The Canadian Urban km and sub km- scale Weather Prediction System - PowerPoint PPT Presentation

The Canadian Urban km and sub km- scale Weather Prediction System Stephane Belair, s Sylvie Leroyer, Lubos Spacek Environment and Climate Change Canada Montreal, Canada WSN16, Hong Kong, 28 July 2016

The NUMERICAL PREDICTION SYSTEM Buehner et al. (2015) 10 km Caron et al. (2015) 4D-EnVAR UA ICs (6h) (downscaling) Atm. forcing Carrera et al. (2015) Milbrandt et al. (2016) 2.5 km 48h CaLDAS GEM forecasts (3h) UA (6h) (1-km model) OP Surface ICs ICs + LBCs EXP Leroyer et al. (2014) Vionnet et al. (2015) 0.25 km 24h GEM Belair et al. (2016) forecasts

The 2.5-km GEM 4 x 48h runs per day, MSC-Operations Transition of short-range guidance to this system 4D-EnVAR (10km) and CaLDAS (2.5km) for the initial conditions Upcoming... 4D-EnVAR at 2.5km and TEB for cities Column-max reflectivity

GEM 0.25km CONFIGURATION Worth mentioning... Implicit time scheme, semi-Lagrangian advection, terrain- following hybrid vertical coordinate – quite efficient and stable numerics / dynamics Urban processes with TEB Modified 1D turbulent mixing (mixing lengths proportional to model horizontal grid spacing) Milbrandt and Yau cloud microphysics scheme (6 categories, 2 moments) – P3 also being tested.

NEW FOCUS on 0.25km GEM VANCOUVER Coastal and mountain areas... tests over the Canadian West coast, tests over Sochi (Kiktev et al., submitted) Coastal urban areas … tests over Vancouver (Leroyer et al. 2014) Cities... tests over Oklahoma City (Husain et al. 2013, 2014) ROCKIES Mountains, tests over the Canadian Rockies (Vionnet et al. 2015) Severe weather over cities... tests over Tokyo (Belair et al., being submitted)

PAN AM GAMES 2015… TORONTO Interacting lake breezes (18 July 2014)

CLOUD COVER STRUCTURE 1 km 250 m Lake Breeze Fronts From MET-Objects MODIS analyses Aqua (19:00 UTC) 250 m AURORA Sills et al 2011

LAKE FRONT ANALYSES 1400 EDT Front analysis Met-Objects, AURORA PBL height Front (model)

TIME EVOLUTION of PBL HEIGHT STARTING on 0600 UTC 28 July 2015, ending 0600 UTC 29 July LAKE CITY of NORTHERN ONTARIO TORONTO SUBURBS

INTENSE PRECIP OVER TOKYO (TOMACS) 0.25km: PR (07UTC-06UTC) OBS: PR (07UTC-06UTC) (mm) (mm) 90 90 80 80 70 70 60 60 50 50 40 40 30 30 20 20 10 10 5 5 19-h integration 26 August 2011 TOMACS ... A field campaign in the Tokyo metropolitan area with dense observation network was conducted by MRI, NIED and 12 research groups for the summers of 2011-2013. (Belair et al. 2016)

TIME SERIES of PRECIP OVER TOKYO AREA % fraction area w/ Pr(1h) > 30 mm % fraction area w/ Pr(1h) > 20 mm JMA analysis Percent fraction area CTRL covered by hourly NO_URB precipitation greater than 1, 10, 20, 30, and 50 mm. % fraction area w/ Pr(1h) > 10 mm % fraction area w/ Pr(1h) > 1 mm Integration Hour (Belair et al. 2016)

IMPLEMENTATION STRATEGY (GEM 0.25 km) A) Over a few selected areas... cities like Montreal, Toronto, Vancouver are first choice, but some have other ideas (e.g., northern areas, mountains) B) Anywhere, anytime... based on requests and events

IMPROVEMENTS DESIRED 4D-EnVAR UA ICs 2.5 km (6h) 48h GEM forecasts CaLDAS Surface ICs UA (6h) ICs + LCs (3h) Surface – low res analyses Surface – high res “analyses” 0.25 km 24h SPS GEM Forcing forecasts (continuous)

ALONG-TRACK GUIDANCE (Courtesy of Zhipeng Qu and Howard Barker, ECCC)

COMPARISON with MODIS CLOUDS (Courtesy of Zhipeng Qu and Howard Barker, ECCC)

FINAL WORDS ECCC's high-resolution system not currently built for rapid refresh, with nowcasting applications Emphasis is on quality after spin up (> 6h forecasts) R&D for nowcasting + rapid refresh ongoing