Where our climate figures come from, what each number means, and the one rule that matters most: these are long-run averages, not a forecast for your dates.
Last updated: June 2026
Every figure on the site is drawn from the free Open-Meteo Historical Weather API, which serves the ECMWF ERA5 reanalysis. ERA5 is a respected scientific dataset that reconstructs past weather worldwide by blending recorded observations with a consistent physical model, producing a continuous gridded record rather than the patchy coverage of individual weather stations. For each destination we read daily values at that place's exact coordinates, so the numbers describe the spot you actually plan to visit and not a distant airport or regional capital. We read roughly twenty years of records, ending with the last full calendar year and reaching back nineteen years before that.
For each destination and month we summarise a small, deliberately simple set of statistics: mean, minimum and maximum temperature; sunshine hours per day; wet days per week; and peak wind speed. A few of these are easy to misread, so we are precise about them. The rain column counts wet days, not how much water falls, so a low number tells you the rain is infrequent rather than light. Sunshine is given as hours of bright sun on an average day, not a percentage. Each figure is a long-run monthly average, which is why a single hot week or a freak storm does not move it.
To rank months and destinations we grade those four climate signals — temperature, sunshine, rain days and wind — against the kind of weather you have asked for, then combine them into a single score out of one hundred. The four parts are not weighted equally, and we publish the exact weighting rather than hide it: temperature carries the most weight, sunshine and rain sit at an equal middle weight as each other, and wind carries the least. Our guide "How we score weather" walks through the precise calculation, the thresholds and the difference between the instant quick mode and a live precise check, step by step.
This is the point worth repeating. Everything here is a climatological average built from about two decades of records — a realistic baseline for what a place is usually like in a given month, which is exactly what you need when you are booking months ahead. It is not a weather forecast for your specific dates, and any single trip can still diverge from the long-run norm. We would rather give you an honest picture of the typical than a confident promise we cannot keep, so we describe what the climate has tended to do and leave the day-to-day forecasting to the forecasters.
The scores come straight out of the climate record by a fixed rule that is the same for every destination. No place can pay to rank higher, and the ranking is never adjusted in favour of an advertiser or affiliate; the site is funded by ordinary display advertising and optional affiliate links, not by selling position. If you spot a figure that looks wrong, or want a destination added, the contact page is the best route — corrections and requests genuinely shape what gets built next.