Porto Alegre weather in March

In March, Porto Alegre sees average daytime highs of 28°C and overnight lows near 20°C, with 112 mm of rain across 11.9 wet days and about 12.2 hours of daylight. It is the 4th-warmest and 10th-wettest month of the year here.

Highs ease over the month, from about 29°C in the first days to 27°C by the end. The sky is clear or mostly clear about 34% of the time in March, and the air most often feels muggy.

Daylight stretches from about 12 h 42 min at the start of March to 11 h 48 min by month's end. Set against the rest of the year, March is Porto Alegre's 1st-clearest and 8th-windiest month. For the whole year in context, see Porto Alegre's year-round climate.

Daytime high
28°
4th warmest
Overnight low
20°
10th coldest
Rainfall
112 mm
11.9 wet days
Daylight
12 h 12 min
7:28 AM – 7:41 PM
Cloud cover
55%
1st clearest
Wind
10 km/h
8th windiest
Solar energy
4.93 kWh/m²
Travel score
5.7
out of 10

Porto Alegre is human settlement in Brazil.

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

Temperature in March

Average highAverage lowShaded bands: 10–90% of days

Highs ease over the month, from about 29°C in the first days to 27°C by the end.

A typical March day in Porto Alegre reaches about 28°C in the afternoon and slips back to 20°C overnight — a 9°C spread between the day's warmth and the night's chill. On most days the high lands between 24°C and 33°C. Set against its neighbours, March runs about 1°C cooler than February and about 3°C warmer than April.

10°15°20°25°30°35°151015202531
Avg high (°C)Avg low (°C)
12920
22920
32920
42920
52920
62920
72920
82920
92920
102920
112920
122920
132920
142920
152920
162820
172820
182819
192819
202819
212819
222819
232819
242819
252819
262819
272819
282719
292718
302718
312718

How March really feels in Porto Alegre

Once humidity and wind are folded in, March averages 0 days that feel above 32°C and 0 that feel at or below 0°C — the comfort signal a plain temperature reading hides.

Days feeling ≥ 32°C
0
heat index over the day's high
Days feeling ≤ C
0
wind chill below the day's low

March sits comfortably in between — no days that feel dangerously hot or drop to a hard freeze once humidity and wind are folded in.

Porto Alegre weather by month

How March compares with the rest of the year at a glance. March is the 4th-warmest and 10th-wettest month here — the current month is highlighted below.

MonthHigh / Low (°C)Rainfall (mm)Wet daysDaylight (hours)Travel score
Jan30° / 21°13714.113.74.6
Feb30° / 21°12613.313.14.6
Mar28° / 20°11211.912.25.7
Apr26° / 17°1069.211.36.8
May22° / 13°1079.210.56.7
Jun20° / 11°1139.210.16.2
Jul19° / 10°1401010.36.1
Aug21° / 11°12010.210.96.5
Sep22° / 13°14611.111.86.4
Oct24° / 16°17012.512.76.4
Nov27° / 17°12310.813.56.4
Dec29° / 20°12511.713.95.2

Cloud cover in March

ClearMostly clearPartly cloudyMostly cloudyOvercast

The sky is clear or mostly clear about 34% of the time in March, the clearest month of the year.

Beyond those clear spells, partly cloudy skies cover about 19% of March, with mostly cloudy or overcast conditions the remaining 47%.

0%25%50%75%100%151015202531
Clearer (%)Cloudier (%)
14852
24951
35050
45050
55149
65149
75149
85248
95248
105347
115347
125446
135545
145545
155545
165644
175644
185644
195644
205545
215644
225644
235545
245545
255446
265446
275446
285347
295347
305347
315347

Chance of precipitation in March

Any precipitation

Porto Alegre gets around 112 mm of rain over 11.9 wet days in March. The line is the day-by-day chance of measurable precipitation.

Day to day, the chance of measurable rain averages around 39% and peaks near 45% on the wettest days. The odds ease toward the end of the month.

