Weather Sainte-Petronille (Brittany) - Detailed bulletin - DETAILED 15-day WEATHER FORECASTS - METEO CONSULT (2024)

FAQs

How accurate is a 16 day weather forecast? ›

Even now five-day weather forecasts are about 90% accurate, but 10-day forecasts are more like 50%. Anything beyond that becomes speculative. The Met Office and others do now issue long-term forecasts, but these give probabilities rather than making exact predictions.

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The Short Answer: A seven-day forecast can accurately predict the weather about 80 percent of the time and a five-day forecast can accurately predict the weather approximately 90 percent of the time. However, a 10-day—or longer—forecast is only right about half the time.

Unpredictable Changes: The Earth's atmosphere is constantly changing in ways that are simply not always predictable, even in the short term. Some regions, such as the Midwest, have less predictable weather than other areas, such as the West Coast. Weather also often changes faster at high altitudes.

Closer look at percentages

Let's use 60% as the rain chance in the forecast. That means 60% of the entire area (Central Florida) could see measurable rain at some point in the day, while the other 40% won't. That goes beyond the city that you live in.

An assessment from the Post determined that the 45-day forecasts were not even able to predict trends accurately, and that, although the forecasts did not decrease in accuracy with time, the forecasts were so far off even in the short range as to be useless.

The study analyzed 120 million forecasts from over 1,000 locations globally over a four-year period ending December 31, 2018, and AccuWeather was found to be the clear winner as the most accurate provider of weather forecasts in temperature, precipitation and wind speed– a clean sweep of all categories -- for a 1-5 ...

The Weather Channel and 1Weather are also solid options, while Clime NOAA Weather Radar Live and Radarscope are a great way to access more detailed satellite views of the sky. Your stock weather app might be ok for the time being, but it's always worth checking out alternatives on offer.

Is iPhone weather accurate? ›

Even some of the most well-trusted meteorologists can get it wrong sometimes, but it is interesting to observe how different forecasts are to each other. Many people rely on the weather app on their iPhone, but their predictions can be widely different than that of other weather forecasts.

(2) If the forecaster expected a widespread area of precipitation with 100% coverage to approach, but he/she was only 40% certain that it would reach the forecast area, this would, as well, result in a "40% chance of rain" at any given location in the forecast area.

Algorithms don't have that kind of discernment yet, which in turn makes app predictions like precipitation and storms somewhat imprecise. Algorithms also can't compete with the human experience of living somewhere and knowing how weather behaves in that particular area.

1. that 50 percent of the area will get wet. 2. or that it will rain 50 percent of the time. A 50 percent chance of rain means there is a 50 percent chance for any one spot in the forecast area to get wet during the forecast period.

California weather has never been as predictable as a TV weathercaster gag — especially when it comes to the rain and snow of Golden State winters like this one. No state in the lower 48 sees as much variability in its year-to-year precipitation as California.

Midlatitude weather can be predicted with reasonable accuracy for seven to ten days in advance. This was not always the case. The quality of weather forecasts has improved considerably over recent decades. A forecast covering seven days is now as accurate as that for four days 30 years ago.

Unlike the tides and the orbit of planets, the atmospheric system has an intrinsic limit that represents a natural and ultimate boundary beyond which prediction is no longer possible. "Research has repeatedly reached the same conclusions: We can predict the weather up to 14 days in advance at best," said Dr.

10-14 day forecasts are typically reasonably accurate depending on the model and local complications. A climate prediction might be okay past a week. Weather prediction, on the other hand, is not accurate at all past 7 days and is unlikely to improve.