September Weather at Beirut International Airport LebanonDaily high temperatures decrease by 3°F, from 86°F to 83°F, rarely falling below 80°F or exceeding 89°F. Daily low temperatures decrease by 4°F, from 77°F to 73°F, rarely falling below 68°F or exceeding 80°F. For reference, on August 10, the hottest day of the year, temperatures at Beirut International Airport typically range from 77°F to 87°F, while on January 24, the coldest day of the year, they range from 52°F to 62°F. The figure below shows you a compact characterization of the hourly average temperatures for the quarter of the year centered on September. 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. Xiamen, China (4,900 miles away) is the far-away foreign place with temperatures most similar to Beirut International Airport (view comparison). CloudsThe month of September at Beirut International Airport experiences increasing cloud cover, with the percentage of time that the sky is overcast or mostly cloudy increasing from 0% to 9%. The clearest day of the month is September 1, with clear, mostly clear, or partly cloudy conditions 100% of the time. For reference, on December 12, the cloudiest day of the year, the chance of overcast or mostly cloudy conditions is 39%, while on August 8, the clearest day of the year, the chance of clear, mostly clear, or partly cloudy skies is 100%. PrecipitationA wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. At Beirut International Airport, the chance of a wet day over the course of September is gradually increasing, starting the month at 0% and ending it at 4%. For reference, the year's highest daily chance of a wet day is 32% on January 19, and its lowest chance is -0% on August 15. RainfallTo 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 September at Beirut International Airport is gradually increasing, starting the month at 0.0 inches, when it rarely exceeds 0.1 inches or falls below -0.0 inches, and ending the month at 0.3 inches, when it rarely exceeds 0.8 inches. SunOver the course of September at Beirut International Airport, the length of the day is decreasing. From the start to the end of the month, the length of the day decreases by 1 hour, 0 minutes, implying an average daily decrease of 2 minutes, 4 seconds, and weekly decrease of 14 minutes, 28 seconds. The shortest day of the month is September 30, with 11 hours, 51 minutes of daylight and the longest day is September 1, with 12 hours, 51 minutes of daylight. The earliest sunrise of the month at Beirut International Airport is 6:12 AM on September 1 and the latest sunrise is 20 minutes later at 6:31 AM on September 30. The latest sunset is 7:03 PM on September 1 and the earliest sunset is 40 minutes earlier at 6:23 PM on September 30. Daylight saving time is observed at Beirut International Airport during 2024, but it neither starts nor ends during September, so the entire month is in daylight saving time. For reference, on June 20, the longest day of the year, the Sun rises at 5:27 AM and sets 14 hours, 24 minutes later, at 7:51 PM, while on December 21, the shortest day of the year, it rises at 6:39 AM and sets 9 hours, 54 minutes later, at 4:33 PM. The figure below presents a compact representation of the sun's elevation (the angle of the sun above the horizon) and azimuth (its compass bearing) for every hour of every day in the reporting period. The horizontal axis is the day of the year and the vertical axis is the hour of the day. For a given day and hour of that day, the background color indicates the azimuth of the sun at that moment. The black isolines are contours of constant solar elevation. MoonThe figure below presents a compact representation of key lunar data for September 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. 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.
HumidityWe 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 at Beirut International Airport is very rapidly decreasing during September, falling from 81% to 45% over the course of the month. For reference, on August 2, the muggiest day of the year, there are muggy conditions 91% of the time, while on December 14, the least muggy day of the year, there are muggy conditions 0% of the time. WindThis 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 at Beirut International Airport is essentially constant during September, remaining within 0.1 miles per hour of 6.5 miles per hour throughout. For reference, on February 7, the windiest day of the year, the daily average wind speed is 9.3 miles per hour, while on September 2, the calmest day of the year, the daily average wind speed is 6.4 miles per hour. The lowest daily average wind speed during September is 6.4 miles per hour on September 3. The hourly average wind direction at Beirut International Airport throughout September is predominantly from the west, with a peak proportion of 59% on September 1. Water TemperatureBeirut International Airport 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 at Beirut International Airport is gradually decreasing during September, falling by 2°F, from 83°F to 80°F, over the course of the month. Growing SeasonDefinitions 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 at Beirut International Airport 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. 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 at Beirut International Airport are rapidly increasing during September, increasing by 868°F, from 4,684°F to 5,551°F, over the course of the month. Solar EnergyThis 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 at Beirut International Airport is decreasing during September, falling by 1.4 kWh, from 7.1 kWh to 5.7 kWh, over the course of the month. TopographyFor the purposes of this report, the geographical coordinates of Beirut International Airport are 33.821 deg latitude, 35.488 deg longitude, and 13 ft elevation. The topography within 2 miles of Beirut International Airport contains significant variations in elevation, with a maximum elevation change of 748 feet and an average elevation above sea level of 64 feet. Within 10 miles contains significant variations in elevation (4,173 feet). Within 50 miles also contains extreme variations in elevation (10,177 feet). The area within 2 miles of Beirut International Airport is covered by artificial surfaces (32%), water (28%), sparse vegetation (16%), and cropland (11%), within 10 miles by water (49%) and trees (17%), and within 50 miles by water (51%) and cropland (15%). Data SourcesThis report illustrates the typical weather at Beirut International Airport, based on a statistical analysis of historical hourly weather reports and model reconstructions from January 1, 1980 to December 31, 2016. Temperature and Dew PointBeirut International Airport has a weather station that reported reliably enough during the analysis period that we have included it in our network. When available, historical temperature and dew point measurements are taken directly from this weather station. These records are obtained from NOAA's Integrated Surface Hourly data set, falling back on ICAO METAR records as required. In the case of missing or erroneous measurements from this station, we fall back on records from nearby stations, adjusted according to typical seasonal and diurnal intra-station differences. For a given day of the year and hour of the day, the fallback station is selected to minimize the prediction error over the years for which there are measurements for both stations. The stations on which we may fall back are Damascus International Airport, Haifa International Airport, Irbid, and King Hussein Air Base. Other DataAll 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 © OpenStreetMap contributors. DisclaimerThe 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. Please review our full terms contained on our Terms of Service page. |