Summer Weather in Sebastopol United StatesDaily high temperatures increase by 4°F, from 76°F to 80°F, rarely falling below 66°F or exceeding 92°F. The highest daily average high temperature is 81°F on August 23. Daily low temperatures are around 51°F, rarely falling below 45°F or exceeding 56°F. The highest daily average low temperature is 52°F on July 25. For reference, on August 22, the hottest day of the year, temperatures in Sebastopol typically range from 52°F to 81°F, while on December 31, the coldest day of the year, they range from 38°F to 56°F. The figure below shows you a compact characterization of the hourly average summer temperatures. 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. Melipilla, Chile (5,986 miles away) is the far-away foreign place with temperatures most similar to Sebastopol (view comparison). CloudsThe summer in Sebastopol experiences rapidly decreasing cloud cover, with the percentage of time that the sky is overcast or mostly cloudy decreasing from 26% to 11%. The lowest chance of overcast or mostly cloudy conditions is 8% on July 26. The clearest day of the summer is July 26, with clear, mostly clear, or partly cloudy conditions 92% of the time. For reference, on January 10, the cloudiest day of the year, the chance of overcast or mostly cloudy conditions is 58%, while on July 26, the clearest day of the year, the chance of clear, mostly clear, or partly cloudy skies is 92%. PrecipitationA wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. In Sebastopol, the chance of a wet day over the course of the summer is gradually decreasing, starting the season at 5% and ending it at 2%. For reference, the year's highest daily chance of a wet day is 35% on February 27, and its lowest chance is 0% on July 25. RainfallTo show variation within the season and not just the monthly totals, we show the rainfall accumulated over a sliding 31-day period centered around each day. The average sliding 31-day rainfall during the summer in Sebastopol is gradually decreasing, starting the season at 0.5 inches, when it rarely exceeds 1.8 inches, and ending the season at 0.1 inches, when it rarely exceeds 0.3 inches. The lowest average 31-day accumulation is 0.0 inches on July 29. SunOver the course of the summer in Sebastopol, the length of the day is rapidly decreasing. From the start to the end of the season, the length of the day decreases by 1 hour, 40 minutes, implying an average daily decrease of 1 minute, 6 seconds, and weekly decrease of 7 minutes, 40 seconds. The shortest day of the summer is August 31, with 13 hours, 1 minute of daylight and the longest day is June 20, with 14 hours, 51 minutes of daylight. The earliest sunrise of the summer in Sebastopol is 5:46 AM on June 13 and the latest sunrise is 54 minutes later at 6:40 AM on August 31. The latest sunset is 8:39 PM on June 27 and the earliest sunset is 58 minutes earlier at 7:41 PM on August 31. Daylight saving time is observed in Sebastopol during 2024, but it neither starts nor ends during the summer, so the entire season is in standard time. For reference, on June 20, the longest day of the year, the Sun rises at 5:47 AM and sets 14 hours, 51 minutes later, at 8:38 PM, while on December 21, the shortest day of the year, it rises at 7:25 AM and sets 9 hours, 29 minutes later, at 4:54 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 the summer of 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 in Sebastopol is essentially constant during the summer, remaining around 0% throughout. For reference, on July 2, 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 in Sebastopol is decreasing during the summer, decreasing from 8.8 miles per hour to 7.2 miles per hour over the course of the season. For reference, on June 5, the windiest day of the year, the daily average wind speed is 8.8 miles per hour, while on October 20, the calmest day of the year, the daily average wind speed is 6.8 miles per hour. The highest daily average wind speed during the summer is 8.8 miles per hour on June 5. The hourly average wind direction in Sebastopol throughout the summer is predominantly from the west, with a peak proportion of 82% on July 29. Water TemperatureSebastopol 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 in Sebastopol is increasing during the summer, rising by 4°F, from 52°F to 56°F, over the course of the season. 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 in Sebastopol typically lasts for 9.9 months (300 days), from around February 6 to around December 2, rarely starting after March 10, or ending before November 12. The summer in Sebastopol is reliably fully within 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. The average accumulated growing degree days in Sebastopol are very rapidly increasing during the summer, increasing by 1,186°F, from 778°F to 1,964°F, over the course of the season. 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 in Sebastopol is decreasing during the summer, falling by 1.1 kWh, from 7.9 kWh to 6.8 kWh, over the course of the season. The highest average daily incident shortwave solar energy during the summer is 8.4 kWh on June 29. TopographyFor the purposes of this report, the geographical coordinates of Sebastopol are 38.402 deg latitude, -122.824 deg longitude, and 82 ft elevation. The topography within 2 miles of Sebastopol contains only modest variations in elevation, with a maximum elevation change of 325 feet and an average elevation above sea level of 136 feet. Within 10 miles contains only modest variations in elevation (1,398 feet). Within 50 miles contains very significant variations in elevation (4,698 feet). The area within 2 miles of Sebastopol is covered by cropland (78%) and artificial surfaces (14%), within 10 miles by grassland (39%) and cropland (27%), and within 50 miles by water (36%) and shrubs (21%). Data SourcesThis report illustrates the typical weather in Sebastopol, based on a statistical analysis of historical hourly weather reports and model reconstructions from January 1, 1980 to December 31, 2016. Temperature and Dew PointThere are 2 weather stations near enough to contribute to our estimation of the temperature and dew point in Sebastopol. For each station, the records are corrected for the elevation difference between that station and Sebastopol according to the International Standard Atmosphere , and by the relative change present in the MERRA-2 satellite-era reanalysis between the two locations. The estimated value at Sebastopol is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Sebastopol and a given station. The stations contributing to this reconstruction are:
To get a sense of how much these sources agree with each other, you can view a comparison of Sebastopol and the stations that contribute to our estimates of its temperature history and climate. Please note that each source's contribution is adjusted for elevation and the relative change present in the MERRA-2 data. 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. |