Holiday weather - Canada Day

I thought I would start a series looking at the typical weather in Victoria for various holidays.  First up is Canada - July 1.

While Canada Day doesn't quite fall in the very driest time of year in Victoria (which begins about a week or so later), it is still quite dry.  We actually had a few light sprinkles on Canada Day this year (2016), but there was no measurable rainfall at Victoria Gonzales.  If you look at the full period of record at Gonzales, going back to 1898, there has been measurable precipitation on 14.4% of those years.  More recently, it's been even drier on Canada Day: in the last 22 Canada Days going back to 1995, there has only been measurable rainfall once, when 0.8 mm fell on Canada Day 2010.  That works out to a 4.5% chance.  When it has rained on Canada Day, amounts have generally been light, and the average precipitation for the day (including all those years with no rain) is just 0.3 mm.  The most rain ever recorded on July 1 in Victoria was 8.6 mm in 1933.

Our neighbors to the north in Vancouver don't fare nearly so well when it comes to having a dry Canada Day.  The chance of having measurable rainfall on July 1 in Vancouver is 32% and the average amount of rainfall 3.1 mm - ten times as much as Victoria.  Even if you just look at the 1995-2016 period, which has been so dry on Canada Day in Victoria, it has been much wetter in Vancouver, with measurable rainfall on 8 of those 22 years.

There's a much better chance of having measurable sunshine in Victoria on Canada Day than having measurable rain.  During the period from 1951-1988, there was measurable sunshine on Canada Day 89% of the time.  That's actually quite low compared with other days nearby in the calendar: during that same period, every June 30 had measurable sunshine (100%) while on July 2 there was measurable sunshine 97% of the time.  The average amount of sunshine on Canada Day is 9.3 hours, or about 60% of the 15.6 hours that's possible for that date.

The average high and low temperature for Canada Day at Victoria Gonzales is 19.4/10.8 degrees.  The warmest July 1 was 1942 when the temperature hit a sweltering 33.9 degrees.  The coolest was 1979 when the temperature topped out at a very chilly 13.0 degrees.  The temperature gets above 20 degrees at Victoria Gonzales on only about one third of Canada Days.  It's a different story if you  move inland in the Victoria region: at the University of Victoria, the average temperature on July 1 is 22.9 degrees, and it gets above 20 degrees nearly 80% of the time on Canada Day.

The Year So Far

We've completed six months of 2016, so I thought it would be worthwhile to take a look at the weather in Victoria so far this year.

In terms of temperature, this has been a record warm start to the year.  Last year (2015) was the warmest year on record at Victoria Gonzales, and the first six months of 2015 were also the warmest ever recorded (10.8 degrees).  In 2016, we have beat that record, with a mean temperature of 10.9 degrees for the first six months of the year.  Every month so far in 2016 has been above normal temperatures.  Will we beat 2015 the the whole year record?  Probably not.  July 2016 is so far looking to be much cooler than last July, and with La Nina looming, the end of the year may also be cooler.

The chart below compares daily high and low temperatures with the 30-year averages.  You can clearly see that temperatures have been pretty consistently above average, although we've had a few short stretches of average or slightly below average temperatures in late May and into June.

Daily High and Low Temperatures, January to June 2016

Things are a bit closer to normal when we look at precipitation.  In the first six months of 2016 we have had 261 mm of rain, compared with the normal of 296 mm.  Incredibly, nearly one quarter of the year's rain so far this year fell on a single day - February 15 - when we had a record-breaking deluge of 62 mm.  Without that one day, we would be under 200 mm for the year so far.

The chart below shows daily and cumulative rainfall at Victoria Gonzales for the first six months of 2016.  You can see that we have generally trended below average for most of the year.  You can also see that incredible deluge that we had on February 15.

Daily and Cumulative Rainfall, January to June 2016

Mixed weather in June

After a string of months with warmer and drier than normal weather in Victoria, things were a bit more mixed in June.

The mean temperature for the month was 15.5 degrees, 1.0 degrees above the 30-year average of 14.5 degrees.  The average daily high/low at Victoria Gonzales was 19.7/11.2, again above the average of 18.5/10.4.

The chart below compares the daily high and low temperatures with the averages for June.  The warmest weather of the month was during the first week of June, with temperatures topping out at 30.2 degrees on June 5.  Only about one in five Junes at Victoria Gonzales sees the maximum temperature exceed 30 degrees, so that is relatively uncommon, especially for early June.  The rest of the month was pretty close to average.

Daily High & Low Temperatures at Victoria Gonzales, June 2016

After a dry April and May, precipitation in June was a bit above average, with 26.3 mm compared with the normal 20 mm.  There were 8 days with measurable precipitation in June, slightly above the average of 7 days.  The greatest amount was 9.4 mm that fell on June 15.

While the Victoria Airport typically gets more rain than Gonzales, this June it actually received slightly less - about 24 mm vs. 26 mm at Gonzales.  In Vancouver, there was 58.2 mm at the Airport and 84.1 mm downtown at the Harbour.

The chart below compares daily and cumulative rainfall in June 2016 with the average cumulative rainfall for June.

Daily & Cumulative Rainfall at Victoria Gonzales, June 2016