This report describes the typical weather at the Jackson Hole Airport (Jackson Hole, Wyoming, United States) weather station over the course of an average May. It is based on the historical records from 1980 to 2012. Earlier records are either unavailable or unreliable.
Jackson Hole, Wyoming has a humid subarctic continental climate with cool summers and no dry season. The area within 25 mi of this station is covered by forests (85%), croplands (9%), grasslands (4%), and lakes and rivers (2%).
The month of May is characterized by rapidly rising daily high temperatures, with daily highs ranging from 53°F to 63°F over the course of the month, exceeding 75°F or dropping below 42°F only one day in ten.
Over the course of May, the length of the day is increasing. From the start to the end of the month, the length of the day increases by 1:02 hours, implying an average day-over-day increase of 2.0 minutes.
The shortest day of the month is May 1 with 14:11 hours of daylight; the longest day is May 31 with 15:13 hours of daylight.
The earliest sunrise is at 5:45am on May 30; the latest sunset is at 8:58pm on May 31; the latest sunrise is at 6:15am on May 1; the earliest sunset is at 8:26pm on May 1.
Daylight savings time is observed in 2012 but it neither starts nor ends in May, so the entire month is in daylight time.
The median cloud cover ranges from 50% (partly cloudy) to 67% (partly cloudy). The trend is for the sky to be clearing rapidly with the median cloud cover decreasing by 17% from the start to the end of the month.
On May 31, the clearest day of the month, the sky is clear, mostly clear, or partly cloudy 44% of the time, and overcast or mostly cloudy 34% of the time.
On May 1, the cloudiest day of the month, the sky is overcast, mostly cloudy, or partly cloudy 46% of the time, and clear or mostly clear 33% of the time.
The average probability that some form of precipitation will be observed in a given day is 23%, with little variation over the course of the month.
Throughout May, the most common forms of precipitation are light snow, light rain, and thunderstorms.
Light snow is the most severe precipitation observed during 32% of those days with precipitation. It is most likely around May 1, when it is observed during 11% of all days.
Light rain is the most severe precipitation observed during 30% of those days with precipitation. It is most likely around May 16, when it is observed during 7% of all days.
Thunderstorms are the most severe precipitation observed during 26% of those days with precipitation. They are most likely around May 31, when it is observed during 8% of all days.
The likelihood of snow falling is highest around May 1, occurring in 13% of days.
Either snow rarely accumulates at this location in May or snow depth measurements are unavailable or unreliable.
The relative humidity typically ranges from 32% (comfortable) to 85% (humid) over the course of a typical May, rarely dropping below 17% (dry) and reaching as high as 97% (very humid).
The air is driest around May 23, at which time the relative humidity drops below 40% (comfortable) three days out of four; it is most humid around May 1, rising above 79% (humid) three days out of four.
Dew point is often a better measure of how comfortable a person will find the weather than relative humidity because it more directly relates to whether perspiration will evaporate from the skin, thereby cooling the body. Lower dew points feel drier and higher dew points feel more humid.
Over the course of a typical May, the dew point typically varies from 20°F (dry) to 39°F (dry) and is rarely below 11°F (dry) or above 46°F (dry).
Over the course of May typical wind speeds vary from 0 mph to 17 mph (calm to moderate breeze), rarely exceeding 24 mph (fresh breeze).
The highest average wind speed of 8 mph (light breeze) occurs around May 2, at which time the average daily maximum wind speed is 17 mph (moderate breeze).
The lowest average wind speed of 7 mph (light breeze) occurs around May 25, at which time the average daily maximum wind speed is 16 mph (moderate breeze).