Seasonal Drought Outlook Update

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Seasonal Drought Outlook Update

• Status, Progress, and Improvements
• Douglas Le Comte
• NOAA/CPC
• Drought Forum
• October 20-21, 2005

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Latest Outlook
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Main Inputs to the Outlook
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Drought Outlook History

• Originated with the August 1999 White House
  briefing
• Intent is to present a simple national picture of
  where droughts will improve, persist, or develop
• First released to the public in March 2000
• Issued continuously each month, with updates as
  required, by any of 3 CPC forecasters
• Incorporates numerous inputs, but must be
  consistent with the CPC latest official long-lead
  precipitation outlooks

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Selected Forecast Tools
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CPC 2-Wk Soil Moisture Forecast
http//www.cpc.ncep.noaa.gov/soilmst/cas.shtml
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GSM 13-Week Soil Moisture Forecasts
http//ecpc.ucsd.edu/m2s/m2s_ECPC_forecasts.html
13-week forecast change in soil moisture from the
ECPC GSM model
Jan 7-14
Oct 15-22
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Constructed Analog Soil Moisture NA
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Constructed Analog Soil Moisture USA
http//www.cpc.ncep.noaa.gov/soilmst/cas.shtml
Forecast
Observed
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CDC Klaus Wolter Forecast
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NCDC Drought Amelioration Probabilities
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How Are We Doing?
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Sample Drought Verification Panel
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Retrospective Look at the Forecast Tools
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Time Series of Verification Scores
Mean Pct Correct 59 Mean Persistence Score 45
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How Did We Do With the Western Drought?
Too cautious in September!
Finally got it right in Dec!
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Selected Future Improvements

• Better seasonal temp/precip forecasts thanks to
  new consolidation tool
• Better seasonal soil moisture forecasts from
  NLDAS projects (Univ. of WA, Princeton, NCEP)
• Research leading to improved understanding of the
  underlying causes of drought (e.g., air-sea and
  ground-air interactions)

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Parting Wisdom

• If youre going to predict, predict often. As
  long as you keep updating your prediction,
  people forget your last prediction.
• Milton Friedman