Climate and Average Weather Year Round in La Rioja Argentina

In La Rioja, the summers are hot and humid; the winters are short, cold, and dry; and it is mostly clear year round. Over the course of the year, the temperature typically varies from 41°F to 94°F and is rarely below 32°F or above 102°F.

Based on the tourism score, the best times of year to visit La Rioja for warm-weather activities are from early March to late April and from mid September to late November.

The hot season lasts for 3.9 months, from November 1 to February 29, with an average daily high temperature above 88°F. The hottest month of the year in La Rioja is December, with an average high of 93°F and low of 70°F.

The cool season lasts for 2.8 months, from May 16 to August 11, with an average daily high temperature below 70°F. The coldest month of the year in La Rioja is July, with an average low of 41°F and high of 66°F.

In La Rioja, the average percentage of the sky covered by clouds experiences mild seasonal variation over the course of the year.

The clearer part of the year in La Rioja begins around July 30 and lasts for 9.0 months, ending around April 29.

The clearest month of the year in La Rioja is March, during which on average the sky is clear, mostly clear, or partly cloudy 84% of the time.

The cloudier part of the year begins around April 29 and lasts for 3.0 months, ending around July 30.

The cloudiest month of the year in La Rioja is June, during which on average the sky is overcast or mostly cloudy 33% of the time.

A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. The chance of wet days in La Rioja varies throughout the year.

The wetter season lasts 4.0 months, from November 23 to March 23, with a greater than 16% chance of a given day being a wet day. The month with the most wet days in La Rioja is January, with an average of 9.4 days with at least 0.04 inches of precipitation.

The drier season lasts 8.0 months, from March 23 to November 23. The month with the fewest wet days in La Rioja is August, with an average of 0.5 days with at least 0.04 inches of precipitation.

Among wet days, we distinguish between those that experience rain alone, snow alone, or a mixture of the two. The month with the most days of rain alone in La Rioja is January, with an average of 9.4 days. Based on this categorization, the most common form of precipitation throughout the year is rain alone, with a peak probability of 31% on January 6.

Rainfall

To show variation within the months and not just the monthly totals, we show the rainfall accumulated over a sliding 31-day period centered around each day of the year. La Rioja experiences significant seasonal variation in monthly rainfall.

The rainy period of the year lasts for 6.5 months, from October 12 to April 28, with a sliding 31-day rainfall of at least 0.5 inches. The month with the most rain in La Rioja is January, with an average rainfall of 2.9 inches.

The rainless period of the year lasts for 5.5 months, from April 28 to October 12. The month with the least rain in La Rioja is July, with an average rainfall of 0.1 inches.

The length of the day in La Rioja varies significantly over the course of the year. In 2024, the shortest day is June 20, with 10 hours, 16 minutes of daylight; the longest day is December 21, with 14 hours, 2 minutes of daylight.

The earliest sunrise is at 6:19 AM on December 2, and the latest sunrise is 2 hours, 3 minutes later at 8:22 AM on June 30. The earliest sunset is at 6:35 PM on June 9, and the latest sunset is 1 hour, 56 minutes later at 8:31 PM on January 9.

Daylight saving time (DST) is not observed in La Rioja during 2024.

The figure below presents a compact representation of key lunar data for 2024. 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.

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.

La Rioja experiences extreme seasonal variation in the perceived humidity.

The muggier period of the year lasts for 4.6 months, from November 20 to April 8, during which time the comfort level is muggy, oppressive, or miserable at least 13% of the time. The month with the most muggy days in La Rioja is January, with 15.2 days that are muggy or worse.

The month with the fewest muggy days in La Rioja is July, with 0.0 days that are muggy or worse.

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 La Rioja experiences significant seasonal variation over the course of the year.

The windier part of the year lasts for 6.1 months, from September 6 to March 11, with average wind speeds of more than 7.1 miles per hour. The windiest month of the year in La Rioja is November, with an average hourly wind speed of 9.2 miles per hour.

The calmer time of year lasts for 5.9 months, from March 11 to September 6. The calmest month of the year in La Rioja is June, with an average hourly wind speed of 5.0 miles per hour.

The predominant average hourly wind direction in La Rioja is from the east throughout the year.

To characterize how pleasant the weather is in La Rioja throughout the year, we compute two travel scores.

The tourism score favors clear, rainless days with perceived temperatures between 65°F and 80°F. Based on this score, the best times of year to visit La Rioja for general outdoor tourist activities are from early March to late April and from mid September to late November, with a peak score in the last week of March.

The beach/pool score favors clear, rainless days with perceived temperatures between 75°F and 90°F. Based on this score, the best time of year to visit La Rioja for hot-weather activities is from late October to mid March, with a peak score in the first week of December.

Methodology

For each hour between 8:00 AM and 9:00 PM of each day in the analysis period (1980 to 2016), independent scores are computed for perceived temperature, cloud cover, and total precipitation. Those scores are combined into a single hourly composite score, which is then aggregated into days, averaged over all the years in the analysis period, and smoothed.

Our cloud cover score is 10 for fully clear skies, falling linearly to 9 for mostly clear skies, and to 1 for fully overcast skies.

Our precipitation score, which is based on the three-hour precipitation centered on the hour in question, is 10 for no precipitation, falling linearly to 9 for trace precipitation, and to 0 for 0.04 inches of precipitation or more.

Our tourism temperature score is 0 for perceived temperatures below 50°F, rising linearly to 9 for 65°F, to 10 for 75°F, falling linearly to 9 for 80°F, and to 1 for 90°F or hotter.

Our beach/pool temperature score is 0 for perceived temperatures below 65°F, rising linearly to 9 for 75°F, to 10 for 82°F, falling linearly to 9 for 90°F, and to 1 for 100°F or hotter.

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 La Rioja typically lasts for 11 months (342 days), from around July 18 to around June 24, rarely starting after August 25, or ending before May 30.

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.

Based on growing degree days alone, the first spring blooms in La Rioja should appear around July 19, only rarely appearing before July 14 or after July 27.

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 experiences significant seasonal variation over the course of the year.

The brighter period of the year lasts for 3.6 months, from October 20 to February 8, with an average daily incident shortwave energy per square meter above 7.3 kWh. The brightest month of the year in La Rioja is December, with an average of 8.2 kWh.

The darker period of the year lasts for 3.3 months, from April 30 to August 6, with an average daily incident shortwave energy per square meter below 4.5 kWh. The darkest month of the year in La Rioja is June, with an average of 3.6 kWh.

For the purposes of this report, the geographical coordinates of La Rioja are -29.411 deg latitude, -66.851 deg longitude, and 1,647 ft elevation.

The topography within 2 miles of La Rioja contains only modest variations in elevation, with a maximum elevation change of 433 feet and an average elevation above sea level of 1,668 feet. Within 10 miles contains only modest variations in elevation (6,191 feet). Within 50 miles also contains extreme variations in elevation (12,740 feet).

The area within 2 miles of La Rioja is covered by grassland (31%), bare soil (22%), trees (22%), and shrubs (17%), within 10 miles by shrubs (66%) and trees (18%), and within 50 miles by shrubs (48%) and bare soil (18%).