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In the same vein if the weather is good today, there is s large probability that it’s good tomorrow, but if it’s been good for 14 days there is an increasing probability of bad weather.



If the process is truly random however, then that no longer holds and you risk falling prey to the gambler's fallacy. If you flip a coin and get heads 14 times, you're still equally likely to get heads or tails the 15th time, despite the probability of getting heads 15 times in a row being very low.


Why would this be true? What if we, by luck, had 14 days of good weather at the end of monsoon season? Your observation seems to be a function of the probabilities changing as the calendar date advances and not a historical run of good weather in the past.


Why would this be true?

It's not impossible, just location dependent. In some places, there actually is a clear cycle, where the weather alternates between good and bad on a weekly cycle. The Bay Area of California, where HN is headquartered, seems to be one of those places:

The Fog Cycle

Week by week from spring into August, the forces that produce the fog increase in intensity. The Pacific High moves farther north, closer to the latitude of San Francisco, sending out stronger winds; offshore the up-welling of cold bottom waters increases, condensing the winds’ moisture into thicker masses of fog; in the Central Valley, the northward-moving sun sends temperatures to the 100 degree mark and beyond. The hot air rises, sucking cool masses in great drafts through the only break in the Valley’s surrounding mountains, San Francisco Bay. With the ocean air comes the fog, evaporating gradually in the hot, dry air of the Valley, but sometimes penetrating at night as far as Sacramento and Stockton.

The fog seems to come and go in cycles. Until recent years, the conventional explanation for the fog’s behavior was a simple one: as the cool, fog-bearing ocean air is pulled over the coastal hills and across the Bay toward the hot Central Valley (that is, from a high-pressure to a low-pressure area), the nearest parts of the Valley begin to cool off after a few days, much as a draft from an open door lowers the temperature in a warm room.

The incoming cool, heavy sea air replaces the warm, rising land air, and temperatures in Sacramento and Stockton may drop from well above 100 degrees to the “cool” 90s. When the Valley cools sufficiently, the fog-producing machinery breaks down. Without the intense Valley heat to draw the sea air in through the Bay Region, the wind diminishes and no longer carries the fog inland. San Francisco, the Golden Gate, and the coastline are fog free.

Then the process starts all over again. Without the incoming wind and fog, the sun gradually reheats the Valley. The rising warm air again begins to attract the foggy marine air inland. The result is a fog cycle of about a week in length, producing roughly three or four days of fog over the Bay and three or four days of sun.

https://baynature.org/article/cutting-through-the-fog/


Today's weather affect's tomorrows. They are not independent variables.


Weather poses an additional problem in that it is not fully observable. It is only partially sampled and contains unknown unknowns still.


Or you're more likely to be in an area with a pleasant climate




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