Climate and average weather in Heroica Guaymas

In Heroica Guaymas, the summers are muggy, sweltering, dry, and mostly clear and the winters are warm and mostly clear.

Best: early November to late April

Over the course of the year, the temperature in Heroica Guaymas typically varies from 12°C to 35°C, and is rarely below 9°C or above 37°C. July is the hottest month of the year, while January is the coldest.

Based on the travel score, the best time of year to visit Heroica Guaymas for warm-weather activities is from early November to late April.

Hottest
Jul
35°
Coldest
Jan
12°
Wettest
Sep
59 mm
Driest
May
0 mm
Rain / yr
164 mm
21 wet days
Daylight
10.2–13.8 h
shortest–longest
Elevation
18 m
27.9°N
Clearest
Jun
12% cloud

Heroica Guaymas is municipal seat of Guaymas, State of Sonora, Mexico.

Founded
1701

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

Heroica Guaymas 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 November to late April.

Temperature through the year

Average highAverage lowShaded bands: 10–90% of days

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

The hot season lasts 4.7 months, from May 27 to October 15, with daily high temperatures above 32°C. The hottest month of the year in Heroica Guaymas is July, with an average high of 35°C and low of 29°C.

The cool season lasts 3.2 months, from November 30 to March 5, with daily high temperatures below 25°C. The coldest month of the year in Heroica Guaymas is January, with an average low of 12°C and high of 23°C.

Days typically run about 9°C warmer than nights, with the widest day–night swing (around 11°C) in April.

10°20°30°40°JanFebMarAprMayJunJulAugSepOctNovDec
Avg high (°C)Avg low (°C)
Jan2312
Feb2413
Mar2615
Apr2818
May3121
Jun3425
Jul3529
Aug3529
Sep3427
Oct3223
Nov2717
Dec2313

How hot and cold Heroica Guaymas 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, Heroica Guaymas feels like about 44°C (around August 13). About 146 days a year carry some heat stress, and 93 of them tip into dangerous heat (feels-like above 39°C), peaking in August.

10°20°30°40°JanFebMarAprMayJunJulAugSepOctNovDecdangerous heat
Feels-like high (°C)Air high (°C)Feels-like low (°C)Air low (°C)
Jan23231212
Feb24241313
Mar26261515
Apr28281818
May31312121
Jun36342525
Jul41352829
Aug43352929
Sep41342727
Oct33322323
Nov27271717
Dec23231313

Average hourly temperature in Heroica Guaymas

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 July afternoons, near 35°C, and coldest before dawn in January, near 12°C.

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

Heroica Guaymas 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
Jan23° / 12°81.310.48.7
Feb24° / 13°111.5118.7
Mar26° / 15°50.511.88.8
Apr28° / 18°10.212.68.0
May31° / 21°00.113.46.1
Jun34° / 25°10.213.74.4
Jul35° / 29°102.413.63.2
Aug35° / 29°264.5133.0
Sep34° / 27°595.512.23.7
Oct32° / 23°172.211.35.5
Nov27° / 17°121.310.68.2
Dec23° / 13°131.510.38.7

Chance of rain

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

Heroica Guaymas gets about 164 mm of precipitation a year. On a typical day the chance of rain is mostly dry, but that rises and falls sharply with the seasons.

The wetter season lasts 3.4 months, from around Jul 6 to Oct 18, peaking in September at about 22% chance on a given day. The drier stretch runs the rest of the year, bottoming out around Apr 23.

September is the wettest month by volume, with 59 mm over about 6 wet days; May is the driest, with 0 mm.

0%10%20%30%JanFebMarAprMayJunJulAugSepOctNovDecdrierwetterdriermostly drysome rainSep 2 · 22%Apr 23 · 0%
Rain on a day (%)Rain days
Jan41
Feb52
Mar21
Apr10
May00
Jun10
Jul72
Aug155
Sep186
Oct72
Nov51
Dec52

Monthly rainfall

Over a full year, Heroica Guaymas collects about 164 mm of rain across 21 wet days — roughly 14 mm in an average month.

It doesn’t fall evenly. September is the wettest month with 59 mm, while May is the driest at just 0 mm. The three wettest months alone bring about 62% of the year’s total.

0255075JanFebMarAprMayJunJulAugSepOctNovDec8115101102659171213
Rainfall (mm)Rain days
Jan81
Feb112
Mar51
Apr10
May00
Jun10
Jul102
Aug265
Sep596
Oct172
Nov121
Dec132

Clouds and sunshine

ClearMostly clearPartly cloudyMostly cloudyOvercast

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

In Heroica Guaymas, the average share of the sky covered by clouds shows moderate seasonal variation over the course of the year.

The clearer part of the year begins around April 21 and lasts for 2.5 months, ending around July 6. The clearest month is June, when the sky is clear, mostly clear, or partly cloudy 93% of the time on average.

