As with the United States and Europe, forecast skill is typically best where persistence performs worst; in other words, it is easier for weather forecasters to improve upon persistence where the weather varies the most from day to day, given the technology we have to get a good idea about how weather will change.
That said, the best skill in weather forecasts in the entire world in 2022 was found in a strip of land from the Midwest United States northeast to New England and southeast Canada, where some of the most daily variety in the world is found. A small part of southeast South America, mostly in Uruguay and surrounding areas, and a tiny part of Europe around Belgium, also see skill with weather forecasts having improvement of 40% and higher over persistence.
The parts of the world with the lowest forecast skill, unsurprisingly, are found in the tropics, where weather already varies little from day to day and is thus already very predictable. Thus, it’s hard to improve upon that! Northern South America, India, and Southeast Asia see the most widespread areas of low forecast skill.
Most skill is found in temperatures because precipitation is difficult to forecast. However, from the eastern Midwest to New England in the United States, precipitation skill exceeds 30%; the only area in the world with precipitation skill this high and a big reason this is where overall skill is highest in this area.
Thus, if you want weather forecasts that are best relative to what you could forecast yourself assuming the current weather will stay the same, a corridor from near St. Louis northeast to New Brunswick and Quebec in the United States and Canada is the best place to be, even though weather forecasts are still better overall in the tropics. Jamestown, New York shows the best forecast skill in the world.
For a breakdown of forecast skill by high temperature, low temperature, and precipitation, as well as how this skill is calculated, see the full report here.