Climate and average weather in Bay City

In Bay City, the summers are muggy, sweltering, showery, and partly cloudy and the winters are mild and partly cloudy.

Best: mid January to early May

Over the course of the year, the temperature in Bay City typically varies from 47°F to 92°F, and is rarely below 33°F or above 97°F. August is the hottest month of the year, while January is the coldest.

Based on the travel score, the best times of year to visit Bay City for warm-weather activities are from mid January to early May and early October to early January.

Hottest
Aug
92°
Coldest
Jan
47°
Wettest
Sep
4.5 in
Driest
Feb
2.6 in
Rain / yr
42.1 in
120 wet days
Daylight
10.1–13.9 h
shortest–longest
Elevation
52 ft
29.0°N
Clearest
Oct
42% cloud

Bay City is city in and the county seat of Matagorda County, Texas, United States.

Density
772/km²
people per km²

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

Bay City 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 mid January to early May.

Temperature through the year

Average highAverage lowShaded bands: 10–90% of days

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

The hot season lasts 4.5 months, from May 17 to October 1, with daily high temperatures above 85°F. The hottest month of the year in Bay City is August, with an average high of 92°F and low of 76°F.

The cool season lasts 2.8 months, from November 29 to February 21, with daily high temperatures below 69°F. The coldest month of the year in Bay City is January, with an average low of 47°F and high of 64°F.

Days typically run about 17°F warmer than nights year-round.

40°60°80°100°JanFebMarAprMayJunJulAugSepOctNovDec
Avg high (°F)Avg low (°F)
Jan6447
Feb6850
Mar7356
Apr7962
May8570
Jun9075
Jul9176
Aug9276
Sep8872
Oct8263
Nov7355
Dec6648

How hot and cold Bay City 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, Bay City feels like about 104°F (around August 6). About 129 days a year carry some heat stress, and 31 of them tip into dangerous heat (feels-like above 102°F), peaking in August.

40°60°80°100°JanFebMarAprMayJunJulAugSepOctNovDecdangerous heat
Feels-like high (°F)Air high (°F)Feels-like low (°F)Air low (°F)
Jan64644347
Feb68684950
Mar73735656
Apr79796262
May89857070
Jun98907575
Jul102917676
Aug103927676
Sep94887272
Oct83826363
Nov73735555
Dec66664548

Average hourly temperature in Bay City

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 92°F, and coldest before dawn in January, near 47°F.

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

Bay City 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
Jan64° / 47°3.59.310.46.0
Feb68° / 50°2.68.3116.4
Mar73° / 56°3.27.711.87.1
Apr79° / 62°3.38.512.76.9
May85° / 70°3.49.513.45.3
Jun90° / 75°4.012.213.83.8
Jul91° / 76°3.312.313.73.4
Aug92° / 76°3.612.4133.2
Sep88° / 72°4.513.112.24.2
Oct82° / 63°3.89.211.36.5
Nov73° / 55°3.58.710.67.1
Dec66° / 48°3.48.910.26.2

Chance of rain

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

Bay City gets about 42.1 in 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 4.2 months, from around May 23 to Sep 27, peaking in September at about 50% chance on a given day. The drier stretch runs the rest of the year, bottoming out around Mar 22.

September is the wettest month by volume, with 4.5 in over about 13 wet days; February is the driest, with 2.6 in.

0%10%20%30%40%50%60%JanFebMarAprMayJunJulAugSepOctNovDecdrierwetterdriermostly drysome rainoften wetvery wetSep 5 · 50%Mar 22 · 25%
Rain on a day (%)Rain days
Jan309
Feb298
Mar268
Apr279
May3110
Jun4012
Jul4012
Aug4112
Sep4313
Oct299
Nov299
Dec299

Monthly rainfall

Over a full year, Bay City collects about 42.1 in of rain across 120 wet days — roughly 3.5 in in an average month.

It doesn’t fall evenly. September is the wettest month with 4.5 in, while February is the driest at just 2.6 in. The three wettest months alone bring about 29% of the year’s total.

0123456JanFebMarAprMayJunJulAugSepOctNovDec3.52.63.23.33.44.03.33.64.53.83.53.4
Rainfall (in)Rain days
Jan3.59
Feb2.68
Mar3.28
Apr3.39
May3.410
Jun4.012
Jul3.312
Aug3.612
Sep4.513
Oct3.89
Nov3.59
Dec3.49

Clouds and sunshine

ClearMostly clearPartly cloudyMostly cloudyOvercast

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

In Bay City, 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 September 6 and lasts for 2.3 months, ending around November 14. The clearest month is October, when the sky is clear, mostly clear, or partly cloudy 69% of the time on average.

