Climate and average weather in Mercedes

In Mercedes, the summers are muggy, sweltering, fairly dry, and mostly clear and the winters are warm and partly cloudy.

Best: late October to late March

Over the course of the year, the temperature in Mercedes typically varies from 53°F to 97°F, and is rarely below 40°F or above 102°F. August is the hottest month of the year, while January is the coldest.

Based on the travel score, the best time of year to visit Mercedes for warm-weather activities is from late October to late March.

Hottest
Aug
97°
Coldest
Jan
53°
Wettest
Sep
3.6 in
Driest
Feb
1.0 in
Rain / yr
22.3 in
82 wet days
Daylight
10.4–13.6 h
shortest–longest
Elevation
69 ft
26.1°N
Clearest
Jun
43% cloud

Mercedes is city in Texas, USA.

Density
559/km²
people per km²
Founded
1907

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

Mercedes 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 late October to late March.

Temperature through the year

Average highAverage lowShaded bands: 10–90% of days

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

The hot season lasts 4.3 months, from May 14 to September 20, with daily high temperatures above 91°F. The hottest month of the year in Mercedes is August, with an average high of 97°F and low of 78°F.

The cool season lasts 2.6 months, from November 29 to February 15, with daily high temperatures below 76°F. The coldest month of the year in Mercedes is January, with an average low of 53°F and high of 72°F.

Days typically run about 19°F warmer than nights year-round.

40°60°80°100°JanFebMarAprMayJunJulAugSepOctNovDec
Avg high (°F)Avg low (°F)
Jan7253
Feb7656
Mar8162
Apr8768
May9173
Jun9577
Jul9778
Aug9778
Sep9275
Oct8768
Nov7960
Dec7354

How hot and cold Mercedes 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, Mercedes feels like about 109°F (around August 10). About 176 days a year carry some heat stress, and 103 of them tip into dangerous heat (feels-like above 102°F), peaking in August.

60°80°100°JanFebMarAprMayJunJulAugSepOctNovDecdangerous heat
Feels-like high (°F)Air high (°F)Feels-like low (°F)Air low (°F)
Jan72725353
Feb76765656
Mar81816262
Apr88876868
May97917373
Jun105957777
Jul107977878
Aug108977878
Sep100927575
Oct89876868
Nov79796060
Dec73735454

Average hourly temperature in Mercedes

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 August afternoons, near 97°F, and coldest before dawn in January, near 53°F.

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

Mercedes weather by month

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

MonthHigh / Low (°F)Rainfall (inches)Wet daysDaylight (hours)Travel score
Jan72° / 53°1.14.810.57.4
Feb76° / 56°1.04.811.17.7
Mar81° / 62°1.55.511.87.0
Apr87° / 68°1.75.512.65.3
May91° / 73°2.16.913.33.8
Jun95° / 77°2.17.713.62.7
Jul97° / 78°2.2713.52.3
Aug97° / 78°1.77.712.92.1
Sep92° / 75°3.61312.23.2
Oct87° / 68°2.57.211.45.3
Nov79° / 60°1.56.210.77.4
Dec73° / 54°1.35.410.47.5

Chance of rain

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

Mercedes gets about 22.3 in of precipitation a year. On a typical day the chance of rain is some rain, but that rises and falls sharply with the seasons.

The wetter season lasts 2.2 months, from around Aug 14 to Oct 18, peaking in September at about 48% chance on a given day. The drier stretch runs the rest of the year, bottoming out around Jan 10.

September is the wettest month by volume, with 3.6 in over about 13 wet days; February is the driest, with 1.0 in.

0%10%20%30%40%50%60%JanFebMarAprMayJunJulAugSepOctNovDecdrierwetterdriermostly drysome rainoften wetvery wetSep 10 · 48%Jan 10 · 16%
Rain on a day (%)Rain days
Jan165
Feb175
Mar186
Apr186
May227
Jun268
Jul227
Aug268
Sep4113
Oct247
Nov206
Dec175

Monthly rainfall

Over a full year, Mercedes collects about 22.3 in of rain across 82 wet days — roughly 1.9 in in an average month.

It doesn’t fall evenly. September is the wettest month with 3.6 in, while February is the driest at just 1.0 in. The three wettest months alone bring about 37% of the year’s total.

00.511.522.533.544.5JanFebMarAprMayJunJulAugSepOctNovDec1.11.01.51.72.12.12.21.73.62.51.51.3
Rainfall (in)Rain days
Jan1.15
Feb1.05
Mar1.56
Apr1.76
May2.17
Jun2.18
Jul2.27
Aug1.78
Sep3.613
Oct2.57
Nov1.56
Dec1.35

Clouds and sunshine

ClearMostly clearPartly cloudyMostly cloudyOvercast

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

In Mercedes, 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 May 10 and lasts for 3.7 months, ending around August 29. The clearest month is June, when the sky is clear, mostly clear, or partly cloudy 74% of the time on average.

