Climate and average weather in Petatlán

In Petatlán, the weather is humid, hot, wet, and mostly clear and remarkably steady, with daytime highs holding near hot levels all year. The wettest stretch peaks around September.

Best: early January to mid May

Over the course of the year, the temperature in Petatlán typically varies from 20°C to 31°C, and is rarely below 18°C or above 33°C. May is the hottest month of the year, while January is the coldest.

Based on the travel score, the best times of year to visit Petatlán for warm-weather activities are from early January to mid May and mid November to late December.

Hottest
May
31°
Coldest
Jan
20°
Wettest
Sep
338 mm
Driest
Apr
0 mm
Rain / yr
1312 mm
115 wet days
Daylight
10.9–13.0 h
shortest–longest
Elevation
39 m
17.5°N
Clearest
Mar
21% cloud

Petatlán is municipal seat of Petatlán, State of Guerrero, Mexico.

Density
10/km²
people per km²
Founded
1550

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

Petatlán 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 January to mid May.

Temperature through the year

Average highAverage lowShaded bands: 10–90% of days

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

Temperatures in Petatlán stay fairly even through the year, without a distinct hot or cool season. The warmest month is May, with an average high of 31°C and low of 23°C; the coolest is January, with an average low of 20°C and high of 29°C.

Days typically run about 7°C warmer than nights, with the widest day–night swing (around 9°C) in March.

15°20°25°30°35°JanFebMarAprMayJunJulAugSepOctNovDec
Avg high (°C)Avg low (°C)
Jan2920
Feb2920
Mar2920
Apr3021
May3123
Jun3024
Jul3024
Aug3024
Sep2924
Oct2923
Nov2922
Dec2921

How hot and cold Petatlán really feels

Feels-like highFeels-like lowactual air temp

The felt-temperature range through the year — heat index on the day's high (summer humidity), wind chill on the night's low (winter wind). The dashed lines are the plain thermometer; the gap is how much hotter or colder it really feels.

On the hottest afternoons, once humidity is folded in, Petatlán feels like about 35°C (around July 30). About 204 days a year carry some heat stress, peaking in July.

20°25°30°35°JanFebMarAprMayJunJulAugSepOctNovDec
Feels-like high (°C)Air high (°C)Feels-like low (°C)Air low (°C)
Jan30292020
Feb30292020
Mar31292020
Apr31302121
May33312323
Jun34302424
Jul34302424
Aug34302424
Sep33292424
Oct33292323
Nov32292222
Dec31292121

Average hourly temperature in Petatlán

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 May afternoons, near 31°C, and coldest before dawn in January, near 20°C.

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

Petatlán 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° / 20°9111.17.3
Feb29° / 20°50.411.47.3
Mar29° / 20°60.411.97.1
Apr30° / 21°0012.46.5
May31° / 23°243.712.85.6
Jun30° / 24°22018.1134.0
Jul30° / 24°19819.112.93.8
Aug30° / 24°2562112.63.7
Sep29° / 24°33823.512.13.5
Oct29° / 23°21220.311.64.1
Nov29° / 22°355.911.26.2
Dec29° / 21°81.7117.1

Chance of rain

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

Petatlán gets about 1312 mm of precipitation a year. On a typical day the chance of rain is often wet, but that rises and falls sharply with the seasons.

The wetter season lasts 5.3 months, from around May 29 to Nov 6, peaking in September at about 78% chance on a given day. The drier stretch runs the rest of the year, bottoming out around Mar 31.

September is the wettest month by volume, with 338 mm over about 24 wet days; April is the driest, with 0 mm.

0%10%20%30%40%50%60%70%80%90%JanFebMarAprMayJunJulAugSepOctNovDecdrierwetterdriermostly drysome rainoften wetvery wetSep 19 · 78%Mar 31 · 0%
Rain on a day (%)Rain days
Jan41
Feb20
Mar10
Apr00
May134
Jun5818
Jul6319
Aug6721
Sep7824
Oct6520
Nov216
Dec52

Monthly rainfall

Over a full year, Petatlán collects about 1312 mm of rain across 115 wet days — roughly 109 mm in an average month.

It doesn’t fall evenly. September is the wettest month with 338 mm, while April is the driest at just 0 mm. The three wettest months alone bring about 62% of the year’s total.

050100150200250300350400JanFebMarAprMayJunJulAugSepOctNovDec956024220198256338212358
Rainfall (mm)Rain days
Jan91
Feb50
Mar60
Apr00
May244
Jun22018
Jul19819
Aug25621
Sep33824
Oct21220
Nov356
Dec82

Clouds and sunshine

ClearMostly clearPartly cloudyMostly cloudyOvercast

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

In Petatlán, 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 October 29 and lasts for 7.0 months, ending around May 30. The clearest month is March, when the sky is clear, mostly clear, or partly cloudy 87% of the time on average.

