October Weather in Arrentela Portugal
Daily high temperatures decrease by 7°F, from 75°F to 68°F, rarely falling below 63°F or exceeding 83°F.
Daily low temperatures decrease by 5°F, from 61°F to 56°F, rarely falling below 50°F or exceeding 65°F.
For reference, on July 29, the hottest day of the year, temperatures in Arrentela typically range from 65°F to 83°F, while on January 18, the coldest day of the year, they range from 47°F to 58°F.
Average High and Low Temperature in October in Arrentela
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 in Arrentela
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 Arrentela experiences rapidly increasing cloud cover, with the percentage of time that the sky is overcast or mostly cloudy increasing from 36% to 48%. The highest chance of overcast or mostly cloudy conditions is 48% on October 31.
The clearest day of the month is October 1, with clear, mostly clear, or partly cloudy conditions 64% of the time.
For reference, on December 14, the cloudiest day of the year, the chance of overcast or mostly cloudy conditions is 50%, while on July 20, the clearest day of the year, the chance of clear, mostly clear, or partly cloudy skies is 92%.
Cloud Cover Categories in October in Arrentela
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 Arrentela, the chance of a wet day over the course of October is very rapidly increasing, starting the month at 17% and ending it at 29%.
For reference, the year's highest daily chance of a wet day is 29% on December 3, and its lowest chance is 1% on July 31.
Probability of Precipitation in October in Arrentela
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 Arrentela is rapidly increasing, starting the month at 1.5 inches, when it rarely exceeds 3.2 inches or falls below 0.2 inches, and ending the month at 3.1 inches, when it rarely exceeds 5.9 inches or falls below 0.6 inches.
Average Monthly Rainfall in October in Arrentela
Over the course of October in Arrentela, the length of the day is rapidly decreasing. From the start to the end of the month, the length of the day decreases by 1 hour, 12 minutes, implying an average daily decrease of 2 minutes, 23 seconds, and weekly decrease of 16 minutes, 41 seconds.
The shortest day of the month is October 31, with 10 hours, 35 minutes of daylight and the longest day is October 1, with 11 hours, 47 minutes of daylight.
Hours of Daylight and Twilight in October in Arrentela
The latest sunrise of the month in Arrentela is 8:01 AM on October 30 and the earliest sunrise is 59 minutes earlier at 7:02 AM on October 31.
The latest sunset is 7:19 PM on October 1 and the earliest sunset is 1 hour, 42 minutes earlier at 5:37 PM on October 31.
Daylight saving time (DST) ends at 1:00 AM on October 31, 2021, shifting sunrise and sunset to be an hour earlier.
For reference, on June 21, the longest day of the year, the Sun rises at 6:12 AM and sets 14 hours, 52 minutes later, at 9:04 PM, while on December 21, the shortest day of the year, it rises at 7:50 AM and sets 9 hours, 28 minutes later, at 5:18 PM.
Sunrise & Sunset with Twilight and Daylight Saving Time in October in Arrentela
The figure below presents a compact representation of key lunar data for October 2021. The horizontal axis is the day, the vertical axis is the hour of the day, and the colored areas indicate when the moon is above the horizon. The vertical gray bars (new Moons) and blue bars (full Moons) indicate key Moon phases. The label associated with each bar indicates the date and time that the phase is obtained, and the companion time labels indicate the rise and set times of the Moon for the nearest time interval in which the moon is above the horizon.
Moon Rise, Set & Phases in October in Arrentela
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 Arrentela is decreasing during October, falling from 13% to 6% over the course of the month.
For reference, on August 16, the muggiest day of the year, there are muggy conditions 19% of the time, while on January 9, the least muggy day of the year, there are muggy conditions 0% of the time.
Humidity Comfort Levels in October in Arrentela
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 Arrentela is gradually increasing during October, increasing from 9.9 miles per hour to 10.9 miles per hour over the course of the month.
For reference, on December 15, the windiest day of the year, the daily average wind speed is 12.1 miles per hour, while on September 17, the calmest day of the year, the daily average wind speed is 9.7 miles per hour.
Average Wind Speed in October in Arrentela
The hourly average wind direction in Arrentela throughout October is predominantly from the north, with a peak proportion of 48% on October 1.
Wind Direction in October in Arrentela
Arrentela 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 Arrentela is essentially constant during October, remaining within 1°F of 65°F throughout.
Average Water Temperature in October in Arrentela
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 Arrentela 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 in Arrentela
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 Arrentela are increasing during October, increasing by 425°F, from 3,640°F to 4,064°F, over the course of the month.
Growing Degree Days in October in Arrentela
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 Arrentela is rapidly decreasing during October, falling by 1.6 kWh, from 4.7 kWh to 3.1 kWh, over the course of the month.
Average Daily Incident Shortwave Solar Energy in October in Arrentela
For the purposes of this report, the geographical coordinates of Arrentela are 38.617 deg latitude, -9.100 deg longitude, and 75 ft elevation.
The topography within 2 miles of Arrentela contains only modest variations in elevation, with a maximum elevation change of 184 feet and an average elevation above sea level of 72 feet. Within 10 miles contains only modest variations in elevation (817 feet). Within 50 miles contains significant variations in elevation (2,215 feet).
The area within 2 miles of Arrentela is covered by artificial surfaces (56%), trees (21%), and cropland (12%), within 10 miles by artificial surfaces (29%) and water (29%), and within 50 miles by water (49%) and cropland (23%).
This report illustrates the typical weather in Arrentela, 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 are 2 weather stations near enough to contribute to our estimation of the temperature and dew point in Arrentela.
For each station, the records are corrected for the elevation difference between that station and Arrentela according to the International Standard Atmosphere , and by the relative change present in the MERRA-2 satellite-era reanalysis between the two locations.
The estimated value at Arrentela is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Arrentela and a given station.
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 airports 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.