This report describes the typical weather at the Idaho Falls Regional Airport (Idaho Falls, United States) weather station over the course of an average October 5. It is based on the historical records from 1974 to 2012. Earlier records are either unavailable or unreliable.
Idaho Falls, Idaho has a cold semi-arid steppe climate. The area within 25 mi of this station is covered by croplands (38%), forests (22%), shrublands (21%), and grasslands (19%).
The temperature typically varies from 37°F to 64°F and is rarely below 29°F or above 76°F.
The coolest hours of the day are from 2am to 9am with the coldest at 7am, at which time the temperature is below 42°F three days out of four.
The warmest hours of the day are from 1pm to 7pm with the hottest at 4pm, at which time the temperature is above 57°F three days out of four.
The day has gained half its heat by 11am and lost it again by 10pm.
On October 5 the Sun rises at 7:30am and sets at 7:00pm.
Solar noon is at 1:16pm.
For reference, on the longest day of the year the Sun rises at 5:47am and sets at 9:12pm, while on the shortest day of the year it rises at 7:58am and sets at 4:55pm.
Astronomical twilight begins and ends 95 minutes before sunrise and after sunset at 5:56am and 8:36pm, respectively.
Nautical twilight begins and ends 61 minutes before sunrise and after sunset at 6:29am and 8:02pm, respectively.
Civil twilight begins and ends 28 minutes before sunrise and after sunset at 7:02am and 7:29pm, respectively.
Solar twilight begins and ends 38 minutes after sunrise and before sunset at 8:09am and 6:22pm, respectively.
The median cloud cover ranges from 12% (mostly clear) to 52% (partly cloudy).
At 2am, the clearest time of the day, the sky is clear, mostly clear, or partly cloudy 63% of the time, and overcast or mostly cloudy 27% of the time.
At 3pm, the cloudiest time of the day, the sky is overcast, mostly cloudy, or partly cloudy 58% of the time, and clear or mostly clear 42% of the time.
The sky is typically clearing in earnest by 9pm.
The clouds have typically started forming in earnest by 8am.
There is a 22% chance that precipitation will be observed at some point during the day.
The average measured liquid-equivalent quantity of precipitation is 0.008". Among only those days for which there is at least some measured precipitation, the average is 0.140" and the total rarely exceeds 0.200".
When precipitation does occur it is most often in the form of slight rain (54% of days with precipitation have at worst slight rain), slight snow (18%), thunderstorms (15%), and moderate rain (7%).
Precipitation is most likely around 9am and least likely around midnight.
Either snow is exceptionally unlikely to fall at this location on October 5 or this station does not reliably report precipitation types.
The relative humidity typically ranges from 38% (comfortable) to 78% (humid), rarely dropping below 19% (dry), or exceeding 100% (very humid).
The air is driest at 4pm, at which time the relative humidity is less than 46% (comfortable) three days out of four; it is most humid at 6am, exceeding 69% (mildly humid) three days out of four.
The dew point ranges from 31°F to 34°F with an average of 32°F.
For reference, comfortable indoor conditions should have a relative humidity between 30% and 50% with a dew point of less than 65°F.
Sustained wind speeds typically vary from 7 mph to 12 mph (light breeze to gentle breeze) over the course of the day.
The peak sustained wind speed typically occurs around 4pm and is rarely outside the range 4 mph to 21 mph (light breeze to fresh breeze).
The wind is most calm around 5am, rarely exceeding 12 mph (moderate breeze).
The wind is most often out of the south west (25% of the time), north (21% of the time), and south (20% of the time). The wind is least often out of the east (1% of the time), south east (2% of the time), north east (4% of the time), west (4% of the time), and north west (5% of the time).