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In spite of the November-December wetness, long-term moisture deficits (last 6 to 24 to 60 months) persisted across most of the West. Much of the Great Plains has suffered from moisture deficits in the 6-month time frame, while parts of the Plains and Upper Midwest have had significant moisture deficits back 12 to 24 months. In the central Plains, significant deficits even show up at 60 months.

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Some regional highlights:

• Recent winter storms have brought an average to above-average snowpack and water year-to-date precipitation to much of the West. The above-average snowfall is evident in many reports from both valley stations and high altitude SNOTEL stations. However, due to the effects of the long-term drought, soil moisture conditions remained dry in many areas and the reservoirs in most of the western states were still low or depleted. Even though the water content of the mountain snowpack was near or above end-of-December norms, this is early in the snow season and snow water content was well below April seasonal peak norms. As noted in the January 6 U.S. Drought Monitor discussion, the farther into the season that surplus snowpack water continues, the greater the possibility that significant increases in reservoir storage could be experienced this spring.
• The percent area of the western U.S. (Rockies westward) experiencing moderate to extreme drought (as defined by the Palmer Drought Index) decreased during December to about 56%. While this is not near record historical levels, it is still comparable to the major droughts of the 20th Century.
• The area from western Texas to eastern New Mexico has experienced severe short-term dryness recently. This is apparent in December and October-December percent of normal precipitation maps. Blowing sand and dust were detectable via satellite (SSEC) in mid-December. The dryness has been especially severe during the last 6 months.
  • Plots of the Standardized Precipitation Index (SPI) for the Texas High Plains and the New Mexico southeast and northeast Plains indicate that the most severe dryness occurred in the 6- to 12-month time frames. Historical plots of the 6-month SPI (southeast NM, northeast NM, northwest TX) and Palmer Hydrological Drought Index (southeast NM) indicate that the recent dryness is comparable to the worst drought episodes of the 20th Century.

• Palmer Drought Indices,
• Standardized Precipitation Index,
• airport station percent of normal precipitation maps,
• statewide precipitation rank maps,
• Cooperative station percent of normal precipitation maps,
• satellite-based observations of surface moisture,
• National Weather Service model calculations of
  • soil moisture,
  • runoff,
  • evaporation,
• Midwest Regional Climate Center model calculations of soil moisture,
• percent of average maps for the SNOTEL stations in the western mountains provided by the Western Regional Climate Center
  • hydrologic year precipitation,
  • snow water equivalent of snowpack,
• snow course snowpack observations in the western mountains provided by the USDA NRCS
• streamflow maps maintained by the USGS.

A detailed review of drought conditions is available for the following regions and states:

• Southwest region
• Arizona
• Colorado
• Idaho
• Montana
• Nevada
• New Mexico
• Oregon
• Utah
• Wyoming

• West North Central region
• East North Central region
• South region
• Arkansas
• Iowa
• Kansas
• Louisiana
• Minnesota
• Mississippi
• Nebraska
• North Dakota
• Oklahoma
• South Dakota
• Texas

• Georgia
• South Carolina

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For additional information on current and past wildfire seasons please see the National Interagency Fire Center web site or the U.S. Forest Service Fire and Aviation web site.

NCDC's Drought Recovery Page shows the precipitation required to end or ameliorate droughts and the probability of receiving the required precipitation.

Additional climate monitoring graphics can be found at the Climate Prediction Center's monitoring pages:

• Weekly, Monthly, 3-Month, 12-Month Monitoring
• El Nino, Drought, Snow Cover, and Degree Day Monitoring
• Weekly Drought Monitoring
• Soil Moisture Monitoring

Precipitation and modeled soil moisture anomaly maps for the Midwest U.S. can be found at the Midwest Regional Climate Center's monitoring page.

Drought conditions on the Canadian prairies can be found at the Agriculture and Agri-Food Canada Drought Watch page.