About Climate by Month

What this site is

Climate by Month covers 378 US cities and travel destinations in 50 states and DC. Each city has a page for the whole year and one for every month, with normal highs and lows, wet days, humidity, snow, daylight and frost dates, and the US is ranked month by month.

The numbers describe the 1991-2020 climate: what a month is usually like, based on 30 years of observations. They are not a forecast.

Which cities are covered

The list starts from the US Census Bureau's population estimates: every city of more than 100,000 people (259 on the site), the three largest places in every state so that no state is left out, and a hand-picked set of 91 travel destinations, from Key West to Denali Park, chosen because people plan trips around their weather. 112 suburbs that use exactly the same weather stations as a larger neighbor are covered on that neighbor's page rather than repeated, and two places are left out because no suitable station is close enough.

What each page shows

• City pages: the whole year at a glance, one chart per question (how warm, how rainy, how humid, how much daylight), the best months by a published score, frost dates, records and nearby or similar places.
• Month pages: what that month is like, how it changes from the first day to the last, a typical day by the hour, how often days are wet, muggy or comfortable, how much it varies from year to year, and what to pack.
• State pages, rankings and comparisons: the same numbers side by side, for choosing between places.
• Frost dates: typical and 1-in-10-years frost dates for any ZIP code, for gardeners.

Where the numbers come from

All climate figures come from NOAA's National Centers for Environmental Information: the 1991-2020 U.S. Climate Normals, the GHCN-Daily station records and hourly observations from the Integrated Surface Database. We choose a nearby station for each kind of data and name it, with its distance and elevation, on every page. The methodology explains the rules.

The summaries are written by rules from the data, and automated tests check that every number in them matches the source. No figure is estimated by hand.

What it costs

Everything on the site is free to read, with no sign-up. There is no advertising at present.

Corrections

If a number looks wrong, or a station seems a poor match for your town, email [email protected] with the page address. We check reports against the NOAA files and correct the page or the station choice.

Who publishes this site

Climate by Month is published by the company identified in the privacy policy.