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

Regional Overview

For the Pacific Northwest as a whole, June was the fourth near to wetter-than-normal month following a dry winter, although parts of the region were drier than normal this month.

The June precipitation pattern at the primary stations in Alaska was mixed but mostly drier than average along the coast and wetter than average at the interior stations. Across Hawaii, most of the stations were drier than average. In Puerto Rico, the precipitation signal was mixed, based on National Weather Service radar estimates of precipitation. June streamflow averaged near normal for Puerto Rico and the Hawaiian Islands.

Long-term moisture deficits persisted in many areas. Six-month dryness was evident for parts of the Northwest, northern Rockies, southern Plains, Mississippi to Ohio valleys, Great Lakes, and mid-Atlantic states. The Pacific Northwest has experienced a dry winter followed by a wet spring, although spring excesses did not significantly ease six to seven years of precipitation deficits.

The southwestern U.S. has been very wet during the winter and spring, although long-term deficits remained across parts of the Southwest and West, and much of the central to northern Plains. This is reflected in the end of June to beginning of July U.S. Drought Monitor maps. The Southwest has recovered at the 12 to 24 month timescales, but still shows dryness in some parts at the 36 to 60 month timescales.

Some regional highlights:

• Three states had the tenth driest, or drier, June in the 111-year record.
• Four states had the tenth driest, or drier, April-June on record.
• Illinois had the second driest March-June on record. By the end of June, the Farm Service Agency (FSA) executive directors of 47 counties in Illinois had filed drought reports, which is the first step to initiate a government disaster declaration (Illinois Farm Bureau, July 1, 2005).
• As noted by the National Weather Service, by the end of the month the state of Texas had 78 counties with burn bans, or approximately one-third of all counties statewide.
• End-of-month and month-averaged soil moisture conditions were drier than normal across parts of the southern Plains, Pacific Northwest, and mid-Atlantic states, and much of the Great Lakes to Mississippi and Ohio valleys, based on model computations (CPC-1, CPC-2, MRCC). The models also indicated dry soil moisture conditions in eastern Alaska and near the surface and at depth across the Great Lakes to Ohio Valley.
• According to end-of-June USDA observations, more than 50 percent of the topsoil moisture was rated short to very short (dry to very dry) in several states from the southern Plains to the Mississippi Valley, and eastward to the mid-Atlantic coast. 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 Rockies, southern Plains, Great Lakes, Mississippi and Ohio valleys, and mid-Atlantic states, both as computed by models and based on USGS observations.
• Several large wildfires were burning by the end of the month in central Alaska and the U.S. Southwest. The Alaska fires were burning in areas that experienced severe dryness last summer and are on the edge of the area with current dry soil moisture conditions. The unusually heavy precipitation during late fall to spring in the Southwest resulted in rapid and extensive undergrowth which provides abundant fuel for fires.

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,
• 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,
• 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,
• 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:

• The precipitation pattern for the West during late autumn to winter (November-February) consisted of unusually wet conditions in the Southwest and very dry conditions in the Northwest. The spring to early summer months (March-June) have seen near to wetter than average conditions across much of the West. In spite of the recent precipitation, the hydrologic year to date (October-June) precipitation pattern still consists of a sharp north-south gradient in moisture receipt.
• 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) decreased from about 67% in July 2004 to under 10% by October. Intensification of drought in the Pacific Northwest (Nov., Dec., Jan., Feb., Mar., Apr.) resulted in an expansion of the western drought area to about 28% by the end of February. Above-normal precipitation from storms during the last several months in the Pacific Northwest brought the western area coverage down to near 11% by the end of June.

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