Compared to West and North Vancouver, I'm sure it gets significantly less rain. If you go to a map and look at Bowen Island, the east side gets more rain than the west side, and its not a big island.
Coastal weather is much more micro climate based than places like, say Chicago. Generally in Chicago if its raining on the east side, its raining on the west side. Because of fjords, inlets, sounds, mountains and large rivers, the climate in Greater Vancouver can vary widely. Part of the city at a higher elevation will get snow, but all around it will get rain. Or as my experience in North Vancouver mountains, I could drive up Mount Seymour while it was raining, then I'd hit an elevation and a very sharp line showed snow on one side of the line and rain on the other, weird to see if you've never seen it before.
And on Gambier Island, it can be great weather in one of the coves while a storm is on in another of the coves.
And in Qualicum Beach where I live, it can be sunny and blue skies, but if you look in all directions there is a circle of good weather with ominous clouds surrounding my area. This happens frequently.
As a rough guide, the closer you are to the mountains, the more likely the rain. Last late September I left Comox and we were headed into Desolation in the West Redonda area but as we got closer the clouds were a nasty very dark grey. I lived in a fjord in North Vancouver and I knew from that experience those very dark clouds weren't going anywhere until they dumped their rain. Instead I headed to Squirrel's Cove, stayed the night then went to the Texada Boat Club for a night or two, and it never rained there.
Also the further north you go, expect more rain, the Broughton area gets significantly more rain than Desolation, but again there are micro climates in the Broughtons.
