Climate and average weather in San Martín

In San Martín, the weather is humid, hot, wet, and partly cloudy and remarkably steady, with daytime highs holding near hot levels all year. The wettest stretch peaks around May.

Best: early December to early March

Over the course of the year, the temperature in San Martín typically varies from 21°C to 29°C, and is rarely below 19°C or above 32°C. February is the hottest month of the year, while October is the coldest.

Based on the travel score, the best time of year to visit San Martín for warm-weather activities is from early December to early March.

Hottest
Feb
29°
Coldest
Oct
21°
Wettest
May
644 mm
Driest
Jan
111 mm
Rain / yr
4987 mm
333 wet days
Daylight
11.5–12.5 h
shortest–longest
Elevation
112 m
8.0°N
Clearest
Jan
55% cloud

San Martín is municipality in Cesar, Colombia.

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

San Martín weather by month, at a glance

The whole year in one picture — sky, rain, humidity, temperature and travel score. Click any band to jump to its full chart.

Each stripe is one measure across the whole year, stacked so a single day reads top to bottom. The sky band runs overcast grey on top down to clear blue at the base — more blue means sunnier — followed by the rainfall curve, the humidity band, a temperature strip that tints each stretch of the year by how warm its average high is, and the travel-score line at the foot. Scan straight down any date to read that day across every measure at once; the score climbs highest around early December to early March.

Temperature through the year

Average highAverage lowShaded bands: 10–90% of days

Daily average highs and lows in San Martín, from 1991–2020 of climate data. The shaded bands show the range most days fall in — 10th to 90th percentile.

Temperatures in San Martín stay fairly even through the year, without a distinct hot or cool season. The warmest month is February, with an average high of 29°C and low of 21°C; the coolest is October, with an average low of 21°C and high of 28°C.

Days typically run about 7°C warmer than nights year-round.

15°20°25°30°35°JanFebMarAprMayJunJulAugSepOctNovDec
Avg high (°C)Avg low (°C)
Jan2921
Feb2921
Mar2922
Apr2822
May2822
Jun2821
Jul2821
Aug2821
Sep2821
Oct2821
Nov2821
Dec2821

Average hourly temperature in San Martín

A compact picture of the whole year, hour by hour: each column is a day, each row an hour, and the color is the modeled average temperature. Darker overlays mark night, lighter ones the civil-twilight hours around sunrise and sunset.

Read left to right for the day of the year and top to bottom for the hour of the day; the color is the modeled temperature, cool blues through to hot reds on the same scale as the other charts. A vertical slice is a single day's swing — coolest just before dawn, warmest in the mid-afternoon — while a horizontal slice follows one hour across the seasons. The darker overlay marks night and the lighter one the twilight around sunrise and sunset. Colors run warmest on February afternoons, near 29°C, and coldest before dawn in October, near 21°C.

JanFebMarAprMayJunJulAugSepOctNovDec12 AM2 AM4 AM6 AM8 AM10 AM12 PM2 PM4 PM6 PM8 PM10 PM12 AM

San Martín weather by month

Every month at a glance. Click a month for its detailed page.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan29° / 21°11120.211.64.5
Feb29° / 21°14318.711.74.1
Mar29° / 22°27526.611.93.4
Apr28° / 22°47829.612.22.9
May28° / 22°64430.712.43.0
Jun28° / 21°61729.812.53.1
Jul28° / 21°59130.812.43.2
Aug28° / 21°5883112.33.1
Sep28° / 21°50629.8123.2
Oct28° / 21°45230.111.83.3
Nov28° / 21°3782911.63.3
Dec28° / 21°20626.211.53.8

Chance of rain

How likely it is to rain on a typical day, and how that shifts across the wetter and drier seasons.

San Martín gets about 4987 mm of precipitation a year. On a typical day the chance of rain is very wet, but that rises and falls sharply with the seasons.

The wetter season lasts 8.6 months, from around Mar 23 to Dec 9, peaking in June at about 100% chance on a given day. The drier stretch runs the rest of the year, bottoming out around Jan 30.

May is the wettest month by volume, with 644 mm over about 31 wet days; January is the driest, with 111 mm.

0%10%20%30%40%50%60%70%80%90%100%110%JanFebMarAprMayJunJulAugSepOctNovDecdrierwettermostly drysome rainoften wetvery wetJun 9 · 100%Jan 30 · 63%
Rain on a day (%)Rain days
Jan6520
Feb6719
Mar8627
Apr9830
May9931
Jun9930
Jul9931
Aug10031
Sep9930
Oct9730
Nov9729
Dec8426

Monthly rainfall

Over a full year, San Martín collects about 4987 mm of rain across 333 wet days — roughly 416 mm in an average month.