The cloudier part of the year begins around November 7 and lasts for 6.0 months, ending around May 9. The cloudiest month is January, when it is overcast or mostly cloudy 53% 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 10 · 78%Jan 31 · 45%clearmostly clearpartly cloudymostly cloudyovercastcloudierclearercloudier
Clearer (%)Cloudier (%)
Jan4753
Feb5050
Mar5248
Apr5446
May6535
Jun7426
Jul6931
Aug6634
Sep6040
Oct6931
Nov5941
Dec5050

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 5, brings about 13 h 36 min of light; the shortest, around January 1, only 10 h 24 min — a swing of roughly 3 h 12 min.

12 AM4 AM8 AM12 PM4 PM8 PM12 AMJanFebMarAprMayJunJulAugSepOctNovDec
Daylight (h)Sunrise (AM)Sunset (PM)
Jan10.57:255:57
Feb11.17:146:19
Mar11.86:476:36
Apr12.66:136:50
May13.35:507:06
Jun13.65:437:21
Jul13.55:537:22
Aug12.96:087:04
Sep12.26:216:31
Oct11.46:365:58
Nov10.76:565:38
Dec10.47:175:39

Sunny days

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

Mercedes averages about 13 sunny days a month — counting the days the sky stays clear or mostly clear — with a clear seasonal swing between 10 and 17 days.

The sunnier stretch runs 3.2 months, from around May 20 to Aug 25. The sunniest month is June, with roughly 16 sunny days (bright).

The greyest month is January, down near 11 sunny days — about 32% fewer than the June peak.

05101520JanFebMarAprMayJunJulAugSepOctNovDecgreyersunniergreyergloomymixedbrightJun 1217 daysJan 3010 days
Sunny daysSky
Jan11Mixed
Feb11Mixed
Mar12Mixed
Apr12Mixed
May13Mixed
Jun16Bright
Jul16Bright
Aug14Mixed
Sep12Mixed
Oct15Bright
Nov13Mixed
Dec12Mixed

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 Mercedes, how humid it feels changes dramatically over the year.

The more humid part of the year lasts 6.6 months, from around April 8 to October 24. The muggiest month is June, when the air feels humid, muggy or worse about 100% of the time.

The most comfortable stretch runs from around October 25 to April 7, and January is the most comfortable month — the air is dry or comfortable 75% of the time.

0%10%20%30%40%50%60%70%80%90%100%JanFebMarAprMayJunJulAugSepOctNovDecJan 10 · 77%Jun 5 · 0%miserablehumidmuggyoppressivecomfortabledrycomfortablehumidcomfortable
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
Jan591616900
Feb4716201700
Mar3013203240
Apr15101635231
May34722586
Jun00187120
Jul00038116
Aug00037818
Sep136125524
Oct1291623336
Nov3216182590
Dec5413161520

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.

Across the year, average wind speed in Mercedes is typically light breeze, near 10 mph, and varies moderately with the seasons.

The windier part of the year lasts 6.0 months, from around Feb 12 to Aug 13. The windiest month is May, averaging about 12 mph (light breeze).

The calmer part of the year runs from around Aug 14 to Feb 11, with September the calmest month at about 8 mph.

051015JanFebMarAprMayJunJulAugSepOctNovDeccalmerwindiercalmercalmlight breezebreezyMay 4 · 12 mphSep 15 · 8 mph
Wind speed (mph)Feels
Jan10light breeze
Feb10light breeze
Mar11light breeze
Apr12light breeze
May12light breeze
Jun11light breeze
Jul11light breeze
Aug10light breeze
Sep8light breeze
Oct9light breeze
Nov9light breeze
Dec10light breeze

Best time to visit Mercedes

TravelBeach/poolTemperatureCloudsPrecipitation

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

Around late March, Mercedes 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 64°F and 82°F. Based on this score, the best time of year to visit Mercedes for general outdoor tourist activities is from late October to late March, with a peak score in the last week of November.

0246810JanFebMarAprMayJunJulAugSepOctNovDecbest timebest timetravel scoretemperaturecloudsprecipitationNov 29 · 7.8

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
Jan7.4good
Feb7.6ideal
Mar7.0good
Apr5.3fair
May3.8fair
Jun2.7poor
Jul2.3poor
Aug2.1poor
Sep3.2poor
Oct5.3fair
Nov7.3good
Dec7.5ideal

The beach/pool score favors clear, rainless days with daytime highs between 75°F and 93°F. Based on this score, the best times of year to visit Mercedes for hot-weather activities run from early February to early June and again from late September to early December, with a peak score in the last week of October.

024681012JanFebMarAprMayJunJulAugSepOctNovDecbest timebest timebeach/pool scoretemperaturecloudsprecipitationOct 26 · 7.8

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 Mercedes, 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 August (highs near 97°F), the essentials are light clothes and sun protection. In the cold season around January (highs near 72°F), pack light clothes.

