Forecast Exercise Location: Whistler, BC Date: Saturday 13 February 2010 FXCN10 Synopsis/Model assessment...deepening low near 48N 145W with wave pushing northeastward. Warm front is expected to reach the coast early Saturday morning with precipitation arriving around noon and freezing levels rising to above the North Shore mountains. Consequently initially rain will spread to all coastal venues and well up inland venues but should fall back overnight as cold front approaches. Heaviest precipitation should occur late this afternoon and this evening as upslope increases with southeast flow strengthening. Winds could gust up to 60 km/h later today at the Cypress venue causing potential problems for the grandstands in exposed areas. Rainfall amounts of 40 to 60 mm by Sunday morning with highest amounts on north shore mountains so warnings are being considered for the morning. Rainfall amounts inland in whistler area expected to be more like 15 to 25 mm in the same time period. Most of rainfall is due to upslope enhancement along north shore mountains with strong southerly gradient. This system is moving in faster than previously indicated and moves through during Sunday morning as cold front moves inland and drier air spreads in its wake. Consequently highest precipitation amounts are now overnight with lesser amounts on Sunday which looks reasonable. Exercise Prepare a spot forecast for the Whistler venue, issued at 1900 UTC on 13 February. Worksheet 1. Reference Material Map of British Columbia Map of Southwestern BC GE Map of Whistler 2. Observed Weather to 13 Feb 1800 UTC Surface Analysis 1200 UTC 850mb 500mb 250mb Soundings 13 /12Z Q12 P12 T12 CYQQ CEWP CYZT Surface weather VOA VOB VOC VOL VOT All Radar Radar Angles Cross Sections Doppler V Reflectivity PPI Satellite 57 Deg Anim_VR_57 Anim_LogZ_57 73 Deg Anim_VR_73 Anim_LogZ_73 360 Deg Anim_VR_360 Anim_LogZ_360 LogZ VR IR Large sector WV Large sector Wind Profiler Basic profile to 2500 m Profile to 1500 m 3. Model Guidance GEM REG 4 panel Clds_QPF Pcpn_thckns GFS loops 500mb Vorticity Sfc_pcpn 850t_wind GEM LAM 2.5km QPF Snow Density Visibility X-Section Prog Soundings (animations) - LAM issue: ddhh VOA VOC WSK YVR 1 km LAM 1311 A1 C1 K1 R1 2.5 km LAM 1306 A2 C2 K2 R2 2.5 km LAM 1315 A2 C2 Meteograms VOA VOB VOL WSK YVR Precipitation A1 B1 L1 K1 R1 Snow Wind A2 B2 L2 K2 R2 Temp A3 B3 L3 K3 R3 A4 B4 L4 K4 R4 MOS Guidance Issue 0300Z Issue 1500Z Appendix Morning Forecast from PSPC CPCN30 CWVR 131300 FORECASTS FOR THE WHISTLER - ALPINE VENUES ISSUED BY ENVIRONMENT CANADA AT 5.00 AM PST SATURDAY 13 FEBRUARY 2010 FOR TODAY AND SUNDAY WITH AN OUTLOOK FOR MONDAY TO FRIDAY . THE NEXT SCHEDULED FORECAST WILL BE ISSUED AT 11.00 AM. WHISTLER - ALPINE VENUES TODAY.. CLOUDY. FLURRIES AND RAIN SHOWERS BEGINNING LATE THIS MORNING CHANGING TO RAIN THIS AFTERNOON. FOG PATCHES THIS MORNING. FOG LATE THIS AFTERNOON. HIGH PLUS 3. TONIGHT.. RAIN CHANGING TO PERIODS OF SNOW MIXED WITH RAIN OVERNIGHT. RAINFALL AMOUNT 10 TO 15 MM EXCEPT SNOWFALL AMOUNT 2 CM. 15 CM AT THE TOP OF THE COURSE. FOG. LOW PLUS 1. SUNDAY.. PERIODS OF SNOW MIXED WITH RAIN CHANGING TO RAIN AT TIMES MIXED WITH SNOW NEAR NOON AND ENDING IN THE AFTERNOON THEN CLOUDY. SNOWFALL AMOUNT 5 CM. RAINFALL AMOUNT 10 MM. FOG DISSIPATING IN THE MORNING. HIGH PLUS 3.