These overall conditions are evident in the following indicators:

• the Palmer Indices and Standardized Precipitation Index,

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• the runoff, evaporation, and soil moisture conditions as calculated by the National Weather Service,
• maps showing the percent of normal precipitation for airport stations for August and summer (June-August),

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• the percent of average precipitation map for the hydrologic year thus far (October 1, 2001 - August 31, 2002) for the SNOTEL stations in the western mountains provided by the USDA Water and Climate Center,
• the statewide precipitation ranks for August (short-term) and summer (June-August), March-August, and September-August (longer-term), and

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• the short-term surface wetness anomaly maps for August computed by the National Climatic Data Center from the Special Sensor Microwave Imager (SSMI), a polar orbiting satellite with global coverage, and

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• the USGS August daily streamflow maps.

Two other drought-related monitoring tools are the Vegetation Health Index and the Keetch-Byram Drought Index:

• NOAA satellite observations of vegetation health from early September revealed stress on vegetation from the southwestern U.S. into the central Plains, and across parts of the Midwest to Great Lakes.
• The USDA Forest Service uses a satellite-based vegetation health index tool to monitor the risk of wildfires. This Greenness Index for late August revealed above-average stress on vegetation across much of the West and adjoining Great Plains, as well as parts of the eastern U.S. and Ohio Valley.
• The Keetch-Byram Drought Index (KBDI) is used by the Wildland Fire Assessment System to monitor the risk of wildfires. The end-of-August KBDI showed dry conditions across parts of the West, central and southern Plains, Ohio Valley, and much of the eastern U.S. The Forest Service fire danger analysis indicated a high risk of wildfires across parts of the western U.S. into the central Plains, and across part of Maine. The fire threat conditions can change rapidly from week to week.

The rainfall and surface wetness patterns averaged across the summer months (June-August) clearly indicate the areas suffering from moisture stress during this season. The greatest wetness deficiency occurred in the central Plains and Southeast states, with deficiencies developing in the Ohio Valley (see map to right). Below-normal rainfall occurred at stations in those areas as well as along most of the east coast and much of the Far West, Puerto Rico, and the Hawaiian Islands (see map below left). States having summer precipitation ranks of tenth driest, or drier, were located in the southwestern U.S. and Ohio Valley (see map below right).

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By the beginning of September, topsoil moisture conditions were extremely dry across much of the western U.S. According to September 1 USDA reports, 70% or more of the topsoil was short to very short in Wyoming (91%), Utah (90%), Oregon (89%), New Mexico (85%), and Idaho (71%).

Range and pasture conditions continued to deteriorate in many areas during August. According to September 1 USDA reports, conditions on 49% of the nation's pastures and rangeland were poor or very poor (compared to 37% at this time last year):

• 80% or more of the range and pasture lands were reported in poor to very poor condition in Colorado (93%), California (90%), Arizona (83%), and Wyoming (80%),
• 50% or more poor to very poor in Utah (73%), New Mexico (70%), Oregon (63%), Washington (51%), and Nevada (50%).

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

• Pacific Northwest region
• West region
• Southwest region
• Arizona
• California
• Colorado
• Nevada
• New Mexico
• Oregon
• Utah
• Wyoming

Meanwhile, August marked the third consecutive dry month for much of the Ohio Valley, resulting in the 18th driest summer for the Central region. August was rainy over parts of the South region, except for the drought areas of the Trans Pecos and deep south Texas, which continued very dry.

By the beginning of September, topsoil moisture conditions were extremely dry across much of the central U.S. According to September 1 USDA reports:

• 70% or more of the topsoil was short to very short in Ohio (84%), West Virginia (79%), Kansas (73%), Nebraska (71%), Illinois (71%), and Kentucky (71%), and
• 50% or more short to very short in Missouri (65%).

Range and pasture conditions continued to deteriorate in many areas during August. According to September 1 USDA reports:

• 80% or more of the range and pasture lands were reported in poor to very poor condition in Nebraska (86%),
• 75% or more poor to very poor in Kansas (73%), and
• 50% or more poor to very poor in Ohio (68%), Indiana (67%), South Dakota (60%), North Dakota (56%), Montana (54%), and Missouri (51%).

• West North Central region
• Central region
• Illinois
• Missouri
• Nebraska
• Ohio
• West Virginia

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

• Southeast region
• Georgia
• North Carolina
• South Carolina
• Virginia
• Northeast region
• Delaware
• Maine
• Maryland
• New Jersey

Colorado - Delaware - Delaware River Basin (DE-NJ-NY-PA) - Florida Panhandle - Georgia - Hawaii - Idaho - Kentucky - Maine - Maryland - Missouri - Montana-1 - Montana-2 - Nebraska - New Jersey-1 - New Jersey-2 - New Jersey-3 - New Mexico - North Carolina - Oklahoma-1 - Oklahoma-2 - Oklahoma-3 - Oregon-1 - Oregon-2 - Pennsylvania-1 - Pennsylvania-2 - Pennsylvania-3 - South Carolina - Texas - Vermont - Virginia - Washington - Wyoming

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

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