North American Drought Briefing: Monitoring

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North American Drought BriefingMonitoring
Forecasts

• Climate Prediction Center/NCEP/NOAA
• April 9, 2008
• http//www.cpc.ncep.noaa.gov/products/Drought

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Partners Contributors

• CPC Kingtse Mo, Wanru Wu, Muthuvel Chelliah,
  Wesley Ebisuzaki, Yun Fan, Huug van den Dool, Wei
  Shi
• EMC NLDAS Team Ken Mitchell, Youlong Xia, Jesse
  Meng, Helin Wei
• EMC NAEFS Team Zoltan Toth, Yuejian Zhu
• NASA/GSFC Brian Cosgrove, Chuck Alonge, Randy
  Koster
• Princeton Univ. Eric Wood, Lifeng Luo, Justin
  Scheffield
• Univ. of Washington Andy Wood, Dennis
  Lettenmaier
• Web Masters Viviane Silva, Joe Harrison
• Project Funded by NOAA CPO/CPPA NASA

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Summary

• The Southeast drought continues, but shows sign
  of improvement
• Drought persists for the region extending from
  western Texas northward to the Dakotas
• Drought condition improves over the western
  United States except the California-Arizona
  border.
• Situation is getting worse over the Dakotas.

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SE still dry
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Weekly P in March
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Monthly P anomaly for JFM
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SPI

• Dry conditions over the Southeast shows
  improvement
• Dryness over the Dakotas and Minnesota persists
• Western Texas is still dry
• Wetness over Arkansas, MO, KY to the Northeast

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Streamflow from USGS
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SM (March-Feb 2008)
The increase of SM reflects of the P anomalies
for March
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Soil Moisture Percentile for mar 2008
(a) NARR
b) Multi-model ensemble SM percentile from the
University of Washington
D4 D3 D2 D1 Drought D0 lt 20
D4 D3 D2 D1
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SM percentileNASA/GSFC

• Common features for all SM maps
• Southeast shows some improvement in the recent
  season, but it is still very dry
• Wetness covers the region extending from the Gulf
  states to the central U.S. to Northeast
• Dryness extends from western Texas northward to
  the Dakotas.
• Southern California is dry

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Drought over the Southeast
Long lasting drought Jan 2006-Aug 2006
SPI6lt-0.8 A short period from Aug-Dec 2006, SPI6
came out of drought, but Drought returned from
Jan 2007 and continues until now.
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Snow Water Equivalent Snow Depth
National Snow Analyses http//www.nohrsc.nws.gov
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Weekly mean SSTA 2-9 Apr 2008
Cold ENSO shows a sign of weakening But forecasts
still call for weak cold ENSO continues through
summer
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GFS week1 and week2 fcstIC 06Apr 2008
P fcst
SM downscaled from the MFS fcst based on the
Leaky Bucket model
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U WashingtonFcst for JFM 2008Good Fcst
SM Fcst for JFM 2008
Runoff Fcst for JFM 2008
Verification Multi model SM
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U Washington SM FcstESP based on ENSOIC 4
April 2008
1 month lead
The Southwest drought will improve!!! Western
Texas, New Mexico dry
2 month lead
3 month lead
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Princeton U Fcst made in Jan IC 200712 CFS
downscaling SM based on VIC
Mar
Jan
Feb
Verification
Feb
From Princeton University Lifeng Luo IC
200712 CFS downscaling total SM
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Princeton CFS Downscaling Forecasts SM
Percentile
Initialized 200803
April
(a) Mar2008
http//hydrology.princeton.edu/luo/research/FOREC
AST/fcstvrf.php
May
Jun
20
Ca_Sm fcst IC6 April 2008
Fcst for May
Fcst for the end of July 2008
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Summary

• The long-lasting drought over SE continues. All
  forecasts suggest some relieve in the next
  season.
• Western Texas and Dakotas were dry and is likely
  to be dry due to the cold ENSO condition.
• Wetness over the central United States for the
  next 2 weeks.