About PaintDays

Why this exists

Ask when you can paint the outside of a house and the usual answer is "spring or fall, when it is mild and dry", which is true of almost nowhere in particular. The paint can is more precise: it gives a minimum temperature, a maximum, and a warning about rain and dew. PaintDays takes those limits and counts, for 3,206 US places of 10,000 people or more, how many days in each month actually met them over the last ten years, so you can see your window, your dead months and when to call a painter.

What goes into the number

Daily weather is the NOAA Global Summary of the Day for 2015 to 2024, read from Google BigQuery's public copy: each day's low, high, mean dew point and precipitation. Each place is matched to its nearest station with enough complete years; 1,102 stations cover the 3,206 places, the median place sits 6.8 miles from its station and the farthest 73. Places and populations come from the Census Bureau's Gazetteer and population estimates.

A painting day has a low of 50°F or more, a high of 90°F or less, no measurable rain, and a mean temperature at least 5°F above the dew point. A staining day is a painting day that follows a dry day. A month is good at 12+ painting days and possible at 6+, and a 4-day house job is trusted to a month only if it averages 2× that.

What the data shows

Of the 3,206 places, 3 can paint in any month and 1,164 have a short season or none they can rely on, 64 of them with no month a house job can be trusted to. In 3,075 places, low-temperature paint (rated to 35°F) adds a month or more of workable days, which is the cheapest way there is to lengthen a season.

Known limits

An average month still has bad years in it, and a station at an airport can read differently from a hillside, a valley floor or a lakeshore a few miles away. The rules here come from standard can labels; your product's label is the one that counts. Wood moisture, wall temperature in direct sun and the age of the existing coat matter as much as the air, and none of them can be read from a weather station. Treat each page as the shape of your season, not tomorrow's forecast.

Corrections

If a place's season looks wrong to someone who paints there, say so through the contact page. Confirmed errors are fixed in the data or the model, which corrects every page that depends on it at once.

Who runs this

PaintDays is independently run. It is not affiliated with any paint brand, retailer, painting contractor, lead-referral service or government agency, and nobody pays to change a season. The site is supported by advertising, as described in the privacy policy.

Written by

Each place page is generated by AI software from the cited NOAA and Census data. No journalist or editor writes or reviews a page before it publishes. The weather records come from NOAA, not from AI; the software counts the days against the rules above and assembles the sentences around the counts.