The cloudier part of the year begins around May 31 and lasts for 5.0 months, ending around October 28. The cloudiest month is September, when it is overcast or mostly cloudy 86% 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%JanFebMarAprMayJunJulAugSepOctNovDecFeb 27 · 89%Sep 8 · 13%clearmostly clearpartly cloudymostly cloudyovercastclearercloudierclearer
Clearer (%)Cloudier (%)
Jan7921
Feb8614
Mar8713
Apr8218
May7129
Jun3169
Jul2179
Aug1882
Sep1486
Oct4060
Nov7327
Dec7822

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 May 30, brings about 13 hours of light; the shortest, around December 22, only 10 h 54 min — a swing of roughly 2 h 06 min.

12 AM4 AM8 AM12 PM4 PM8 PM12 AMJanFebMarAprMayJunJulAugSepOctNovDec
Daylight (h)Sunrise (AM)Sunset (PM)
Jan11.17:236:26
Feb11.47:176:42
Mar11.96:586:51
Apr12.46:336:57
May12.86:177:06
Jun13.06:147:17
Jul12.96:227:19
Aug12.66:317:07
Sep12.16:366:42
Oct11.66:426:18
Nov11.26:556:05
Dec11.07:136:10

Sunny days

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

Petatlán averages about 14 sunny days a month — counting the days the sky stays clear or mostly clear — with a clear seasonal swing between 1 and 25 days.

The sunnier stretch runs 6.7 months, from around Nov 4 to May 27. The sunniest month is February, with roughly 24 sunny days (brilliant).

The greyest month is September, down near 1 sunny days — about 95% fewer than the February peak.

051015202530JanFebMarAprMayJunJulAugSepOctNovDecsunniergreyersunniergloomymixedbrightbrilliantFeb 2325 daysSep 121 days
Sunny daysSky
Jan21Bright
Feb22Brilliant
Mar25Brilliant
Apr22Bright
May18Bright
Jun5Gloomy
Jul3Gloomy
Aug2Gloomy
Sep1Gloomy
Oct7Gloomy
Nov17Bright
Dec21Bright

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.

Petatlán 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 May, when it feels muggy, oppressive or miserable about 93% of the time. Even in March, the mildest month, the air is dry or comfortable only 3% of the time.

0%10%20%30%40%50%60%70%80%90%100%JanFebMarAprMayJunJulAugSepOctNovDecmiserablemuggyoppressivehumid
Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
Jan2236860
Feb3405520
Mar3385630
Apr1296270
May0747451
Jun0067914
Jul0007822
Aug0007327
Sep0008020
Oct0017820
Nov0119755
Dec1960300

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 Petatlán is steady company: average speeds sit near 6 km/hcalm — in every month of the year, with no meaningful windy or calm season.

0510JanFebMarAprMayJunJulAugSepOctNovDeccalmMay 1 · 7 km/hNov 6 · 5 km/h
Wind speed (km/h)Feels
Jan6calm
Feb6calm
Mar6calm
Apr6calm
May6calm
Jun6calm
Jul5calm
Aug5calm
Sep6calm
Oct5calm
Nov5calm
Dec5calm

Hazard calendar for Petatlán

In seasonPeak

When the seasonal hazards worth planning around — the rainy season, tropical-cyclone risk and dust haze — are active through the year.

Petatlán sits in the eastern Pacific hurricane zone; the season peaks August–September.

Petatlán's monsoon runs June–October, when most of the year's rain falls.

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

Best time to visit Petatlán

TravelBeach/poolTemperatureCloudsPrecipitation

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

Around late April, Petatlán 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 Petatlán for general outdoor tourist activities is from mid November to mid May, with a peak score in the second week of January.

0246810JanFebMarAprMayJunJulAugSepOctNovDecbest timebest timetravel scoretemperaturecloudsprecipitationJan 10 · 7.3

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
Jan7.3good
Feb7.3good
Mar7.1good
Apr6.5good
May5.6good
Jun4.0fair
Jul3.8fair
Aug3.7fair
Sep3.5fair
Oct4.2fair
Nov6.2good
Dec7.1good

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 Petatlán for hot-weather activities is from mid November to late May, with a peak score in the last week of February.

024681012JanFebMarAprMayJunJulAugSepOctNovDecbest timebest timebeach/pool scoretemperaturecloudsprecipitationFeb 23 · 9.3

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 Petatlán, 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.

Petatlán packs about the same all year — highs hold near 31°C. Across the year the things worth having are light clothes and sun protection.

Light clothing
Warm layer
Winter coat
Rain gear
Sun protection
Windbreaker

In May, Petatlán sees daytime highs around 31°C and nights near 23°C. Pack light clothes and sun protection. About 4 days see rain.

Sea temperature near Petatlán

Average ocean temperature at the nearest coast, month by month, banded into swim-comfort zones — the other half of the beach question.

The sea at the nearest coast (about 21 km away) is warmest in August at about 30°C and coldest in March near 27°C.

