United States - weather in January

January is the central month of winter in the United States, and it is the coldest of the year in much of the country, except in the westernmost part (see Seattle, Los Angeles, Denver, Phoenix), where it is usually December.
The average temperatures vary a lot: they are above freezing on the west coast, facing the Pacific, quite mild even in the northern part (see Seattle), and very mild in the south (see Los Angeles), where they are spring-like. In the south, the average is above freezing as well, and in the southern tip of Florida (see Miami), where the climate is tropical, the January average is about 20 °C (68 °F).
Instead, in inland areas, January is a cold month, very cold in the north, with averages below freezing, and cold in the central area, with averages around freezing (see Kansas City) even on the Atlantic coast (see New York). The Great Lakes, on the border with Canada, can freeze to a greater or lesser extent, depending on the temperature.
Furthermore, cold waves can occur in almost the entire territory, which can significantly lower the temperature. In general, only the coast of California (see San Francisco, Los Angeles) and southern Florida (see Miami) are sheltered from cold spells. In the Great Plains the blizzard, the icy north wind, can blow, while in the Great Lakes area and in the north-east, in New England (see Boston, Portland in Maine), and sometimes also in New York and Washington, there can be snowstorms.
In the Rocky Mountains, there are several resorts where you can practice winter sports.
On the eastern side of the mountains (see Helena, Denver), the chinook can blow, a mild, dry wind capable of melting snow.
Precipitation is abundant on the northwest coast, in the states of Washington and Oregon (see Seattle), but also in northern California. On the south-central coast of California (see San Francisco, Los Angeles), the rains are gradually rarer, however, winter is the rainiest season and there can be waves of bad weather.
In the Great Basin, the arid western plateau (see Utah, Nevada and southeastern Oregon), precipitation is quite scarce, however, it can occur in the form of snow. In the Great Plains (see Fargo), east of the Great Basin, light snowfalls generally occur as well. In the deserts of the southwest (see Las Vegas, Phoenix), the rains are rare.
Instead, in the central-eastern part of the United States, precipitation is more frequent and abundant, and in the northern part, in the Great Lakes area and in New England, it often occurs in the form of snow.
The United States is located at medium latitudes, however, the days are quite short in the north, where the sun stays above the horizon for an average of 9 hours.

The sea is warm enough for swimming only in the southern tip of Florida (see Miami).


See also: United States, the weather in December - February
The climate of United States