Average Weather at Keokuk Municipal Airport Iowa, United States
At Keokuk Municipal Airport, the summers are warm, humid, and wet; the winters are freezing and windy; and it is partly cloudy year round. Over the course of the year, the temperature typically varies from 20°F to 87°F and is rarely below 2°F or above 95°F.
Based on the tourism score, the best time of year to visit Keokuk Municipal Airport for warm-weather activities is from early June to late September.
The hot season lasts for 3.8 months, from May 25 to September 19, with an average daily high temperature above 77°F. The hottest day of the year is July 20, with an average high of 87°F and low of 69°F.
The cold season lasts for 3.1 months, from November 29 to March 1, with an average daily high temperature below 46°F. The coldest day of the year is January 22, with an average low of 20°F and high of 36°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
At Keokuk Municipal Airport, 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 at Keokuk Municipal Airport begins around June 12 and lasts for 4.4 months, ending around October 25. On August 26, the clearest day of the year, the sky is clear, mostly clear, or partly cloudy 70% of the time, and overcast or mostly cloudy 30% of the time.
The cloudier part of the year begins around October 25 and lasts for 7.6 months, ending around June 12. On February 12, the cloudiest day of the year, the sky is overcast or mostly cloudy 55% of the time, and clear, mostly clear, or partly cloudy 45% 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 at Keokuk Municipal Airport varies throughout the year.
The wetter season lasts 5.7 months, from March 31 to September 21, with a greater than 26% chance of a given day being a wet day. The chance of a wet day peaks at 41% on June 7.
The drier season lasts 6.3 months, from September 21 to March 31. The smallest chance of a wet day is 12% on January 26.
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 7.
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. Keokuk Municipal Airport experiences significant seasonal variation in monthly rainfall.
Rain falls throughout the year at Keokuk Municipal Airport. The most rain falls during the 31 days centered around June 2, with an average total accumulation of 4.3 inches.
The least rain falls around January 20, with an average total accumulation of 0.6 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. Keokuk Municipal Airport experiences some seasonal variation in monthly liquid-equivalent snowfall.
The snowy period of the year lasts for 3.7 months, from November 22 to March 13, with a sliding 31-day liquid-equivalent snowfall of at least 0.1 inches. The most snow falls during the 31 days centered around January 29, with an average total liquid-equivalent accumulation of 0.3 inches.
The snowless period of the year lasts for 8.3 months, from March 13 to November 22. The least snow falls around July 19, with an average total liquid-equivalent accumulation of 0.0 inches.
Average Liquid-Equivalent Monthly Snowfall
The length of the day at Keokuk Municipal Airport varies significantly over the course of the year. In 2018, the shortest day is December 21, with 9 hours, 17 minutes of daylight; the longest day is June 21, with 15 hours, 4 minutes of daylight.
Hours of Daylight and Twilight
The earliest sunrise is at 5:34 AM on June 14, and the latest sunrise is 2 hours, 3 minutes later at 7:37 AM on November 3. The earliest sunset is at 4:38 PM on December 8, and the latest sunset is 4 hours, 1 minute later at 8:40 PM on June 27.
Daylight saving time (DST) is observed at Keokuk Municipal Airport 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
Keokuk Municipal Airport experiences extreme seasonal variation in the perceived humidity.
The muggier period of the year lasts for 3.9 months, from May 24 to September 20, during which time the comfort level is muggy, oppressive, or miserable at least 15% of the time. The muggiest day of the year is July 22, with muggy conditions 60% of the time.
The least muggy day of the year is December 11, when muggy conditions are essentially unheard of.
Humidity Comfort Levels
The average hourly wind speed at Keokuk Municipal Airport experiences significant seasonal variation over the course of the year.
The windier part of the year lasts for 7.4 months, from October 9 to May 23, with average wind speeds of more than 9.9 miles per hour. The windiest day of the year is April 1, with an average hourly wind speed of 12.4 miles per hour.
The calmer time of year lasts for 4.6 months, from May 23 to October 9. The calmest day of the year is August 6, with an average hourly wind speed of 7.5 miles per hour.
Average Wind Speed
The predominant average hourly wind direction at Keokuk Municipal Airport varies throughout the year.
The wind is most often from the north for 1.8 months, from February 9 to April 3, with a peak percentage of 32% on March 8. The wind is most often from the south for 7.9 months, from April 3 to December 1, with a peak percentage of 40% on September 7. The wind is most often from the west for 2.3 months, from December 1 to February 9, with a peak percentage of 35% on January 1.
Best Time of Year to Visit
To characterize how pleasant the weather is at Keokuk Municipal Airport 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 Keokuk Municipal Airport for general outdoor tourist activities is from early June to late 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 Keokuk Municipal Airport 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 at Keokuk Municipal Airport typically lasts for 6.6 months (202 days), from around April 8 to around October 27, rarely starting before March 22 or after April 25, and rarely ending before October 7 or after November 16.
Time Spent in Various Temperature Bands and the Growing Season
Based on growing degree days alone, the first spring blooms at Keokuk Municipal Airport should appear around March 29, only rarely appearing before March 15 or after April 16.
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 3.8 months, from May 1 to August 26, with an average daily incident shortwave energy per square meter above 5.9 kWh. The brightest day of the year is July 2, with an average of 6.9 kWh.
The darker period of the year lasts for 3.2 months, from November 3 to February 10, with an average daily incident shortwave energy per square meter below 2.9 kWh. The darkest day of the year is December 21, with an average of 1.9 kWh.
Average Daily Incident Shortwave Solar Energy
For the purposes of this report, the geographical coordinates of Keokuk Municipal Airport are 40.460 deg latitude, -91.428 deg longitude, and 636 ft elevation.
The topography within 2 miles of Keokuk Municipal Airport contains only modest variations in elevation, with a maximum elevation change of 141 feet and an average elevation above sea level of 640 feet. Within 10 miles also contains only modest variations in elevation (266 feet). Within 50 miles also contains only modest variations in elevation (463 feet).
The area within 2 miles of Keokuk Municipal Airport is covered by cropland (57%) and trees (40%), within 10 miles by cropland (65%) and trees (23%), and within 50 miles by cropland (79%) and trees (18%).
This report illustrates the typical weather at Keokuk Municipal Airport, 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
Keokuk Municipal Airport has a weather station that reported reliably enough during the analysis period that we have included it in our network. When available, historical temperature and dew point measurements are taken directly from this weather station. These records are obtained from NOAA's Integrated Surface Hourly data set, falling back on ICAO METAR records as required.
In the case of missing or erroneous measurements from this station, we fall back on records from nearby stations, adjusted according to typical seasonal and diurnal intra-station differences. For a given day of the year and hour of the day, the fallback station is selected to minimize the prediction error over the years for which there are measurements for both stations.
The stations on which we may fall back include but are not limited to Fort Madison Municipal Airport, Burlington Municipal Airport, Mount Pleasant Municipal Airport, Quincy Regional Airport, Macomb Municipal Airport, Fairfield Municipal Airport, Washington Municipal Airport, and Muscatine Municipal Airport.
Time zones for aiports and weather stations are provided by AskGeo.com .