Average Weather in New Plymouth Idaho, United States
In New Plymouth, the summers are hot and mostly clear; the winters are short, freezing, and partly cloudy; and it is dry year round. Over the course of the year, the temperature typically varies from 22°F to 93°F and is rarely below 7°F or above 100°F.
The hot season lasts for 3.0 months, from June 12 to September 13, with an average daily high temperature above 81°F. The hottest day of the year is July 27, with an average high of 93°F and low of 61°F.
The cold season lasts for 2.9 months, from November 20 to February 17, with an average daily high temperature below 46°F. The coldest day of the year is January 1, with an average low of 22°F and high of 34°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 New Plymouth, 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 New Plymouth begins around June 9 and lasts for 4.1 months, ending around October 14. On July 28, the clearest day of the year, the sky is clear, mostly clear, or partly cloudy 83% of the time, and overcast or mostly cloudy 17% of the time.
The cloudier part of the year begins around October 14 and lasts for 7.9 months, ending around June 9. On January 11, the cloudiest day of the year, the sky is overcast or mostly cloudy 60% of the time, and clear, mostly clear, or partly cloudy 40% of the time.
Cloud Cover Categories
A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. The chance of wet days in New Plymouth varies throughout the year.
The wetter season lasts 7.4 months, from October 24 to June 4, with a greater than 14% chance of a given day being a wet day. The chance of a wet day peaks at 25% on December 1.
The drier season lasts 4.6 months, from June 4 to October 24. The smallest chance of a wet day is 3% on July 28.
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 20% on November 11.
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. New Plymouth experiences some seasonal variation in monthly rainfall.
The rainy period of the year lasts for 8.6 months, from October 2 to June 21, with a sliding 31-day rainfall of at least 0.5 inches. The most rain falls during the 31 days centered around December 6, with an average total accumulation of 1.0 inches.
The rainless period of the year lasts for 3.4 months, from June 21 to October 2. The least rain falls around August 1, with an average total accumulation of 0.2 inches.
Average Monthly Rainfall
We report snowfall in liquid-equivalent terms. The actual depth of new snowfall is typically between 5 and 10 times the liquid-equivalent amount, assuming the ground is frozen. Colder, drier snow tends to be on the higher end of that range and warmer, wetter snow on the lower end.
As with rainfall, we consider the snowfall accumulated over a sliding 31-day period centered around each day of the year. New Plymouth experiences some seasonal variation in monthly liquid-equivalent snowfall.
The snowy period of the year lasts for 3.2 months, from November 13 to February 20, with a sliding 31-day liquid-equivalent snowfall of at least 0.1 inches. The most snow falls during the 31 days centered around December 26, with an average total liquid-equivalent accumulation of 0.5 inches.
The snowless period of the year lasts for 8.8 months, from February 20 to November 13. The least snow falls around July 11, with an average total liquid-equivalent accumulation of 0.0 inches.
Average Liquid-Equivalent Monthly Snowfall
The length of the day in New Plymouth varies significantly over the course of the year. In 2017, the shortest day is December 21, with 8 hours, 53 minutes of daylight; the longest day is June 20, with 15 hours, 29 minutes of daylight.
Hours of Daylight and Twilight
The earliest sunrise is at 6:03 AM on June 15, and the latest sunrise is 2 hours, 24 minutes later at 8:28 AM on November 4. The earliest sunset is at 5:09 PM on December 9, and the latest sunset is 4 hours, 25 minutes later at 9:34 PM on June 26.
Daylight saving time (DST) is observed in New Plymouth 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 New Plymouth, 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 New Plymouth experiences mild seasonal variation over the course of the year.
The windier part of the year lasts for 5.1 months, from February 18 to July 20, with average wind speeds of more than 6.5 miles per hour. The windiest day of the year is April 11, with an average hourly wind speed of 7.2 miles per hour.
The calmer time of year lasts for 6.9 months, from July 20 to February 18. The calmest day of the year is January 12, with an average hourly wind speed of 5.7 miles per hour.
Average Wind Speed
The predominant average hourly wind direction in New Plymouth varies throughout the year.
The wind is most often from the north for 7.5 months, from March 11 to October 28, with a peak percentage of 52% on July 18. The wind is most often from the east for 4.5 months, from October 28 to March 11, with a peak percentage of 40% 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 3.3 months, from May 11 to August 21, with an average daily incident shortwave energy per square meter above 6.8 kWh. The brightest day of the year is July 2, with an average of 8.1 kWh.
The darker period of the year lasts for 3.5 months, from October 30 to February 15, with an average daily incident shortwave energy per square meter below 2.8 kWh. The darkest day of the year is December 22, with an average of 1.5 kWh.
Average Daily Incident Shortwave Solar Energy
For the purposes of this report, the geographical coordinates of New Plymouth are 43.970 deg latitude, -116.819 deg longitude, and 2,257 ft elevation.
The topography within 2 miles of New Plymouth contains only modest variations in elevation, with a maximum elevation change of 154 feet and an average elevation above sea level of 2,258 feet. Within 10 miles contains only modest variations in elevation (938 feet). Within 50 miles contains very significant variations in elevation (6,253 feet).
The area within 2 miles of New Plymouth is covered by cropland (91%), within 10 miles by cropland (49%) and grassland (39%), and within 50 miles by shrubs (50%) and grassland (22%).
This report illustrates the typical weather in New Plymouth, 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 3 weather stations near enough to contribute to our estimation of the temperature and dew point in New Plymouth.
For each station, the records are corrected for the elevation difference between that station and New Plymouth 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 New Plymouth is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between New Plymouth and a given station.
The stations contributing to this reconstruction are: Ontario Municipal Airport (76%, 17 kilometers, west); Caldwell Industrial Airport (21%, 39 kilometers, southeast); and McCall Airport (3.0%, 117 kilometers, northeast).
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.
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.