Average Weather in As Sulayyil Saudi Arabia
In As Sulayyil, the summers are long, sweltering, arid, and partly cloudy and the winters are short, comfortable, dry, windy, and mostly clear. Over the course of the year, the temperature typically varies from 51°F to 110°F and is rarely below 44°F or above 113°F.
Based on the beach/pool score, the best times of year to visit As Sulayyil for hot-weather activities are from mid March to late April and from late September to early November.
The hot season lasts for 4.3 months, from May 11 to September 21, with an average daily high temperature above 103°F. The hottest day of the year is July 23, with an average high of 110°F and low of 85°F.
The cool season lasts for 2.7 months, from November 27 to February 19, with an average daily high temperature below 81°F. The coldest day of the year is January 9, with an average low of 51°F and high of 74°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
In As Sulayyil, 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 As Sulayyil begins around August 24 and lasts for 9.8 months, ending around June 18. On September 25, the clearest day of the year, the sky is clear, mostly clear, or partly cloudy 84% of the time, and overcast or mostly cloudy 16% of the time.
The cloudier part of the year begins around June 18 and lasts for 2.2 months, ending around August 24. On July 24, the cloudiest day of the year, the sky is overcast or mostly cloudy 50% of the time, and clear, mostly clear, or partly cloudy 50% of the time.
Cloud Cover Categories
0% clear 20% mostly clear 40% partly cloudy 60% mostly cloudy 80% overcast 100%
As Sulayyil 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 3%, 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 3% on April 21.
Daily Chance of Precipitation
The sliding 31-day quantity of rainfall in As Sulayyil 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 As Sulayyil varies over the course of the year. In 2018, the shortest day is December 22, with 10 hours, 54 minutes of daylight; the longest day is June 21, with 13 hours, 22 minutes of daylight.
Hours of Daylight and Twilight
The earliest sunrise is at 5:16 AM on June 7, and the latest sunrise is 1 hour, 20 minutes later at 6:36 AM on January 17. The earliest sunset is at 5:15 PM on November 26, and the latest sunset is 1 hour, 26 minutes later at 6:42 PM on July 4.
Daylight saving time (DST) is not observed in As Sulayyil during 2018.
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 As Sulayyil, 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 3% of 3% 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 As Sulayyil experiences mild seasonal variation over the course of the year.
The windier part of the year lasts for 3.6 months, from January 7 to April 27, with average wind speeds of more than 9.3 miles per hour. The windiest day of the year is March 18, with an average hourly wind speed of 10.3 miles per hour.
The calmer time of year lasts for 8.4 months, from April 27 to January 7. The calmest day of the year is August 23, with an average hourly wind speed of 8.2 miles per hour.
Average Wind Speed
The predominant average hourly wind direction in As Sulayyil varies throughout the year.
The wind is most often from the north for 1.7 weeks, from July 5 to July 17, with a peak percentage of 39% on July 11. The wind is most often from the east for 12 months, from July 17 to July 5, with a peak percentage of 64% on January 1.
Best Time of Year to Visit
To characterize how pleasant the weather is in As Sulayyil 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 time of year to visit As Sulayyil for general outdoor tourist activities is from early November to mid March, with a peak score in the last week of November.
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 As Sulayyil for hot-weather activities are from mid March to late April and from late September to early November, with a peak score in the third week of October.
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 As Sulayyil 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
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 some seasonal variation over the course of the year.
The brighter period of the year lasts for 4.4 months, from April 26 to September 8, with an average daily incident shortwave energy per square meter above 7.3 kWh. The brightest day of the year is June 13, with an average of 7.9 kWh.
The darker period of the year lasts for 2.6 months, from November 14 to February 2, with an average daily incident shortwave energy per square meter below 5.5 kWh. The darkest day of the year is December 28, with an average of 4.9 kWh.
Average Daily Incident Shortwave Solar Energy
For the purposes of this report, the geographical coordinates of As Sulayyil are 20.461 deg latitude, 45.578 deg longitude, and 1,988 ft elevation.
The topography within 2 miles of As Sulayyil contains only modest variations in elevation, with a maximum elevation change of 128 feet and an average elevation above sea level of 1,992 feet. Within 10 miles also contains only modest variations in elevation (456 feet). Within 50 miles contains only modest variations in elevation (1,430 feet).
The area within 2 miles of As Sulayyil is covered by bare soil (90%), within 10 miles by bare soil (95%), and within 50 miles by bare soil (97%).
This report illustrates the typical weather in As Sulayyil, 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, Wadi al-Dawasir Domestic Airport, in our network suitable to be used as a proxy for the historical temperature and dew point records of As Sulayyil.
At a distance of 40 kilometers from As Sulayyil, 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 As Sulayyil 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 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.