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Hurricane Florence and Ottawa’s tornadoes

For heaviest tropical-storm rain in that part of the U.S., Florence now holds the record

OK, OK — I’ll take the blame for our weather turning cold! As my family has so nicely pointed out, I jinxed it when I talked about how long the growing season has been and that we might be able to pull off a record-long season. Then, a couple of days later, what happens? Southern and central Manitoba see their first widespread fall frost.

After that, even the weather models turned against me. They were showing only about a week of cold weather and most of that period looked as if it would be cloudy. I was hoping the clouds would keep the frost away, but a couple of clear to partly cloudy nights allowed for just enough cooling to allow temperatures to drop a couple of degrees below 0 C. Now the weather models show the cold weather sticking around until about the middle of October. I will revisit the long-range fall forecasts next week, but let’s just say that it doesn’t look like much in the way of warm, sunny weather coming any time soon.

For this article I thought we’d do a bit of global weather roundup, starting with August’s global temperatures. It appears August was the fifth warmest on record, according to both NASA and NOAA. The other top four warmest Augusts were in 2016, 2017, 2014 and 2015. This makes it five years in a row that the planet has recorded record-breaking August heat. Looking at the global August temperature of the lower eight km of the atmosphere as measured by satellite, it was the ninth-warmest August on record, according to the University of Alabama-Huntsville.

During August, 186 major weather stations reported new all-time heat records. Japan led the way with 92 records, then South Korea with 28, followed by Portugal with 16, North Korea, 15 and Canada, 14. No stations reported breaking any all-time cold records during the month. There have been 35 national monthly heat records across the globe so far this year. This means that a place in one of those countries has recorded the warmest temperature ever recorded for that country. There have been no monthly cold records. So far in 2018, there have been five all-time national heat records and, just like with the other heat records, there have been no all-time national cold records so far this year.

No Northwest Passage this year

Moving to the polar regions, it looks like the Arctic sea ice is at or near its seasonal minimum as the sun is now setting on the Far North. As of September 17, the sea ice extent was at 4.6 million square km, 1.69 million below the 1981-to-2010 long-term average. If this holds, then this minimum will come in as the sixth-lowest year on record. Cooler-than-average temperatures during July, which slowed the ice melt, were one of the main reasons for the slightly higher-than-expected minimum. The Northwest Passage remained clogged with ice this year and will not become navigable, but the Northern Sea route has been mostly ice free and navigable. To the south, in the Antarctic, sea ice extent is nearing its maximum and is currently running nearly two standard deviations below the long-term average.

The next weather story would be Hurricane Florence. After gaining strength and peaking at a Category 4 storm in the days leading up to its landfall in South Carolina, Florence fortunately dropped down to a Category 1 storm, sparing the region from the catastrophic winds and associated damage that a Category 4 storm would have wrought. That was where the good news ended, though. As the storm approached shore, it slowed down, thanks to a strong ridge of high pressure situated over eastern North America. This slow motion kept part of the storm’s circulation over the ocean and allowed the weakened system to tap into large amounts of moisture. This moisture was then dumped over the Carolinas in the form of heavy rainfall to the tune of over a metre (1,000 mm) in some areas! Florence easily broke the record for the heaviest rainfall from a tropical storm for this part of the U.S.

The final story comes from a little closer to home and is one of those weather stories you would rather not hear about. I’m talking about the devastating tornadoes that hit the Ottawa and Gatineau regions of Ontario and Quebec on Sept. 21. Environment Canada reports two tornadoes moved through this region. The first was classified as an F3 and it moved through Dunrobin, Ont., before moving on to Gatineau. A second, weaker tornado was recorded to have touched down over the south Ottawa neighbourhood of Arlington Woods. Early reports are listing over 275 buildings either damaged or destroyed, with upward of 175,000 customers without power after the storm. Ontario Hydro is expecting some customers to be without power for up to a week. As I write this article, luckily no one has been reported killed, but two people have been admitted to hospital in critical condition.

As we leave the summer season behind in our region, along with the accompanying thunderstorms, our thoughts and prayers go out to these folks.

About the author

Co-operator contributor

Daniel Bezte is a teacher by profession with a BA (Hon.) in geography, specializing in climatology, from the U of W. He operates a computerized weather station near Birds Hill Park.

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