U.S. - Canada Bilateral

North American Ensemble Forecast System

Dr. Louis W. UccelliniNational Weather Service

November 6-7, 2008

Outline

• History of NAEFS• Current Status• How NAEFS is Used

– Medium Range– Severe Weather– Winter Weather

• Ongoing development– Possible FNMOC participation

• Ongoing Discussion– Possible expansion to day 35– Increased resolution

• Issue– Data Flow

History of NAEFS

• Feb 2003 - NOAA / MSC high level agreement • May 2003 – 1st NAEFS Workshop• Sept 2004 - Initial Operational Capability

implemented at MSC & NWS• Nov 2004 - Inauguration ceremony & 2nd NAEFS

Workshop (Canada, Mexico, U.S.)• May-Sept 2006 – Operational implementation: bias

correction, climate anomalies, (Canada, U.S.)• Dec 2007 – downscaling (U.S.)• 2008 – Ongoing implementations and improvements

(4th Workshop with Canada, Mexico, U.S, Oct 6-8)• 2007-08 – NAEFS Training developed for international

regions (South America, Central America, Caribbean, Africa

• NAEFS basic product list – Ensemble mean, spread, probabilities, etc.– 76 variables (by Dec’08)

• U,v,t,z,CAPE, precip type, etc.

– 7 domains (produced for GEFS, for NAEFS during FY09)• Global, NH, NA, CONUS, SA, Caribbean, Africa

• Over 600 products requested by users– Graphics

• NAWIPS (NAEFS, GEFS, CMC)• NCEP Model Web Page – operational Sept 07 (GEFS only, NAEFS coming)• EMC web page - http://www.emc.ncep.noaa.gov/gmb/ens/NAEFS/NAEFS-prods.html

(NAEFS, GEFS, CMC) CONUS• Canada Web site: http://www.meteo.gc.ca/ensemble/index_naefs_e.html

– Grids (NAEFS, GEFS, CMC)• NAWIPS• ftp site (GRIB2) (external access)

ftp://ftpprd.ncep.noaa.gov/pub/data/nccf/com/gens/prod/naefs.YYYYMMDD/cc • NDGD (2m temps, 10m wind, sfcp on 5x5km grid (based on RTMA)) - available on above

ftp site as well• NOMADS – NAEFS to become part of NOMADS by December 2008

North American Ensemble Forecast System

Canada contributes 42 runs/day to 16 days at 1 deg resolution US contributes 84/day to 16 days at ~90 km (T126) resolution

How NAEFS is Used

• Medium Range – Day 1-7 (CONUS, AK)– Assess Uncertainty– Depict alternate scenarios– Ensemble mean often better

than individual runs and is increasingly used in forecasts

– Experimental PQPF product • Day 8 -14 temp forecast• Severe Weather – out to Day 8• Winter Weather

– Probabilistic snowfall amounts in medium range North American Ensemble Forecast System

8 to 14 Day Temperature Guidance00z forecast [EXPERIMENTAL]

Valid: November 08 to 14, 2008, Issued: Oct 31, 2008

From Bias correction (NCEP, CMC)Dual-resolution (NCEP only)Down-scaling (NCEP, CMC)Combination of NCEP and CMC

NAEFS final products

NCEP/GEFS raw forecast

8+ days gain

Possible FNMOC Participation(Fleet Numerical Meteorology and Oceanography Center)

• FNMOC provides 16 members once per day out to day 10

• Operational Data exchange between NCEP FNMOC started Aug 2008

• Testing /evaluation until Aug 2009 (unless extra funding, in which case this and next item can be accelerated)

• Operational implementation (pending positive results) Aug 2010

• Evaluation metrics are being designed; verification work started;

• Canada will also be evaluating data; data transfer to Canada still being resolved

Ongoing DiscussionsBetween U.S. and Canada

• Consider extending NAEFS integration to 30-35 days (2009-10)

• Address Intra-Seasonal Forecasting– Weeks 3-4 temperature/precipitation– MJO

Issues – Data Flow

• Today the NWS sends ~6.5 GB of data, four times per day to EC. EC sends ~ 7.5 GB of data twice per day (soon to be four times per day). – Accomplished via internet

• Growing data exchange will require operational data circuits– Neither NWS or EC have been able to fund these

circuits• EC proposes to consolidate all of their

telecommunication exchange requirements to the NWS and NOAA– Recommendation: NCEP and EC proposes formal

study of this approach; provide pros, cons and final recommendation