Daily high temperatures are around 88°F, rarely falling below 84°F or exceeding 93°F.
Daily low temperatures are around 75°F, rarely falling below 72°F or exceeding 78°F.
For reference, on March 24, the hottest day of the year, temperatures in Esparza typically range from 76°F to 95°F, while on October 2, the coldest day of the year, they range from 74°F to 88°F.
Average High and Low Temperature in September
The daily average high (red line) and low (blue line) temperature, with 25th to 75th and 10th to 90th percentile bands. The thin dotted lines are the corresponding average perceived temperatures.
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.
Average Hourly Temperature in September
The average hourly temperature, color coded into bands: frigid < 15°F < freezing < 32°F < very cold < 45°F < cold < 55°F < cool < 65°F < comfortable < 75°F < warm < 85°F < hot < 95°F < sweltering. The shaded overlays indicate night and civil twilight.
The month of September in Esparza experiences essentially constant cloud cover, with the percentage of time that the sky is overcast or mostly cloudy remaining about 92% throughout the month. The highest chance of overcast or mostly cloudy conditions is 92% on September 29.
The clearest day of the month is September 14, with clear, mostly clear, or partly cloudy conditions 9% of the time.
For reference, on June 5, the cloudiest day of the year, the chance of overcast or mostly cloudy conditions is 94%, while on January 1, the clearest day of the year, the chance of clear, mostly clear, or partly cloudy skies is 67%.
Cloud Cover Categories in September
The percentage of time spent in each cloud cover band, categorized by the percentage of the sky covered by clouds: clear < 20% < mostly clear < 40% < partly cloudy < 60% < mostly cloudy < 80% < overcast.
A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. In Esparza, the chance of a wet day over the course of September is rapidly increasing, starting the month at 42% and ending it at 48%.
For reference, the year's highest daily chance of a wet day is 49% on October 7, and its lowest chance is 3% on February 9.
Probability of Precipitation in September
The percentage of days in which various types of precipitation are observed, excluding trace quantities: rain alone, snow alone, and mixed (both rain and snow fell in the same day).
To 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 in Esparza is rapidly increasing, starting the month at 5.7 inches, when it rarely exceeds 10.7 inches or falls below 1.7 inches, and ending the month at 6.7 inches, when it rarely exceeds 13.4 inches or falls below 2.3 inches.
The highest average 31-day accumulation is 6.7 inches on September 29.
Average Monthly Rainfall in September
The average rainfall (solid line) accumulated over the course of a sliding 31-day period centered on the day in question, with 25th to 75th and 10th to 90th percentile bands. The thin dotted line is the corresponding average liquid-equivalent snowfall.
Over the course of September in Esparza, the length of the day is gradually decreasing. From the start to the end of the month, the length of the day decreases by 16 minutes, implying an average daily decrease of 33 seconds, and weekly decrease of 3 minutes, 49 seconds.
The shortest day of the month is September 30, with 12 hours, 2 minutes of daylight and the longest day is September 1, with 12 hours, 18 minutes of daylight.
Hours of Daylight and Twilight in September
The number of hours during which the Sun is visible (black line). From bottom (most yellow) to top (most gray), the color bands indicate: full daylight, twilight (civil, nautical, and astronomical), and full night.
The latest sunrise of the month in Esparza is 5:29 AM on September 1 and the earliest sunrise is 2 minutes, 7 seconds earlier at 5:27 AM on September 30.
The latest sunset is 5:47 PM on September 1 and the earliest sunset is 18 minutes earlier at 5:29 PM on September 30.
Daylight saving time is not observed in Esparza during 2018.
For reference, on June 21, the longest day of the year, the Sun rises at 5:19 AM and sets 12 hours, 43 minutes later, at 6:01 PM, while on December 21, the shortest day of the year, it rises at 5:50 AM and sets 11 hours, 33 minutes later, at 5:23 PM.
Sunrise & Sunset with Twilight in September
The solar day over the course of September. From bottom to top, the black lines are the previous solar midnight, sunrise, solar noon, sunset, and the next solar midnight. The day, twilights (civil, nautical, and astronomical), and night are indicated by the color bands from yellow to gray.
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 chance that a given day will be muggy in Esparza is essentially constant during September, remaining within 1% of 97% throughout.
The highest chance of a muggy day during September is 98% on September 28.
For reference, on June 6, the muggiest day of the year, there are muggy conditions 98% of the time, while on February 2, the least muggy day of the year, there are muggy conditions 21% of the time.
Humidity Comfort Levels in September
The percentage of time spent at various humidity comfort levels, categorized by dew point: 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 Esparza is essentially constant during September, remaining within 0.1 miles per hour of 3.9 miles per hour throughout.
For reference, on February 5, the windiest day of the year, the daily average wind speed is 6.6 miles per hour, while on June 16, the calmest day of the year, the daily average wind speed is 3.6 miles per hour.
Average Wind Speed in September
The average of mean hourly wind speeds (dark gray line), with 25th to 75th and 10th to 90th percentile bands.
The hourly average wind direction in Esparza throughout September is predominantly from the west, with a peak proportion of 46% on September 30.
Wind Direction in September
The percentage of hours in which the mean wind direction is from each of the four cardinal wind directions (north, east, south, and west), excluding hours in which the mean wind speed is less than 1 mph. The lightly tinted areas at the boundaries are the percentage of hours spent in the implied intermediate directions (northeast, southeast, southwest, and northwest).
Esparza 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 Esparza is essentially constant during September, remaining around 83°F throughout.
Average Water Temperature in September
The daily average water temperature (purple line), with 25th to 75th and 10th to 90th percentile bands.
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 Esparza 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 in September
The percentage of time spent in various temperature bands: frigid < 15°F < freezing < 32°F < very cold < 45°F < cold < 55°F < cool < 65°F < comfortable < 75°F < warm < 85°F < hot < 95°F < sweltering. The black line is the percentage chance that a given day is 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 Esparza are rapidly increasing during September, increasing by 850°F, from 7,567°F to 8,417°F, over the course of the month.
Growing Degree Days in September
The average growing degree days accumulated over the course of September, with 25th to 75th and 10th to 90th percentile bands.
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 in Esparza is essentially constant during September, remaining within 0.1 kWh of 4.0 kWh throughout.
Average Daily Incident Shortwave Solar Energy in September
The average daily shortwave solar energy reaching the ground per square meter (orange line), with 25th to 75th and 10th to 90th percentile bands.
For the purposes of this report, the geographical coordinates of Esparza are 9.994 deg latitude, -84.665 deg longitude, and 627 ft elevation.
The topography within 2 miles of Esparza contains very significant variations in elevation, with a maximum elevation change of 974 feet and an average elevation above sea level of 608 feet. Within 10 miles contains very significant variations in elevation (4,780 feet). Within 50 miles also contains extreme variations in elevation (9,564 feet).
The area within 2 miles of Esparza is covered by grassland (56%) and trees (31%), within 10 miles by grassland (35%) and trees (32%), and within 50 miles by trees (34%) and water (30%).
This report illustrates the typical weather in Esparza year round, 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, Juan Santamaría International Airport, in our network suitable to be used as a proxy for the historical temperature and dew point records of Esparza.
At a distance of 50 kilometers from Esparza, 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.
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.
The 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.