Southwest Climate Outlook March 2010

March Climate Summary
Drought– Drought conditions continued to improve across the Southwest, and most of southern Arizona and New Mexico are either only abnormally dry or drought free.
Temperature– A series of cold fronts in February and March brought cooler conditions to the Southwest.
Precipitation– Most of the Southwest remains much wetter than average with significant snowpack as the strong El Niño circulation continues.
ENSO– Moderate El Niño conditions persisted across the equatorial Pacific Ocean again this month and are expected to continue over the next month or two. The chance of ENSO-neutral conditions returning increases by later this spring.
Climate Forecasts– Historical temperature trends contribute to warm seasonal outlooks—there is more than a 50 percent chance that temperatures during the May–July and July–September periods will be similar to the warmest 10 years of
the 1971–2000 record. Precipitation outlooks for the April–June period indicate slightly elevated chances that conditions in northern Arizona and New Mexico will be similar to the wettest 10 years of the 1971–2000 period.
The Bottom Line– El Niño once again helped steer winter storms into Arizona and New Mexico. Profuse snow and rain continued to improve drought conditions, build snowpack, and increase projections of spring streamflows. Snowpack is nearly twice the historic average in many high elevation regions in Arizona and many reservoirs in the state are more than 88 percent full; Roosevelt Lake reached record high levels on March 12. El Niño may continue to bring wet weather, as forecasts suggest the event will likely continue through April. While rain and snow have improved winter vegetation growth, summer growth will need a healthy monsoon season. In other words, short-term drought conditions can come and go rapidly.