September Weather at Indian Mountain Long Range Radar Site United StatesDaily high temperatures decrease by 17°F, from 55°F to 38°F, rarely falling below 29°F or exceeding 63°F. Daily low temperatures decrease by 13°F, from 40°F to 27°F, rarely falling below 16°F or exceeding 47°F. For reference, on June 28, the hottest day of the year, temperatures at Indian Mountain Long Range Radar Site typically range from 50°F to 69°F, while on January 19, the coldest day of the year, they range from -11°F to 3°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. Kogalym, Russia (3,249 miles away) is the far-away foreign place with temperatures most similar to Indian Mountain Long Range Radar Site (view comparison). CloudsThe month of September at Indian Mountain Long Range Radar Site experiences essentially constant cloud cover, with the percentage of time that the sky is overcast or mostly cloudy remaining about 64% throughout the month. The highest chance of overcast or mostly cloudy conditions is 66% on September 23. The clearest day of the month is September 1, with clear, mostly clear, or partly cloudy conditions 37% of the time. For reference, on December 12, the cloudiest day of the year, the chance of overcast or mostly cloudy conditions is 68%, while on May 15, the clearest day of the year, the chance of clear, mostly clear, or partly cloudy skies is 45%. PrecipitationA wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. At Indian Mountain Long Range Radar Site, the chance of a wet day over the course of September is decreasing, starting the month at 28% and ending it at 22%. For reference, the year's highest daily chance of a wet day is 33% on August 1, and its lowest chance is 7% on March 19. Over the course of September at Indian Mountain Long Range Radar Site, the chance of a day with only rain decreases from 27% to 12%, the chance of a day with mixed snow and rain increases from 0% to 4%, and the chance of a day with only snow increases from 0% to 6%. 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 Indian Mountain Long Range Radar Site is rapidly decreasing, starting the month at 1.9 inches, when it rarely exceeds 3.3 inches or falls below 0.8 inches, and ending the month at 0.8 inches, when it rarely exceeds 1.7 inches or falls below 0.2 inches. SnowfallAs with rainfall, we consider the snowfall accumulated over a sliding 31-day period centered around each day. The average sliding 31-day snowfall during September at Indian Mountain Long Range Radar Site is rapidly increasing, starting the month at 0.4 inches, when it rarely exceeds 1.4 inches, and ending the month at 4.0 inches, when it rarely exceeds 8.1 inches or falls below 0.6 inches. SunDue to its extreme latitude, Indian Mountain Long Range Radar Site experiences polar day (also known as the midnight Sun) during the summer. The precise start and end dates of polar day and night vary from year to year and depend on the precise location and elevation of the observer, and the local topography. Neither polar day nor polar night occur during the month of September. Over the course of September at Indian Mountain Long Range Radar Site, the length of the day is very rapidly decreasing. From the start to the end of the month, the length of the day decreases by 3 hours, 24 minutes, implying an average daily decrease of 7 minutes, 2 seconds, and weekly decrease of 49 minutes, 12 seconds. The shortest day of the month is September 30, with 11 hours, 17 minutes of daylight and the longest day is September 1, with 14 hours, 41 minutes of daylight. The earliest sunrise of the month at Indian Mountain Long Range Radar Site is 6:52 AM on September 1 and the latest sunrise is 1 hour, 32 minutes later at 8:24 AM on September 30. The latest sunset is 9:34 PM on September 1 and the earliest sunset is 1 hour, 52 minutes earlier at 7:42 PM on September 30. Daylight saving time is observed at Indian Mountain Long Range Radar Site during 2024, but it neither starts nor ends during September, so the entire month is in standard time. 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 Indian Mountain Long Range Radar Site is essentially constant during September, remaining around 0% throughout. For reference, on June 28, the muggiest day of the year, there are muggy conditions 0% of the time, while on January 1, 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 Indian Mountain Long Range Radar Site is gradually increasing during September, increasing from 7.2 miles per hour to 7.9 miles per hour over the course of the month. For reference, on January 9, the windiest day of the year, the daily average wind speed is 10.6 miles per hour, while on June 18, the calmest day of the year, the daily average wind speed is 6.9 miles per hour. The hourly average wind direction at Indian Mountain Long Range Radar Site throughout September is predominantly from the east, with a peak proportion of 47% on September 30. 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). The growing season at Indian Mountain Long Range Radar Site typically lasts for 3.3 months (101 days), from around May 21 to around August 30, rarely starting before May 5 or after June 6, and rarely ending before August 11 or after September 19. The month of September at Indian Mountain Long Range Radar Site is more likely than not fully outside of the growing season, with the chance that a given day is in the growing season rapidly decreasing from 46% to 3% over the course of the month. 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 Indian Mountain Long Range Radar Site are essentially constant during September, remaining within 11°F of 738°F throughout. 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 Indian Mountain Long Range Radar Site is decreasing during September, falling by 1.4 kWh, from 2.9 kWh to 1.5 kWh, over the course of the month. TopographyFor the purposes of this report, the geographical coordinates of Indian Mountain Long Range Radar Site are 65.994 deg latitude, -153.697 deg longitude, and 1,017 ft elevation. The topography within 2 miles of Indian Mountain Long Range Radar Site contains very significant variations in elevation, with a maximum elevation change of 1,634 feet and an average elevation above sea level of 1,322 feet. Within 10 miles contains very significant variations in elevation (3,835 feet). Within 50 miles also contains extreme variations in elevation (4,760 feet). The area within 2 miles of Indian Mountain Long Range Radar Site is covered by trees (72%) and shrubs (28%), within 10 miles by trees (47%) and shrubs (40%), and within 50 miles by shrubs (54%) and trees (40%). Data SourcesThis report illustrates the typical weather at Indian Mountain Long Range Radar Site, based on a statistical analysis of historical hourly weather reports and model reconstructions from January 1, 1980 to December 31, 2016. Temperature and Dew PointIndian Mountain Long Range Radar Site 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 Ralph M Calhoun Memorial Airport, Ruby Airport, Bettles Airport, Huslia Airport, and Huslia. 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. |