Average Weather in October in Porto Alegre Brazil
Daily high temperatures increase by 5°F, from 73°F to 79°F, rarely falling below 65°F or exceeding 88°F.
Daily low temperatures increase by 4°F, from 58°F to 62°F, rarely falling below 50°F or exceeding 68°F.
For reference, on January 20, the hottest day of the year, temperatures in Porto Alegre typically range from 70°F to 86°F, while on July 21, the coldest day of the year, they range from 50°F to 66°F.
Average High and Low Temperature in October
The figure below shows you a compact characterization of the hourly average temperatures for the quarter of the year centered on October. The horizontal axis is the day, the vertical axis is the hour of the day, and the color is the average temperature for that hour and day.
Average Hourly Temperature in October
frigid 15°F freezing 32°F very cold 45°F cold 55°F cool 65°F comfortable 75°F warm 85°F hot 95°F sweltering
The month of October in Porto Alegre experiences essentially constant cloud cover, with the percentage of time that the sky is overcast or mostly cloudy remaining about 43% throughout the month.
The clearest day of the month is October 31, with clear, mostly clear, or partly cloudy conditions 59% of the time.
For reference, on June 21, the cloudiest day of the year, the chance of overcast or mostly cloudy conditions is 51%, while on March 15, the clearest day of the year, the chance of clear, mostly clear, or partly cloudy skies is 66%.
Cloud Cover Categories in October
0% clear 20% mostly clear 40% partly cloudy 60% mostly cloudy 80% overcast 100%
A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. In Porto Alegre, the chance of a wet day over the course of October is essentially constant, remaining around 34% throughout.
For reference, the year's highest daily chance of a wet day is 44% on February 9, and its lowest chance is 27% on May 17.
Probability of Precipitation in October
To show variation within the month and not just the monthly total, we show the rainfall accumulated over a sliding 31-day period centered around each day.
The average sliding 31-day rainfall during October in Porto Alegre is decreasing, starting the month at 5.4 inches, when it rarely exceeds 9.4 inches or falls below 2.4 inches, and ending the month at 4.7 inches, when it rarely exceeds 8.0 inches or falls below 1.9 inches.
Average Monthly Rainfall in October
Over the course of October in Porto Alegre, the length of the day is increasing. From the start to the end of the month, the length of the day increases by 52 minutes, implying an average daily increase of 1 minute, 45 seconds, and weekly increase of 12 minutes, 13 seconds.
The shortest day of the month is October 1, with 12 hours, 24 minutes of daylight and the longest day is October 31, with 13 hours, 16 minutes of daylight.
Hours of Daylight and Twilight in October
The earliest sunrise of the month in Porto Alegre is 5:44 AM on October 17 and the latest sunrise is 59 minutes later at 6:43 AM on October 18.
The earliest sunset is 6:26 PM on October 1 and the latest sunset is 1 hour, 20 minutes later at 7:46 PM on October 31.
Daylight saving time (DST) starts at 1:00 AM on October 18, 2020, shifting sunrise and sunset to be an hour later.
For reference, on December 21, the longest day of the year, the Sun rises at 6:20 AM and sets 14 hours, 5 minutes later, at 8:25 PM, while on June 20, the shortest day of the year, it rises at 7:20 AM and sets 10 hours, 13 minutes later, at 5:32 PM.
Sunrise & Sunset with Twilight and Daylight Saving Time in October
We base the humidity comfort level on the dew point, as it determines whether perspiration will evaporate from the skin, thereby cooling the body. Lower dew points feel drier and higher dew points feel more humid. Unlike temperature, which typically varies significantly between night and day, dew point tends to change more slowly, so while the temperature may drop at night, a muggy day is typically followed by a muggy night.
The chance that a given day will be muggy in Porto Alegre is rapidly increasing during October, rising from 15% to 32% over the course of the month.
For reference, on February 12, the muggiest day of the year, there are muggy conditions 79% of the time, while on July 31, the least muggy day of the year, there are muggy conditions 2% of the time.
Humidity Comfort Levels in October
dry 55°F comfortable 60°F humid 65°F muggy 70°F oppressive 75°F miserable
This section discusses the wide-area hourly average wind vector (speed and direction) at 10 meters above the ground. The wind experienced at any given location is highly dependent on local topography and other factors, and instantaneous wind speed and direction vary more widely than hourly averages.
The average hourly wind speed in Porto Alegre is essentially constant during October, remaining within 0.1 miles per hour of 8.5 miles per hour throughout.
For reference, on October 19, the windiest day of the year, the daily average wind speed is 8.6 miles per hour, while on June 16, the calmest day of the year, the daily average wind speed is 7.0 miles per hour.
The highest daily average wind speed during October is 8.6 miles per hour on October 19.
Average Wind Speed in October
The hourly average wind direction in Porto Alegre throughout October is predominantly from the east, with a peak proportion of 50% on October 10.
Wind Direction in October
Porto Alegre is located near a large body of water (e.g., ocean, sea, or large lake). This section reports on the wide-area average surface temperature of that water.
