Exploitation of Ensemble Output at NCEP HPC

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Exploitation of Ensemble Outputat NCEP HPC
Peter C. Manousos NCEP HPC Science Operations
Officer (peter.manousos_at_noaa.gov)
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Goals of Presentation

• Show how ensemble output is exploited at HPC
• Answer questions

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WFOs

• NWS CONSTRUCT
• OF OPERATIONAL
• OFFICES
• CWSUs and Regional Headquarters not depicted

RFCs
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HPC PRODUCTS AND SERVICES
http//www.hpc.ncep.noaa.gov

• QPF
• 5 Day QPF
• Excessive Rainfall
• Probabilistic Snow/Ice
• Compile National Flood Outlook
• Fronts/pressures
• Surface Analysis Daily Wx Map
• 12h - Day 7 Forecasts
• General Weather through 48h
• Day 3-7 Max/Min/24h PoP (gridded)
• Tropical guidance (to Day 7)
• Model diagnostics
• International Desk
• Experimental products

• HPC also provides Emergency Special Products
  and Services

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Ensemble Exploitation
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Static Reference

• Nominally derived ensemble parameters (means,
  spreads, clusters, etc.)
• Serve as reference to quantify pattern evolution
  uncertainty and assist in pattern evolution
  preference

http//www.hpc.ncep.noaa.gov/mdd
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http//www.hpc.ncep.noaa.gov/wwd
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Automated Guidance
http//www.hpc.ncep.noaa.gov/wwd/impactgraphics

• Automated ensemble products highlighting areas
  most likely to exceed critical thresholds

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Starting Point

• Forecaster selected blends to generate
  starting point grids

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Targeted PDF Application

• Generation of probabilities by applying
  (centering) ensemble spread on manually generated
  deterministic forecast

http//www.hpc.ncep.noaa.gov/ (winter weather,
QPF, Medium Range)
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QPF Confidence Interval

• Max/Min QPF derived from HPC QPF
• and
• Characteristic
• uncertainty of
• current pattern

http//www.hpc.ncep.noaa.gov/qpfci/qpfci.shtml
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Questions ???
peter.manousos_at_noaa.gov 301 763 8000 x 7307
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Downscaling to 5km
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• 5km PRISM data is applied to 380 point
  forecasts to generate 5km forecast grid

5km Gridded MOS is being tested to replace
PRISM data
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NDFD D5 Max T HPC
http//www.hpc.ncep.noaa.gov/5km_grids/5km_gridsbo
dy.html
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QPF related grids can be downscaled via PRISM as
well
Impact of downscaling on QPF related grids only
occurs where significant gradients in terrain
exist
http//www.hpc.ncep.noaa.gov/wwd/internal