Home » July 2012 Southwest Climate Outlook
Published July 25, 2012

July 2012 Climate Summary

 

Drought: Drought conditions did not change much during the past 30 days. About 94 and 80 percent of Arizona and New Mexico, respectively, are classified with at least severe drought.

Temperature: Early and continuous monsoon activity has broken the heat over western and southern Arizona, while eastern New Mexico continues to bake.

Precipitation: Vigorous monsoon activity has helped deliver above-average precipitation to some parts of Arizona. However, the monsoon has yet to kick in with full force in southern New Mexico. 
 
ENSO: An El Niño Watch remains in effect this month as sea surface temperatures continue to warm and spread across the eastern equatorial Pacific Ocean. Weak to moderate El Niño conditions are expected to develop in the fall.   
 
Climate Forecasts: Forecast models favor above-average precipitation and temperatures in many parts of the Southwest through the monsoon.  
 
The Bottom Line: Summer precipitation arrived in southern Arizona earlier than average and has delivered copious rain to many areas. Vigorous monsoon activity has helped suppress wildland fires and reduce the risk of new blazes. However, like always, the monsoon has soaked some places while leaving others dry. Southwestern New Mexico, for example, has not yet received a hefty summer dousing, as the position of the monsoon high has impeded a continuous stream of moisture into the region. Also, while the first month of the monsoon generally has been good across the region, it is still early and forecasters are reticent to declare improved drought conditions until additional moisture falls. As a result, Arizona and New Mexico have about the same drought classifications as they did one month ago. Severe drought or a more extreme drought category currently covers about 94 percent of Arizona, while about 80 percent of New Mexico is labeled with these conditions. Short-term drought relief, however, may be on the horizon. The NOAA-Climate Prediction Center calls for slightly increased chances for above-average rain in coming months. Copious rains will need to persist into the winter and possibly longer to improve drought impacts related to water supply, like reservoir storage. After a dry winter, for example, total streamflow in the Colorado River during this water year is expected to be about 46 percent of average, which will be its third lowest water year on record. Also, streamflows on the Rio Grande will be well below average. The winter precipitation outlook favors some improvement in drought. Forecasts call for an El Niño event to materialize in coming months, which will increase chances for a wet winter.

News Flash: Are Recent Extremes and Global Warming Related?

It has been a hot 2012. The year has experienced the warmest January–June period on record in the U.S., and more than 25,000 maximum daily temperatures were eclipsed between January 1 and July 18. These extreme conditions are a continuation from last year—2011 earned the moniker “the year of billion-dollar disasters,” which included devastating drought in the Southwest. The recent extreme conditions across the country have many people inquiring if these events relate to global warming. Until recently, scientists said it is not possible to attribute a single event to climate change. Now, however, it is widely accepted that linking individual events to climate change is tenable.
 
While not every event is linked to climate change, long-term warming has played a part in some instances. A compilation of analyses, the first edition of what is to be an annual report, helps answer if human actions contributed to select extreme events. The report, “Explaining Extreme Events of 2011 from a Climate Perspective,” analyzed six events, including the drought that besieged the southern tier of the U.S. in 2011. According to the report, conditions that led to the Texas portion of this drought are now distinctly more probable than they were 40–50 years ago because of recent global warming. As for the extreme heat this year, we’ll have to wait until next July’s report for an answer.