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Average Weather in January in Stellenbosch South Africa

Daily high temperatures are around 81°F, rarely falling below 72°F or exceeding 92°F. The highest daily average high temperature is 82°F on January 27.

Daily low temperatures are around 60°F, rarely falling below 54°F or exceeding 65°F. The highest daily average low temperature is 61°F on January 29.

For reference, on January 26, the hottest day of the year, temperatures in Stellenbosch typically range from 61°F to 82°F, while on July 11, the coldest day of the year, they range from 43°F to 62°F.

Average High and Low Temperature in January

The daily average high (red line) and low (blue line) temperature, with 25th to 75th and 10th to 90th percentile bands. The thin dotted lines are the corresponding average perceived temperatures.

The figure below shows you a compact characterization of the hourly average temperatures for the quarter of the year centered on January. 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 January

Average Hourly Temperature in January in Stellenbosch18152229112233445566778899101011111212131314141515161617171818191920202121222223232424252526262727282829293030313112 AM4 AM8 AM12 PM4 PM8 PM12 AMDecFebcoolcoolcomfortablecomfortablewarmcomfortable
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 average hourly temperature, color coded into bands. The shaded overlays indicate night and civil twilight.

San Jose, California, United States (10,248 miles away) and Canguçu, Brazil (4,081 miles) are the far-away foreign places with temperatures most similar to Stellenbosch (view comparison).

Clouds

The month of January in Stellenbosch experiences gradually decreasing cloud cover, with the percentage of time that the sky is overcast or mostly cloudy decreasing from 18% to 12%.

The clearest day of the month is January 30, with clear, mostly clear, or partly cloudy conditions 88% of the time.

For reference, on May 18, the cloudiest day of the year, the chance of overcast or mostly cloudy conditions is 44%, while on February 10, the clearest day of the year, the chance of clear, mostly clear, or partly cloudy skies is 89%.

Cloud Cover Categories in January

Cloud Cover Categories in January in Stellenbosch1815222911223344556677889910101111121213131414151516161717181819192020212122222323242425252626272728282929303031310%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%DecFebJan 182%Jan 182%Jan 3188%Jan 3188%Jan 1185%Jan 1185%Jan 2187%Jan 2187%clearmostly clearovercastpartly cloudymostly cloudy
0% clear 20% mostly clear 40% partly cloudy 60% mostly cloudy 80% overcast 100%
The percentage of time spent in each cloud cover band, categorized by the percentage of the sky covered by clouds.

Precipitation

A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. In Stellenbosch, the chance of a wet day over the course of January is gradually decreasing, starting the month at 10% and ending it at 6%.

For reference, the year's highest daily chance of a wet day is 28% on July 20, and its lowest chance is 6% on February 11.

Probability of Precipitation in January

The percentage of days in which various types of precipitation are observed, excluding trace quantities: rain alone, snow alone, and mixed (both rain and snow fell in the same day).

Rainfall

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 January in Stellenbosch is essentially constant, remaining about 0.7 inches throughout, and rarely exceeding 2.3 inches or falling below -0.0 inches.

Average Monthly Rainfall in January

The average rainfall (solid line) accumulated over the course of a sliding 31-day period centered on the day in question, with 25th to 75th and 10th to 90th percentile bands. The thin dotted line is the corresponding average liquid-equivalent snowfall.

Sun

Over the course of January in Stellenbosch, the length of the day is decreasing. From the start to the end of the month, the length of the day decreases by 36 minutes, implying an average daily decrease of 1 minute, 13 seconds, and weekly decrease of 8 minutes, 30 seconds.

The shortest day of the month is January 31, with 13 hours, 46 minutes of daylight and the longest day is January 1, with 14 hours, 22 minutes of daylight.

Hours of Daylight and Twilight in January

Hours of Daylight and Twilight in January in Stellenbosch1815222911223344556677889910101111121213131414151516161717181819192020212122222323242425252626272728282929303031310 hr24 hr4 hr20 hr8 hr16 hr12 hr12 hr16 hr8 hr20 hr4 hr24 hr0 hrDecFebdaydaydaydaynightJan 114 hr, 22 minJan 114 hr, 22 minJan 3113 hr, 46 minJan 3113 hr, 46 min
The number of hours during which the Sun is visible (black line). From bottom (most yellow) to top (most gray), the color bands indicate: full daylight, twilight (civil, nautical, and astronomical), and full night.

The earliest sunrise of the month in Stellenbosch is 5:36 AM on January 1 and the latest sunrise is 28 minutes later at 6:04 AM on January 31.

The latest sunset is 7:59 PM on January 7 and the earliest sunset is 9 minutes earlier at 7:50 PM on January 31.

Daylight saving time is not observed in Stellenbosch during 2018.

For reference, on December 21, the longest day of the year, the Sun rises at 5:29 AM and sets 14 hours, 25 minutes later, at 7:55 PM, while on June 21, the shortest day of the year, it rises at 7:49 AM and sets 9 hours, 54 minutes later, at 5:43 PM.

Sunrise & Sunset with Twilight in January

Sunrise & Sunset with Twilight in January in Stellenbosch1815222911223344556677889910101111121213131414151516161717181819192020212122222323242425252626272728282929303031312 AM4 AM6 AM8 AM10 AM12 PM2 PM4 PM6 PM8 PM10 PM12 AMDecFeb5:36 AM5:36 AMJan 17:59 PMJan 17:59 PM6:04 AM6:04 AMJan 317:50 PMJan 317:50 PM5:50 AM5:50 AMJan 167:58 PMJan 167:58 PMSolarMidnightSolarMidnightSolarNoonSunriseSunset
The solar day over the course of January. From bottom to top, the black lines are the previous solar midnight, sunrise, solar noon, sunset, and the next solar midnight. The day, twilights (civil, nautical, and astronomical), and night are indicated by the color bands from yellow to gray.