It doesn’t fall evenly. May is the wettest month with 644 mm, while January is the driest at just 111 mm. The three wettest months alone bring about 37% of the year’s total.

050100150200250300350400450500550600650700750JanFebMarAprMayJunJulAugSepOctNovDec111143275478644617591588506452378206
Rainfall (mm)Rain days
Jan11120
Feb14319
Mar27527
Apr47830
May64431
Jun61730
Jul59131
Aug58831
Sep50630
Oct45230
Nov37829
Dec20626

Clouds and sunshine

ClearMostly clearPartly cloudyMostly cloudyOvercast

How often the daytime sky is clear, partly cloudy or overcast.

In San Martín, the average share of the sky covered by clouds shows significant seasonal variation over the course of the year.

The clearer part of the year begins around December 1 and lasts for 3.8 months, ending around March 27. The clearest month is January, when the sky is clear, mostly clear, or partly cloudy 56% of the time on average.

The cloudier part of the year begins around March 28 and lasts for 8.1 months, ending around November 30. The cloudiest month is September, when it is overcast or mostly cloudy 98% of the time.

0%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%JanFebMarAprMayJunJulAugSepOctNovDecJan 23 · 57%Oct 4 · 1%clearmostly clearpartly cloudymostly cloudyovercastclearercloudierclearer
Clearer (%)Cloudier (%)
Jan5644
Feb4753
Mar2575
Apr595
May298
Jun298
Jul397
Aug397
Sep298
Oct397
Nov991
Dec3466

Daylight, sunrise and sunset

DaylightNight

Hours of daylight through the year, with sunrise and sunset times.

The gold band is daylight — sunrise runs along its lower edge, sunset along the upper — so it widens toward summer and pinches toward winter, with night the dark area above and below. The longest day, around June 9, brings about 12 h 30 min of light; the shortest, around January 1, only 11 h 30 min — a swing of roughly 1 hour.

12 AM4 AM8 AM12 PM4 PM8 PM12 AMJanFebMarAprMayJunJulAugSepOctNovDec
Daylight (h)Sunrise (AM)Sunset (PM)
Jan11.66:165:51
Feb11.76:166:01
Mar11.96:056:02
Apr12.25:496:00
May12.45:396:01
Jun12.55:406:08
Jul12.45:476:12
Aug12.35:506:06
Sep12.05:475:50
Oct11.85:445:34
Nov11.65:505:28
Dec11.56:045:36

Sunny days

How many genuinely sunny days each month brings — days the sky stays clear or mostly clear — banded into plain-language zones.

San Martín averages about 2 sunny days a month — counting the days the sky stays clear or mostly clear — with a clear seasonal swing between 0 and 10 days.

The sunnier stretch runs 3.6 months, from around Dec 6 to Mar 25. The sunniest month is January, with roughly 9 sunny days (mixed).

The greyest month is May, down near 0 sunny days — about 99% fewer than the January peak.

051015JanFebMarAprMayJunJulAugSepOctNovDecsunniergreyersunniergloomymixedJan 2610 daysMay 130 days
Sunny daysSky
Jan10Mixed
Feb7Mixed
Mar4Gloomy
Apr1Gloomy
May0Gloomy
Jun0Gloomy
Jul0Gloomy
Aug0Gloomy
Sep0Gloomy
Oct0Gloomy
Nov0Gloomy
Dec5Gloomy

Humidity comfort

DryComfortableHumidMuggyOppressiveMiserable

Share of days at each humidity comfort level, based on the dew point — the measure that tracks how muggy it actually feels.

Humidity comfort is graded by the dew point — the temperature at which the air would be fully saturated — because it tracks how muggy it actually feels far better than relative humidity does. A low dew point feels dry and crisp; a high one feels sticky and oppressive no matter the reading on a humidity gauge.

San Martín is humid all year round — on a typical day the air feels at least humid, and there is no real dry season to wait for.

The stickiest month is January, when it feels muggy, oppressive or miserable about 98% of the time. Even in January, the mildest month, the air is dry or comfortable only 0% of the time.

0%10%20%30%40%50%60%70%80%90%100%JanFebMarAprMayJunJulAugSepOctNovDecoppressivemuggy
Humid (%)Muggy (%)Oppressive (%)
Jan25643
Feb44847
Mar22969
Apr0892
May0496
Jun0991
Jul02179
Aug01585
Sep01783
Oct02179
Nov01882
Dec03268

Wind

Average wind speed through the year, banded into plain-language speed zones so a number reads as 'breezy' or 'calm' without knowing the scale.