0%20%40%60%151015202531
Rain chance (%)
145
245
344
443
543
642
741
841
940
1040
1140
1239
1339
1439
1539
1639
1738
1838
1938
2038
2137
2237
2337
2436
2536
2635
2735
2834
2934
3033
3132

Humidity in March

DryComfortableHumidMuggyOppressiveMiserable

Most of March feels muggy — the stacked bands show each day's mix of comfort levels, read off the dew point.

By dew point, March lands in the muggy band about 39% of days. Sticky, muggy-or-worse air turns up on roughly 65% of them.

0%25%50%75%100%151015202531
Dry (%)Comfortable (%)Humid (%)Muggy (%)Oppressive (%)Miserable (%)
1051934402
2051935392
3051936391
4061936381
5062036371
6062037361
7062037351
8062138341
9062138331
10072139321
11072239311
12072239301
13172340291
14182340281
15182440270
16192440250
17192541240
181102541230
192102641210
202102641200
212112741190
222112741180
233112742170
243122842160
253122842150
263122842140
273132842130
284132842130
294142941120
304142941120
314152940110

Wind in March

Winds average 10 km/h in March.

Across March, daily wind ranges from about 10 km/h on the calmest days to 10 km/h at its breeziest. It stays fairly steady from day to day.

051015151015202531
Wind speed (km/h)Feels
110calm
210calm
310calm
410calm
510calm
610calm
710calm
810calm
910calm
1010calm
1110calm
1210calm
1310calm
1410calm
1510calm
1610calm
1710calm
1810calm
1910calm
2010calm
2110calm
2210calm
2310calm
2410calm
2510calm
2610calm
2710calm
2810calm
2910calm
3010calm
3110calm

Sunrise & sunset in March

DaylightNight

Daylight runs from about 12 h 42 min at the start of March to 11 h 48 min by month's end. The lit band spans sunrise to sunset each day.

Days shrink by about 54 minutes over March. Sunrise moves from 7:18 AM to 7:37 AM, and sunset from 7:59 PM to 7:23 PM.

12 AM4 AM8 AM12 PM4 PM8 PM12 AM151015202531
Daylight (h)Sunrise (AM)Sunset (PM)
112.77:187:59
212.77:187:58
312.67:197:56
412.67:207:55
512.67:217:54
612.57:217:53
712.57:227:52
812.57:237:51
912.47:237:50
1012.47:247:49
1112.47:257:47
1212.37:257:46
1312.37:267:45
1412.37:277:44
1512.37:277:43
1612.27:287:41
1712.27:287:40
1812.27:297:39
1912.17:307:38
2012.17:307:36
2112.17:317:35
2212.07:327:34
2312.07:327:33
2412.07:337:31
2511.97:337:30
2611.97:347:29
2711.97:357:28
2811.97:357:26
2911.87:367:25
3011.87:377:24
3111.87:377:23

Solar energy in March

Daily solar energy (kWh/m²)

Average shortwave solar energy reaching the ground each day in March, about 4.93 kWh/m².

For context, solar energy here swings from a low near 2.39 kWh/m² to a high of 6.58 kWh/m² in December across the year — March's 4.93 kWh/m² falls in the middle.

0246151015202531
Solar energy (kWh/m²)Level
15.3Bright
25.3Bright
35.3Bright
45.3Bright
55.3Bright
65.3Bright
75.2Bright
85.2Bright
95.2Bright
105.2Bright
115.1Bright
125.1Bright
135.1Bright
145.0Bright
155.0Bright
165.0Bright
174.9Bright
184.9Bright
194.8Bright
204.8Bright
214.8Bright
224.7Bright
234.7Bright
244.6Bright
254.6Bright
264.6Bright
274.5Bright
284.5Bright
294.5Bright
304.4Bright
314.4Bright
Planning a trip in March

Is March a good time to visit Porto Alegre?

Our two travel scores rate March for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).

5.7
Sightseeing
9th-best month of the year
6.6
Beach & pool
2nd-best month of the year

March is a reasonable time to visit Porto Alegre for sightseeing. The water and warmth also suit a beach or pool day.

What to pack for Porto Alegre in March

From March's temperature range, rain chance, sun and wind — what's worth putting in the bag.

