El Paso County Cooperative Extension Meeting

Nolan J. Doesken, Nolan J. Doesken, State ClimatologistState Climatologist

Colorado Climate CenterColorado Climate CenterPresented to El Paso County Ranchers, August 31, 2006.

Prepared by Odie Bliss

Where Have We Been?

U.S. Drought Monitor for July 12006 2005 2004

2003 2002 2001

48-month SPI graph

Fraction of Colorado in Drought Based on 48 month SPI

(1890 - June 2006)

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Colorado Springs Water Year Precipitation*

* Colorado Climate Center adjusted for station changes.

Colorado Springs Water Year Precipitation (Adjusted Values*)from 1893-2006

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Summary

• After generous moisture in 1980s and 1990s, drier than average conditions have been dominant since fall 1999.

• Above average temperatures have also prevailed since the mid 1990s.

• Recent drought episode has been severe (with respect to recent history) with some similarities to the droughts of the 1930s, 50s and 70s.

Where Are We Now?

From http://home.fuse.net/Wyght/WestHP2000c.html

NWS National Precipitation Analysis for Past 60 days

http://www.srh.noaa.gov/rfcshare/precip_analysis_new.php

Colorado Springs Accumulated Deficit

Colorado Springs Accumulated Precipitation Deficit

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Colorado Monthly PrecipitationColorado Springs Monthly Precipitation vs. Average Precipitation

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Precip 1971-2000 average

El Paso County Average Precipitation

El Paso County Average Precipitation, 1971-2000

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Colo Spr Rush Karval Pueblo Monument Ruxton Park

El Paso County PrecipitationEl Paso County Precipitation

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Colo Spr Rush Karval

Pueblo Monument Ruxton Park

Summary of Current Conditions

• Rainfall has been spotty, but generally above average in El Paso County and most of southern and Central Colorado since early July.

• Summer rains have been sufficient to bring substantial short-term drought relief to this area.

What Comes Next?

Pacific Sea Surface Temperature Projections

http://www.cdc.noaa.gov/people/klaus.wolter/SWcasts/

Multivariate ENSO Forecast

Last updated 4 August 2006

http://www.cdc.noaa.gov/people/klaus.wolter/MEI/

CPC Sep-Nov 06 Forecast

http://www.cpc.noaa.gov/products/predictions/30day/

Temperature Precipitation

CPC Dec 06-Feb 07 Forecast

http://www.cpc.noaa.gov/products/predictions/30day/

Temperature Precipitation

CPC Mar-May 07 Forecast

http://www.cpc.noaa.gov/products/predictions/30day/

Temperature Precipitation

CPC Jun-Aug 07 Forecast

http://www.cpc.noaa.gov/products/predictions/30day/

Temperature Precipitation

Summary of Forecast Information

• Weak La Nina of recent months has given way to weak El Nino − probably a positive sign

• Very dry winters (like last winter) are more likely to be followed by a wetter winter

• Prediction of next spring and summer very "Iffy"• Long range prediction for this area will almost

always be "Iffy"• Best to be thankful for recent rains, but anticipate

more dry weather ahead

Volunteers Wanted To Help Measure El Paso County Precipitation!

Join CoCoRaHS or RainCheck!

http://www.rain-check.org/index.html

http://www.cocorahs.org

For More Information, Visit the CoCoRaHS Web Site

Support for this project provided by Informal Science Education Program,National Science Foundationandmany local charter sponsors.

http://www.cocorahs.org

Colorado Climate CenterColorado State University

• Data and Power Point Presentations available for downloading

• http://ccc.atmos.colostate.edu

click on “Drought”

then click on “Presentations”