Victoria records 53 days with no measurable rainfall - the third longest such dry streak on record

 Following the unprecedented heat wave in late June 2021, temperatures in Victoria returned to normal, but the dry sunny weather continued.  

Victoria Gonzales received no measurable rainfall in July.  That is the 7th time that Victoria has experienced a July with no measurable rain (the other times being 1914, 1922, 1926, 1958, 1984, 2018).  It is also the 12th time overall that Victoria has had a calendar month with no measurable rain.  

In all, there was no measurable rain recorded at Victoria Gonzales from June 15 to August 6 - a total of 53 days.  That makes it the third longest such dry streak recorded in Victoria over the past 120 years.  The longest dry streak was 63 days, from June 15 to August 16, 1926.  The second longest was 54 days from July 17 to September 8, 1986 - many residents will remember that year for the great weather at Expo 86.  

The chart below shows the longest dry streaks ever recorded in Victoria.  Of note, 4 of the 10 longest dry streaks occurred in the 1920s, which was the driest decade on record in Victoria for both average annual precipitation (601 mm) and average summer rainfall (34 mm for the June to August period). The past 10 years (2011-20) was the second driest decade for summers, with an average 36 mm of rain, which could indicate the beginning of a trend towards even drier summers that most climate models predict for our area as a result of climate change.  Conversely, none of the longest dry streaks was in the 1990s, which was one of the wettest decades (along with the 1930s) in Victoria, for both total annual precipitation and summer rainfall.  

How rainy is Victoria compared with other cities in Canada? It depends on where in the region you are.

When talking about Victoria's climate, this blog primarily uses data from the Victoria Gonzales weather station.  This station, located in the southeast part of the City of Victoria near the border with Oak Bay, was Victoria's official weather station for many decades.

Thanks to its southeastern location, precipitation at Victoria Gonzales is strongly impacted by the Olympic Mountain rainshadow.  That influence tends to lessen the further north and west you go in the Greater Victoria region.  Thus, when we've stated on the blog that Victoria gets less rainfall than most cities in Canada, that is based on rainfall in Victoria Gonzales, and is not necessarily true for some of the wetter parts of the region.

Below is a chart that compares average annual precipitation at various locations in Greater Victoria with major cities across Canada.  As you can see, annual precipitation at both Victoria Gonzales (608 mm) and the University of Victoria (643 mm) is relatively low.  Across Canada, only cities in the B.C. Interior and on the Prairies are drier.  In fact, just 18% of Canada's urban population lives in cities with lower annual precipitation than these two locations.   Esquimalt Harbour (861 mm) and the Victoria Airport in North Saanich (883 mm), fall more in the middle of the pack among Canadian cities, with roughly half of Canada's urban population living in cities that are drier than these locations.  Meanwhile, Langford (1133 mm) and Sooke (1236 mm) get more annual precipitation than most cities in Canada: only cities in southwestern B.C., parts of Quebec, and Atlantic Canada get more precipitation.  In fact, 81-86% of Canada's urban population lives in cities that are drier than these locations.

Canadian Climate Comparison: which cities get the most and least rainfall?

In the last post, we compared temperatures in the 41 largest urban areas in Canada (those with 100,000 or more people).  In this post, we'll compare precipitation amounts.

The chart below compares average annual precipitation in the 41 largest cities in Canada, ranked from lowest to highest.  The driest city is Kamloops, in the B.C. Interior, with an average of 287 mm annually.  The remaining top 10 driest urban areas in Canada are mostly in the Prairies, along with two more B.C. cities: Kelowna and Victoria.  People are often surprised that Victoria ranks so high among the driest cities in Canada.  Putting this another way, Victoria gets less annual precipitation than nearly 82% of Canada's urban population.  Victoria's low rainfall is thanks to rainshadowing, from both the mountains on Vancouver Island and from the Olympic Mountains in Washington State.  The wettest of the 41 cities is Chilliwack, followed by Vancouver and Abbotsford.  St. John's and Halifax round out the top 5 wettest cities in Canada.  It's striking that cities in Coastal B.C. occupy the top 3 spots for the wettest urban areas in Canada, while nearby Victoria ranks as the 10th driest out of the 41 cities.

Average Annual Precipitation for Urban Areas in Canada

Seasonal variations in precipitation are also important when comparing Canadian cities.  The chart below ranks summer (June to August) precipitation for Canada's cities.  With just 52 mm of rainfall, Victoria is by far the driest urban area in Canada during the summer.  The next driest city - Kamloops - gets nearly 70% more summer rainfall than Victoria, most cities outside of B.C. - such as Calgary, Toronto, or Montreal - get 4 to 5 times as much summer rainfall as Victoria.  The top 6 driest summer cities are all in B.C. - 4 on the coast and 2 in the Interior.  This really shows the impact of the seasonal variation of precipitation in Coastal B.C.  While we just saw that Vancouver ranks as the second wettest city in terms of total annual precipitation, it is the 5th driest city in Canada in terms of summer precipitation.  The wettest summers tend to be in Atlantic Canada and Quebec.

Average Summer Precipitation for Urban Areas in Canada

Victoria also has relatively dry springs - ranking as the 9th driest among Canadian cities.  Fall precipitation in Victoria is closer to the average, with the city ranking as the 17th driest out of 41 cities.  Winter is a different story.  The chart below ranks winter (December to February) precipitation for Canadian cities.  Saskatoon has the driest winters among Canadian cities, with just 37 mm of precipitation.  The top 10 driest winter cities are all located in the Prairies, the B.C. Interior, or Northwestern Ontario.  Victoria ranks as the 31st driest winter city (or the 11th wettest), with 264 mm of precipitation.  The top 5 wettest winter cities are exactly the same as the top 5 wettest cities overall, with Chilliwack in first place with a whopping 659 mm.

Average Winter Precipitation for Urban Areas in Canada