The cloudier part of the year begins around November 7 and lasts for 4.3 months, ending around March 16. The cloudiest month is February, when it is overcast or mostly cloudy 32% 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%JanFebMarAprMayJunJulAugSepOctNovDecJun 14 · 95%Feb 16 · 67%clearmostly clearpartly cloudymostly cloudyovercastcloudierclearercloudier
Clearer (%)Cloudier (%)
Jan7327
Feb6832
Mar7723
Apr8020
May9010
Jun937
Jul7525
Aug7327
Sep8515
Oct8713
Nov7723
Dec7525

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 15, brings about 13 h 48 min of light; the shortest, around December 14, only 10 h 12 min — a swing of roughly 3 h 36 min.

12 AM4 AM8 AM12 PM4 PM8 PM12 AMJanFebMarAprMayJunJulAugSepOctNovDec
Daylight (h)Sunrise (AM)Sunset (PM)
Jan10.47:215:45
Feb11.07:086:09
Mar11.86:396:27
Apr12.66:046:44
May13.45:387:01
Jun13.75:317:17
Jul13.65:417:18
Aug13.05:586:58
Sep12.26:136:23
Oct11.36:295:48
Nov10.66:515:27
Dec10.37:135:27

Sunny days

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

Heroica Guaymas averages about 21 sunny days a month — counting the days the sky stays clear or mostly clear — with a clear seasonal swing between 15 and 28 days.

The sunnier stretch runs 3.6 months, from around Mar 18 to Jul 4. The sunniest month is June, with roughly 27 sunny days (brilliant).

The greyest month is July, down near 18 sunny days — about 34% fewer than the June peak.

051015202530JanFebMarAprMayJunJulAugSepOctNovDecgreyersunniergreyergloomymixedbrightbrilliantJun 1328 daysJul 2615 days
Sunny daysSky
Jan20Bright
Feb17Bright
Mar21Bright
Apr22Bright
May26Brilliant
Jun26Brilliant
Jul18Bright
Aug17Bright
Sep23Brilliant
Oct25Brilliant
Nov21Bright
Dec20Bright

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.

In Heroica Guaymas, how humid it feels changes dramatically over the year.

The more humid part of the year lasts 5.6 months, from around May 22 to November 8. The muggiest month is July, when the air feels humid, muggy or worse about 99% of the time.

The most comfortable stretch runs from around November 9 to May 21, and January is the most comfortable month — the air is dry or comfortable 98% of the time.

0%10%20%30%40%50%60%70%80%90%100%JanFebMarAprMayJunJulAugSepOctNovDecJan 22 · 99%Jul 24 · 0%humidmiserablemuggycomfortableoppressivedrycomfortablehumidcomfortable
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
Jan84142000
Feb78175000
Mar76195000
Apr63279200
May2931231530
Jun3111623389
Jul01264844
Aug00022078
Sep01392067
Oct61223291811
Nov3330251010
Dec74197000

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 Heroica Guaymas is steady company: average speeds sit near 12 km/hlight breeze — in every month of the year, with no meaningful windy or calm season.

05101520JanFebMarAprMayJunJulAugSepOctNovDeccalmlight breezeJul 6 · 14 km/hOct 1 · 11 km/h
Wind speed (km/h)Feels
Jan12light breeze
Feb12light breeze
Mar13light breeze
Apr13light breeze
May12calm
Jun13light breeze
Jul14light breeze
Aug13light breeze
Sep12calm
Oct11calm
Nov12calm
Dec13light breeze

Hazard calendar for Heroica Guaymas

In seasonPeak

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

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

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

Best time to visit Heroica Guaymas

TravelBeach/poolTemperatureCloudsPrecipitation

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

Around mid November, Heroica Guaymas is still near the start of its best-weather window — great conditions with the peak-season crowds not yet at full swing.

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 Heroica Guaymas for general outdoor tourist activities is from early November to late April, with a peak score in the second week of March.

0246810JanFebMarAprMayJunJulAugSepOctNovDecbest timebest timetravel scoretemperaturecloudsprecipitationMar 13 · 8.9

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
Jan8.7ideal
Feb8.7ideal
Mar8.8ideal
Apr7.9ideal
May6.1good
Jun4.4fair
Jul3.2poor
Aug3.0poor
Sep3.7fair
Oct5.5fair
Nov8.1ideal
Dec8.7ideal

The beach/pool score favors clear, rainless days with daytime highs between 24°C and 34°C. Based on this score, the best times of year to visit Heroica Guaymas for hot-weather activities run from late February to late June and again from late September to early December, with a peak score in the last week of April.

024681012JanFebMarAprMayJunJulAugSepOctNovDecbest timebest timebeach/pool scoretemperaturecloudsprecipitationApr 27 · 9.2

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 Heroica Guaymas, 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.

For a warm-season trip around July (highs near 35°C), the essentials are light clothes and sun protection. In the cold season around January (highs near 23°C), pack light clothes.

