Should you wear long johns? There's a map for that

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Long johns are popular in Canada, as in other cold countries. If you have to brave deep-freeze temperatures, you’ll be glad you’re wearing them. But when exactly do the benefits of long johns outweigh the trouble and discomfort of getting them on? Only Canada has a daily forecast on whether and where they should be worn.

Every weekday since 2011, an index rating and weather map has been produced by the ‘Long John Index Service of Canada’ – despite the official-sounding name, not an official government agency.

Nor is the Long John Index itself at all scientific. “It is used for entertainment and gambling purposes, and should not be confused with your preferred weather service”, the LJI website disclaims.

Yet there is method to the index, which runs on a scale from 1 to 5, 1 being the lowest point (at the freezing point of 0°C/32°F). Basically, for every 10°C the temperature drops, the index goes up by one point. And the time spent outside without long johns decreases.

At LJI 1 (0°C to -9°C, no wind chill), you shouldn’t need any long johns unless you’re spending 7 or more hours outside and standing as still as “one of those creepy living mannequins”.

At LJI 2 (same temperature range as above, but with “wind strong enough to knock over mini vans”), you should spend no more than two hours outside without long johns.

LJI 3 means temperatures of -10°C to -19°C (14°F to -2°F). “Your thighs will give you that ‘burny feeling’, which is your body’s way of telling you aren’t dressed warm enough”. So don’t stay out withoug long johns for more than an hour.

LJI 4 is from -20°C to -29°C (-4°F to -20.2°F). If you’re staying out longer than 15 minutes without long johns, “you’ll feel like an astronaut, venturing out into the cold reaches of space. Though space is probably warmer”.

Anything below -30°C (-22°F) is LJI 5. Length of time you can be outside without long johns: 0 seconds. “Long Johns should be worn INDOORS. Don’t even bother going outdoors. Don’t even look at the outdoors, unless you have Long Johns for your eyes. It’s that cold. Instead, make some tea, grab a nice book, wrap yourself in as many towels and blankets as you can and just stay inside. When it’s nice out, someone will tell you”.

So what does the Long John Index for Canada look like? Each day, two LJIs are forecast for 38 Canadian cities, one for the morning, the other for the afternoon. On 31 January – no need get your long johns out in Vancouver, Victoria, Kelowna, Penticton or St. John’s. Perfect zero scores in all five cities.

On the other end of the scale: Yellowknife, Inuvik and Alert. All three places score 5/4. No need to take them off. Fort St. John, Whitehorse, Edmonton, Grande Prairie, Portage La Prairie and Iqaluit are barely doing better (4/4). Compared to that, things sound pretty balmy in Kamloops, Toronto (both 1/0), Thunder Bay and Halifax (both 1/1).

The map helpfully adds that “everything above this line is frozen”, referring to the border that separates the Yukon and Northwest Territories from points south. Just to the east, Nunavut is “shut”. In the northernmost bit of Canada, it’s currently so cold that “I think my breath just froze”. By comparison, temperatures are verging on the pleasant in British Columbia (“snow schmow”) and Newfoundland (“noop!”).

The prairie provinces are coping: Alberta is having a “winter dance party”, and Saskatchewan and Manitoba are finding it “cold, but less cold than cold”. If you’re in Ontario, “you should probably wear a hat”, while your dogn in Québec “should wear those weird boot things”. What, don’t dogs get to wear long johns?

Here’s the website for the Long John Index. You can also follow the LJI on Twitter and Facebook.

Strange Maps #884

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