This report describes the typical weather at the Flagstaff Pulliam Airport (Flagstaff, Arizona, United States) weather station over the course of an average October 12. It is based on the historical records from 1974 to 2012. Earlier records are either unavailable or unreliable.
Flagstaff, Arizona has a continental climate with dry warm summers. The area within 25 mi of this station is covered by shrublands (93%) and grasslands (6%).
The temperature typically varies from 36°F to 63°F and is rarely below 28°F or above 73°F.
The coolest hours of the day are from midnight to 8am with the coldest at 6am, at which time the temperature is below 40°F three days out of four.
The warmest hours of the day are from 10am to 6pm with the hottest at 3pm, at which time the temperature is above 58°F three days out of four.
The day has gained half its heat by 9am and lost it again by 8pm.
On October 12 the Sun rises at 6:30am and sets at 5:54pm.
Solar noon is at 12:12pm.
For reference, on the longest day of the year the Sun rises at 5:12am and sets at 7:44pm, while on the shortest day of the year it rises at 7:31am and sets at 5:19pm.
Astronomical twilight begins and ends 84 minutes before sunrise and after sunset at 5:06am and 7:19pm, respectively.
Nautical twilight begins and ends 54 minutes before sunrise and after sunset at 5:35am and 6:49pm, respectively.
Civil twilight begins and ends 25 minutes before sunrise and after sunset at 6:05am and 6:19pm, respectively.
Solar twilight begins and ends 34 minutes after sunrise and before sunset at 7:05am and 5:20pm, respectively.
The median cloud cover ranges from 1% (clear) to 21% (mostly clear).
At 1am, the clearest time of the day, the sky is clear, mostly clear, or partly cloudy 51% of the time, and overcast or mostly cloudy 10% of the time.
At 3pm, the cloudiest time of the day, the sky is overcast, mostly cloudy, or partly cloudy 40% of the time, and clear or mostly clear 55% of the time.
The sky is typically clearing in earnest by 8pm.
The clouds have typically started forming in earnest by 11am.
There is a 23% chance that precipitation will be observed at some point during the day.
The average measured liquid-equivalent quantity of precipitation is 0.041". Among only those days for which there is at least some measured precipitation, the average is 0.228" and the total rarely exceeds 0.481".
When precipitation does occur it is most often in the form of thunderstorms (38% of days with precipitation have at worst thunderstorms), slight rain (30%), slight snow (15%), and moderate rain (10%).
Precipitation is most likely around 3pm and least likely around 1am.
Either snow is exceptionally unlikely to fall at this location on October 12 or this station does not reliably report precipitation types.
The relative humidity typically ranges from 36% (comfortable) to 73% (humid), rarely dropping below 16% (dry), or exceeding 95% (very humid).
The air is driest at 3pm, at which time the relative humidity is less than 44% (comfortable) three days out of four; it is most humid at 5am, exceeding 61% (mildly humid) three days out of four.
The dew point ranges from 27°F to 32°F with an average of 28°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 3 mph to 10 mph (light air to gentle breeze) over the course of the day.
The peak sustained wind speed typically occurs around 2pm and is rarely outside the range 5 mph to 16 mph (light breeze to moderate breeze).
The wind is most calm around 4am, rarely exceeding 8 mph (light breeze).
The wind is most often out of the south west (20% of the time), north east (17% of the time), and east (10% of the time). The wind is least often out of the south east (2% of the time) and north west (3% of the time).