The cloudier part of the year begins around November 15 and lasts for 5.6 months, ending around May 3. The cloudiest month is January, when it is overcast or mostly cloudy 56% 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%JanFebMarAprMayJunJulAugSepOctNovDecOct 3 · 71%Feb 2 · 42%clearmostly clearpartly cloudymostly cloudyovercastcloudierclearercloudier
Clearer (%)Cloudier (%)
Jan4456
Feb4555
Mar4852
Apr5347
May6139
Jun6535
Jul5941
Aug5842
Sep6139
Oct6931
Nov5644
Dec4753

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 20, brings about 13 h 54 min of light; the shortest, around December 20, only 10 h 06 min — a swing of roughly 3 h 48 min.

12 AM4 AM8 AM12 PM4 PM8 PM12 AMJanFebMarAprMayJunJulAugSepOctNovDec
Daylight (h)Sunrise (AM)Sunset (PM)
Jan10.47:235:43
Feb11.07:106:07
Mar11.86:406:27
Apr12.76:036:45
May13.45:377:03
Jun13.85:297:19
Jul13.75:397:20
Aug13.05:576:59
Sep12.26:136:23
Oct11.36:305:48
Nov10.66:535:25
Dec10.27:155:25

Sunny days

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

Bay City averages about 12 sunny days a month — counting the days the sky stays clear or mostly clear — with a clear seasonal swing between 9 and 16 days.

The sunnier stretch runs 2.3 months, from around Sep 11 to Nov 20. The sunniest month is October, with roughly 16 sunny days (bright).

The greyest month is March, down near 10 sunny days — about 37% fewer than the October peak.

05101520JanFebMarAprMayJunJulAugSepOctNovDecgreyersunniergreyergloomymixedbrightOct 316 daysMar 19 days
Sunny daysSky
Jan10Mixed
Feb9Mixed
Mar10Mixed
Apr11Mixed
May12Mixed
Jun13Mixed
Jul13Mixed
Aug12Mixed
Sep13Mixed
Oct16Bright
Nov12Mixed
Dec10Mixed

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 Bay City, how humid it feels changes dramatically over the year.

The more humid part of the year lasts 6.1 months, from around April 18 to October 19. The muggiest month is July, when the air feels humid, muggy or worse about 100% of the time.

The most comfortable stretch runs from around October 20 to April 17, and January is the most comfortable month — the air is dry or comfortable 82% of the time.

0%10%20%30%40%50%60%70%80%90%100%JanFebMarAprMayJunJulAugSepOctNovDecJan 7 · 83%Jul 12 · 0%miserablemuggyhumidcomfortableoppressivedrycomfortablehumidcomfortable
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
Jan711111600
Feb6014151100
Mar4315202110
Apr24141931120
May761029453
Jun012116323
Jul00126136
Aug00155836
Sep548154721
Oct23121620254
Nov4616161660
Dec6512101110

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 Bay City is typically light breeze, near 8 mph, and varies moderately with the seasons.

The windier part of the year lasts 7.0 months, from around Oct 29 to May 28. The windiest month is April, averaging about 9 mph (light breeze).

The calmer part of the year runs from around May 29 to Oct 28, with August the calmest month at about 6 mph.

051015JanFebMarAprMayJunJulAugSepOctNovDecwindiercalmerwindiercalmlight breezebreezyApr 29 · 9 mphAug 30 · 6 mph
Wind speed (mph)Feels
Jan8light breeze
Feb8light breeze
Mar9light breeze
Apr9light breeze
May8light breeze
Jun7calm
Jul6calm
Aug6calm
Sep6calm
Oct7calm
Nov8light breeze
Dec8light breeze

Hazard calendar for Bay City

In seasonPeak

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

Bay City sits in the Atlantic hurricane belt; the season peaks August–October.

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

Best time to visit Bay City

TravelBeach/poolTemperatureCloudsPrecipitation

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

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

0246810JanFebMarAprMayJunJulAugSepOctNovDecbest timebest timetravel scoretemperaturecloudsprecipitationMar 23 · 7.4

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
Jan6.0good
Feb6.4good
Mar7.1good
Apr6.9good
May5.4fair
Jun3.8fair
Jul3.4poor
Aug3.2poor
Sep4.2fair
Oct6.5good
Nov7.0good
Dec6.3good

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 Bay City for hot-weather activities run from late March to mid August and again from mid September to mid November, with a peak score in the first week of October.

024681012JanFebMarAprMayJunJulAugSepOctNovDecbest timebest timebeach/pool scoretemperaturecloudsprecipitationOct 7 · 7.4

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 Bay City, 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 92°F), the essentials are light clothes, rain gear and sun protection. In the cold season around January (highs near 64°F), pack rain gear.

Light clothing
Warm layer
Winter coat
Rain gear
Sun protection
Windbreaker

In August, Bay City sees daytime highs around 92°F and nights near 76°F. Pack light clothes. Worth having: rain gear and sun protection. About 12 days see rain.