Humidity

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 Stellenbosch is essentially constant during January, remaining around 2% throughout.

For reference, on February 15, the muggiest day of the year, there are muggy conditions 2% of the time, while on May 4, the least muggy day of the year, there are muggy conditions 0% of the time.

Humidity Comfort Levels in January

Humidity Comfort Levels in January in Stellenbosch1815222911223344556677889910101111121213131414151516161717181819192020212122222323242425252626272728282929303031310%10%20%30%40%50%60%70%80%90%100%DecFebJan 11%Jan 11%Jan 312%Jan 312%Jan 112%Jan 112%Jan 212%Jan 212%humidhumidcomfortablecomfortabledrydrymuggymuggy
dry 55°F comfortable 60°F humid 65°F muggy 70°F oppressive 75°F miserable
The percentage of time spent at various humidity comfort levels, categorized by dew point.

Wind

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 Stellenbosch is essentially constant during January, remaining within 0.2 miles per hour of 11.7 miles per hour throughout.

For reference, on January 22, the windiest day of the year, the daily average wind speed is 11.8 miles per hour, while on May 3, the calmest day of the year, the daily average wind speed is 8.9 miles per hour.

The highest daily average wind speed during January is 11.8 miles per hour on January 22.

Average Wind Speed in January

The average of mean hourly wind speeds (dark gray line), with 25th to 75th and 10th to 90th percentile bands.
The hourly average wind direction in Stellenbosch throughout January is predominantly from the south, with a peak proportion of 51% on January 9.

Wind Direction in January

Wind Direction in January in Stellenbosch1815222911223344556677889910101111121213131414151516161717181819192020212122222323242425252626272728282929303031310%100%20%80%40%60%60%40%80%20%100%0%DecFebwestsoutheast
northeastsouthwest
The percentage of hours in which the mean wind direction is from each of the four cardinal wind directions, excluding hours in which the mean wind speed is less than 1.0 mph. The lightly tinted areas at the boundaries are the percentage of hours spent in the implied intermediate directions (northeast, southeast, southwest, and northwest).

Water Temperature

Stellenbosch 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 Stellenbosch is essentially constant during January, remaining around 66°F throughout.

Average Water Temperature in January

The daily average water temperature (purple line), with 25th to 75th and 10th to 90th percentile bands.

Growing Season

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).

The growing season in Stellenbosch typically lasts for 12 months (362 days), from around July 17 to around July 14, rarely starting after August 25, or ending before June 8.

The month of January in Stellenbosch is reliably fully within the growing season.

Time Spent in Various Temperature Bands and the Growing Season in January

Time Spent in Various Temperature Bands and the Growing Season in January in Stellenboschgrowing seasongrowing season1815222911223344556677889910101111121213131414151516161717181819192020212122222323242425252626272728282929303031310%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%DecFeb100%Jan 16100%Jan 16coolcomfortablewarmhotcold
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 percentage of time spent in various temperature bands. The black line is the percentage chance that a given day is within the growing season.

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 Stellenbosch are rapidly increasing during January, increasing by 601°F, from 1,879°F to 2,480°F, over the course of the month.

Growing Degree Days in January

The average growing degree days accumulated over the course of January, with 25th to 75th and 10th to 90th percentile bands.

Solar Energy

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 Stellenbosch is essentially constant during January, remaining within 0.2 kWh of 8.5 kWh throughout.

The highest average daily incident shortwave solar energy during January is 8.8 kWh on January 9.

Average Daily Incident Shortwave Solar Energy in January

Average Daily Incident Shortwave Solar Energy in January in Stellenbosch1815222911223344556677889910101111121213131414151516161717181819192020212122222323242425252626272728282929303031310 kWh1 kWh2 kWh3 kWh4 kWh5 kWh6 kWh7 kWh8 kWh9 kWh10 kWhDecFebJan 98.8 kWhJan 98.8 kWhJan 318.3 kWhJan 318.3 kWh
The average daily shortwave solar energy reaching the ground per square meter (orange line), with 25th to 75th and 10th to 90th percentile bands.

Topography

For the purposes of this report, the geographical coordinates of Stellenbosch are -33.935 deg latitude, 18.867 deg longitude, and 561 ft elevation.

The topography within 2 miles of Stellenbosch contains very significant variations in elevation, with a maximum elevation change of 1,785 feet and an average elevation above sea level of 541 feet. Within 10 miles contains very significant variations in elevation (5,253 feet). Within 50 miles also contains extreme variations in elevation (6,837 feet).

The area within 2 miles of Stellenbosch is covered by artificial surfaces (55%) and cropland (39%), within 10 miles by cropland (74%) and shrubs (16%), and within 50 miles by water (38%) and cropland (33%).

Data Sources

This report illustrates the typical weather in Stellenbosch 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, Cape Town International Airport, in our network suitable to be used as a proxy for the historical temperature and dew point records of Stellenbosch.

At a distance of 25 kilometers from Stellenbosch, 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 Stellenbosch 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.

Other Data

All data relating to the Sun's position (e.g., sunrise and sunset) are computed using astronomical formulas from the book, Astronomical Tables of the Sun, Moon and Planets , 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.

Disclaimer

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.