Home » Supplemental Figures for the February 2011 La Niña Drought Tracker

Supplemental Figures for the February 2011 La Niña Drought Tracker

Supplemental Figure 1. The late December storms that drenched parts of Arizona did not extend far enough east and south to reach Roswell, New Mexico. No precipitation has been measured at this weather station in at least the last 90 days, and seasonal climate forecasts indicate that dry conditions likely will continue in the next few months. However, a wet summer created a precipitation surplus during the last year in the Roswell area which will help mitigate drought impacts from a dry winter. The bottom figure displays daily precipitation. The top figure compares the cumulative totals for the last 365 days (not visible because no precipitation has fallen) to the historical average (smooth line). Figure source: NOAA-Climate Prediction Center.

 

Supplemental Figure 2. Only one meager precipitation event has been measured in El Paso, Texas, during the last 90 days. Many areas in southern New Mexico have experienced less than 25 percent of average during this period. The bottom figure displays daily precipitation. The top figure compares the cumulative totals for the last 365 days (stair-stepped line) to the historical average (smooth line). Figure source: NOAA-Climate Prediction Center.

 

Supplemental Figure 3. There has been a north-south precipitation divide this winter; cities like Las Vegas have benefitted from some powerful late-December storms, while southern portions of Arizona and New Mexico have been dry. The bottom figure displays daily precipitation. The top figure compares the cumulative totals for the last 365 days (stair-stepped line) to the historical average (smooth line). Figure source: NOAA-Climate Prediction Center.

 

Supplemental Figure 4. There has been a north-south precipitation divide this winter; cities like Cedar City, Utah, have benefitted from some powerful late-December storms, while southern portions of Arizona and New Mexico have been dry. The bottom figure displays daily precipitation. The top figure compares the cumulative totals for the last 365 days (stair-stepped line) to the historical average (smooth line). Figure source: NOAA-Climate Prediction Center.

 

Supplemental Figure 5. Based in large part on La Niña’s effect on decreasing precipitation, the January 20 Seasonal Drought Outlook calls for persisting, intensifying, and expanding drought conditions in the Southwest. Figure source: NOAA-Climate Prediction Center.

 

Supplemental Figure 6. Snow water equivalent (SWE) is currently several inches below average at the Bateman Snow Telemetry (SNOTEL) site in the Rio Chama basin in northern New Mexico. Figure source: Natural Resources Conservation Service.

 

Supplemental Figure 7. Snow water equivalent (SWE) is currently several inches below average at the Silver Creek Divide Snow Telemetry (SNOTEL) site in the Gila River basin. Figure source: Natural Resources Conservation Service.

 

Supplemental Figure 8. Snow water equivalent (SWE) is currently several inches below average at the Baldy Snow Telemetry (SNOTEL) site in the Upper Salt River in the White Mountains in east-central Arizona.

 

Supplemental Figure 9. Snow water equivalent (SWE) is currently several inches below average at Promontory Telemetry (SNOTEL) site in the Little Colorado River basin in the central Arizona. Figure source: Natural Resources Conservation Service.

 

Supplemental Figure 10. Late December storms contributed to above-average snow water equivalent at the Snowslide Canyon Snow Telemetry (SNOTEL) site in the San Francisco Peaks basin hear Flagstaff, Arizona. This basin is the only one in Arizona with above-average SWC. Figure source: Natural Resources Conservation Service.

 

Supplemental Figure 11. Spring and summer streamflow forecasts call for above-average flows in many basins in the Upper Colorado River watershed and below-average flows in many basins in Arizona and New Mexico. For example, projections for May streamflows in the Salt, Verde, and Gila river basins in Arizona call for a 50 percent chance that streamflows will be at or above 55, 76, and 39 percent of average, respectively. In the Upper Colorado River Basin, however, there is a 50 percent chance that inflow into Lake Powell will be more than 117 percent of average. Figure Source: Natural Resources Conservation Service. Figure source: Natural Resources Conservation Service.

 

Supplemental Figure 12. About 70 percent of the La Niña events between 1950 and 2008 contributed to precipitation totals between 0.4 and 2.8 inches below the February–April average in Arizona and western New Mexico. This suggests that conditions likely will be dry in the coming months, and these statistics feed the below-average precipitation forecasts and the forecasts for expanding drought issued by the NOAA-Climate Prediction Center. The image on the right displays the percent of La Niña events in which the anomalies in the left image occurred. (Ten millimeters equals about 0.4 inches). The year of La Niña events analyzed is indicated at the bottom of the figure. Figure source: NOAA-Climate Prediction Center.

 

Supplemental Figure 13. La Niña events increase chances for extreme dry conditions in the Southwest. Extreme dry conditions are defined as the driest 20 winters in the last 100 years. For February–April, all of Arizona and New Mexico have greater than a 35 percent chance of experiencing extremely dry conditions; the historical average extreme dry risk for this period is 20 percent. Figure source: NOAA–Earth Systems Research Laboratory.