Light clothing
Warm layer
Winter coat
Rain gear
Sun protection
Windbreaker

In August, Mercedes sees daytime highs around 97°F and nights near 78°F. Pack light clothes and sun protection. About 8 days see rain.

UV index (midday) in Mercedes 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 Mercedes peaks around June 21 at about 12 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 22 at about 5 (moderate).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecHighVery highExtremeVery highExtremeVery highHighJun 21UV 12Dec 22UV 5
UV index (midday)Level
Jan5Moderate
Feb7High
Mar8Very high
Apr11Extreme
May9Very high
Jun12Extreme
Jul11Extreme
Aug11Extreme
Sep10Very high
Oct8Very high
Nov6High
Dec5Moderate

Average hourly UV index in Mercedes

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 June the burn window is concentrated in the middle of the day: about 8.5 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
Feb63
Mar74
Apr86
May85
Jun8.56.5
Jul8.56
Aug86
Sep7.55
Oct6.53.5
Nov5.50
Dec4.50

Air quality in Mercedes 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 Mercedes is worst in July — around 26 µg/m³ PM2.5 (moderate), about 3.5× the cleanest month (November, 7 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodJul 1625 µg/m³Nov 107 µg/m³
PM2.5 (µg/m³)Level
Jan9Good
Feb10Good
Mar11Good
Apr13Moderate
May20Moderate
Jun21Moderate
Jul26Moderate
Aug19Moderate
Sep12Moderate
Oct8Good
Nov7Good
Dec9Good
Almanac & agriculture

Growing season

Chance of a frost-free dayFrost-free year round

Mercedes 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
Jan990
Feb990
Mar1000
Apr1000
May1000
Jun1000
Jul1000
Aug1000
Sep1000
Oct1000
Nov1000
Dec990

Growing degree days

Degree days (base 50°F)Frost-free shaded

Growing degree days tally heat above 50°F: each day adds however many degrees its average temperature runs over that threshold, and cold days add nothing. Mercedes banks about 9,566 degree days a year, and the running total — which growers use to time plantings and predict maturity — climbs fastest around August.

02,5005,0007,50010,000JanFebMarAprMayJunJulAugSepOctNovDec
Growing degree days (°F·days)
Jan377
Feb452
Mar668
Apr816
May1,005
Jun1,083
Jul1,152
Aug1,158
Sep997
Oct849
Nov589
Dec418

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.

Mercedes receives about 5.0 kWh/m² a day of solar energy on average — bright — with a clear seasonal swing between 3.0 and 6.8 kWh/m².

The brighter stretch of the year lasts 6.3 months, from around Mar 23 to Sep 30. The brightest month is July, averaging about 6.7 kWh/m² (intense).

The dimmest month is December, down near 3.0 kWh/m² — roughly 55% less than the July peak.

012345678JanFebMarAprMayJunJulAugSepOctNovDecdimmerbrighterdimmerdimmoderatebrightintenseJul 206.8 kWhDec 243.0 kWh
Solar energy (kWh/m²)Level
Jan3.2Moderate
Feb3.9Moderate
Mar4.8Bright
Apr5.8Bright
May6.3Intense
Jun6.6Intense
Jul6.7Intense
Aug6.4Intense
Sep5.2Bright
Oct4.5Bright
Nov3.4Moderate
Dec3.0Moderate

Where is Mercedes?

Mercedes sits at 26.1°N, 97.9°W, 69 ft above sea level, in United States. The nearest listed city is Weslaco, 5.0 mi away.

Topography around Mercedes

How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of Mercedes.

Within 2 miles, the terrain around Mercedes has only modest variations in elevation — a maximum elevation change of 39 ft around an average of 66 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 174 ft; within 50 miles, only modest variations in elevation — a maximum elevation change of 617 ft.

The land around Mercedes is covered by grassland (31%), cropland (26%) and trees (20%) within 2 miles, cropland (52%) and grassland (20%) within 10 miles, and cropland (40%) and grassland (24%) within 50 miles.

2 miles
39 ft
10 miles
174 ft
50 miles
617 ft
treesshrubsgrasslandcroplandartificial surfacesbare terrainwaterwetland
Nearby: Weslaco 5.0 mi · Donna 8.7 mi · Alamo 13 mi · Harlingen 14 mi · San Juan 16 mi · Ciudad Río Bravo 16 mi · Pharr 17 mi · San Benito 17 mi

United States travel facts

Power plugs
Type A / B
120 V · 60 Hz
Prices
≈ 100% of US
price level, 2025
GDP per capita
$90,027
2025
Happiness
6.8 / 10
World Happiness, 2025
Safe drinking water
98%
of population, 2024
Homicide rate
5.8
per 100k, 2023
Road deaths
12.7
per 100k/yr, 2019
Income group
High
World Bank
Religion
Protestant 47%unaffiliated 23%Roman Catholic 21%Jewish 2%

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 Mercedes (26.1498°, -97.9136°, elevation 69 ft), 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).