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A Proposal for NAEFS 8-14-day Forecasts. Edward O’Lenic NOAA-NWS-Climate Prediction Center Camp Springs, Maryland ed.olenic@noaa.gov 301-763-8000, ext 7528. Summary of NCEP Proposal.
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A Proposal for NAEFS 8-14-day Forecasts Edward O’Lenic NOAA-NWS-Climate Prediction Center Camp Springs, Maryland ed.olenic@noaa.gov 301-763-8000, ext 7528
Summary of NCEP Proposal • NCEP proposes to collaborate with CMC to develop and implement an automated version of its 8-14-day outlook, to be issued daily. • The new product would cover Canada, Alaska and CONUS. • Probability of tercile categories of surface temperature and precipitation, and ensemble mean 500-hPa height and anomalies and spread would be predicted. • CMC and NCEP models would provide the primary model input. • Model output would be bias-corrected every 6 hours or so. • Model forecasts would be adjusted for systematic differences between the operational analysis and the reanalysis. • Adjusted model forecasts would all be compared with the reanalysis climate pdf. • Automated techniques will be jointly developed to combine the bias-corrected, adjusted forecasts from CMC and NCEP. • Forecasts from this technique will be carefully monitored, including verification. • A joint decision to implement these forecasts will be made.
Current NCEP Extended-Range Forecast Process Operational Analysis, O Multi-model ensembles from NCEP, CMC, Others, … Daily real-time observations Historical observations, Reanalysis, R Bias-correction of 8-14-day model forecasts using recent 30 days of operational analyses. Compare forecasts to the Reanalysis-based climate PDF • Subjectively-weighted mean 500-hPa 8-14-day height and anomaly forecast Forecaster integrates downscaled T, P tercile probability forecasts Manual Dissemination
Modified Extended-Range Forecast Process Operational Analysis, O Multi-model ensembles from NCEP, CMC, Others? Daily real-time observations Historical observations, Reanalysis, R Bias correction of 6-hourly model output with respect to operational analysis. Quantify systematic differences between the Operational Analysis and the Reanalysis, d*=R-O Adjust all forecasts by d* Compare forecasts to the Reanalysis-based climate PDF • Fully-automated weighted average 500-hPa 8-14-day mean height and anomaly forecast with spread Fully-automated downscale to T, P tercile probabilities Automated Dissemination
Current Official 8-14-day 500-hPa height and anomalies Forecast