WMO NWP Wokshop: Blending Breakout

Blending Breaout Members Paul Joe- Chair Steve Goodman- Rappoteur George Isaac Peter Li Steve Weygandt Rita Roberts JianJie Wang Yong Wang

Issues- Greatest Gap People working on NWP need more focus on High Impact WX, esp Extreme Events Verifying on wrong thing- CSI Need more frequent outputs fomr models at higher time resolution Need to focus on non convective WX elements- wind, fog… Non traditional information Dual pol Lightning threat Satellite Probabilistic nowcast- what refresh rate Model guidance not very good- what level of probability leads to high confidence

Issues- Greatest Gap Need more specificity from the models Within 100 km need more point specific Need high res winds Rapid update cycle to update rapidly changing environment- eg, afternoon pre-convective evironment More sfc obs Dual pol GPS, profilers Improved representation of PBL- inversions Improved microphysics

Issues- Greatest Gap Short lived wx events less predictable Limitation to extend nowcast beyond 2 hours- 2-6 still Big gap due to technology Blending appropriate strategy to extend nowcasting in a physical way Need boundary layer variables from models-background mesoscale forcing This workshop should be held on regular basis to ascertain progress- every 2 years?

Issues- Greatest Gap Support idea for regular workshops- attach to conference- AMS, EGU… Data assimilation close to observation Need analysis/output of near surface parameters- eg, 2 m temperature Better forecast of uncertainty of forecast variables produced by model-eg, motion fields More detailed atmospheric structure- icing potential, visibility require 3D temp, humidity, winds

Issues- Greatest Gap Need NWP model improvement for small scale\ Model physics biases, esp PBL Microphysics Improved meso/storm scale assimilation For mesoscale its an observation problem- inadequate gaps- vertical structure Precipitation assimilation- can we get useful wind information from cloud and precip information Optimal use of radial velocity on storm scale Forecasting impacts harder than forecasting the weather- eg, flooding the issue for Hurricane Irene

Issues- Greatest Gap Poor humidity forecasts- poor boundary layer forcecasts More work on Probabilistic vs Deterministic forecast- 4 km ensemble vs 1 km deterministic Need higher resolution- less than 1 km Need model output at less than hourly- 15 min or better Better info on cloud base Output statistics that users want Need more mesoscale expertise Higher resolution measurements on shorter time scales- 1 min Our classical measurements- were not designed to produce 1 min interval information Need more NWP verification of basic parameters- eg, wind direction Time series verification vs spatial scale, better stats for verification International intercomparison projects on meteorological variables

Projects to Move Forward Projects not obvious Next FDP combine nowcast and NWP WG working together

Projects to Move Forward Underutilization of satellite data and IPT partnering between satellite, radar, NWP community GOES-R project with Ming Xue, Fuzhong Weng, Louis Grasso, Jason Otkin GSD HRRR pre/near storm environment using high resolution hyperspectral soundings from LEO WoF include satellite with cloud ensembles using radar DA Build forward models now for imagers which have rapid updates of 5-15 min- radiances and products

Projects to Move Forward Integrated Product Teams High Impact Weather Working Group to bridge communities Nowcasting Testbed Severe Storms, Hurricanes, Aviation (safety and efficiency/utilization) Europe, Japan, Korea, Hong kong dense surface network