This is not the first day of spring
This is the first day of fall
in the Southern Hemisphere
But in reality, where does the season change? March Equinox? or March 1? (holding true for June, Sept and Dec as well.
Add your thoughts.
A few years back when I was living in Paris in an apartment with no heat, I was very interested in determining when it was going to warm up. So, I found some climate data with my upstairs's neighbor's unsecured internet, and did a whole bunch of calculations with it in Excel.
The one that stuck out to me the most, and which became official for me, was a 91-day running average of temperatures. I used this average to find the 91 hottest days of the year on average (which I would call summer) and the 91 coldest days of the year (which I would call winter), and I had assumed that there would be 91 days in between each of them, which I could call spring and fall, with one random day left over somewhere.
However, when I actually did these calculations, I was surprised to find that the middle of the set of the 91 hottest days and middle of the set of the 91 coldest days are not six months apart. Rather, spring turns out to be about three weeks longer than winter, that is, it takes longer for things to warm up than it does for them to cool down.
Anyway, the days that I calculated in Paris are what I use to determine the beginning of the seasons, regardless of my physical location, which in case you are interested, turn out to be November 30, March 1, June 10, and September 9. Or, if I want things to be even, I go with December 6, March 6, June 6, and September 6, even though, as I look at it now, it seems like I should have gone with the 5th.
Quote from: CtrlAltDel on March 20, 2022, 04:30:12 PM
Anyway, the days that I calculated in Paris are what I use to determine the beginning of the seasons, regardless of my physical location, which in case you are interested, turn out to be November 30, March 1, June 10, and September 9. Or, if I want things to be even, I go with December 6, March 6, June 6, and September 6, even though, as I look at it now, it seems like I should have gone with the 5th.
Other than June 6, in which I would start summer a little later, these are pretty much spot on for what I would say.
Quote from: CtrlAltDel on March 20, 2022, 04:30:12 PM
However, when I actually did these calculations, I was surprised to find that the middle of the set of the 91 hottest days and middle of the set of the 91 coldest days are not six months apart. Rather, spring turns out to be about three weeks longer than winter, that is, it takes longer for things to warm up than it does for them to cool down.
Interesting. I have noticed locally that September is often as hot as June (in fact, my hometown's record high temperature was set in September). Usually the first big cold front of the season comes in late September/early October, but the last tends to show up in late March/early April.
I personally think of the first of the months in question as the start of winter/spring/summer/fall, however.
The magic days for me have been Sept. 10 and Feb. 20 – that is when summer changes to fall and winter changes to spring respectively with temperatures.
Fall to winter and spring to summer are a little more murky. But I typically don't fire up central heating until Dec. 1, and it doesn't get balls-hot until after July 4. We usually get one last kiss of mild weather the first week of June before we start to plunge into hell.
I've always thought it interesting that spring has exactly as much total daylight as summer, and fall has exactly as little total daylight as winter. It's almost like the seasons are on a three-month lag from the change in day lengths.
Quote from: SSOWorld on March 20, 2022, 03:17:16 PM
This is not the first day of spring
This is the first day of fall
in the Southern Hemisphere
But in reality, where does the season change? March Equinox? or March 1? (holding true for June, Sept and Dec as well.
Add your thoughts.
You'll often here TV weatherpeople refer to "meteorological spring/summer/winter/fall." March-May, June-August, September-November, and December-February are how those break down. They go by the calendar instead of by the sun and the amount of daylight vs. darkness.
Yea certainly - but the local weather team I watch doesn't do that - they go by the sun points (equinoxes/solstices).
Quote from: webny99 on March 20, 2022, 10:26:45 PM
I've always thought it interesting that spring has exactly as much total daylight as summer, and fall has exactly as little total daylight as winter. It's almost like the seasons are on a three-month lag from the change in day lengths.
If you're going for the idea that the middle of summer is on the solstice, then it's a lag of a month and a half. It's about three weeks less than that if you go with the 1st of the month. Which makes sense of course. A pot of water on the stove doesn't warm up immediately when you turn on the heat.
I go with the unofficial 12 seasons in the Midwest list now:
- Winter
- Fools Spring
- Second Winter
- Spring of Deception
- Third Winter
- The Pollening
- Actual Spring
- Summer
- Hell's Front Porch
- False Fall
- Second Summer
- Actual Fall
And look at the weather forecast to see which we're in right now.
I don't know of too many places in Texas whose hottest records occurred in July. Most locations happened in either the late summer/early fall (September/October) or late spring/early summer (May/June). In fact, Brownsville, Texas hottest temperature ever recorded occurred oddly enough in March.
