Q&A: A meteorologist's thoughts on ’bomb cyclone,’ ’pineapple express,’ and being wrong

To be a weather forecaster, you don’t just have to be OK with taking criticism from strangers. You also have to be ready for your own relatives to call you out when your predictions of rain are followed by glorious sunshine.

Last month, a massive low-pressure system hit British Columbia. High winds knocked out power for hundreds of thousands, but in some locations—including the Fraser Valley—the weather remained relatively placid. The lack of disaster following a storm dubbed a “bomb cyclone” led to a number of raised-eyebrows directed towards forecasters (and news organizations).

But Ford Doherty wasn’t surprised by any of it. A weather forecaster for 30 years until he retired in 2018, Doherty says being an Environment Canada meteorologist requires one to admit reality may be different than the future you predicted.

After we wrote about the use of the terms “bomb cyclone” and “atmospheric river,” Ford emailed us with insight into both term’s usage, and his personal thoughts on their history and usefulness.

So we called him up.

‘Things evolve slowly’

Doherty grew up in Eastern Canada, but moved to Vancouver to attend the University of British Columbia. After completing grad school, he was recruited by Environment Canada’s weather service. That led to eight months of training in Toronto, followed by decades of work as a meteorologist based on the west coast.

In his email, Doherty wrote that when he started with Environment Canada in the early ’90s, the office had a checklist for offshore storms dubbed the ‘bomb probe.’ The term bomb cyclone, as used last month, defines a certain type of storm that experiences rapid decline in the pressure at its centre. This explainer from CBS News suggests the term was first used in the 1940s and relates to the ‘bombogenesis’ process that impacts such storms. Doherty told The Current that, in Canada, the type of storm was important because they were particularly hard to forecast.

Tyler Olsen: What do you know about this history of calling these storms bomb cyclones?

Ford Doherty: Things evolve slowly with models. When I started working, and back in Newfoundland, the models were really bad at picking up those kinds of storms—this kind of storm we had the other day here off the island—because the scale is quite small and everything needs to be set up perfectly to get that rapid development of the storm.

It’s almost like a hurricane—I mean, the dynamics are completely different but it does have that tight look to it. So the models were very bad and so not just the deepening of the lows and the track would be affected too. How deep it got would affect the track of the low, so there were these two items that you’re looking at. And this bomb probe I mentioned was a checklist where you’re basically evaluating how much energy was in the system. So that would be how strong the jet was, for instance, and also the orientation of the trough, which would affect how favourable the situation was to have strong development of the storm—meaning the deepening of the low and the strengthening of the winds around it.

So that was what the bomb probe is for. And [November’s] storm was pretty classic. I’m sure it must happen every year, but not quite to that depth maybe, and not quite that close to Vancouver Island. It was a bit closer and usually these things stay offshore. So offshore we’d have hurricane force winds … and we’d have that wind warning out for the marine community offshore, but maybe not toward Vancouver Island. In this case it was actually quite close to Vancouver Island, so that’s why they got the big winds along even the eastern side of Vancouver Island.

TO: I find it interesting. Every profession has their own set of terminology that they use internally and in the last little while it sounds the meteorology profession has started to use them in the broader public—for reasons that make sense. They’re trying to educate the public about the science behind it and the reasons these storms form and trying, I think, to broaden public understanding. But there’s some people who very much don’t want [those terms used].

FD: And for various reasons too. There can be reasonable things about that and not so reasonable, as you know—like the conspiracy theories. But I’ve got a sister in Ottawa, and she’s hearing the news and I got an email from her asking how I was, was there any damage? And to be honest, I wasn’t even aware of the storm. I was busy and inside, and I guess it rained hard and there was a bit of wind. But this is the downside, that people hear this and then expect it’s a catastrophe for anyone anywhere near it. There’s not specificity to it, right? And when you’re doing a real forecast, it’s all about getting the local area right. So Environment Canada has the coast all chopped up into little pieces and each one gets a forecast. and when you just lay out these big terms—bomb-whatever—it’s just not really that useful in some ways. It does catch some people’s attention, but it didn’t even catch my attention—I was oblivious to the whole thing and I’m sure lots of people were. And that’s the bottom line that you’re kind of fighting—if it’s actually a danger to a particular area and people aren’t paying attention. I mean danger in quotes, right—it really depends on what you’re up to.

