BC Day - the most reliable weather of the year in Victoria

I'm continuing my look at average weather on major holidays in Victoria.  We last looked at Canada Day - next up is BC Day.

BC Day doesn't fall on a specific day - it is the first Monday in August.  That means, it can fall anywhere from August 1 to 7.  For the purposes of this discussion, I will use the weather averages for August 1-7.  This period is right in the middle of the driest, sunniest, and warmest time of year in Victoria (which generally extends from mid-July to mid-August).  

Looking at the 1981-2010 period, there is just a 9.1% chance of measurable rain on BC Day.  By comparison, the chance of rain is 14.4% on Canada and 20.0% on Labor Day, so the BC Day long weekend is definitely the most reliable for camping or other outdoor activities.  In fact, Victoria's weather on BC Day is more reliably dry than any other city in Canada.  The chance of measurable rain on BC Day is nearly twice as high in Vancouver (16.7%), and nearly four times as high in Calgary (33.2%) and Toronto (33.3%).

BC Day is also generally the sunniest holiday in Victoria.  There is a 97.3% chance of getting measurable sunshine on BC Day in Victoria.  On average Victoria gets 10.5 hours of sunshine on BC Day, meaning that it is sunny about 72% of daylight hours.  That compares with 9.3 hours (60% of possible) on Canada Day.  While that's impressive, BC Day actually just misses the sunniest time of year in Victoria: during the last 10 days of July there is an average of 12.1 daily hours of sun, meaning it is sunny 81% of daylight hours during this period.  Again, Victoria is more reliably sunny on BC Day than other major cities across Canada.  While Victoria gets 72% of possible sunshine on BC Day, Vancouver and Calgary both average 63% and Toronto averages 58%.  Even Penticton in the "sunny Okanagan" averages just 62% of possible sunshine on BC Day.

The average high and low temperature for BC Day at Victoria Gonzales is 20.6/11.9 degrees, making it the warmest holiday of the year.  The warmest it's been during the first week of August is 32.8 degrees on August 6, 1942 (which was also the year Victoria had its hottest Canada Day on record).  The temperature gets above 20 degrees about half the time during the first week in August at Victoria Gonzales.  It's a different story if you  move inland in the Victoria region: at the University of Victoria, the average temperature during the first week in August is 24.0 degrees, and it gets above 20 degrees nearly 90% of the time during the first week in August, and above 25 degrees nearly 40% of the time.