This is the average sustained wind speed at the standard 10 metres above open ground — the steady flow a weather station reports, not the sharper gusts that come and go, which can run half again as fast. It's the number that says whether a place is generally breezy or calm.

Wind in San Martín is steady company: average speeds sit near 4 km/hcalm — in every month of the year, with no meaningful windy or calm season.

0510JanFebMarAprMayJunJulAugSepOctNovDeccalmFeb 7 · 4 km/hApr 12 · 4 km/h
Wind speed (km/h)Feels
Jan4calm
Feb4calm
Mar4calm
Apr4calm
May4calm
Jun4calm
Jul4calm
Aug4calm
Sep4calm
Oct4calm
Nov4calm
Dec4calm

Best time to visit San Martín

TravelBeach/poolTemperatureCloudsPrecipitation

To characterize how pleasant the weather is in San Martín throughout the year, we compute two travel scores — one for general sightseeing, one for beach and pool weather.

Around late February, San Martín is still near the tail of its best-weather window — great conditions with the peak-season crowds already thinning.

Inferred from the travel-score curve; month-by-month visitor numbers are a planned addition.

The travel score favors clear, rainless days with daytime highs between 18°C and 28°C. Based on this score, the best time of year to visit San Martín for general outdoor tourist activities is from mid December to early March, with a peak score in the third week of January.

0246810JanFebMarAprMayJunJulAugSepOctNovDecbest timetravel scoretemperaturecloudsprecipitationJan 16 · 4.5

The travel score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).

Travel score (0–10)Rating
Jan4.5fair
Feb4.1fair
Mar3.4poor
Apr2.9poor
May3.0poor
Jun3.1poor
Jul3.2poor
Aug3.1poor
Sep3.2poor
Oct3.3poor
Nov3.3poor
Dec3.8fair

The beach/pool score favors clear, rainless days with daytime highs between 24°C and 34°C. Based on this score, the best time of year to visit San Martín for hot-weather activities is from late December to mid March, with a peak score in the last week of January.

024681012JanFebMarAprMayJunJulAugSepOctNovDecbest timebeach/pool scoretemperaturecloudsprecipitationJan 30 · 5.6

The beach/pool score (filled area), and its constituents: the temperature score (red line), the cloud cover score (blue line), and the precipitation score (green line).

What to pack for San Martín, by month

EssentialRecommendedOptional

Month by month, what's worth putting in the bag — from the temperature range, rain chance, sun and wind. Tap a month for a quick packing note.

San Martín packs about the same all year — highs hold near 29°C. Across the year the things worth having are light clothes, rain gear and sun protection.

Light clothing
Warm layer
Winter coat
Rain gear
Sun protection
Windbreaker

In February, San Martín sees daytime highs around 29°C and nights near 21°C. Pack light clothes and rain gear. Worth having: sun protection. About 19 days see rain.

UV index (midday) in San Martín by month

LowModerateHighVery highExtreme

Clear-sky midday UV index through the year, shaded by the WHO exposure levels — how much sun protection each month calls for.

Under clear skies, the midday UV index in San Martín peaks around February 16 at about 13 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 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 highFeb 16UV 13Dec 13UV 10
UV index (midday)Level
Jan11Extreme
Feb13Extreme
Mar12Extreme
Apr11Extreme
May12Extreme
Jun13Extreme
Jul12Extreme
Aug12Extreme
Sep13Extreme
Oct12Extreme
Nov10Extreme
Dec10Very high

Average hourly UV index in San Martín

LowModerateHighVery highExtreme

Modeled clear-sky UV for every hour of every day — when in the day sun protection actually matters.

The whole year hour by hour: each column is a day, each row an hour, and the color is the modeled clear-sky UV index — the midday peak scaled down as the sun sits lower in the sky. Darker overlays mark night, lighter ones the civil-twilight hours around sunrise and sunset.

UV falls off far faster than brightness as the sun drops, so even in February the burn window is concentrated in the middle of the day: about 7.5 hours a day reach index 3 (protection recommended), and 6 hours reach 6 or more. Mornings and late afternoons stay comparatively gentle year round.

JanFebMarAprMayJunJulAugSepOctNovDec12 AM2 AM4 AM6 AM8 AM10 AM12 PM2 PM4 PM6 PM8 PM10 PM12 AM
UV ≥ 3 (h/day)UV ≥ 6 (h/day)
Jan7.55.5
Feb7.56
Mar86
Apr7.55.5
May86
Jun86
Jul86
Aug86
Sep86
Oct7.55.5
Nov75
Dec74.5

Air quality in San Martín by month

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see which months the air is worst, not just the yearly average.

