Precipitation

temp-precip

Precipitation

Photo courtesy of Philip Tarrant
Photo courtesy of Philip Tarrant

Arizona receives the majority of annual precipitation during two seasons: summer (monsoon season) and winter. Winter precipitation comes from cold fronts and low pressure systems. These systems move south from the Pacific Northwest, often sweeping across Nevada or southern California before bringing cold air and rain or snow into Arizona.

The northern half of the state as well as higher elevations across the state typically receive snowfall in the winter. Northern Arizona receives just over half their annual precipitation in the winter.

The winter storms occasionally extend into southern Arizona, however, southern Arizona receives most of their annual precipitation in the summer. Winter storms rarely bring snow to southern Arizona, but at the highest elevations, like Mount Lemmon in Tucson, snow is not uncommon in the winter.

Arizona’s reservoirs largely rely on winter precipitation to refill.
 
 

Arizona Reservoirs


 

Salt River Project (SRP) Daily Water Report

Current water levels on Lake Mead and Lake Powell

 

Excessive Rainfall Outlook

Outlook Day 1 (today)

Outlook Day 2 (tomorrow)

Outlook Day 3 (next day)

 

Daily Precipitation

Arizona Daily Precipitation

 

Monthly Precipitation

Arizona Monthly Precipitation

 

Water Year Precipitation

PRISM WY Precipitation Anomaly

 

Seasonal Precipitation Colorado River Basin

 

Snow Water Equivalent

Upper Colorado Basin
Lower Colorado Basin

 
 

Normal Annual Snowfall

SPC legendSPC legend

 
 

  • Arizona Annual Precipitation Map