Forecasts and Outlooks > Archive
Southwest Climate Outlook - March 2004

Date issued: March 26, 2004

A. Summary

Highlights

• New Mexico reservoirs are at well-below-average levels, although February and March snowfall resulted in gains at most reservoirs.

•Storage in the major Colorado River reservoirs remains well below average.

•Salt and Verde River Basin reservoirs remain well below average.

Temperatures - During the past 30 days, temperatures have been above average across the Southwest—breaking records at many stations.

Precipitation - Recent precipitation, while beneficial in the short-term, is not sufficient to overcome multi-year precipitation and soil moisture deficits. Prior to recent and rapid melt, Arizona and New Mexico snowpacks were below average—thus spring/summer streamflows across the region are projected to be below average. Moreover, current snowpack is below average throughout the Upper Colorado and Upper Rio Grande River Basins.

Climate Forecasts - Seasonal forecasts indicate increased probabilities of above-average temperatures across Arizona and New Mexico through the spring and summer months. Increased temperature implies increased evapotranspiration. Precipitation forecasts do not suggest strong probability anomalies for either above- or below-average precipitation. The U.S. Drought Outlook suggests persistent drought conditions for virtually all of Arizona and New Mexico.

ENSO - ENSO conditions are neutral and will likely remain neutral during the first half of 2004. This means greater forecast uncertainty.

· Bottom line: In the absence of exceptional precipitation during the next month, hydrological drought will persist in the Southwest. Temperatures have been warmer than average and those soils are thirsty!

• The most likely scenario is that, despite February and March precipitation in the Southwest, there is no indication that most of the Southwest will receive drought-ending precipitation during the next several months. Recent temperature increases, if persistent, will increase fire danger. Reservoir levels might show short-term increases due to snowmelt, but late spring and summer precipitation are not expected to have major positive impacts on water supply.

•The worst case scenario is that for 2004 we have seen the last of winter storms that yield substantial precipitation. Above-average temperatures persist and there is a rapid escalation of fire danger. Reservoir levels continue to decline beyond expectations.

•The best case scenario is that we have a repeat of spring 1999 – where a spring snowstorm blanketed parts of our region – substantially reducing fire danger for months.

B. Recent Conditions >