San Fernando weather in September

In September, San Fernando sees average daytime highs of 29°C and overnight lows near 26°C, with 123 mm of rain across 22.4 wet days and about 12.1 hours of daylight. It is the 2nd-warmest and 6th-wettest month of the year here.

Day-to-day highs hold fairly steady near 29°C through the month. The sky is clear or mostly clear about 22% of the time in September, and the air most often feels miserable.

Daylight stretches from about 12 h 12 min at the start of September to 11 h 54 min by month's end. Set against the rest of the year, September is San Fernando's 7th-clearest and 11th-windiest month. For the whole year in context, see San Fernando's year-round climate.

Daytime high
29°
2nd warmest
Overnight low
26°
12th coldest
Rainfall
123 mm
22.4 wet days
Daylight
12 h 06 min
5:59 AM – 6:02 PM
Cloud cover
66%
7th clearest
Wind
14 km/h
11th windiest
Solar energy
5.71 kWh/m²
Travel score
3.8
out of 10

San Fernando is city in Trinidad and Tobago.

Density
2,973/km²
people per km²
Founded
1595

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 29°C through the month.

A typical September day in San Fernando reaches about 29°C in the afternoon and slips back to 26°C overnight — a 3°C spread between the day's warmth and the night's chill. On most days the high lands between 28°C and 30°C. Set against its neighbours, September runs on par with August and on par with October.

20°23°25°28°30°151015202530
Avg high (°C)Avg low (°C)
12925
22925
32925
42925
52925
62926
72926
82926
92926
102926
112926
122926
132926
142926
152926
162926
172926
182926
192926
202926
212926
222926
232926
242926
252926
262926
272926
282926
292926
302926

How September really feels in San Fernando

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.

San Fernando weather by month

How September compares with the rest of the year at a glance. September is the 2nd-warmest and 6th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan28° / 24°399.111.56.7
Feb28° / 24°185.411.77.0
Mar28° / 24°22511.96.5
Apr29° / 25°28612.25.9
May29° / 25°6112.312.55.1
Jun28° / 25°13821.812.64.1
Jul28° / 25°15226.312.53.7
Aug29° / 25°16526.512.33.6
Sep29° / 26°12322.412.13.8
Oct29° / 25°13223.111.83.9
Nov28° / 25°14423.711.54.0
Dec28° / 24°891711.45.4

Cloud cover in September

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 22% 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 58%. Skies tend to cloud over as the month goes on.

0%25%50%75%100%151015202530
Clearer (%)Cloudier (%)
15446
25446
35347
45347
55248
65149
74951
84852
94753
104654
114456
124258
134159
144060
153961
163961
173862
183862
193763
203862
213862
223763
233763
243763
253763
263664
273664
283664
293565
303565

Chance of precipitation in September

Any precipitation

San Fernando gets around 123 mm of rain over 22.4 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 75% and peaks near 78% on the wettest days.

0%20%40%60%80%151015202530
Rain chance (%)
175
275
374
474
575
675
775
876
977
1077
1177
1278
1378
1478
1578
1678
1777
1877
1976
2076
2175
2274
2374
2473
2573
2673
2773
2873
2973
3073

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 66% of days. Sticky, muggy-or-worse air turns up on roughly 100% of them.

0%25%50%75%100%151015202530
Oppressive (%)Miserable (%)
13961
23862
33862
43862
53862
63763
73763
83664
93664
103565
113565
123466
133466
143367
153367
163268
173268
183169
193169
203169
213169
223169
233169
243169
253169
263268
273268
283268
293268
303268

Wind in September

Winds average 14 km/h in September.

Across September, daily wind ranges from about 13 km/h on the calmest days to 14 km/h at its breeziest. It stays fairly steady from day to day.

05101520151015202530
Wind speed (km/h)Feels
113light breeze
213light breeze
313light breeze
413light breeze
513light breeze
614light breeze
714light breeze
814light breeze
914light breeze
1014light breeze
1114light breeze
1214light breeze
1314light breeze
1414light breeze
1514light breeze
1614light breeze
1714light breeze
1814light breeze
1914light breeze
2014light breeze
2114light breeze
2214light breeze
2314light breeze
2414light breeze
2514light breeze
2614light breeze
2714light breeze
2814light breeze
2914light breeze
3014light breeze

Sunrise & sunset in September

DaylightNight

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

Days shrink by about 18 minutes over September. Sunrise moves from 6:00 AM to 5:58 AM, and sunset from 6:12 PM to 5:53 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202530
Daylight (h)Sunrise (AM)Sunset (PM)
112.26:006:12
212.26:006:11
312.25:596:10
412.25:596:10
512.25:596:09
612.25:596:08
712.15:596:08
812.15:596:07
912.15:596:06
1012.15:596:06
1112.15:596:05
1212.15:596:05
1312.15:596:04
1412.15:596:03
1512.15:596:03
1612.15:596:02
1712.05:586:01
1812.05:586:01
1912.05:586:00
2012.05:585:59
2112.05:585:59
2212.05:585:58
2312.05:585:57
2412.05:585:57
2512.05:585:56
2612.05:585:55
2711.95:585:55
2811.95:585:54
2911.95:585:53
3011.95:585:53

Solar energy in September

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in September, about 5.71 kWh/m².