TO: Yeah, something can leave a lot of people without power, as this one did, and that can be a danger, but it depends exactly how long they’re without power and how many other factors are going on.

FD: The time of year for instance.

TO: I find it interesting too, when we talk about atmospheric rivers, because obviously we had the one three years ago and that reinforced that these things can do an incredible amount of damage that maybe we aren’t aware of, that we only become aware of not so much through the terminology but through the actual event that happens. So I get why people get on edge, then I get why people get confused when something doesn’t materialize. In your email, you wrote about how you kind of like the ‘pineapple express’ term. Can you explain that?

Editor: Doherty spoke about the uncertain origins of the ‘pineapple express’ term and suggested we might want to do our own research. We did some and the popular consensus seems to be that it was adopted by Seattle-area meteorologists in the 1970s who observed that such storms seemed to originate in the area of Hawaii.

FD: To me, [atmospheric river] is just an inelegant, clunky term. How does a river fall on your head anyway? So maybe you can use it, it’s up there in the sky, and there’s this river—it’s all the cloud going by or something like that. But all of a sudden it’s raining on you? What’s that about? So to me, the metaphor isn’t very good. It’s clunky and inelegant like I said. So to ‘pineapple express:’ I liked it at the time. I like it a little bit less now because there’s not a very good connection between pineapples and Hawaii. [Editor: Although pineapples are often associated with Hawaii, the fruit didn’t grow on the islands until the 1700, when it was brought to the area by colonizers. And although Hawaii had some of the world’s largest pineapple plantations in the 1900s, farming of the fruit has all but ceased in the state.] To me, it was kind of more fun than atmospheric river and you have to be fun with those terms because otherwise, people think you're taking it all seriously. The weather's serious, but the term itself, it's just to get attention, right?

TO: It makes it trickier, though, when you're trying to do an exercise like categorizing—because we get these atmospheric curves quite often, and I gather now the ambition is to put in a categorization scheme they can publicly differentiate these and say, ‘Okay, this one's going to be a very bad one, be prepared for road closures, etc.,’ or ‘This one's going to be soggy but you'll be fine.’

FD: Particularly from a West Coast perspective, it’s not enough to talk about atmospheric rivers or whatever, it depends where it is. The bomb [cyclone] we got, California got an atmospheric river, so you still need to look at the forecast. It’s not good enough just to say that. But I guess if it gets people looking at the forecast, maybe it’s worked. So from the media perspective, you would maybe know better how that works.

TO: Yeah. I’ve spoken to some other folks at Environment Canada and they’ve talked about the difficulty of predicting local precipitation. Like the fact that they know these things are coming, but you talk about how you have to look at your local forecast, and sometimes there’s no good way to kind of boil down exactly what’s going to happen with the rain, other than the fact that some place is going to get a bunch of rain.

FD: The atmospheric river is just a regular rainstorm, really, but the classic one for the West Coast is kind of like a hose, you know; you're watering a garden, and you've got it on [the] wide setting on the hose nozzle, right? Now think when you change the nozzle setting to a jet, you get this very focused thing coming out. So that's your atmospheric river.

And it depends on the jet actually sitting there for a while. So we talk about waves in the weather business. So typically with one of these things, you get the initial thing coming in and the rain starts, and then it might kind of weaken a bit, but another wave is coming behind it. So instead of the whole system moving off to the east or away, then this other wave is going to stall it, and then that hose is going to stay on you until that next wave goes by.

So now we're talking instead of just a one-day event, we're talking maybe a two-day event and much more damage. And everything gets saturated. So we got a bigger problem. So forecasting that is difficult because it can be quite narrow and here, of course, it depends on the orientation of the mountains and everything. So there's lots of these local effects.

Doherty cited Environment Canada meteorologist (and Chilliwack resident) Jim Goosen as a key figure in analyzing data to improve the models upon which most local forecasts are based.

Since retiring, Doherty has created a weather based website at clearweather.ca with satellite radar and archived forecasts across Canada.

TO: What's one misconception that people might have about what meteorologists do?

