Climate and Average Weather Year Round in Siesta Key Florida, United StatesIn Siesta Key, the summers are long, hot, oppressive, wet, and mostly cloudy and the winters are short, cool, windy, and partly cloudy. Over the course of the year, the temperature typically varies from 53°F to 89°F and is rarely below 40°F or above 92°F. Based on the tourism score, the best times of year to visit Siesta Key for warm-weather activities are from late February to early May and from late October to early December. Average Temperature in Siesta KeyThe hot season lasts for 4.5 months, from May 22 to October 6, with an average daily high temperature above 85°F. The hottest month of the year in Siesta Key is August, with an average high of 89°F and low of 75°F. The cool season lasts for 2.8 months, from December 9 to March 3, with an average daily high temperature below 74°F. The coldest month of the year in Siesta Key is January, with an average low of 54°F and high of 71°F.
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. Pāsighāt, Arunachal Pradesh, India (8,620 miles away) and Nantou, Taiwan (8,586 miles) are the far-away foreign places with temperatures most similar to Siesta Key (view comparison). CloudsIn Siesta Key, 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 Siesta Key begins around October 4 and lasts for 8.0 months, ending around June 4. The clearest month of the year in Siesta Key is February, during which on average the sky is clear, mostly clear, or partly cloudy 64% of the time. The cloudier part of the year begins around June 4 and lasts for 4.0 months, ending around October 4. The cloudiest month of the year in Siesta Key is July, during which on average the sky is overcast or mostly cloudy 66% of the time.
PrecipitationA wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. The chance of wet days in Siesta Key varies very significantly throughout the year. The wetter season lasts 3.8 months, from June 4 to September 28, with a greater than 41% chance of a given day being a wet day. The month with the most wet days in Siesta Key is August, with an average of 20.3 days with at least 0.04 inches of precipitation. The drier season lasts 8.2 months, from September 28 to June 4. The month with the fewest wet days in Siesta Key is November, with an average of 4.4 days with at least 0.04 inches of precipitation. Among wet days, we distinguish between those that experience rain alone, snow alone, or a mixture of the two. The month with the most days of rain alone in Siesta Key is August, with an average of 20.3 days. Based on this categorization, the most common form of precipitation throughout the year is rain alone, with a peak probability of 69% on August 2.
RainfallTo show variation within the months and not just the monthly totals, we show the rainfall accumulated over a sliding 31-day period centered around each day of the year. Siesta Key experiences significant seasonal variation in monthly rainfall. Rain falls throughout the year in Siesta Key. The month with the most rain in Siesta Key is August, with an average rainfall of 5.4 inches. The month with the least rain in Siesta Key is November, with an average rainfall of 1.5 inches.
SunThe length of the day in Siesta Key varies over the course of the year. In 2024, the shortest day is December 21, with 10 hours, 25 minutes of daylight; the longest day is June 20, with 13 hours, 52 minutes of daylight.
The earliest sunrise is at 6:34 AM on June 9, and the latest sunrise is 1 hour, 10 minutes later at 7:44 AM on March 10. The earliest sunset is at 5:35 PM on November 30, and the latest sunset is 2 hours, 53 minutes later at 8:29 PM on July 1. Daylight saving time (DST) is observed in Siesta Key during 2024, starting in the spring on March 10, lasting 7.8 months, and ending in the fall on November 3. 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 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. 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. Siesta Key experiences extreme seasonal variation in the perceived humidity. The muggier period of the year lasts for 7.4 months, from April 3 to November 15, during which time the comfort level is muggy, oppressive, or miserable at least 37% of the time. The month with the most muggy days in Siesta Key is August, with 30.9 days that are muggy or worse. The month with the fewest muggy days in Siesta Key is January, with 5.4 days that are muggy or worse.
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 Siesta Key experiences significant seasonal variation over the course of the year. The windier part of the year lasts for 7.7 months, from September 18 to May 9, with average wind speeds of more than 8.7 miles per hour. The windiest month of the year in Siesta Key is November, with an average hourly wind speed of 10.8 miles per hour. The calmer time of year lasts for 4.3 months, from May 9 to September 18. The calmest month of the year in Siesta Key is July, with an average hourly wind speed of 6.5 miles per hour.
The predominant average hourly wind direction in Siesta Key varies throughout the year. The wind is most often from the east for 3.0 months, from March 13 to June 14; for 3.3 months, from August 1 to November 11; and for 1.0 weeks, from November 22 to November 29, with a peak percentage of 51% on September 23. The wind is most often from the west for 1.6 months, from June 14 to August 1, with a peak percentage of 33% on July 5. The wind is most often from the north for 1.6 weeks, from November 11 to November 22 and for 3.5 months, from November 29 to March 13, with a peak percentage of 40% on November 20. Water TemperatureSiesta Key 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 water temperature experiences some seasonal variation over the course of the year. The time of year with warmer water lasts for 4.0 months, from June 8 to October 9, with an average temperature above 82°F. The month of the year in Siesta Key with the warmest water is August, with an average temperature of 86°F. The time of year with cooler water lasts for 3.2 months, from December 20 to March 26, with an average temperature below 70°F. The month of the year in Siesta Key with the coolest water is February, with an average temperature of 66°F.
Best Time of Year to VisitTo characterize how pleasant the weather is in Siesta Key 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 Siesta Key for general outdoor tourist activities are from late February to early May and from late October to early December, with a peak score in the second week of April. Tourism Score in Siesta KeyThe 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 Siesta Key for hot-weather activities are from late April to early June and for the entire month of October, with a peak score in the third week of May. Beach/Pool Score in Siesta KeyMethodologyFor 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. 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). While it does not do so every year, freezing temperatures are seen in Siesta Key over some winters. The day least likely to be in the growing season is January 16, with a 78% chance. 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. Based on growing degree days alone, the first spring blooms in Siesta Key should appear around January 8, only rarely appearing before January 6 or after January 13. 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 experiences significant seasonal variation over the course of the year. The brighter period of the year lasts for 1.8 months, from April 1 to May 28, with an average daily incident shortwave energy per square meter above 6.2 kWh. The brightest month of the year in Siesta Key is May, with an average of 6.6 kWh. The darker period of the year lasts for 2.6 months, from November 11 to January 29, with an average daily incident shortwave energy per square meter below 4.2 kWh. The darkest month of the year in Siesta Key is December, with an average of 3.6 kWh.
TopographyFor the purposes of this report, the geographical coordinates of Siesta Key are 27.268 deg latitude, -82.545 deg longitude, and 3 ft elevation. The topography within 2 miles of Siesta Key is essentially flat, with a maximum elevation change of 23 feet and an average elevation above sea level of 4 feet. Within 10 miles is also essentially flat (36 feet). Within 50 miles is essentially flat (161 feet). The area within 2 miles of Siesta Key is covered by artificial surfaces (48%) and water (41%), within 10 miles by water (56%) and artificial surfaces (33%), and within 50 miles by water (58%) and cropland (15%). Data SourcesThis report illustrates the typical weather in Siesta Key, 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 Siesta Key. For each station, the records are corrected for the elevation difference between that station and Siesta Key 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 Siesta Key is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Siesta Key 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 Siesta Key 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. |