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Prof. Sam Lawler
Prof. Sam Lawler
@sundogplanets@mastodon.social  Β·  activity timestamp 3 weeks ago

I have never seen the word "perihelion" in a weather warning before! Wow.

I'm totally saving this to show my students why basic astro 101 is very practical sometimes (...ok maybe the prairies do not have a tidal flooding problem...but... perihelion!!)

A screenshot of a weather warning for Victoria, BC
COASTAL FLOODING STATEMENT
11:47 AM PST Friday 2 January 2026

Abnormal high tides combined with low pressure may produce minor/moderate coastal flooding.

Elevated water levels accompanied by strong winds and waves are expected, exceeding highest astronomical tides.

What: Risk of coastal flooding due to storm surge coinciding with high tides.
When: This weekend, with the highest risk of coastal flooding on Sunday.

Additional information: The South Coast is entering a period of high astronomical tides as Earth reaches perihelion (Earth's closest point to the Sun). Also, a low pressure system will cross the region this weekend. This falling atmospheric pressure will help further elevate coastal water levels beyond predicted tides, thus increasing the risk of coastal flooding.
A screenshot of a weather warning for Victoria, BC COASTAL FLOODING STATEMENT 11:47 AM PST Friday 2 January 2026 Abnormal high tides combined with low pressure may produce minor/moderate coastal flooding. Elevated water levels accompanied by strong winds and waves are expected, exceeding highest astronomical tides. What: Risk of coastal flooding due to storm surge coinciding with high tides. When: This weekend, with the highest risk of coastal flooding on Sunday. Additional information: The South Coast is entering a period of high astronomical tides as Earth reaches perihelion (Earth's closest point to the Sun). Also, a low pressure system will cross the region this weekend. This falling atmospheric pressure will help further elevate coastal water levels beyond predicted tides, thus increasing the risk of coastal flooding.
A screenshot of a weather warning for Victoria, BC COASTAL FLOODING STATEMENT 11:47 AM PST Friday 2 January 2026 Abnormal high tides combined with low pressure may produce minor/moderate coastal flooding. Elevated water levels accompanied by strong winds and waves are expected, exceeding highest astronomical tides. What: Risk of coastal flooding due to storm surge coinciding with high tides. When: This weekend, with the highest risk of coastal flooding on Sunday. Additional information: The South Coast is entering a period of high astronomical tides as Earth reaches perihelion (Earth's closest point to the Sun). Also, a low pressure system will cross the region this weekend. This falling atmospheric pressure will help further elevate coastal water levels beyond predicted tides, thus increasing the risk of coastal flooding.
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πŸ€ ␆
πŸ€ ␆
@walshman23@mastodon.social replied  Β·  activity timestamp 3 weeks ago

@sundogplanets I bet that left you aphelion pretty good!

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Prof. Sam Lawler
Prof. Sam Lawler
@sundogplanets@mastodon.social replied  Β·  activity timestamp 2 weeks ago

@walshman23 Impressive!

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John Francis πŸ¦«πŸ‡¨πŸ‡¦πŸπŸ’ͺ⬆️
John Francis πŸ¦«πŸ‡¨πŸ‡¦πŸπŸ’ͺ⬆️
@johnefrancis@cosocial.ca replied  Β·  activity timestamp 3 weeks ago

@sundogplanets loosen the mooring lines on your prairie schooners after you get back from oyster harvesting.

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llewelly
llewelly
@llewelly@sauropods.win replied  Β·  activity timestamp 3 weeks ago

@sundogplanets yeah, presumably no coastal flooding in Saskatchewan since the Western Interior Seaway receded in the late Cretaceous.

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Jayesh Bhoot
Jayesh Bhoot
@bhoot@mastodon.pub.solar replied  Β·  activity timestamp 3 weeks ago

@sundogplanets Nice! A bit off-topic - the convoluted way I've always remembered perihelion vs. aphelion is that the longer word implies shorter distance (from the sun).

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Prof. Sam Lawler
Prof. Sam Lawler
@sundogplanets@mastodon.social replied  Β·  activity timestamp 2 weeks ago

@bhoot My trick is to remember "perilously close" :)

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Jayesh Bhoot
Jayesh Bhoot
@bhoot@mastodon.pub.solar replied  Β·  activity timestamp 2 weeks ago

@sundogplanets Marvelous! That's my approach too from now on :D

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Prof. Sam Lawler
Prof. Sam Lawler
@sundogplanets@mastodon.social replied  Β·  activity timestamp 3 weeks ago

RE: https://fosstodon.org/@AkaSci/115828276041483994

Ah, perfect, @AkaSci added a diagram and an explanation of why this weather warning is happening!

Happy Perihelion+perigee Moon!

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Pedro Quixote β€½ aka MultiVax
Pedro Quixote β€½ aka MultiVax
@PeterMLittle@mas.to replied  Β·  activity timestamp 3 weeks ago

@sundogplanets @AkaSci I knew that..

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Eric Bono
Eric Bono
@EricBono@beige.party replied  Β·  activity timestamp 3 weeks ago

@sundogplanets The moon WAS super bright last night. Makes sense now. TIL. Thanks!

