Average Weather in Twain Harte California, United States
In Twain Harte, the summers are warm, arid, and mostly clear and the winters are long, chilly, wet, and partly cloudy. Over the course of the year, the temperature typically varies from 31°F to 85°F and is rarely below 22°F or above 91°F.
The warm season lasts for 3.3 months, from June 11 to September 20, with an average daily high temperature above 77°F. The hottest day of the year is July 28, with an average high of 85°F and low of 56°F.
The cold season lasts for 3.8 months, from November 19 to March 12, with an average daily high temperature below 55°F. The coldest day of the year is December 23, with an average low of 31°F and high of 48°F.
Average High and Low Temperature
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.
Average Hourly Temperature
In Twain Harte, 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 Twain Harte begins around May 20 and lasts for 5.2 months, ending around October 26. On August 8, the clearest day of the year, the sky is clear, mostly clear, or partly cloudy 90% of the time, and overcast or mostly cloudy 10% of the time.
The cloudier part of the year begins around October 26 and lasts for 6.8 months, ending around May 20. On February 21, the cloudiest day of the year, the sky is overcast or mostly cloudy 56% of the time, and clear, mostly clear, or partly cloudy 44% of the time.
A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. The chance of wet days in Twain Harte varies significantly throughout the year.
The wetter season lasts 5.7 months, from November 2 to April 22, with a greater than 16% chance of a given day being a wet day. The chance of a wet day peaks at 32% on February 21.
The drier season lasts 6.3 months, from April 22 to November 2. The smallest chance of a wet day is 0% on August 5.
Among wet days, we distinguish between those that experience rain alone, snow alone, or a mixture of the two. Based on this categorization, the most common form of precipitation throughout the year is rain alone, with a peak probability of 27% on February 21.
Daily Chance of Precipitation
To 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. Twain Harte experiences extreme seasonal variation in monthly rainfall.
The rainy period of the year lasts for 8.3 months, from September 24 to June 2, with a sliding 31-day rainfall of at least 0.5 inches. The most rain falls during the 31 days centered around February 16, with an average total accumulation of 4.3 inches.
The rainless period of the year lasts for 3.7 months, from June 2 to September 24. The least rain falls around August 11, with an average total accumulation of 0.0 inches.
Average Monthly Rainfall
The sliding 31-day liquid-equivalent quantity of snowfall in Twain Harte does not vary significantly over the course of the year, staying within 0.1 inches of 0.1 inches throughout.
Average Liquid-Equivalent Monthly Snowfall
The length of the day in Twain Harte varies significantly over the course of the year. In 2017, the shortest day is December 21, with 9 hours, 31 minutes of daylight; the longest day is June 21, with 14 hours, 49 minutes of daylight.
Hours of Daylight and Twilight
The earliest sunrise is at 5:37 AM on June 13, and the latest sunrise is 1 hour, 53 minutes later at 7:30 AM on November 4. The earliest sunset is at 4:41 PM on December 6, and the latest sunset is 3 hours, 47 minutes later at 8:27 PM on June 27.
Daylight saving time (DST) is observed in Twain Harte during 2017, starting in the spring on March 12, lasting 7.8 months, and ending in the fall on November 5.
Sunrise & Sunset with Twilight and Daylight Saving Time
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 perceived humidity level in Twain Harte, as measured by the percentage of time in which the humidity comfort level is muggy, oppressive, or miserable, does not vary significantly over the course of the year, remaining a virtually constant 0% throughout.
Humidity Comfort Levels
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 Twain Harte does not vary significantly over the course of the year, remaining within 0.2 miles per hour of 2.9 miles per hour throughout.
Average Wind Speed
The predominant average hourly wind direction in Twain Harte varies throughout the year.
The wind is most often from the south for 1.3 months, from February 18 to March 28, with a peak percentage of 38% on February 20. The wind is most often from the west for 5.9 months, from March 28 to September 25, with a peak percentage of 49% on June 10. The wind is most often from the east for 4.8 months, from September 25 to February 18, with a peak percentage of 48% on January 1.
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 experiences extreme seasonal variation over the course of the year.
The brighter period of the year lasts for 3.5 months, from May 8 to August 23, with an average daily incident shortwave energy per square meter above 7.4 kWh. The brightest day of the year is June 26, with an average of 8.6 kWh.
The darker period of the year lasts for 3.5 months, from November 3 to February 17, with an average daily incident shortwave energy per square meter below 3.6 kWh. The darkest day of the year is December 22, with an average of 2.3 kWh.
Average Daily Incident Shortwave Solar Energy
For the purposes of this report, the geographical coordinates of Twain Harte are 38.040 deg latitude, -120.233 deg longitude, and 3,727 ft elevation.
The topography within 2 miles of Twain Harte contains very significant variations in elevation, with a maximum elevation change of 1,785 feet and an average elevation above sea level of 3,811 feet. Within 10 miles contains very significant variations in elevation (5,118 feet). Within 50 miles also contains extreme variations in elevation (12,208 feet).
The area within 2 miles of Twain Harte is covered by trees (51%) and shrubs (49%), within 10 miles by trees (48%) and shrubs (47%), and within 50 miles by shrubs (31%) and trees (31%).
This report illustrates the typical weather in Twain Harte, 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 are 5 weather stations near enough to contribute to our estimation of the temperature and dew point in Twain Harte.
For each station, the records are corrected for the elevation difference between that station and Twain Harte 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 Twain Harte is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Twain Harte and a given station.
The stations contributing to this reconstruction are: Bridgeport Sonora Junction (21%, 72 kilometers, northeast); Modesto City-County Airport (16%, 78 kilometers, southwest); Castle Airport (17%, 79 kilometers, south); Placerville Airport (28%, 88 kilometers, northwest); and Lake Tahoe Airport (18%, 98 kilometers, north).
All data relating to the Sun's position (e.g., sunrise and sunset) are computed using astronomical formulas from the book, Astronomical Tables of the Sun, Moon and Planets , 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 aiports and weather stations are provided by AskGeo.com .
Maps are © Esri, with data from National Geographic, Esri, DeLorme, NAVTEQ, UNEP-WCMC, USGS, NASA, ESA, METI, NRCAN, GEBCO, NOAA, and iPC.