February 2002 Drought Report

• severe drought affected about 21 percent of the contiguous United States as of the end of February 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 different parts of the U.S. have experienced unusually wet conditions during the last 28 months, little change occurred in the overall 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.

• 2nd driest (out of 108 years) for February 2002,
• 14th driest (out of 107 years) for winter (December 2001-February 2002),
• 28th driest for September 2001-February 2002,
• 33rd driest for March 2001-February 2002.

• the Palmer Indices and Standardized Precipitation Index,
• the runoff 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 February,

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• maps showing the percent of normal precipitation, the departure from normal of the number of days with precipitation, and the longest number of consecutive days with no measurable precipitation, for winter (December-February),

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• maps showing the departure from normal of the number of days with precipitation and the longest number of consecutive days with no measurable precipitation for November-February,
• the percent of average precipitation map for the hydrologic year thus far (October 1, 2001 - March 5, 2002), and the percent of average basin snow water content map for early March, for the SNOTEL stations in the western mountains provided by the USDA Water and Climate Center,
• the mountain snowpack map for the beginning of March, derived from western mountain snow course observations provided by the USDA Water and Climate Center,
• the statewide precipitation ranks for February (short-term) and winter (December-February), September-February, and March-February (longer-term), and

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• the USGS February 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 late February reveal stress on vegetation in parts of the southwestern U.S. The VHI product becomes less useful as vegetation goes dormant during the winter.
• The Keetch-Byram Drought Index (KBDI) is used by the Wildland Fire Assessment System to monitor the risk of wildfires. The late February KBDI showed dry conditions in the southwestern U.S., from Texas to Nevada, and along the southeast and mid-Atlantic coasts. The Forest Service fire danger analysis indicated a high risk of wildfires over the Southwest and from the Carolinas to the eastern Great Lakes states.

• The Pacific Northwest had the 34th driest February on record in 2002.
• But the 33rd wettest winter (December-February) helped the region recover from the extremely dry 2000-2001 season (giving March 2001-February 2002 a rank of 47th wettest).
• Drought emergencies, declared by the state governors, continued in three western states (Washington, Oregon, and Idaho).

With a wet November-December and a dry January-February, this year's rainy season so far (November-February) has averaged near normal for the West region. Highlights:

• 12th driest January-February (see graph to left)
• 33rd driest winter (December-February)
• 48th driest November-February
• 21st driest March-February
• Field observations by ecologists in the eastern Sierra Nevada over the past several months have included unusually high mortality of pinyon pine. For a drought-tolerant species this is indicative of extended severely dry conditions (WRCC).

Impacts from the dryness in this normally dry region include an increasing risk of wildfires and lowering reservoir levels. According to The Arizona Republic, parched lakes and reservoirs are nearing their lowest levels in half a century in some parts of drought-stricken Arizona, and a few have vanished as unusually dry conditions gripped the state for a fourth straight winter.

Some highlights:

• As noted by the Northeast Regional Climate Center, precipitation deficits in some coastal areas of the Northeast ranged as high as 15 inches (381 mm) over the July 2001-February 2002 period (see map to right).
• Many coastal and large urban areas in the Northeast are facing their worst precipitation deficits (July through February) since official climatological record-keeping began more than a century ago (March 1 NRCC report).
• "If the precipitation deficit continues in these areas, then we could be heading into a serious water supply problem," said Keith Eggleston, senior climatologist at the NRCC.

• New Jersey is the drought epicenter in the Northeast. Eight of the last 12 months have been drier to much drier than normal (see graph to right), resulting in the record driest period for seasons back to April-February and a sharp decline in the statewide Palmer Drought Index to levels comparable to the 1960's drought.
• As reported by The New York Times, New Jersey Governor Gov. James E. McGreevey declared a statewide drought emergency in early March.
• The New Jersey State Climatologist noted that the state has experienced record low ground water and river levels, and surface reservoirs on the order of 40% of capacity, half the seasonal norm.
• According to the USGS, record low ground water levels and near-record low streamflow have resulted in historic low flows of the Potomac River.
• The New York Times reported that "forest fires in Maine, usually snuffed by snow, burn to the ground."
• A water emergency has been declared for the 15 eastern Pennsylvania counties along the Delaware River, and the water utility of Stamford, Connecticut, urged residents to reduce consumption by 15 percent (New York Times).
• Drought has been blamed for pine beetle infestations along the Atlantic Coast (New York Times).
• According to an Environmental News Network report, "officials in New Hampshire say that since the drought began late last summer, thousands of dug wells have gone dry. Dug wells are relatively shallow, reaching water 15 or 20 feet below the surface."

• South Carolina is the drought epicenter in the Southeast. Nine of the last 12 months have been drier to much drier than normal (see graph to right), resulting in the record driest period for several seasons from April-February to October-February and a steep intensification of the statewide Palmer Drought Index to levels comparable to the record droughts of the last 100 years (see graph above right).
• According to the Atlanta Journal-Constitution, at mid-February, statewide water restrictions continued across Georgia through the winter, even though that is supposed to be the state's wet season.
• On March 1, a severe drought was declared for Georgia's Flint River Basin (GA Dept. of Natural Resources).
• Georgia soils remained dry, streams and reservoirs were low, and the risk of wildfires was high (GA State Climatology Office).
• The Virginia Drought Monitoring Task Force reported historic low groundwater levels in northern Virginia and the Shenandoah Valley, low streamflows statewide, and low reservoirs (VA State Climatology Office).

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 - 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.