When it comes to precipitation, there are many factors that can affect whether it rains or snows. Two of the most important factors are humidity and location.

Relative humidity is the amount of water vapor in the air compared to the maximum amount of water vapor that the air can hold at a given temperature. The higher the relative humidity, the more likely it is to rain or snow.

Location also plays a role in precipitation. The closer a location is to a body of water, the more likely it is to experience rain or snow. This is because bodies of water release water vapor into the air, which can then condense and form clouds.

The map above shows the average annual precipitation for the United States. The areas in blue receive the most precipitation, while the areas in red receive the least precipitation. The map also shows the average annual relative humidity for the United States. The areas in green have the highest relative humidity, while the areas in yellow have the lowest relative humidity.

As you can see from the map, there is a strong correlation between precipitation and relative humidity. The areas with the highest relative humidity also receive the most precipitation. This is because the higher the relative humidity, the more likely it is for water vapor to condense and form clouds.

Location also plays a role in precipitation. The areas closest to the oceans and the Great Lakes receive the most precipitation. This is because these bodies of water release water vapor into the air, which can then condense and form clouds.

The map above can be used to help predict whether it is more likely to rain or snow in a particular location. If the relative humidity is high and the location is near a body of water, it is more likely to rain. If the relative humidity is low and the location is far from a body of water, it is more likely to snow.

Of course, there are other factors that can affect precipitation, such as temperature and wind speed. However, relative humidity and location are two of the most important factors to consider when predicting whether it is more likely to rain or snow.