Average Weather in Siwa Oasis Egypt
In Siwa Oasis, the summers are long, sweltering, arid, and clear and the winters are cool, dry, and mostly clear. Over the course of the year, the temperature typically varies from 44°F to 100°F and is rarely below 39°F or above 106°F.
Based on the beach/pool score, the best times of year to visit Siwa Oasis for hot-weather activities are from mid May to late July and from mid August to mid October.
The hot season lasts for 4.1 months, from May 20 to September 24, with an average daily high temperature above 93°F. The hottest day of the year is July 31, with an average high of 100°F and low of 73°F.
The cool season lasts for 3.2 months, from November 28 to March 3, with an average daily high temperature below 72°F. The coldest day of the year is January 29, with an average low of 44°F and high of 65°F.
Average High and Low Temperature
The figure below shows you a compact characterization of the entire year of hourly average temperatures. The horizontal axis is the day of the year, the vertical axis is the hour of the day, and the color is the average temperature for that hour and day.
Average Hourly Temperature
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
Desert Hot Springs, California, United States (7,425 miles away) and Tucson, Arizona, United States (7,329 miles) are the far-away foreign places with temperatures most similar to Siwa Oasis (view comparison).
In Siwa Oasis, the average percentage of the sky covered by clouds experiences significant seasonal variation over the course of the year.
The clearer part of the year in Siwa Oasis begins around May 29 and lasts for 4.6 months, ending around October 18. On June 27, the clearest day of the year, the sky is clear, mostly clear, or partly cloudy 100% of the time, and overcast or mostly cloudy 0% of the time.
The cloudier part of the year begins around October 18 and lasts for 7.4 months, ending around May 29. On December 1, the cloudiest day of the year, the sky is overcast or mostly cloudy 27% of the time, and clear, mostly clear, or partly cloudy 73% of the time.
Cloud Cover Categories
0% clear 20% mostly clear 40% partly cloudy 60% mostly cloudy 80% overcast 100%
Siwa Oasis does not experience significant seasonal variation in the frequency of wet days (i.e., those with greater than 0.04 inches of liquid or liquid-equivalent precipitation). The frequency ranges from -0% to 4%, with an average value of 1%.
Among wet days, we distinguish between those that experience rain alone, snow alone, or a mixture of the two. Based on this categorization, the most common form of precipitation throughout the year is rain alone, with a peak probability of 4% on December 30.
Daily Chance of Precipitation
The sliding 31-day quantity of rainfall in Siwa Oasis does not vary significantly over the course of the year, staying within 0.1 inches of 0.1 inches throughout.
Average Monthly Rainfall
The length of the day in Siwa Oasis varies significantly over the course of the year. In 2019, the shortest day is December 22, with 10 hours, 17 minutes of daylight; the longest day is June 21, with 14 hours, 1 minute of daylight.
Hours of Daylight and Twilight
The earliest sunrise is at 5:18 AM on June 11, and the latest sunrise is 1 hour, 55 minutes later at 7:13 AM on January 12. The earliest sunset is at 5:19 PM on December 2, and the latest sunset is 2 hours, 2 minutes later at 7:21 PM on July 1.
Daylight saving time (DST) is not observed in Siwa Oasis during 2019.
Sunrise & Sunset with Twilight
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 perceived humidity level in Siwa Oasis, as measured by the percentage of time in which the humidity comfort level is muggy, oppressive, or miserable, does not vary significantly over the course of the year, staying within 2% of 2% throughout.
Humidity Comfort Levels
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 Siwa Oasis experiences mild seasonal variation over the course of the year.
The windier part of the year lasts for 7.3 months, from January 14 to August 25, with average wind speeds of more than 8.4 miles per hour. The windiest day of the year is April 14, with an average hourly wind speed of 9.5 miles per hour.
The calmer time of year lasts for 4.7 months, from August 25 to January 14. The calmest day of the year is October 21, with an average hourly wind speed of 7.3 miles per hour.
Average Wind Speed
The predominant average hourly wind direction in Siwa Oasis varies throughout the year.
The wind is most often from the north for 3.9 weeks, from March 14 to April 10 and for 7.0 months, from April 30 to November 30, with a peak percentage of 74% on July 9. The wind is most often from the east for 2.9 weeks, from April 10 to April 30, with a peak percentage of 36% on April 29. The wind is most often from the west for 3.5 months, from November 30 to March 14, with a peak percentage of 42% on January 1.
Best Time of Year to Visit
To characterize how pleasant the weather is in Siwa Oasis 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 Siwa Oasis for general outdoor tourist activities are from mid March to late April and from early October to late November, with a peak score in the last week of October.
The beach/pool score favors clear, rainless days with perceived temperatures between 75°F and 90°F. Based on this score, the best times of year to visit Siwa Oasis for hot-weather activities are from mid May to late July and from mid August to mid October, with a peak score in the third week of September.
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).
Temperatures in Siwa Oasis 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
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.
Growing Degree Days
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 3.7 months, from May 5 to August 27, with an average daily incident shortwave energy per square meter above 7.5 kWh. The brightest day of the year is June 25, with an average of 8.5 kWh.
The darker period of the year lasts for 3.0 months, from November 7 to February 6, with an average daily incident shortwave energy per square meter below 4.6 kWh. The darkest day of the year is December 18, with an average of 3.6 kWh.
Average Daily Incident Shortwave Solar Energy
For the purposes of this report, the geographical coordinates of Siwa Oasis are 29.203 deg latitude, 25.520 deg longitude, and -43 ft elevation.
The topography within 2 miles of Siwa Oasis is essentially flat, with a maximum elevation change of 82 feet and an average elevation above sea level of -43 feet. Within 10 miles is essentially flat (515 feet). Within 50 miles contains significant variations in elevation (899 feet).
The area within 2 miles of Siwa Oasis is covered by cropland (64%), bare soil (25%), and water (11%), within 10 miles by bare soil (74%) and herbaceous vegetation (14%), and within 50 miles by bare soil (97%).
This report illustrates the typical weather in Siwa Oasis, based on a statistical analysis of historical hourly weather reports and model reconstructions from January 1, 1980 to December 31, 2016.
Siwa Oasis is further than 200 kilometers from the nearest reliable weather station, so the weather-related data on this page were taken entirely from NASA's MERRA-2 satellite-era reanalysis . 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.
The temperature and dew point estimates are corrected for the difference between the reference elevation of the MERRA-2 grid cell and the elevation of Siwa Oasis, according to the International Standard Atmosphere .
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.
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.