Air quality in San Martín is worst in March — around 46 µg/m³ PM2.5 (poor), about 3.7× the cleanest month (December, 13 µg/m³).

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

0204060JanFebMarAprMayJunJulAugSepOctNovDecModeratePoorModerateMar 1844 µg/m³Dec 1113 µg/m³
PM2.5 (µg/m³)Level
Jan16Moderate
Feb26Moderate
Mar46Poor
Apr32Moderate
May23Moderate
Jun21Moderate
Jul21Moderate
Aug19Moderate
Sep16Moderate
Oct14Moderate
Nov13Moderate
Dec13Moderate
Almanac & agriculture

Growing season

Chance of a frost-free dayFrost-free year round

San Martín is frost-free year round — even the coldest nights rarely reach freezing, so there is no start or end to the growing season.

0%25%50%75%100%JanFebMarAprMayJunJulAugSepOctNovDecfrost-free year round
Frost-free chance (%)Frost nights
Jan1000
Feb1000
Mar1000
Apr1000
May1000
Jun1000
Jul1000
Aug1000
Sep1000
Oct1000
Nov1000
Dec1000

Growing degree days

Degree days (base 10°C)Frost-free shaded

Growing degree days tally heat above 10°C: each day adds however many degrees its average temperature runs over that threshold, and cold days add nothing. San Martín banks about 5,347 degree days a year, and the running total — which growers use to time plantings and predict maturity — climbs fastest around March.

02,0004,000JanFebMarAprMayJunJulAugSepOctNovDec
Growing degree days (°C·days)
Jan452
Feb425
Mar471
Apr448
May462
Jun437
Jul446
Aug447
Sep431
Oct446
Nov434
Dec449

Solar energy

Average daily shortwave solar energy reaching the ground, banded into brightness zones so the number means something at a glance.

Solar energy is how much sunlight actually reaches the ground each day, measured in kilowatt-hours per square metre (kWh/m²) — the combined effect of how long the sun is up, how high it climbs, and how much cloud gets in the way. It's the raw fuel a solar panel has to work with: for scale, 1 kWh/m² a day is dim and wintry, while 7+ is desert-bright.

San Martín receives about 5.1 kWh/m² a day of solar energy — bright — and it stays remarkably steady, holding between 4.3 and 5.7 kWh/m² all year. For solar panels, output here is a flat line, not a seasonal wave.

01234567JanFebMarAprMayJunJulAugSepOctNovDecdimmoderatebrightintenseFeb 215.7 kWhNov 144.3 kWh
Solar energy (kWh/m²)Level
Jan5.4Bright
Feb5.7Bright
Mar5.5Bright
Apr4.9Bright
May4.6Bright
Jun5.1Bright
Jul5.5Bright
Aug5.5Bright
Sep5.1Bright
Oct4.6Bright
Nov4.3Bright
Dec4.8Bright

Where is San Martín?

San Martín sits at 8.0°N, 73.5°W, 112 m above sea level, in Colombia. The nearest listed city is Ocaña, 31 km away.

Topography around San Martín

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

Within 3 km, the terrain around San Martín has only modest variations in elevation — a maximum elevation change of 53 m around an average of 105 m above sea level; within 16 km, very significant variations in elevation — a maximum elevation change of 1,315 m; within 80 km, extreme variations in elevation — a maximum elevation change of 3,956 m.

The land around San Martín is covered by grassland (63%) and trees (32%) within 3 km, grassland (58%) and trees (41%) within 16 km, and trees (58%) and grassland (40%) within 80 km.

3 km
53 m
16 km
1,315 m
80 km
3,956 m
treesgrasslandcroplandartificial surfacesbare terrainwater
Nearby: Ocaña 31 km · Aguachica 36 km · Simití 48 km · Morales 50 km · Sabana de Torres 68 km · Puerto Wilches 84 km · El Zulia 101 km · Tiquisio 103 km

Colombia travel facts

Travel advisory
Level 3
Reconsider Travel
Power plugs
Type A / B
120 / 240 V · 60 Hz
Prices
≈ 38% of US
price level, 2025
GDP per capita
$8,562
2025
Happiness
6.0 / 10
World Happiness, 2025
Safe drinking water
74%
of population, 2024
Homicide rate
24.9
per 100k, 2023
Road deaths
15.4
per 100k/yr, 2019
Income group
Upper middle
World Bank
English
Low
EF EPI 480
Religion
Roman Catholic 64%Protestant 17%none 14%atheist 1%

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 Martín (8.0018°, -73.5114°, elevation 112 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).