• severe drought affected about 21 percent of the contiguous United States as of the end of April 2002;
• the coverage of the current (November 1999-present) drought peaked in August 2000 at about 36% of the contiguous U.S., which was as extensive as the major droughts of the last 40 years, but not as large as the "dust bowl" droughts of the 1930's and 1950's;
• the total drought area decreased to about 10 percent by November 2000, but has shown a general increasing trend for much of the period since then (see graph below left);
• on a broad scale, the last two decades were characterized by unusual wetness with short periods of extensive droughts, whereas the 1930's and 1950's were characterized by prolonged periods of extensive droughts with little wetness (see graph below right);
• although various parts of the U.S. have experienced unusually wet conditions during the last 30 months, little change occurred in the aggregate national wetness picture during much of this period;
• the percentage of the nation severely wet has held steady at about three to eleven percent during this period, only recently falling below one percent (see graph below left);
• a file containing the national monthly percent area severely dry and wet from 1900 to present is available;
• historical temperature, precipitation, and Palmer drought data from 1895 to present for climate divisions, states, and regions in the contiguous U.S. are available at the Climate Division: Temperature-Precipitation-Drought Data page in files having names that start with "drd964x" and ending with "txt" (without the quotes).

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 and the departure from normal of the number of days with precipitation for April, and the maximum number of consecutive days with no measurable precipitation for November-April,

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• the percent of average precipitation map for the hydrologic year thus far (October 1, 2001 - May 3, 2002), and the percent of average basin snow water content map for early May, for the SNOTEL stations in the western mountains provided by the USDA Water and Climate Center,
• the mountain snowpack map for the beginning of May, derived from western mountain snow course observations provided by the USDA Water and Climate Center,
• the statewide precipitation ranks for April (short-term) and February-April, November-April, and May-April (longer-term), and

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• the USGS April 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 May reveal stress on vegetation in parts of the Plains, in the southwestern U.S., and parts of the central Rockies.
• The Keetch-Byram Drought Index (KBDI) is used by the Wildland Fire Assessment System to monitor the risk of wildfires. The early May KBDI showed dry conditions in the Desert Southwest, along the Rio Grande Valley, parts of the southern and northern Plains, and across Florida to the mid-Atlantic coast. The Forest Service fire danger analysis indicated a high risk of wildfires in the Southwest, across Montana to the adjoining sections of the Dakotas, and in the Upper Mississippi Valley. The fire threat conditions can change rapidly from week to week.

The rainy season (October-April) for the West region started out wet, but the last four months have been drier than normal regionwide (see top right graph below). January-April 2002 ranked as the ninth driest January-April on record for the region (see bottom right graph below). The last 12 months ranked as the 17th driest May-April on record for the region.

• Parts of North Central Montana experienced record drought during 2002
• Colorado had the driest October-April through March-April on record in 2002
• Arizona had the driest September-April on record in 2002
• According to the USDA, as of the beginning of May, the following ten states (all but 2 in the West) had 25% or more of their range and pasture lands in poor to very poor condition:

  NM - 83%, CO - 68%, AZ - 64%, MT - 54%, WY - 42%, TX - 39%, KS - 37%, UT - 35%, CA - 30%, OR - 27%

• Several years of drought have dried the soil, allowing strong winds to whip up blinding dust storms across several Rocky Mountain and Great Plains states, from Montana to Colorado. A dust storm in western Kansas on April 16 was visible in satellite images.
• According to the U.S. Forest Service, reports have been received of considerable tree mortality in the Great Basin, indicating long-term drought stress.
• According to State Climatologist Jan Curtis, Wyoming reservoirs are low, runoff is down and dust storms are more frequent.
• USDA reports of drought impacts in Arizona include:
  • record low April and January-April streamflow into the reservoir system
  • well below-normal precipitation
  • below-average reservoir storage, with Horseshoe Lake reporting empty
  • reports of cacti dying in some areas
• The Salt Lake Tribune reported concern over water restrictions in Utah due to a fourth consecutive year of drought
• According to local National Weather Service reports, some cities in New Mexico are running dangerously low on water supplies
• Wildfires became a growing problem during April in Colorado

• National Weather Service reports for deep south Texas:
  • The extended drought has dropped lake levels so low that the city of Zapata has been forced to take emergency measures to ensure an adequate water supply.
  • Blowing dust was becoming a problem locally in the Rio Grande Valley.
  • The dryness has been accompanied by excessive heat for this time of year. The Weather Service reported that, from January 1st thru May 7th 2002, the Brownsville office had 24 days with highs in the 90s, 17 of which have been consecutive. This breaks the old record of 20 total days in the 90s from January 1st through May 7th, 1982.
• El Paso, Texas had no measuraable precipitation during April. The dry run extended into early May, with May 6 marking the 90th consecutive day with no precipitation, setting a new all time record for consecutive days without measurable precipitation.
• A dust storm in western Kansas on April 16 was visible in satellite images.

• In spite of the recent rains, long-term deficits gave New Jersey a rank of driest July-April on record
• The recent rains were not enough to offset the long-term deficits in Maryland, where October 2001-April 2002 ranked as the driest such period on record
• In 2002, South Carolina had the driest Palmer Hydrological Drought Index since the 1950s
• Drought declarations remained in effect for many Northeast counties
• During April, Rhode Island became the latest Northeast state to enter a drought watch.
• According to news reports, most states in the Northeast have banned some uses of water and imposed rationing on others
• At the end of April, Maryland well measurements indicated groundwater was still below average in many areas.
• The recent rains have helped recharge the reservoir storage supplies of the Delaware River Basin watershed, but aggregate reservoir levels are still well below median and remain in drought categories. The 13,539 square-mile watershed drains portions of New York State, Pennsylvania, New Jersey, and Delaware.

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.