Q1- At what time did the cold front pass through Vancouver? Give three pieces of evidence to support your answer.

Q2- Explain the causes of precipitation that occurred between 900 h and 2100 h on December 20. Remember that each bar represents the precipitation that fell in the preceding 6 hours.

Q3- The simplified chart in figure 2 depicts conditions at an unspecified time during the 48-hour period covered by fig 1. What time period (+-3gours) is the surface chart depicting? Giveevidence to support the answer.

Figure 1. Weather conditions observed at Vancouver during the passage of a mid-latitude cyclone. Source: Climate of Vancouver, J. Hay and T. Oke. Cloud Cover (tenths) 8/200 Incoming Solar Radiation (wm) . huja Atmospheric Pressure (mb) ) amn DO Wind Direction (N = ) Wind Speed (m/s) 1-1) Temperature (C) 6 hour precipitation (mm) Relative Humidity (%) 11 t to 1 0/10 34 3 10 PST VANCOUVER, B.C. WINTER LOW PRESSURE DECEMBER 20, 1974 Figure 2. Surface weather map. Source: Climate of Vancouver, J. Hay and T. Oke. 1000 OCCEMBER 21, 1974 CS Scanned with CamScanner NA By 2