Sea temperature near Bay City

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 25 mi away) is warmest in August at about 85°F and coldest in February near 62°F.

It's comfortable for a long swim from Apr 1 to Dec 5 — about 8.2 months when the water holds above 68°F.

60°70°80°90°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swim
Sea temperature (°F)Comfort
Jan62Cool
Feb62Cool
Mar65Cool
Apr71Refreshing
May77Warm
Jun83Tropical
Jul85Tropical
Aug85Tropical
Sep84Tropical
Oct79Warm
Nov72Refreshing
Dec66Cool

UV index (midday) in Bay City 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 Bay City peaks around August 11 at about 11 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 21 at about 4 (moderate).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecModerateHighVery highExtremeVery highHighModerateAug 11UV 11Dec 21UV 4
UV index (midday)Level
Jan4Moderate
Feb6High
Mar7High
Apr10Very high
May10Extreme
Jun11Extreme
Jul11Extreme
Aug11Extreme
Sep9Very high
Oct7High
Nov5High
Dec4Moderate

Average hourly UV index in Bay City

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 August 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)
Jan40
Feb50
Mar62.5
Apr7.55
May86
Jun8.56
Jul8.56
Aug86
Sep74.5
Oct62
Nov4.50
Dec3.50

Air quality in Bay City 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 Bay City is worst in July — around 20 µg/m³ PM2.5 (moderate), about 2.9× the cleanest month (November, 7 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecGoodModerateGoodJul 1520 µg/m³Nov 167 µg/m³
PM2.5 (µg/m³)Level
Jan8Good
Feb8Good
Mar10Good
Apr11Good
May14Moderate
Jun17Moderate
Jul20Moderate
Aug15Moderate
Sep11Good
Oct7Good
Nov7Good
Dec7Good
Almanac & agriculture

Growing season

Chance of a frost-free day

Bay City is mild enough that a frost-free day stays more likely than not even in midwinter.

0%25%50%75%100%JanFebMarAprMayJunJulAugSepOctNovDec
Frost-free chance (%)Frost nights
Jan920
Feb960
Mar990
Apr1000
May1000
Jun1000
Jul1000
Aug1000
Sep1000
Oct1000
Nov980
Dec930

Growing degree days

Degree days (base 50°F)

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. Bay City banks about 7,661 degree days a year, and the running total — which growers use to time plantings and predict maturity — climbs fastest around August.

02,0004,0006,0008,000JanFebMarAprMayJunJulAugSepOctNovDec
Growing degree days (°F·days)
Jan171
Feb252
Mar459
Apr623
May853
Jun972
Jul1,049
Aug1,053
Sep900
Oct698
Nov409
Dec223

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.

Bay City receives about 4.7 kWh/m² a day of solar energy on average — bright — with a clear seasonal swing between 2.7 and 6.3 kWh/m².

The brighter stretch of the year lasts 6.5 months, from around Mar 19 to Oct 3. The brightest month is July, averaging about 6.3 kWh/m² (intense).

The dimmest month is December, down near 2.7 kWh/m² — roughly 56% less than the July peak.

01234567JanFebMarAprMayJunJulAugSepOctNovDecdimmerbrighterdimmerdimmoderatebrightintenseJul 166.3 kWhDec 172.7 kWh
Solar energy (kWh/m²)Level
Jan3.0Moderate
Feb3.6Moderate
Mar4.6Bright
Apr5.7Bright
May6.2Intense
Jun6.2Intense
Jul6.3Intense
Aug5.9Bright
Sep5.0Bright
Oct4.3Bright
Nov3.2Moderate
Dec2.7Moderate

Where is Bay City?

Bay City sits at 29.0°N, 96.0°W, 52 ft above sea level, in United States. The nearest listed city is Lake Jackson, 32 mi away.

Topography around Bay City

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

Within 2 miles, the terrain around Bay City has only modest variations in elevation — a maximum elevation change of 66 ft around an average of 52 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 112 ft; within 50 miles, only modest variations in elevation — a maximum elevation change of 249 ft.

The land around Bay City is covered by trees (38%) and grassland (38%) within 2 miles, grassland (47%), cropland (28%) and trees (23%) within 10 miles, and water (28%), grassland (27%) and trees (20%) within 50 miles.

2 miles
66 ft
10 miles
112 ft
50 miles
249 ft
treesgrasslandcroplandartificial surfaceswaterwetland
Nearby: Lake Jackson 32 mi · Angleton 35 mi · Rosenberg 41 mi · New Territory 46 mi · Pecan Grove 47 mi · Sugar Land 48 mi · Fresno 50 mi · Stafford 50 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 Bay City (28.9828°, -95.9694°, elevation 52 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. 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).