For the most part, this week will be cool, cloudy and showery. An Upper Low that has been rotating off the BC coast all weekend and drawing warm air up from the south will make a move east today. Tonight the movement of that Upper Low will guide some showers into the South Coast. There is also the potential for some clearing Monday and Tuesday afternoon for the Lower Mainland, creating the potential for some afternoon convective Thunderstorms. It's an "If/Then" statement however: IF we get enough sunshine to cause enough daytime heating and convection...THEN we will see some isolated Thunderstorms pop up.