In March, Porto Alegre sees daytime highs around 28°C and nights near 20°C. Pack light clothes. Worth having: rain gear and sun protection. About 12 days see rain.

light clothesrain gearsun protection

Sea temperature near Porto Alegre in March

The nearest coast averages about 25°C in March — the other half of the beach question. The full-year curve and swim-comfort zones are below.

The sea at the nearest coast (about 39 km away) is warmest in February at about 26°C and coldest in July near 15°C.

It's comfortable for a long swim from Oct 23 to May 10 — about 6.6 months when the water holds above 20°C.

15°20°25°JanFebMarAprMayJunJulAugSepOctNovDecbracingcoolrefreshingwarmtropicalcomfortable to swimcomfortable to swim
Sea temperature (°C)Comfort
Jan26Warm
Feb26Warm
Mar25Warm
Apr23Refreshing
May19Cool
Jun17Cool
Jul15Cool
Aug16Cool
Sep17Cool
Oct20Cool
Nov22Refreshing
Dec24Warm

UV index in Porto Alegre in March

LowModerateHighVery highExtreme

Clear-sky midday UV in March peaks around 10 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.

Under clear skies, the midday UV index in Porto Alegre peaks around January 15 at about 13 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near June 19 at about 3 (moderate).

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

025710JanFebMarAprMayJunJulAugSepOctNovDecExtremeVery highModerateVery highExtremeJan 15UV 13Jun 19UV 3
UV index (midday)Level
Jan13Extreme
Feb12Extreme
Mar10Very high
Apr7Very high
May4Moderate
Jun3Moderate
Jul4Moderate
Aug5Moderate
Sep8Very high
Oct8Very high
Nov11Extreme
Dec12Extreme

Air quality in Porto Alegre in March

GoodModeratePoorUnhealthyVery unhealthy

Average fine-particle pollution (PM2.5) through the year — so you can see where March falls, not just the annual average.

Air quality in Porto Alegre is worst in August — around 27 µg/m³ PM2.5 (moderate), about 2.1× the cleanest month (December, 13 µg/m³).

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

0102030JanFebMarAprMayJunJulAugSepOctNovDecModerateAug 1327 µg/m³Dec 2213 µg/m³
PM2.5 (µg/m³)Level
Jan13Moderate
Feb13Moderate
Mar15Moderate
Apr18Moderate
May21Moderate
Jun23Moderate
Jul25Moderate
Aug27Moderate
Sep23Moderate
Oct16Moderate
Nov15Moderate
Dec13Moderate
Location & terrain

Where is Porto Alegre?

Porto Alegre sits at 30.0°S, 51.2°W, 46 m above sea level, in Brazil. The nearest listed city is Guaíba, 13 km away.

Topography around Porto Alegre

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

Within 3 km, the terrain around Porto Alegre has only modest variations in elevation — a maximum elevation change of 86 m around an average of 9 m above sea level; within 16 km, significant variations in elevation — a maximum elevation change of 311 m; within 80 km, large variations in elevation — a maximum elevation change of 883 m.

The land around Porto Alegre is covered by artificial surfaces (42%) and water (35%) within 3 km, artificial surfaces (29%) and trees (26%) within 16 km, and trees (43%) and grassland (21%) within 80 km.

3 km
86 m
16 km
311 m
80 km
883 m
treesgrasslandcroplandartificial surfaceswaterwetland
March weather nearby: Guaíba 13 km · Canoas 14 km · Alvorada 15 km · Cachoeirinha 16 km · Esteio 20 km · Nova Santa Rita 21 km · Viamão 21 km · Gravataí 25 km

Brazil travel facts

Travel advisory
Level 2
Exercise Increased Caution
Power plugs
Type C / N
127 / 220 V · 60 Hz
Prices
≈ 46% of US
price level, 2025
GDP per capita
$10,713
2025
Happiness
6.6 / 10
World Happiness, 2025
Safe drinking water
89%
of population, 2024
Homicide rate
19.3
per 100k, 2023
Road deaths
16
per 100k/yr, 2019
Income group
Upper middle
World Bank
English
Low
EF EPI 482
Religion
Roman Catholic 57%Evangelical 27%none 9%other 4%

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 Porto Alegre (-30.0328°, -51.2302°, elevation 46 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. 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).