Precipitation



Precipitation is any form of water, liquid or solid, that falls from clouds and reaches the ground. This includes drizzle, freezing drizzle, freezing  rain, hail, ice crystals, ice pellets, rain, snow, snow pellets, and snow grains. The amount of precipitation is usually expressed in inches of liquid water depth of the substance that has fallen at a given point over a specified time period.

The average number of days per month with rainfall is 9, with a range of 6 days in October to 13 days in July.  On the average, measurable amounts occur 107 days a year.  The average annual precipitation is 59.9 inches. May and November are the driest months, and July and September are the wettest months. Approximately 2.5 of the rainfall in September can be attributed to tropical systems.

During the summer, most of the rainfall occurs during daylight hours in the form of thunderstorms, and is often excessive. The lowest percentage of precipitation occurring at night throughout theUnited States occurs along the Gulf Coast, where less than 35% of the total amount falls between 1900 and 0700 local time. Generally speaking, thunderstorms that form over the Gulf and move inland produce heavy precipitation and occasionally severe weather.

Rainfall during the winter months is typically not as heavy and extends over longer periods of time. Solid precipitation in the form of snow, snow pellets, and sleet are rarities in the local area, occurring on the average of once a year.  

Concept Mapping Toolkit
Insitute for Human and Machine Cognition
The University of West Florida