Victoria weather sites: Gonzales vs. the Airport

One of my pet peeves is that the official weather recording site for Victoria is located at the Victoria International Airport - which is actually in North Saanich, 25 km north of Victoria. This would be okay if the climate at the airport was representative of Victoria, but it really isn't. This partly goes back to the rainshadow effect. The core area of Greater Victoria (particularly the City of Victoria, Oak Bay, and the southeastern part of Saanich) is much more affected by the Olympic Mountain rainshadow than the Westshore or the Saanich Peninsula (where the airport is located). In addition, the moderating effect of the Strait of Juan de Fuca means that the core area (especially those parts near the Strait) tend to be milder (warmer in the winter, cooler in the summer) than the Saanich Peninsula.

So if not the Airport site, then what weather recording site should be used to represent Victoria? The Gonzales weather station used to be Victoria's official recording site, and it has a longer period of record than the Airport (weather records started at Gonzales in 1898 versus 1941 for the Airport). Gonzales is located just over 3 km southeast of downtown Victoria. It is located on top of a small hill close to the Strait of Juan de Fuca. Some might argue that Gonzales isn't very representative of Victoria either. Being close to the Strait, it tends to have cooler high temperatures than inland areas, especially during the summer. Also, the rainshadow effect in Victoria is strongest in the southeast corner of the region - very close to Gonzales, to it does tend to be one of the driest locations in the region. While Gonzales is slightly drier than some other parts of the core area of Victoria, precipitation levels are still much more representative of Victoria than is the case for the Airport site.

Comparing the two sites, you can definitely see the impact of the rainshadow and the moderating effect of the Strait. Victoria Gonzales averages 641 mm of precip. annually, while the Airport averages 883 mm - 38% more. Similarly, Gonzales gets about 20 cm of snow annually while the Airport gets nearly 40 cm. Gonzales also gets more sunshine - an average of 2,203 hours at Gonzales versus 2,109 hours at the Airport. Gonzales is also milder, with an average of 11 days each year when the temperature dips below freezing, compared with 46 days at the Airport.

The Airport statistics noted above are based on 30-year normals - averages over the 30 year period between 1981 and 2010 as reported by Environment Canada.  For Gonzales, things are a little more complicated.  Gonzales was the official Environment Canada weather site for Victoria for 90 years, and comprehensive climate data was recorded during this period.  Unfortunately, Gonzales was essentially decommissioned in July 1988 and these comprehensive measurements ended.  In November 1993, Environment Canada opened an automatic weather station at Gonzales which records temperature, total precipitation, wind speed, humidity and atmospheric pressure. As a result, there is a roughly 5 year gap in the data, between August 1988 and October 1993.  Unfortunately, snowfall and sunshine are no longer recorded at Gonzales.  For snowfall, beginning the winter of 1988-89, I have used data from Victoria Phyllis Street, a nearby Environment Canada volunteer site (located in the Ten Mile Point area of Saanich) with a roughly similar climate to Gonzales.  The Phyllis Street data ends in 2000, so since then I have been measuring snowfall at my home in James Bay.  There is really no alternative for measuring sunshine, so that ends in 1988.  As a result, I have used a 30-year average for the most recent 30 year period available (1958-87).