Test the report
Weather intelligence for trip dates

Pick dates. See what the weather really did.

We read 10 years of airport weather records for your exact dates — about 17,000 instrument observations a year — and turn them into plain probabilities: “rain fell in 4 years out of 10”. Not “40% chance”.

10 yearsof real observations
8 hoursof every day, sliced
2 sourcescross-checked to 0.4°
WEATHER PASS · 10 YEARS

Test mode — free while WhenToGo is in development. No sign-up, no card.

Why averages lie

Same dates. Same city. Two different trips.

April 1–5 in Athens, ten-year average: 16.9° by day. Sounds settled. Here is what actually happened:

APRIL 1–5, 2024
22.4°

Five dry days in a row. T-shirt weather, sunscreen before noon.

APRIL 1–5, 2020
12.9°

62 mm of rain across the window. Jacket, umbrella, museum days.

The average says 16.9°. Neither year looked anything like it. That spread is exactly what our reports show — year by year.

How it works

Three steps, no magic

01 Pick a city and dates

Athens is live in test mode. 50 European cities are being prepared next.

02 We read 10 years of records

Half-hourly airport observations plus the ERA5 climate archive, cross-checked against each other.

03 You see the odds, not a guess

Probabilities as “N years out of 10”, typical ranges, records — and every single year on one screen.

Inside the report

Built for a decision, not a headline

Your day, hour by hour

Eight slices of every day — 07:00 to 04:00 local — with typical and extreme temperature at each hour, and how it actually feels.

Probabilities you can read

Rain, heat, cold nights, strong gusts, thunderstorms — each as “N years out of 10” with dots you can count.

Every year, side by side

The table averages hide: all ten years with day/night temperature, rain, gusts and phenomena. Best and roughest year flagged.

What if you shift the dates?

A week earlier and a week later, compared: warmer or cooler, drier or wetter — sometimes seven days change the whole trip.

When it got wild

Thunderstorms, hail, squalls, snow — every severe event on your dates in ten years, with the year attached.

A verdict in one line

“Days around 17°, pack an umbrella, chilly after sunset.” Generated from the numbers, not from vibes.

Free with every city

The climate passport of a place

Beyond the dates: what the place itself is like. Relief and altitude, seismicity in plain words, sunshine through the year — free, for every city we cover.

Athens: hilly, ringed by 400 m ridges 5 km to the Saronic Gulf Seismically active — explained calmly July: 99% sunny days

Open the Athens passport

Honest data

Where the numbers come from

Two independent sources, cross-checked: instrument observations from the airport (Iowa Environmental Mesonet archive) and the ERA5 climate reanalysis by Copernicus C3S/ECMWF, used under CC-BY 4.0. For Athens they diverge by at most 0.4° on daily highs — we checked, day by day.

Every report says which station it uses and how far it sits from the centre. And everything here is historical statistics, not a forecast — we show the odds, you make the call.

Athens is live — in test mode

Build a report for any dates, free, while WhenToGo is in development. No sign-up, no card. 50 European cities are next in line.

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