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

26°28°30°32°JanFebMarAprMayJunJulAugSepOctNovDecwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan28Tropical
Feb28Warm
Mar27Warm
Apr27Warm
May28Tropical
Jun30Tropical
Jul30Tropical
Aug30Tropical
Sep30Tropical
Oct30Tropical
Nov29Tropical
Dec29Tropical

UV index (midday) in Petatlán 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 Petatlán peaks around March 23 at about 13 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 13 at about 7 (very high).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecVery highExtremeVery highMar 23UV 13Dec 13UV 7
UV index (midday)Level
Jan9Very high
Feb11Extreme
Mar13Extreme
Apr13Extreme
May12Extreme
Jun12Extreme
Jul11Extreme
Aug11Extreme
Sep11Extreme
Oct8Very high
Nov8Very high
Dec7High

Average hourly UV index in Petatlán

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 March the burn window is concentrated in the middle of the day: about 8 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)
Jan6.54
Feb7.55.5
Mar86
Apr8.56.5
May86
Jun8.56.5
Jul86
Aug85.5
Sep7.55.5
Oct74
Nov6.53.5
Dec63

Air quality in Petatlán 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 Petatlán is worst in May — around 28 µg/m³ PM2.5 (moderate), about 8.1× the cleanest month (February, 3 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodMay 1625 µg/m³Feb 154 µg/m³
PM2.5 (µg/m³)Level
Jan5Good
Feb3Good
Mar5Good
Apr12Good
May28Moderate
Jun11Good
Jul13Moderate
Aug9Good
Sep7Good
Oct6Good
Nov5Good
Dec5Good
Almanac & agriculture

Growing season

Chance of a frost-free dayFrost-free year round

Petatlán 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. Petatlán banks about 5,783 degree days a year, and the running total — which growers use to time plantings and predict maturity — climbs fastest around July.

02,0004,0006,000JanFebMarAprMayJunJulAugSepOctNovDec
Growing degree days (°C·days)
Jan445
Feb407
Mar459
Apr467
May518
Jun510
Jul530
Aug526
Sep495
Oct504
Nov466
Dec455

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.

Petatlán receives about 5.7 kWh/m² a day of solar energy on average — bright — with a clear seasonal swing between 4.7 and 7.4 kWh/m².

The brighter stretch of the year lasts 4.0 months, from around Feb 9 to Jun 10. The brightest month is April, averaging about 7.4 kWh/m² (intense).

The dimmest month is September, down near 4.9 kWh/m² — roughly 34% less than the April peak.

0123456789JanFebMarAprMayJunJulAugSepOctNovDecdimmerbrighterdimmerdimmoderatebrightintenseApr 227.4 kWhSep 274.7 kWh
Solar energy (kWh/m²)Level
Jan5.1Bright
Feb6.0Bright
Mar6.9Intense
Apr7.4Intense
May7.0Intense
Jun5.6Bright
Jul5.7Bright
Aug5.4Bright
Sep4.8Bright
Oct4.9Bright
Nov5.1Bright
Dec5.0Bright

Where is Petatlán?

Petatlán sits at 17.5°N, 101.3°W, 39 m above sea level, in Mexico. The nearest listed city is Zihuatanejo, 32 km away.

Topography around Petatlán

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

Within 3 km, the terrain around Petatlán has only modest variations in elevation — a maximum elevation change of 155 m around an average of 39 m above sea level; within 16 km, very significant variations in elevation — a maximum elevation change of 1,493 m; within 80 km, extreme variations in elevation — a maximum elevation change of 2,839 m.

The land around Petatlán is covered by trees (43%) and grassland (26%) within 3 km, trees (54%) within 16 km, and trees (56%) and water (33%) within 80 km.

3 km
155 m
16 km
1,493 m
80 km
2,839 m
treesshrubsgrasslandcroplandartificial surfacesbare terrainwaterwetlandmangroves
Nearby: Zihuatanejo 32 km · Técpan de Galeana 76 km · Atoyac de Álvarez 96 km · Ciudad Lázaro Cárdenas 109 km · Ciudad Altamirano 111 km · Las Guacamayas 113 km · La Orilla 114 km · Huetamo de Núñez 127 km

Mexico travel facts

Travel advisory
Level 2
Exercise Increased Caution
Power plugs
Type A / B
120 / 127 V · 60 Hz
Prices
≈ 54% of US
price level, 2025
GDP per capita
$13,889
2025
Happiness
7.0 / 10
World Happiness, 2025
Safe drinking water
43%
of population, 2024
Homicide rate
24.9
per 100k, 2023
Road deaths
12.8
per 100k/yr, 2019
Income group
Upper middle
World Bank
English
Very low
EF EPI 440
Religion
Catholic 78%no religion 11%other Evangelical Churches 8%Jehovah Witness 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 Petatlán (17.5377°, -101.268°, elevation 39 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. Tropical-cyclone seasons are the published climatological basin seasons (NOAA National Hurricane Center / regional warning centres). 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).