Analyzing 30 Years of Data! Which Day Has the Highest Probability of Sunshine in a 365-Day Year?

2023.08.19 published

殿堂記事

If Possible, I Want to Have My Wedding on a Sunny Day!

"After Rain, the Ground Becomes Firm"

"Rain on a Wedding Day is a Gift from Angels"

"Rain on a Wedding Day Represents a Lifetime of Tears for the Couple (meaning they will live happily without shedding tears from now on)"

There are various positive traditions about rain weddings, but...

If possible, you still want to have your wedding under a beautiful blue sky, right?＊

Do You Know About "Tokuibi"?

For those who think, "Since I can't change the weather, whether the wedding day is sunny or rainy is up to luck…" there's a little fact you should know.

It's the concept of "Tokuibi" (特異日).

Tokuibi refers to dates that statistically have a high occurrence of "sunny (rainy or cloudy) days." These are days when a specific weather condition is quite likely to happen, so it's not just a coincidence.

Tokuibi is a globally recognized concept, and in Japan (Tokyo), here are some examples. (From Wikipedia)

✅ January 16: Sunny Tokuibi

✅ March 14: Sunny Tokuibi

✅ March 30: Rainy Tokuibi

✅ April 6: Cold Weather Tokuibi

✅ June 1: Sunny Tokuibi

✅ June 28: Rainy Tokuibi. There is a 53% chance of rain in Tokyo.

✅ July 17: Rainy Tokuibi. It is also known as "Yujiro Rain," named by Masamitsu Morita, coinciding with the death anniversary of Yujiro Ishihara.

✅ August 18: Heat Wave Tokuibi

✅ September 12: Rainy Tokuibi

✅ September 17: Typhoon Tokuibi. Statistically, this is a day with a high occurrence of typhoons making landfall in Japan.

✅ September 26: Typhoon Tokuibi. Statistically, this is a day with a high occurrence of typhoons making landfall in Japan.

✅ November 3: Sunny Tokuibi

<Investigating Data from the Japan Meteorological Agency>

The Japan Meteorological Agency publishes daily weather occurrence rates for Tokyo.

➡ Daily Weather Occurrence Rates in Tokyo

The statistical period for the data published on this page is 30 years from 1981 to 2010. Although the data for the last 10 years is not included, brides who want to have their wedding on a sunny day can utilize this kind of data as one option.♩

In this article, I thought about things I would want to keep in mind while deciding on a wedding date considering the weather:

✅ Days when there's a high probability of sunshine

✅ Days when there's a high probability of rain

✅ Days when there's a high probability of snow

I've put together a list of these＊

Days with an 80% or Higher Chance of Sunshine

January 1

January 3

January 5

January 10

January 11

January 14

January 15

January 25

January 26

January 27

January 30

February 11

November 23

December 2

December 4

December 10

December 15

December 16

December 20

December 23

December 24

December 25

December 27

December 28

December 29

December 30

December 31

◆ Days with a 50% or Higher Chance of Rain

May 24

June 9

June 14

June 25

June 26

June 30

July 3

September 15

September 16

September 30

October 1

October 6

October 8

October 9

◆ Days with a 20% or Higher Chance of Snow

January 12

January 23

February 1

February 3

February 17

February 18

February 24

Not Just Luck! Analyzed "Days with a High Probability of Sunshine" from Past Weather Data＊

Here are the references for choosing your wedding date,

✅ Tokuibi

✅ Analysis data of daily weather occurrence rates over the past 30 years

I have introduced them＊

As is obvious, this is not a guarantee but merely reference data; however, statistics are quite impressive. (Even today, which is considered a rainy Tokuibi, it is indeed raining!)

When you have several candidate dates, it might be beneficial to choose Tokuibi or days with many sunny occurrences.♩

➡ Wedding productions for sunny men and women, and productions if the wedding day is rainy, etc.

@nagisa_marry