The average surface water temperature in Porto Alegre is increasing during October, rising by 4°F, from 64°F to 68°F, over the course of the month.
Average Water Temperature in October
Definitions of the growing season vary throughout the world, but for the purposes of this report, we define it as the longest continuous period of non-freezing temperatures (≥ 32°F) in the year (the calendar year in the Northern Hemisphere, or from July 1 until June 30 in the Southern Hemisphere).
Temperatures in Porto Alegre are sufficiently warm year round that it is not entirely meaningful to discuss the growing season in these terms. We nevertheless include the chart below as an illustration of the distribution of temperatures experienced throughout the year.
Time Spent in Various Temperature Bands and the Growing Season in October
frigid 15°F freezing 32°F very cold 45°F cold 55°F cool 65°F comfortable 75°F warm 85°F hot 95°F sweltering
Growing degree days are a measure of yearly heat accumulation used to predict plant and animal development, and defined as the integral of warmth above a base temperature, discarding any excess above a maximum temperature. In this report, we use a base of 50°F and a cap of 86°F.
The average accumulated growing degree days in Porto Alegre are rapidly increasing during October, increasing by 521°F, from 985°F to 1,506°F, over the course of the month.
Growing Degree Days in October
This section discusses the total daily incident shortwave solar energy reaching the surface of the ground over a wide area, taking full account of seasonal variations in the length of the day, the elevation of the Sun above the horizon, and absorption by clouds and other atmospheric constituents. Shortwave radiation includes visible light and ultraviolet radiation.
The average daily incident shortwave solar energy in Porto Alegre is increasing during October, rising by 1.3 kWh, from 5.2 kWh to 6.5 kWh, over the course of the month.
Average Daily Incident Shortwave Solar Energy in October
For the purposes of this report, the geographical coordinates of Porto Alegre are -30.033 deg latitude, -51.230 deg longitude, and 20 ft elevation.
The topography within 2 miles of Porto Alegre contains only modest variations in elevation, with a maximum elevation change of 292 feet and an average elevation above sea level of 33 feet. Within 10 miles contains only modest variations in elevation (1,053 feet). Within 50 miles contains very significant variations in elevation (2,933 feet).
The area within 2 miles of Porto Alegre is covered by water (33%), artificial surfaces (20%), trees (15%), and grassland (15%), within 10 miles by shrubs (25%) and trees (23%), and within 50 miles by trees (35%) and water (21%).
This report illustrates the typical weather in Porto Alegre year round, based on a statistical analysis of historical hourly weather reports and model reconstructions from January 1, 1980 to December 31, 2016.
Temperature and Dew Point
There is only a single weather station, Salgado Filho International Airport, in our network suitable to be used as a proxy for the historical temperature and dew point records of Porto Alegre.
At a distance of 7 kilometers from Porto Alegre, closer than our threshold of 150 kilometers, this station is deemed sufficiently nearby to be relied upon as our primary source for temperature and dew point records.
The station records are corrected for the elevation difference between the station and Porto Alegre according to the International Standard Atmosphere , and by the relative change present in the MERRA-2 satellite-era reanalysis between the two locations.
Please note that the station records themselves may additionally have been back-filled using other nearby stations or the MERRA-2 reanalysis.
All data relating to the Sun's position (e.g., sunrise and sunset) are computed using astronomical formulas from the book, Astronomical Algorithms 2nd Edition , by Jean Meeus.
All other weather data, including cloud cover, precipitation, wind speed and direction, and solar flux, come from NASA's MERRA-2 Modern-Era Retrospective Analysis . This reanalysis combines a variety of wide-area measurements in a state-of-the-art global meteorological model to reconstruct the hourly history of weather throughout the world on a 50-kilometer grid.
Land Use data comes from the Global Land Cover SHARE database , published by the Food and Agriculture Organization of the United Nations.
Elevation data comes from the Shuttle Radar Topography Mission (SRTM) , published by NASA's Jet Propulsion Laboratory.
Names, locations, and time zones of places and some airports come from the GeoNames Geographical Database .
Time zones for aiports and weather stations are provided by AskGeo.com .
Maps are © Esri, with data from National Geographic, Esri, DeLorme, NAVTEQ, UNEP-WCMC, USGS, NASA, ESA, METI, NRCAN, GEBCO, NOAA, and iPC.
The information on this site is provided as is, without any assurances as to its accuracy or suitability for any purpose. Weather data is prone to errors, outages, and other defects. We assume no responsibility for any decisions made on the basis of the content presented on this site.
We draw particular cautious attention to our reliance on the MERRA-2 model-based reconstructions for a number of important data series. While having the tremendous advantages of temporal and spatial completeness, these reconstructions: (1) are based on computer models that may have model-based errors, (2) are coarsely sampled on a 50 km grid and are therefore unable to reconstruct the local variations of many microclimates, and (3) have particular difficulty with the weather in some coastal areas, especially small islands.
We further caution that our travel scores are only as good as the data that underpin them, that weather conditions at any given location and time are unpredictable and variable, and that the definition of the scores reflects a particular set of preferences that may not agree with those of any particular reader.