Light clothing
Warm layer
Winter coat
Rain gear
Sun protection
Windbreaker

In July, Heroica Guaymas sees daytime highs around 35°C and nights near 29°C. Pack light clothes and sun protection.

Sea temperature near Heroica Guaymas

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

The sea offshore is warmest in August at about 30°C and coldest in January near 18°C.

It's comfortable for a long swim from Apr 6 to Dec 15 — about 8.4 months when the water holds above 20°C.

15°20°25°30°JanFebMarAprMayJunJulAugSepOctNovDeccoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°C)Comfort
Jan18Cool
Feb18Cool
Mar19Cool
Apr21Refreshing
May24Refreshing
Jun27Warm
Jul29Tropical
Aug30Tropical
Sep30Tropical
Oct28Warm
Nov23Refreshing
Dec20Cool

UV index (midday) in Heroica Guaymas 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 Heroica Guaymas peaks around July 14 at about 12 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 19 at about 4 (moderate).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecHighVery highExtremeVery highHighModerateJul 14UV 12Dec 19UV 4
UV index (midday)Level
Jan5Moderate
Feb6High
Mar8Very high
Apr10Extreme
May10Extreme
Jun12Extreme
Jul12Extreme
Aug11Extreme
Sep10Very high
Oct7Very high
Nov6High
Dec4Moderate

Average hourly UV index in Heroica Guaymas

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 July the burn window is concentrated in the middle of the day: about 9 hours a day reach index 3 (protection recommended), and 6.5 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)
Jan4.50
Feb5.50
Mar74
Apr7.55.5
May85.5
Jun8.56.5
Jul96.5
Aug86
Sep7.55
Oct63
Nov50
Dec3.50

Air quality in Heroica Guaymas 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 Heroica Guaymas is worst in July — around 18 µg/m³ PM2.5 (moderate), about 3.9× the cleanest month (January, 5 µg/m³).

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

01020JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodJul 1917 µg/m³Jan 115 µg/m³
PM2.5 (µg/m³)Level
Jan5Good
Feb5Good
Mar5Good
Apr6Good
May5Good
Jun8Good
Jul18Moderate
Aug13Moderate
Sep8Good
Oct5Good
Nov5Good
Dec5Good
Almanac & agriculture

Growing season

Chance of a frost-free dayFrost-free year round

Heroica Guaymas 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. Heroica Guaymas banks about 5,355 degree days a year, and the running total — which growers use to time plantings and predict maturity — climbs fastest around August.

02,0004,000JanFebMarAprMayJunJulAugSepOctNovDec
Growing degree days (°C·days)
Jan232
Feb236
Mar321
Apr384
May496
Jun585
Jul671
Aug676
Sep616
Oct531
Nov360
Dec248

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.

Heroica Guaymas receives about 6.1 kWh/m² a day of solar energy on average — intense — with a clear seasonal swing between 3.9 and 8.2 kWh/m².

The brighter stretch of the year lasts 6.0 months, from around Mar 8 to Sep 6. The brightest month is May, averaging about 8.1 kWh/m² (intense).

The dimmest month is December, down near 3.9 kWh/m² — roughly 52% less than the May peak.

0123456789JanFebMarAprMayJunJulAugSepOctNovDecdimmerbrighterdimmerdimmoderatebrightintenseMay 278.2 kWhDec 143.9 kWh
Solar energy (kWh/m²)Level
Jan4.2Bright
Feb5.0Bright
Mar6.4Intense
Apr7.5Intense
May8.1Intense
Jun8.0Intense
Jul7.1Intense
Aug6.5Intense
Sep5.9Bright
Oct5.4Bright
Nov4.4Bright
Dec3.9Moderate

Where is Heroica Guaymas?

Heroica Guaymas sits at 27.9°N, 110.9°W, 18 m above sea level, in Mexico. The nearest listed city is Empalme, 10 km away.

Topography around Heroica Guaymas

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

Within 3 km, the terrain around Heroica Guaymas has significant variations in elevation — a maximum elevation change of 469 m around an average of 58 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 469 m; within 80 km, large variations in elevation — a maximum elevation change of 1,146 m.

The land around Heroica Guaymas is covered by shrubs (40%) and artificial surfaces (33%) within 3 km, water (51%) and shrubs (34%) within 16 km, and shrubs (50%) and water (38%) within 80 km.

3 km
469 m
16 km
469 m
80 km
1,146 m
treesshrubscroplandartificial surfacesbare terrainwatermangroves
Nearby: Empalme 10 km · San Carlos 15 km · Esperanza 102 km · Ciudad Obregón 106 km · Miguel Alemán (La Doce) 117 km · Hermosillo 130 km · Navojoa 172 km · Huatabampo 174 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 Heroica Guaymas (27.9199°, -110.8989°, elevation 18 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).