May was a great month for planning outdoor events in our area, but the dry, sunny weather is getting a little worrisome.
Weather forecasters at the Southeast Fire Centre in Castlegar say their records show May was the driest in a quarter-century. And it follows two other months that had lower-than-usual precipitation.
“It was definitely dry,” says Ron Lakeman, a weather forecaster at the Southeast Fire Centre. “We have definitely been at a deficit in the last few months.”
The total amount of rain in May was only 23.7 millimetres, or 34 per cent of normal. It was the third driest May on record. Only May of 1970 and 1995 were drier.
The cause of the dry weather was an upper ridge of high pressure centred off the coast at the start of the month, then over the interior. It dominated with dry and warmer trending conditions during the initial two weeks of May.
A large Pacific system followed but generally missed the West Kootenay, with light amounts of rain from the 14th to 17th. The only other measurable rainfall during the month was the 12.6 millimetres on the 24th and 25th.
High pressure dominated for dry and unseasonably warm conditions again during the final five days of the month.
Impact on forest fires
But while May didn’t help relieve the rain deficit, Lakeman says it’s what happens in the next few weeks that’s important for forest fire season.
“Rainfall in May is not one of the crucial months” when it comes to forest fires, he says. “June, July and August are the mains.”
Lakeman notes that of the two previous driest Mays, 1995 had no significant fire season, while 1970 did.
So he’s keeping a close eye on the skies for the next week or so, when two systems are forecast to bring some rain to the region.
“If that’s the start of something wetter, then there’s relief on the horizon,” he says. “But if the [high-pressure] ridge rebuilds and sticks, or the next system misses us, the deficit we have right now in terms of precipitation can certainly have some ramification coming into the crucial months of June, July and August.
“To get some precipitation over the next four weeks will have a large influence as to what things are like as we go through the heart of the summer.”
Not only was it dry, but it was a warm month as well. The hottest day was the 29th, when the mercury hit 31.4 degrees. The coldest temperature was 1.6 degrees, hit on the 3rd.
No temperature records were broken this month.