Southwest Climate Outlook April 2009

April Climate Summary
Drought– Short-term drought conditions remained unchanged across northern Arizona, while worsening conditions were observed over the southeastern quarter of the state. For New Mexico, worsening drought conditions continued again this month; more than 60 percent of the state is experiencing some level of drought.
Temperature– The past 30 days brought a series of fairly dry cold fronts to the northern half of New Mexico and the northeast and northwest corners of Arizona, dropping temperatures as much as 3 degrees below average.
Precipitation– In the past 30 days, many parts of Arizona, and southern New Mexico had less than 25 percent of their average precipitation. Average precipitation since October 1 in many regions of both states has been less than 70 percent.
ENSO– The La Niña of 2008–2009 is almost over, and forecasts strongly support a quick move towards ENSO-neutral conditions over the next several months.
Climate Forecasts– The long-lead forecasts indicate the Southwest has increased chances for summer temperatures to be similar to the warmest 10 years of 1971–2000 and increased chances for precipitation through October to be similar to the wettest 10 years of 1971–2000.
The Bottom Line– Precipitation has been scant during the past 30 days. Mid-March to mid-April delivered less than 70 percent of average precipitation to most of the Southwest and only slightly more rainfall than mid-February to mid-March totals. As a result, drought conditions have expanded. Because April–June historically is very dry, the next sustained precipitation will likely not occur until the monsoon season begins.