Astronomical spring and fall start on the equinoxes; summer and winter on the solstices. Weather forecasting considers the meteorological seasons to start on the first of the month that the astronomical seasons start (https://weather.com/science/weather-explainers/news/2021-02-28-meteorological-spring-astronomical-difference). So forecasters start spring in the Northern Hemisphere on March 1.
Also interesting are the midseason dates. For simplicity, I'll just use Northern Hemisphere examples. Middle of winter is about Groundhog Day (Feb 2). Middle of spring is about May Day. Middle of summer is during the Dog Days of August, Aug 1. Middle of autumn is Halloween. These are all days of celebration for the ancient Celtics, called Imbolc, Beltane, Lughnasa, and Samhain respectively. I've seen these dates moved a day or two depending on the system, so I don't care if you celebrated Samhain on Nov 1 or 2. We've gone through two calendar changes since the Celts were mostly wiped from Continental Europe, first the Julian and then Gregorian Calendar.
Quote from: SkyPesos on March 21, 2022, 01:49:38 PM
I go with the unofficial 12 seasons in the Midwest list now:
- Winter
- Fools Spring
- Second Winter
- Spring of Deception
- Third Winter
- The Pollening
- Actual Spring
- Summer
- Hell's Front Porch
- False Fall
- Second Summer
- Actual Fall
And look at the weather forecast to see which we're in right now.
I know only of 2
- Winter
- Construction.
Quote from: SSOWorld on March 20, 2022, 03:17:16 PM
This is not the first day of spring
This is the first day of fall
in the Southern Hemisphere
But in reality, where does the season change? March Equinox? or March 1? (holding true for June, Sept and Dec as well.
Add your thoughts.
The primary and oldest definition is the astronomical definition: on the equinoxes and solstices. But there's also a weather definition of the seasons, which follows a couple of weeks later.
Quote from: kkt on March 22, 2022, 12:07:48 AM
Quote from: SSOWorld on March 20, 2022, 03:17:16 PM
This is not the first day of spring
This is the first day of fall
in the Southern Hemisphere
But in reality, where does the season change? March Equinox? or March 1? (holding true for June, Sept and Dec as well.
Add your thoughts.
The primary and oldest definition is the astronomical definition: on the equinoxes and solstices.
I’m not sure about that. The earliest I can find is from Varro, which states:
Quote
The first day of spring occurs [when the sun is] in Aquarius, that of summer when it is in Taurus, of autumn when it is in Leo, of winter when it is in Scorpio. As the twenty-third day of each one of these four signs is the first day of the four seasons, this makes spring contain 91 days, summer 94, autumn 91, winter 89, which numbers, reduced to the official calendar now in force [the Julian calendar], fix the beginning of spring on February 7, of summer on May 9, of autumn on August 11, of winter on November 10. But in the more exact divisions certain things are to be taken into account, which cause an eightfold division: the first from the rising of the west wind to the vernal equinox, 45 days, thence to the rising of the Pleiades 44 days, thence to the solstice 48 days, thence to the rising of the Dog Star 27 days, thence to the autumnal equinox 67 days, from there to the setting of the Pleiades 32 days, hence to the winter solstice 57 days, and back to the rising of the west wind 45 days.
Quote from: kkt on March 22, 2022, 12:07:48 AM
But there's also a weather definition of the seasons, which follows a couple of weeks later.
Precedes, I think you mean here.
Quote from: CtrlAltDel on March 22, 2022, 12:57:21 AM
Quote from: kkt on March 22, 2022, 12:07:48 AM
Quote from: SSOWorld on March 20, 2022, 03:17:16 PM
This is not the first day of spring
This is the first day of fall
in the Southern Hemisphere
But in reality, where does the season change? March Equinox? or March 1? (holding true for June, Sept and Dec as well.
Add your thoughts.
The primary and oldest definition is the astronomical definition: on the equinoxes and solstices.
I'm not sure about that. The earliest I can find is from Varro, which states:
Quote
The first day of spring occurs [when the sun is] in Aquarius, that of summer when it is in Taurus, of autumn when it is in Leo, of winter when it is in Scorpio. As the twenty-third day of each one of these four signs is the first day of the four seasons, this makes spring contain 91 days, summer 94, autumn 91, winter 89, which numbers, reduced to the official calendar now in force [the Julian calendar], fix the beginning of spring on February 7, of summer on May 9, of autumn on August 11, of winter on November 10. But in the more exact divisions certain things are to be taken into account, which cause an eightfold division: the first from the rising of the west wind to the vernal equinox, 45 days, thence to the rising of the Pleiades 44 days, thence to the solstice 48 days, thence to the rising of the Dog Star 27 days, thence to the autumnal equinox 67 days, from there to the setting of the Pleiades 32 days, hence to the winter solstice 57 days, and back to the rising of the west wind 45 days.