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SpaceLifeForm
SpaceLifeForm
@SpaceLifeForm@infosec.exchange replied  Β·  activity timestamp 3 weeks ago

@sundogplanets

Failure to give the Moon any credit.

#Astrophysics

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AkaSci πŸ›°οΈ
AkaSci πŸ›°οΈ
@AkaSci@fosstodon.org replied  Β·  activity timestamp 3 weeks ago

@sundogplanets
Curious that they did not mention that the moon is close to perigee around earth, which provides a second contribution to the high tides.

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Prof. Sam Lawler
Prof. Sam Lawler
@sundogplanets@mastodon.social replied  Β·  activity timestamp 3 weeks ago

@AkaSci If they had managed to work "syzygy" into the flooding statement I might have actually fallen off my chair with excitement! But yes, that is interesting!

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shom βœŠπŸ½πŸ§πŸ“·πŸ€ΏπŸ”οΈπŸͺš
shom βœŠπŸ½πŸ§πŸ“·πŸ€ΏπŸ”οΈπŸͺš
@shom@gts.shom.dev replied  Β·  activity timestamp 3 weeks ago

@sundogplanets it's wild to me that the perihelion affects tides, but not the season. That's a strong tilt!

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Leeloo
Leeloo
@leeloo@chaosfem.tw replied  Β·  activity timestamp 3 weeks ago

@sundogplanets
Probably 1% of the people who know the meaning of perihelion studied astronomy.

The other 99% played Kerbal...

(Yes, there's an xkcd).

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Leeloo
Leeloo
@leeloo@chaosfem.tw replied  Β·  activity timestamp 3 weeks ago

@sundogplanets
And then I realised KSP uses periapsis, not perihelion. What's the difference?

Checked Wikipedia. The explanations looked very similar, I had to read them several times before I noticed the difference. Oh yeah, Helios means sun.

So the two words means the same, IF you are orbiting the sun. Which the earth is. But of course Kerbals never orbit our sun, their sun is named Kerbol. So they don't actually use the word perihelion.

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Michael Busch
Michael Busch
@michael_w_busch@mastodon.online replied  Β·  activity timestamp 3 weeks ago

@sundogplanets

I once had to explain to someone how Lake Superior only gets a few centimeters of tide; so the extra couple of millimeters from perihelion versus aphelion does not much matter.

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Prof. Sam Lawler
Prof. Sam Lawler
@sundogplanets@mastodon.social replied  Β·  activity timestamp 3 weeks ago

And after a few cloudy-but-not-rainy days, we're back to an impressive forecast showcasing Weather Canada's ability to say "rain" in as many different ways as possible

A screenshot of the weather forecast for Victoria BC over the coming days, with a rainy cloud icon on every single day, but slightly different text.  Including Rain, Periods of Rain, Showers, and Chance of Showers.
A screenshot of the weather forecast for Victoria BC over the coming days, with a rainy cloud icon on every single day, but slightly different text. Including Rain, Periods of Rain, Showers, and Chance of Showers.
A screenshot of the weather forecast for Victoria BC over the coming days, with a rainy cloud icon on every single day, but slightly different text. Including Rain, Periods of Rain, Showers, and Chance of Showers.
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Catherine Babault
Catherine Babault
@CatherineBabault@mastodon.social replied  Β·  activity timestamp 2 weeks ago

@sundogplanets We have different types of ''rain'' like they have different types of snow in the North. 😁

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Ken Butler
Ken Butler
@nxskok@cupoftea.social replied  Β·  activity timestamp 3 weeks ago

@sundogplanets given where you are, all of those mean "steady wet stuff of slightly varying intensity". (I landed up in BC from a place where "showers" meant "it rains for a bit and then stops", but in BC that's not what "showers" means.)

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Ms. Que Banh
Ms. Que Banh
@PhoenixSerenity@beige.party replied  Β·  activity timestamp 3 weeks ago

@sundogplanets It's floods & rain barrels season. Every nature outing includes muddy boots πŸ˜‚ On the upside, the air smells fab & the trails are empty 🌧

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laurendw
laurendw
@laurendw@mastodon.social replied  Β·  activity timestamp 3 weeks ago

@sundogplanets that forecast is missing the 'rain at times heavy' option

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icastico
icastico
@icastico@c.im replied  Β·  activity timestamp 3 weeks ago

@sundogplanets

My old band was called para!helion - https://archive.org/details/3MilestoMecca

A play on perihelion

3 miles from Mecca : para!helion : Free Download, Borrow, and Streaming : Internet Archive

3 miles from Mecca : para!helion : Free Download, Borrow, and Streaming : Internet Archive

Internet Archive

3 miles from Mecca : para!helion : Free Download, Borrow, and Streaming : Internet Archive
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Schamschula
Schamschula
@schamschula@mastodon.social replied  Β·  activity timestamp 3 weeks ago

@sundogplanets For those living along the coast, these abnormally high tides are known as β€œKing Tides.” Having both the sun and moon near perihelion is the recipe!

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ColesStreetPothole
ColesStreetPothole
@ColesStreetPothole@weatherishappening.network replied  Β·  activity timestamp 3 weeks ago

@sundogplanets Gotta get the science out there however you can. 😎

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