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Perceived air temperature
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This evening I was at the blueberry farm helping
a friend fix a flat tire on his wife's electric scooter.
(How do you pull an axle when there's wires running
into it? I still dunno, because we did an end run
around the problem by patching the tube while it was
still on the wheel).
After we got it done the pair of them went for a ride
together (they each have one) while I hung around
for a bit... that's when I noticed the sun about to
go down. Uh, oh I thought, I'm gonna be cold riding
home (12 miles and a river to cross) because even on
hot days like today it cools off pretty fast here after
nightfall and I only had a thin denim jacket over a shirt
and no windshield (usually I don't use one until September).
So I take off and it's not so bad... for about a mile,
and then suddenly I plunge into cold air; it's really
abrupt. These airmasses must have thin boundaries.
Another mile of this, and then I get to some freshly
paved blacktop and it warms up -- no surprise, especially
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If you are at a state park, swimming in the roped off section of the
lake and you swim through a warm area, be sure you don't open your
mouth and let the water in.
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in calm air after a sunny day.
It's still warm riding across the Queensboro bridge
(it's up high) but then the road drops back to river level
(nearly sea level) and it's like descending into a top-loading
cooler at a grocery store. Well, I suppose warm air rises
and cool air falls, and cool air at sea level hasn't anywhere
lower to fall to.
Then I reach the steep road up into my neighbourhood
at several dozen meters altitude, and sure enough it warms
up as I climb the hill. Since I don't have a thermometer
I can't tell how many degrees C it takes to make a difference
between perceived "warm" and "cool", but I can feel lots
of temperature changes even on a short ride.
The Environment Canada readings for Vancouver today were:
1600 23C 60%RH WNW 13 km/hr
2100 21C 59%RH Calm (6 mins after sunset)
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