Average Weather in New Castle Indiana, United States
In New Castle, the summers are long, warm, and humid; the winters are freezing and windy; and it is partly cloudy year round. Over the course of the year, the temperature typically varies from 21°F to 83°F and is rarely below 3°F or above 90°F.
Based on the tourism score, the best time of year to visit New Castle for warm-weather activities is from mid June to mid September.
The warm season lasts for 4.0 months, from May 21 to September 23, with an average daily high temperature above 73°F. The hottest day of the year is July 19, with an average high of 83°F and low of 65°F.
The cold season lasts for 3.0 months, from December 1 to March 2, with an average daily high temperature below 44°F. The coldest day of the year is January 29, with an average low of 21°F and high of 35°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 Castle, 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 Castle begins around June 13 and lasts for 4.6 months, ending around October 31. On August 23, the clearest day of the year, the sky is clear, mostly clear, or partly cloudy 69% of the time, and overcast or mostly cloudy 31% of the time.
The cloudier part of the year begins around October 31 and lasts for 7.4 months, ending around June 13. On January 2, the cloudiest day of the year, the sky is overcast or mostly cloudy 61% of the time, and clear, mostly clear, or partly cloudy 39% 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 Castle varies throughout the year.
The wetter season lasts 4.9 months, from March 25 to August 20, with a greater than 30% chance of a given day being a wet day. The chance of a wet day peaks at 41% on June 26.
The drier season lasts 7.1 months, from August 20 to March 25. The smallest chance of a wet day is 19% on January 29.
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 41% on June 26.
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 Castle experiences significant seasonal variation in monthly rainfall.
Rain falls throughout the year in New Castle. The most rain falls during the 31 days centered around June 2, with an average total accumulation of 4.0 inches.
The least rain falls around February 5, with an average total accumulation of 1.5 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 Castle experiences some seasonal variation in monthly liquid-equivalent snowfall.
The snowy period of the year lasts for 4.2 months, from November 23 to March 30, with a sliding 31-day liquid-equivalent snowfall of at least 0.1 inches. The most snow falls during the 31 days centered around February 5, with an average total liquid-equivalent accumulation of 0.4 inches.
The snowless period of the year lasts for 7.8 months, from March 30 to November 23. The least snow falls around July 18, with an average total liquid-equivalent accumulation of 0.0 inches.
Average Liquid-Equivalent Monthly Snowfall
The length of the day in New Castle varies significantly over the course of the year. In 2017, the shortest day is December 21, with 9 hours, 20 minutes of daylight; the longest day is June 21, with 15 hours, 1 minute of daylight.
Hours of Daylight and Twilight
The earliest sunrise is at 6:12 AM on June 13, and the latest sunrise is 2 hours, 2 minutes later at 8:14 AM on November 4. The earliest sunset is at 5:16 PM on December 7, and the latest sunset is 3 hours, 58 minutes later at 9:14 PM on June 27.
Daylight saving time (DST) is observed in New Castle 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
New Castle experiences extreme seasonal variation in the perceived humidity.
The muggier period of the year lasts for 3.7 months, from May 28 to September 19, during which time the comfort level is muggy, oppressive, or miserable at least 14% of the time. The muggiest day of the year is July 23, with muggy conditions 55% of the time.
The least muggy day of the year is February 10, when muggy conditions are essentially unheard of.
Humidity Comfort Levels
The average hourly wind speed in New Castle experiences significant seasonal variation over the course of the year.
The windier part of the year lasts for 7.4 months, from October 10 to May 22, with average wind speeds of more than 9.7 miles per hour. The windiest day of the year is January 15, with an average hourly wind speed of 12.4 miles per hour.
The calmer time of year lasts for 4.6 months, from May 22 to October 10. The calmest day of the year is August 4, with an average hourly wind speed of 6.9 miles per hour.
Average Wind Speed
The predominant average hourly wind direction in New Castle varies throughout the year.
The wind is most often from the south for 2.4 months, from April 6 to June 18 and for 3.2 months, from August 22 to November 29, with a peak percentage of 38% on November 14. The wind is most often from the west for 2.1 months, from June 18 to August 22 and for 4.2 months, from November 29 to April 6, with a peak percentage of 37% on July 20.
Best Time of Year to Visit
To characterize how pleasant the weather is in New Castle 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 time of year to visit New Castle for general outdoor tourist activities is from mid June to mid September, with a peak score in the last week of August.
The beach/pool score favors clear, rainless days with perceived temperatures between 75°F and 90°F. Based on this score, the best time of year to visit New Castle for hot-weather activities is from late June to late August, with a peak score in the third week of July.
For 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.
The growing season in New Castle typically lasts for 6.0 months (185 days), from around April 16 to around October 18, rarely starting before March 31 or after May 2, and rarely ending before September 28 or after November 5.
Time Spent in Various Temperature Bands and the Growing Season
Based on growing degree days alone, the first spring blooms in New Castle should appear around April 4, only rarely appearing before March 18 or after April 19.
Growing Degree Days
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 4.0 months, from April 30 to August 30, with an average daily incident shortwave energy per square meter above 5.8 kWh. The brightest day of the year is July 2, with an average of 6.8 kWh.
The darker period of the year lasts for 3.1 months, from November 5 to February 10, with an average daily incident shortwave energy per square meter below 2.8 kWh. The darkest day of the year is December 18, with an average of 1.8 kWh.
Average Daily Incident Shortwave Solar Energy
For the purposes of this report, the geographical coordinates of New Castle are 39.929 deg latitude, -85.370 deg longitude, and 1,060 ft elevation.
The topography within 2 miles of New Castle contains only modest variations in elevation, with a maximum elevation change of 148 feet and an average elevation above sea level of 1,038 feet. Within 10 miles also contains only modest variations in elevation (289 feet). Within 50 miles contains only modest variations in elevation (922 feet).
The area within 2 miles of New Castle is covered by cropland (47%) and artificial surfaces (47%), within 10 miles by cropland (92%), and within 50 miles by cropland (86%).
This report illustrates the typical weather in New Castle, 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 6 weather stations near enough to contribute to our estimation of the temperature and dew point in New Castle.
For each station, the records are corrected for the elevation difference between that station and New Castle 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 Castle is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between New Castle and a given station.
The stations contributing to this reconstruction are: Delaware County Regional Airport (40%, 34 kilometers, north); Shelbyville Municipal Airport (20%, 54 kilometers, southwest); Indianapolis Executive Airport (12%, 76 kilometers, west); Darke County Airport (12%, 78 kilometers, northeast); Middletown Regional Airport/Hook Field (9%, 95 kilometers, southeast); and Butler County Regional Airport (8%, 96 kilometers, southeast).
Time zones for aiports and weather stations are provided by AskGeo.com .