Quote from: kkt on March 22, 2022, 12:07:48 AM
But there's also a weather definition of the seasons, which follows a couple of weeks later.
Precedes, I think you mean here.
I meant follows. The winter equinox is December 21 or thereabouts, and the great transition is the first week of January, from gradually colder and with common strong storms to quite cold but fewer strong storms. Now, March 21, it's the equinox, but in a couple of weeks it'll be noticeably warmer with stronger sun. A few plants are already in bloom - mostly bulbs - but in a couple of weeks the perennials will be blooming too, and the birds will be paired up into couples and highly territorial. The summer equinox on June 21 isn't really the beginning of the very warm summer weather; July 5 is. The end of the pleasant warm weather isn't September 21, it's the first week of October when the cold and storms start.
Quote from: kkt on March 22, 2022, 01:56:59 AM
I meant follows. The winter equinox is December 21 or thereabouts, and the great transition is the first week of January, from gradually colder and with common strong storms to quite cold but fewer strong storms. Now, March 21, it's the equinox, but in a couple of weeks it'll be noticeably warmer with stronger sun. A few plants are already in bloom - mostly bulbs - but in a couple of weeks the perennials will be blooming too, and the birds will be paired up into couples and highly territorial. The summer equinox on June 21 isn't really the beginning of the very warm summer weather; July 5 is. The end of the pleasant warm weather isn't September 21, it's the first week of October when the cold and storms start.
Ah, by "weather definition of the seasons," I thought you meant the meteorological definition of the seasons.
Quote from: SSOWorld on March 21, 2022, 07:37:49 PM
Quote from: SkyPesos on March 21, 2022, 01:49:38 PM
I go with the unofficial 12 seasons in the Midwest list now:
- Winter
- Fools Spring
- Second Winter
- Spring of Deception
- Third Winter
- The Pollening
- Actual Spring
- Summer
- Hell's Front Porch
- False Fall
- Second Summer
- Actual Fall
And look at the weather forecast to see which we're in right now.
I know only of 2
- Winter
- Construction.
Or, as I heard from a graduation speaker who came from Marquette:
- Winter
- 4th of July
Interestingly, despite living between 42°N and 43°N, we do get all four seasons here. It's just past the equinox, and it doesn't feel like winter. I understand that Marquette is significantly farther north, but I've seen the 12 seasons meme for several locations that are on my latitude.
Doing a Google Images search for "12 seasons meme", I'm getting pretty much the same thing (with occasional variations) for a whole bunch of places, including those with a "third winter" for Texas and Alabama.
Quote from: skluth on March 21, 2022, 07:36:35 PM
Astronomical spring and fall start on the equinoxes; summer and winter on the solstices. Weather forecasting considers the meteorological seasons to start on the first of the month that the astronomical seasons start (https://weather.com/science/weather-explainers/news/2021-02-28-meteorological-spring-astronomical-difference). So forecasters start spring in the Northern Hemisphere on March 1.
Also interesting are the midseason dates. For simplicity, I'll just use Northern Hemisphere examples. Middle of winter is about Groundhog Day (Feb 2). Middle of spring is about May Day. Middle of summer is during the Dog Days of August, Aug 1. Middle of autumn is Halloween. These are all days of celebration for the ancient Celtics, called Imbolc, Beltane, Lughnasa, and Samhain respectively. I've seen these dates moved a day or two depending on the system, so I don't care if you celebrated Samhain on Nov 1 or 2. We've gone through two calendar changes since the Celts were mostly wiped from Continental Europe, first the Julian and then Gregorian Calendar.
Likewise, the equinoxes and solstices were Ostara, Litha, Mabon and Yule respectively. However the Fall equinox isn't really celebrated anymore (save in Canada), and indeed "Mabon" is a recent coinage. This has caused me a real headscratcher when imagining the culture of my fictional country, as I have ideas for the other festivals based on real life but not for this one. And worse, it is specified to be a week long like the season starters (the mid-season ones are three days long). As a side note, I fudge the dates so the grand festivals are on the last week of the corresponding (real life) month, and the traditional and modern New Year dates mimic the real World: traditionally it has been on "the first day of Ostara" (= March 25), while now it is on "the day after the last day of Yule" (= January 1).