FD: That we always get it wrong! My son in law said that a while ago and I just laughed. It’s funny, because if you are outside and you're actually paying attention, and it's critical to your operation, then boy, it'd be frustrating. The forecast is frustrating because it's a very general forecast for one thing. That's partly why the website that I put together there is there, because the idea is to make it a bit easier for people operating outside to sort of figure out when maybe a window to operate is coming, or something like that, right? So when's the rain gonna start, when's it gonna stop. People like farmers are good for that. The marine community, of course, are very weather conscious. So they might spend that extra minute or two figuring out the weather in the morning? It's that kind of person who the website is for, because there's a bit of a learning curve there. It's not scientific or anything, but it's just a web interface issue.

So I noticed the Environment Canada has a Weather Can app, which I looked at years ago. But I thought this morning, I should take a look at it for you, right? So I've downloaded it and looked at it and boy, oh boy, it's got a learning curve too. It's quite interesting to see.

TO: The interesting thing about your profession—meteorology and trying to communicate things—to the public, is it’s a lot like our [profession] in a way. Everybody wants something customized for them, but you can’t actually customize a weather forecast for 20 or 30 people; you have to do it for a broad group, just on a practical level, right?

FD: That’s a good point because you asked ‘what’s a misconception?’ Well, one, people don’t understand how technical the forecasting is for some of our clients. That’s one other thing I did this morning: just write down who we actually talked to at a higher level than just the general public, meaning they had more specific concerns. So the marine community is the first one; there are log-tows going back and forth across the Georgia Strait all the time—well, not all the time because it’s very limited to the conditions and they don’t want to deal with more than about 15 knots, which is not a lot of wind and is pretty hard to forecast. So we had a marine desk at Environment Canada and they would call. So we had free calls or contract calls for a while and 1-900 calls for a while, and I think it’s going back to free now, from what I heard. So they had very specific in terms of location and in terms of requirements. They didn’t care about the rain but they sure cared about the wind, and that’s a proxy for the wave conditions, the sea state.

So the marine community has a higher level of interest in [the weather] and they’ll call in some times and they get a specific product too. Another one was farmers. We got calls from people wanting to cut hay and they need three or four days for the hay to dry once it’s cut, so they don’t want it to rain during that time. So a location and a specific issue. We had the odd snow-clearing company call, and a lot of calls from construction companies for concrete pours.

So another thing that’s common to this—not the marine community—is that rain is the huge issue.

TO: I have one more: what do you think the public should know more about the weather. And what should the public know more about the weather forecasts they receive?

FD: Geez— Is there one thing? I guess you could look at when do people get in trouble with the weather? I suppose it’s mostly when it snows—not just here but everywhere in the province, although every now and then it’s rain. I can’t help but think with the big flood in 2021, if some of those deaths might not have happened if people were more aware of how unusual that storm was. Because you can see if you are paying attention to the observations, or you’d have to have a degree of it focused that just doesn’t exist. This is where of course the government goes in and they close the highway. So that’s really the solution to prevent people from going along the highway and getting smacked by a landslide.

TO: It feels like a lot of it is inevitably a roll of the dice. You can’t forecast anything 100% and things always change. It feels like in a whole range of areas, from politics to whatever, people sometimes don’t realize how random things are—there’s a standard deviation and statistically sometimes things are going to end up as nothing and sometimes things are going to end up more on the long tail.

FD: That’s one thing that would come up quite often at work: the ability to change your mindset quickly. So you have this image of the future and something comes along and just throws a big wrench in it, and how quickly can you adjust to a new future. You can apply that to people out travelling. All of a sudden conditions are bad and you should really change your behaviour. I just drove to Ontario in September and back and I’ve done this a couple of times. And it’s fascinating when you’re driving a lot for days, and you start to really pay attention to how people drive on the highway. And it’s crazy: people aren’t adjusting to the risks, and that’s in good weather.

This is something that we struggled with as forecasters because all of a sudden things change and you’ve got to change your forecast. and of course you’ve got this emotional block to that because you’re invested in the previous forecast, especially if you’re not the new shift coming in and the old shift is still there. So when a snow storm comes in or whatever and it looks like it’s going to be worse than maybe forecast, people have to change their life to adjust to that.