1 / 7

The Application of Reforecasts at WPC

The Application of Reforecasts at WPC. Thomas Workoff 1 , Wallace Hogsett , Faye Barthold 2 and David Novak Weather Prediction Center 1 Systems Research Group, Inc. 2 I.M. Systems Group. Potential use of Reforecast Data at WPC. Extreme precipitation forecasting Calibrated probabilities

wind
Download Presentation

The Application of Reforecasts at WPC

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. The Application of Reforecasts at WPC Thomas Workoff1, Wallace Hogsett, Faye Barthold2 and David Novak Weather Prediction Center 1Systems Research Group, Inc. 2I.M. Systems Group

  2. Potential use of Reforecast Data at WPC • Extreme precipitation forecasting • Calibrated probabilities • Extreme Forecast Index • Day 3-10 Products and Hazard Outlooks • Flood, winter precip, and temperature hazards • Improved Precipitation Guidance • Shown to improve QPF scores (Hamill et al., 2006) • Prototype day 4 – 7 winter weather outlook • “Trained” QPF guidance and QPF probabilities

  3. Extreme Precipitation Forecasting Reforecast Prob >3” (shaded) • Atmospheric River Retrospective Forecasting Experiment (ARRFEX) • ESRL provided 2nd generation reforecast data • Reforecast data consistently performed better than raw ensembles, likely due in part to well-calibrated probabilities. • Of all the guidance, participants felt it added the most value to AR extreme precipitation forecasts

  4. ECMWF EFI: Extreme Precipitation • Obtaining a sufficiently long model climatology allows comparisons between current and previous forecasts to identify rare or extreme model forecasts EFI of 1 near Boulder shows that current precip forecast is at the top of model climatology CDF Courtesy of ECMWF, via Tim Hewson and Ivan Tsonevsky

  5. ECMWF EFI: Extreme Precipitation CDFs of the current ensemble forecast show the differences between the current forecast and climatological CDF (black) Forecasts trended toward a bigger event as the event neared (CDFs shift toward the right with time) Courtesy of ECMWF, via Tim Hewson and Ivan Tsonevsky

  6. GEFS EFI: Extreme Precipitation • WPC-ESRL collaboration to develop GEFS-based EFI using reforecast dataset • Temp, precip, and wind hazards on one graphic GEFS EFI values of >.9 signal potential for extreme precip event, relative to the model climatology Courtesy of ESRL, via Tom Hamill and Gary Bates

  7. Winter Weather Outlook (Days 4-7) • WPC prototyping Day 4-7 outlooks in 2014 • Use reforecast probabilities as inputs to hazard outlooks • Better calibrated probabilities than raw ensemble Winter Weather Outlook Reforecast Probability of 10mm QPF

More Related