.7Intense
206.7Intense
216.7Intense
226.7Intense
236.8Intense
246.8Intense
256.8Intense
266.8Intense
276.8Intense
286.8Intense
296.9Intense
306.9Intense
Planning a trip in September

Hazard calendar for Mossoró

In seasonPeak

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

Mossoró's rainy season runs January–April, 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 Mossoró?

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

3.3
Sightseeing
5th-best month of the year
7.1
Beach & pool
3rd-best month of the year

September is a weaker month for outdoor sightseeing in Mossoró. The water and warmth also suit a beach or pool day.

What to pack for Mossoró in September

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

In September, Mossoró sees daytime highs around 35°C and nights near 23°C. Pack light clothes and sun protection.

light clothessun protection

Sea temperature near Mossoró 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 42 km away) is warmest in April at about 29°C and coldest in August near 26°C.

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

24°26°28°30°JanFebMarAprMayJunJulAugSepOctNovDecwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan28Tropical
Feb29Tropical
Mar29Tropical
Apr29Tropical
May29Tropical
Jun28Warm
Jul27Warm
Aug26Warm
Sep27Warm
Oct27Warm
Nov28Warm
Dec28Tropical

UV index in Mossoró in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 12 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Mossoró peaks around March 15 at about 15 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near July 13 at about 10 (very high).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highExtremeMar 15UV 15Jul 13UV 10
UV index (midday)Level
Jan13Extreme
Feb14Extreme
Mar15Extreme
Apr14Extreme
May11Extreme
Jun10Very high
Jul10Very high
Aug10Extreme
Sep12Extreme
Oct12Extreme
Nov12Extreme
Dec11Extreme
Location & terrain

Where is Mossoró?

Mossoró sits at 5.2°S, 37.3°W, 24 m above sea level, in Brazil. The nearest listed city is Baraúna, 32 km away.

Topography around Mossoró

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

Within 3 km, the terrain around Mossoró has only modest variations in elevation — a maximum elevation change of 44 m around an average of 17 m above sea level; within 16 km, only modest variations in elevation — a maximum elevation change of 140 m; within 80 km, significant variations in elevation — a maximum elevation change of 432 m.

The land around Mossoró is covered by artificial surfaces (60%) and grassland (24%) within 3 km, shrubs (57%) and grassland (26%) within 16 km, and shrubs (50%), grassland (21%) and water (20%) within 80 km.

3 km
44 m
16 km
140 m
80 km
432 m
treesshrubsgrasslandcroplandartificial surfacesbare terrainwaterwetland
September weather nearby: Baraúna 32 km · Areia Branca 34 km · Icapuí 53 km · Jaguaruana 62 km · Açu 65 km · Caraúbas 71 km · Quixeré 72 km · Apodi 73 km

Brazil travel facts

Travel advisory
Level 2
Exercise Increased Caution
Power plugs
Type C / N
127 / 220 V · 60 Hz
Prices
≈ 46% of US
price level, 2025
GDP per capita
$10,713
2025
Happiness
6.6 / 10
World Happiness, 2025
Safe drinking water
89%
of population, 2024
Homicide rate
19.3
per 100k, 2023
Road deaths
16
per 100k/yr, 2019
Income group
Upper middle
World Bank
English
Low
EF EPI 482
Religion
Roman Catholic 57%Evangelical 27%none 9%other 4%

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 Mossoró (-5.1875°, -37.3442°, elevation 24 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. 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. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).