Climate of 2005 - August
U.S. Regional Drought Watch

Regional Overview

Some regional highlights:

• One state had the tenth driest, or drier, August in the 111-year record:
  • Oregon: 6th driest
• Two states had the tenth driest, or drier, July-August:
  • Idaho: 5th driest
  • Montana: 10th driest
• Illinois ranked tenth driest, or drier, for several seasons:
  • May-Aug: 8th driest
  • Apr-Aug: 8th driest
  • Mar-Aug: 6th driest
  • Feb-Aug: 7th driest
• Arkansas ranked tenth driest, or drier, for several seasons:
  • Apr-Aug: 10th driest
  • Mar-Aug: 7th driest
  • Feb-Aug: 7th driest
• As noted in media reports (The New York Times, 8/15; WKYT27 Lexington, KY, 8/12), the Midwest drought has lowered water levels along parts of the Mississippi and Ohio Rivers, curtailing barge traffic which affected several economic activities. The drought has also dried up wells, caused insect infestations and wreaked havoc on corn and soybean fields.
• During the last two months, drought declarations or emergencies have been declared in four states: Wisconsin (Wisconsin Ag Connection, 7/18), Illinois (Brownfield Network, 7/27), Missouri (Kansas City Star, 8/25), and Arkansas (AP, 8/23).
• By the end of the month, 60% or more of the pasture and range land was in poor to very poor condition in Missouri (61%), Arkansas (68%), Pennsylvania (66%), Connecticut (72%), and Rhode Island (95%).
• End-of-month and month-averaged soil moisture conditions were drier than normal across a broad swath from the southern Plains to the western Great Lakes, and parts of the Pacific Northwest, northern and central Rockies, Ohio Valley, and Northeast, based on model computations (CPC-1, CPC-2, MRCC). The models also indicated dry soil moisture conditions in parts of Alaska and Hawaii, and near the surface and at depth from Iowa to the Great Lakes.
• According to end-of-August USDA observations, more than 50 percent of the topsoil moisture was rated short to very short (dry to very dry) across the Pacific Northwest and northern Rocky Mountain states, and in a swath from the southern Great Plains to the Great Lakes and Northeast states. This is drier than the 5-year and 10-year averages across much of the area.
• Streamflow levels were below seasonal norms across parts of the Pacific Northwest, northern and central Rockies, central Plains, Great Lakes, Mississippi valley, and Northeast to mid-Atlantic states, as computed by models and based on USGS observations.

These overall conditions are evident in the following indicators:

• Palmer Drought Indices,
• Standardized Precipitation Index,
• long-term (36 to 60 month) percent of normal precipitation maps,
• airport station percent of normal precipitation maps,
• statewide precipitation rank maps,
• Cooperative station percent of normal precipitation maps,
• percent of average maps for the SNOTEL stations in the western mountains provided by the Western Regional Climate Center
  • hydrologic year precipitation,
• satellite-based observations of vegetative health,
• National Weather Service model calculations of
  • soil moisture,
  • runoff,
  • evaporation,
• National Weather Service model calculations of soil moisture using the Leaky Bucket Model,
• Midwest Regional Climate Center model calculations of soil moisture,
• topsoil moisture conditions observed by the USDA and mapped by the Climate Prediction Center,
• pasture and range land conditions observed by the USDA and mapped by the Climate Prediction Center,
• streamflow maps maintained by the USGS.

A detailed review of drought and moisture conditions is available for all contiguous U.S. states and the nine climatological regions:

REGIONS:

• Several large wildfires burned across the West during the month. By the end of August, most of the fires were concentrated in the northern Rockies, although during the month numerous large fires had burned parts of Alaska and the Columbia Plateau regions.
• Reservoir levels in the West reflected the long-term precipitation deficits in many states. The percent area of the western U.S. (Rockies westward) experiencing moderate to extreme drought (as defined by the Palmer Drought Index) increased to about 20% in August, reflecting continued dryness in the Pacific Northwest (June, July, August).

Additional Contacts:

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.

• For all climate questions other than questions concerning this report, please contact the National Climatic Data Center's Climate Services Division:
  Climate Services Division
  NOAA/National Climatic Data Center
  151 Patton Avenue
  Asheville, NC 28801-5001
  fax: 828-271-4876
  phone: 828-271-4800
  email: ncdc.info@noaa.gov
  
  
  
• For further information on the historical climate perspective presented in this report, contact:
  Richard Heim
  NOAA/National Climatic Data Center
  151 Patton Avenue
  Asheville, NC 28801-5001
  fax: 828-271-4328
  email: Richard.Heim@noaa.gov
  
  
  -or-
  
  
  Jay Lawrimore
  NOAA/National Climatic Data Center
  151 Patton Avenue
  Asheville, NC 28801-5001
  fax: 828-271-4328
  email: Jay.Lawrimore@noaa.gov