For context, solar energy here swings from a low near 4.74 kWh/m² to a high of 6.25 kWh/m² in April across the year — September's 5.71 kWh/m² falls in the middle.

0246151015202530
Solar energy (kWh/m²)Level
15.8Bright
25.8Bright
35.8Bright
45.8Bright
55.8Bright
65.8Bright
75.8Bright
85.8Bright
95.7Bright
105.7Bright
115.7Bright
125.7Bright
135.7Bright
145.7Bright
155.7Bright
165.7Bright
175.7Bright
185.7Bright
195.6Bright
205.6Bright
215.6Bright
225.6Bright
235.6Bright
245.6Bright
255.6Bright
265.6Bright
275.6Bright
285.6Bright
295.5Bright
305.5Bright
Planning a trip in September

Hazard calendar for San Fernando

In seasonPeak

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

San Fernando's rainy season runs June–December, 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 San Fernando?

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

3.8
Sightseeing
10th-best month of the year
4.9
Beach & pool
8th-best month of the year

September is a weaker month for outdoor sightseeing in San Fernando.

What to pack for San Fernando in September

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

In September, San Fernando sees daytime highs around 29°C and nights near 26°C. Pack light clothes and rain gear. Worth having: sun protection. About 22 days see rain.

light clothesrain gearsun protection

Sea temperature near San Fernando in September

The nearest coast averages about 29°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 20 km away) is warmest in September at about 29°C and coldest in February near 27°C.

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

26°28°30°JanFebMarAprMayJunJulAugSepOctNovDecwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan27Warm
Feb27Warm
Mar27Warm
Apr27Warm
May28Warm
Jun28Warm
Jul28Tropical
Aug29Tropical
Sep29Tropical
Oct29Tropical
Nov28Tropical
Dec28Warm

UV index in San Fernando in September

LowModerateHighVery highExtreme

Clear-sky midday UV in September peaks around 13 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in San Fernando peaks around March 21 at about 14 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 12 at about 9 (very high).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highMar 21UV 14Dec 12UV 9
UV index (midday)Level
Jan11Extreme
Feb13Extreme
Mar14Extreme
Apr14Extreme
May13Extreme
Jun11Extreme
Jul11Extreme
Aug11Extreme
Sep13Extreme
Oct12Extreme
Nov10Very high
Dec9Very high

Air quality in San Fernando 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 San Fernando is worst in June — around 31 µg/m³ PM2.5 (moderate), about 2.2× the cleanest month (November, 14 µg/m³).

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

010203040JanFebMarAprMayJunJulAugSepOctNovDecModerateJun 1530 µg/m³Nov 2314 µg/m³
PM2.5 (µg/m³)Level
Jan15Moderate
Feb18Moderate
Mar19Moderate
Apr23Moderate
May26Moderate
Jun31Moderate
Jul24Moderate
Aug18Moderate
Sep15Moderate
Oct17Moderate
Nov14Moderate
Dec15Moderate
Location & terrain

Where is San Fernando?

San Fernando sits at 10.3°N, 61.5°W, 28 m above sea level, in Trinidad and Tobago. The nearest listed city is Mon Repos, 2.0 km away.

Point FortinChaguanasRio ClaroLaventilleTunapunaParadise

Topography around San Fernando

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

Within 3 km, the terrain around San Fernando has only modest variations in elevation — a maximum elevation change of 156 m around an average of 11 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 318 m; within 80 km, large variations in elevation — a maximum elevation change of 1,037 m.

The land around San Fernando is covered by water (49%) and artificial surfaces (39%) within 3 km, grassland (32%), water (32%) and trees (22%) within 16 km, and water (66%) and trees (22%) within 80 km.

3 km
156 m
16 km
318 m
80 km
1,037 m
treesgrasslandartificial surfaceswaterwetlandmangroves
September weather nearby: Mon Repos 2.0 km · Marabella 4.0 km · Point Fortin 26 km · Chaguanas 27 km · Rio Claro 32 km · Laventille 41 km · Tunapuna 42 km · Paradise 43 km

Trinidad and Tobago travel facts

Travel advisory
Level 3
Reconsider Travel
Power plugs
Type A / B
115 / 230 V · 60 Hz
Prices
≈ 51% of US
price level, 2025
GDP per capita
$18,967
2025
Happiness
5.9 / 10
World Happiness, 2025
Safe drinking water
69%
of population, 2024
Homicide rate
40.4
per 100k, 2022
Road deaths
9.3
per 100k/yr, 2019
Income group
High
World Bank
Religion
Protestant 32%Roman Catholic 22%Hindu 18%other 8%

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 San Fernando (10.2797°, -61.4684°, elevation 28 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. 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).