Average Weather in Rockville Minnesota, United States
In Rockville, the summers are long, warm, and wet; the winters are freezing, snowy, and windy; and it is partly cloudy year round. Over the course of the year, the temperature typically varies from 5°F to 82°F and is rarely below -17°F or above 90°F.
Based on the tourism score, the best time of year to visit Rockville for warm-weather activities is from late June to late August.
The warm season lasts for 3.9 months, from May 20 to September 17, with an average daily high temperature above 69°F. The hottest day of the year is July 18, with an average high of 82°F and low of 61°F.
The cold season lasts for 3.3 months, from November 26 to March 4, with an average daily high temperature below 33°F. The coldest day of the year is January 20, with an average low of 5°F and high of 21°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 Rockville, 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 Rockville begins around June 9 and lasts for 4.2 months, ending around October 14. On July 28, the clearest day of the year, the sky is clear, mostly clear, or partly cloudy 72% of the time, and overcast or mostly cloudy 28% of the time.
The cloudier part of the year begins around October 14 and lasts for 7.8 months, ending around June 9. On February 6, 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
0% clear 20% mostly clear 40% partly cloudy 60% mostly cloudy 80% overcast 100%
A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. The chance of wet days in Rockville varies significantly throughout the year.
The wetter season lasts 5.5 months, from April 21 to October 3, with a greater than 24% chance of a given day being a wet day. The chance of a wet day peaks at 40% on June 13.
The drier season lasts 6.6 months, from October 3 to April 21. The smallest chance of a wet day is 7% on January 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 in Rockville changes throughout the year.
Rain alone is the most common for 8.4 months, from March 12 to November 22. The highest chance of a day with rain alone is 40% on June 13.
Snow alone is the most common for 3.6 months, from November 22 to March 12. The highest chance of a day with snow alone is 7% on December 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. Rockville experiences extreme seasonal variation in monthly rainfall.
The rainy period of the year lasts for 8.5 months, from March 8 to November 25, with a sliding 31-day rainfall of at least 0.5 inches. The most rain falls during the 31 days centered around June 19, with an average total accumulation of 4.1 inches.
The rainless period of the year lasts for 3.5 months, from November 25 to March 8. The least rain falls around January 25, with an average total accumulation of 0.1 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. Rockville experiences some seasonal variation in monthly liquid-equivalent snowfall.
The snowy period of the year lasts for 6.1 months, from October 25 to April 27, with a sliding 31-day liquid-equivalent snowfall of at least 0.1 inches. The most snow falls during the 31 days centered around March 4, with an average total liquid-equivalent accumulation of 0.5 inches.
The snowless period of the year lasts for 5.9 months, from April 27 to October 25. The least snow falls around July 22, with an average total liquid-equivalent accumulation of 0.0 inches.
Average Liquid-Equivalent Monthly Snowfall
The length of the day in Rockville varies significantly over the course of the year. In 2018, the shortest day is December 21, with 8 hours, 42 minutes of daylight; the longest day is June 21, with 15 hours, 41 minutes of daylight.
Hours of Daylight and Twilight
The earliest sunrise is at 5:28 AM on June 15, and the latest sunrise is 2 hours, 32 minutes later at 7:59 AM on November 3. The earliest sunset is at 4:33 PM on December 10, and the latest sunset is 4 hours, 36 minutes later at 9:10 PM on June 26.
Daylight saving time (DST) is observed in Rockville during 2018, starting in the spring on March 11, lasting 7.8 months, and ending in the fall on November 4.
Sunrise & Sunset with Twilight and Daylight Saving Time
Rockville experiences some seasonal variation in the perceived humidity.
The muggier period of the year lasts for 3.1 months, from June 11 to September 14, during which time the comfort level is muggy, oppressive, or miserable at least 7% of the time. The muggiest day of the year is July 20, with muggy conditions 29% of the time.
The least muggy day of the year is December 9, when muggy conditions are essentially unheard of.
Humidity Comfort Levels
dry 55°F comfortable 60°F humid 65°F muggy 70°F oppressive 75°F miserable
The average hourly wind speed in Rockville experiences significant seasonal variation over the course of the year.
The windier part of the year lasts for 8.4 months, from September 17 to May 28, with average wind speeds of more than 10.7 miles per hour. The windiest day of the year is April 2, with an average hourly wind speed of 12.6 miles per hour.
The calmer time of year lasts for 3.6 months, from May 28 to September 17. The calmest day of the year is August 1, with an average hourly wind speed of 8.7 miles per hour.
Average Wind Speed
The predominant average hourly wind direction in Rockville varies throughout the year.
The wind is most often from the north for 4.1 months, from January 5 to May 9, with a peak percentage of 35% on April 12. The wind is most often from the south for 6.2 months, from May 9 to November 14, with a peak percentage of 40% on August 27. The wind is most often from the west for 1.7 months, from November 14 to January 5, with a peak percentage of 33% on January 1.
Best Time of Year to Visit
To characterize how pleasant the weather is in Rockville 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 Rockville for general outdoor tourist activities is from late June to late August, with a peak score in the last week of July.
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 Rockville for hot-weather activities is from early July to early 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 Rockville typically lasts for 5.0 months (151 days), from around May 3 to around October 2, rarely starting before April 15 or after May 23, and rarely ending before September 14 or after October 19.
Time Spent in Various Temperature Bands and the Growing Season
Based on growing degree days alone, the first spring blooms in Rockville should appear around April 28, only rarely appearing before April 17 or after May 12.
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 3.5 months, from May 5 to August 20, with an average daily incident shortwave energy per square meter above 5.9 kWh. The brightest day of the year is July 10, with an average of 7.1 kWh.
The darker period of the year lasts for 3.4 months, from October 29 to February 11, with an average daily incident shortwave energy per square meter below 2.5 kWh. The darkest day of the year is December 20, with an average of 1.4 kWh.
Average Daily Incident Shortwave Solar Energy
For the purposes of this report, the geographical coordinates of Rockville are 45.472 deg latitude, -94.341 deg longitude, and 1,122 ft elevation.
The topography within 2 miles of Rockville contains only modest variations in elevation, with a maximum elevation change of 184 feet and an average elevation above sea level of 1,116 feet. Within 10 miles contains only modest variations in elevation (499 feet). Within 50 miles also contains significant variations in elevation (659 feet).
The area within 2 miles of Rockville is covered by cropland (67%) and trees (33%), within 10 miles by cropland (69%) and trees (20%), and within 50 miles by cropland (77%) and trees (15%).
This report illustrates the typical weather in Rockville, 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 Rockville.
For each station, the records are corrected for the elevation difference between that station and Rockville 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 Rockville is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between Rockville and a given station.
The stations contributing to this reconstruction are: St. Cloud Regional Airport (34%, 24 kilometers, east); Paynesville Municipal Airport (21%, 34 kilometers, west); Maple Lake Municipal Airport (17%, 38 kilometers, southeast); Litchfield Municipal Airport (17%, 38 kilometers, south); and Little Falls, Little Falls/Morrison County Airport-Lindbergh Field (11%, 53 kilometers, north).
Time zones for aiports and weather stations are provided by AskGeo.com .