January 9, 2002

 Klamath Basin Update - January 2002

Special Report: Recent Rainfall Ends Drought

Summary

Precipitation across the Klamath Basin, as well as most of Northern California and the states of Oregon and Washington, was well below normal during the 2000-2001 "rainy season" (October-June).  This drought followed several years of below-normal precipitation for the area.  However, precipitation from mid-November 2001 to early January 2002 has been frequent and widespread, providing moisture for re-establishing pastures and rangeland, and improving winter grain prospects.  This moisture is also recharging aquifers and reservoirs. 

Imagery

A NOAA 16 satellite image from November 9, 2001 clearly identifies the Klamath Basin Hydrologic Districts, outlined in yellow. 

Recent Weather

Palmer Long Term drought maps from September 22, 2001, and January 5, 2002, illustrate the turnaround from severe-to-extreme drought that covered the Far-Western U.S. during Summer and Autumn 2001.  The Klamath Basin area is designated by NOAA's Climate Prediction Center as being "Very Moist" as of January 5, 2002.  A National 7-Day Cumulative Precipitation Map through January 5, 2002 indicates that the Klamath Basin and all of southwest Oregon and Northern California received "moderate to heavy" precipitation during that week.

Graphs of  precipitation from October 1 - December 31, 2001 for two weather stations, Mt. Shasta, California, and Medford, Oregon, are provided by NOAA's Climate Prediction Center.  Note that precipitation was below normal from October through mid-November for these stations, then heavy and frequent precipitation amounts have resulted in precipitation levels well above normal by the end of the year. 

Precipitation graphs created from U.S. Air Force Gridded Weather Data illustrate rainfall from October 1 through September 30 and compare a period from October 1, 1999 through January 5, 2002.  These graphs include all the Air Force data for Modoc County and Siskiyou County, California, and Klamath County, Oregon.  Note that for each county, this year precipitation began around November 15, 2001 and last year got off to a meager start only after February, and in 1999/2000 rainfall did get a "good start" until January.

This region, along with the other agricultural areas of the United States,. is continually monitored by PECAD and will be reported on regularly.

For more information, contact Carl Gernazio of the Production Estimates and Crop Assessment Division 
at 202-690-0136 or by e-mail at gernazio@fas.usda.gov.