Home » Supplemental Figures for the March 2012 La Niña Drought Tracker

Supplemental Figures for the March 2012 La Niña Drought Tracker

Supplemental Figure 1. Less than 70 percent of average precipitation fell in most of Arizona in February, while New Mexico faired only slightly better. Source: High Plains Regional Climate Center

Supplemental Figure 2. Many parts of Arizona and New Mexico have experienced below-average rain and snow during the past six months, causing precipitation deficits of 0 to 4 inches in most areas. Source: High Plains Regional Climate Center

Supplemental Figure 3. Many parts of Arizona and New Mexico have experienced below-average rain and snow during the past 12 months, causing precipitation deficits of 4 to 8 inches in most areas. Southern and eastern New Mexico have been the driest regions, mainly due to very dry conditions during the 2010–2011 winter. Source: High Plains Regional Climate Center

Supplemental Figure 4. Average March precipitation accounts for 8 to 12 percent of the total annual rain and snow in many parts of northern Arizona and New Mexico. The annual percent of March precipitation is generally higher in Arizona than in New Mexico. Source: Western Regional Climate Center

Supplemental Figure 5. Average April precipitation accounts for 8 to 12 percent of the total annual rain and snow in most northern Arizona and New Mexico, while very little rain falls in the southern regions. Source: Western Regional Climate Center

Supplemental Figure 6. Average April precipitation accounts for 8 to 12 percent of the total annual rain and snow in most northern Arizona and New Mexico, while very little rain falls in the southern regions. Source: Western Regional Climate Center

Supplemental Figure 7. After briefly posting negative values, the Arctic Oscillation (AO) flipped back to positive in mid-February. Positive AO values have been associated with the containment of frigid Arctic air in the high latitudes that inhibits cold outbreaks like those experienced in the Southwest in February 2011. Source: NOAA-Climate Prediction Center

Supplemental Figure 8. The amount of water contained in snowpack, or snow water equivalent (SWE), is measured at many snow telemetry sites (SNOTEL) around the West. As of March 2, all but one of the basins in the Upper Colorado and Rio Grande basins in Utah and Colorado were measuring less than 90 percent of average. Source: Natural Resources Conservation Service

Supplemental Figure 9. Early season snowpack deficits in the Upper Colorado River Basin make above-average spring streamflows highly unlikely; October–December precipitation always contributes disproportionately to Colorado River runoff. There is a 50 percent chance that the total April¬–July inflow measured at Lee’s Ferry will be below 67 percent of average and only a 10 percent chance that inflow will exceed 103 percent, according to the March 2 forecast. Source: Natural Resources Conservation Service

Supplemental Figure 10. The seasonal temperature outlook calls for increased chances for warmer-than-average conditions for the March–May period. Source: NOAA-Climate Prediction Center

Supplemental Figure 11. Probabilistic El-Niño Southern Oscillation (ENSO) forecasts suggest a high likelihood the current La Niña will persist through the February–April period, but chances for its continuation precipitously drop thereafter. Source: International Research Institute for Climate and Society

Supplemental Figure 12. Between 60 and 80 percent of the La Niña events during the 1950–2008 period contributed to precipitation totals between 0.4 (10 mm) and 1.2 inches (30 mm) below the March–May average in many parts of Arizona and New Mexico (top panel). Precipitation deficits are greater, between 0.4 (10 mm) and 2.7 (70 mm) inches (bottom panel), when La Niña effects are combined with recent trends (middle panel). The image on the right displays the percent of La Niña events in which the anomalies in the left image occurred. The top, “composite” panel quantifies only the effect of La Niña, while the bottom, “composite + trend” panel includes temperature changes attributed to recent trends as well as La Niña. The year of the La Niña events are indicated at the bottom of the figure. Source: NOAA-Climate Prediction Center

Supplemental Figure 13. Low snowpacks and the expectation of below-average precipitation in coming months feed the below-average spring streamflow forecast in Arizona. The forecast, issued on March 1, calls for the Little Colorado, Verde, Salt, and Gila rivers to be 40, 31, 37, and 27 percent of average, respectively. Source: Natural Resources Conservation Service

Supplemental Figure 14. The Seasonal Drought Outlook calls for drought to persist, intensify, or develop in all of Arizona and New Mexico during the March–May period. This forecast is influenced by expectations for below-average precipitation brought on by La Niña. Source: NOAA-Climate Prediction Center