Everyone has heard weather wisdom that sounds convincing. Some of it is partly true, some is simply wrong, and a few beliefs can lead to a spoiled trip or even danger. Here are eight worth knowing about before you travel.
Myth 1: "A 30% chance of rain means it will rain 30% of the time"
What is true: rain probability tells you the chance that measurable rain falls at your location at some point during the period. A 30% chance could mean one short shower, or a 30% chance of a heavy thunderstorm. It says nothing about duration or amount.
For planning, look at the expected amount in millimetres and the hourly timing. A day with a high probability of a brief light shower can still be a good day out. Our guide on reading forecasts explains more.
Myth 2: "You can't get sunburned when it's cloudy or cool"
What is true: sunburn is caused by ultraviolet radiation, which depends on how high the sun is, not on temperature. Much of it passes through thin or broken cloud. A breezy 16 °C day in May in the mountains, or a hazy summer day on the beach, can burn unprotected skin surprisingly quickly. See the UV index explained.
Myth 3: "Southern Europe is always sunny"
What is true: the Mediterranean has dry, sunny summers, but winter is its rainy season. Rome, Athens and Barcelona get most of their annual rain between October and March, and autumn can bring intense downpours, particularly along the Spanish east coast, in southern France and in Italy.
Winter in the south is still much brighter than in the north, with more hours of daylight and many sunny days. But a winter week in Sicily or Mallorca can be mixed. For the most reliable warmth, look at the Canary Islands, Madeira and Cyprus, and check the forecast before booking. See warmest cities in winter.
Myth 4: "Weather forecasts are always wrong"
What is true: forecasts for the next two days are right most of the time for temperature and generally for whether it will be dry or wet. We remember the misses, such as the shower that arrived two hours earlier than forecast, and forget hundreds of correct forecasts.
Where the myth has a point is far ahead: a specific icon ten days out is not much better than the seasonal average. The skill lies in knowing how far to trust each day. See how reliable forecasts are.
Myth 5: "Lightning never strikes the same place twice"
What is true: lightning often strikes the same place repeatedly, especially tall, exposed objects. Tall towers and buildings are struck many times a year.
What matters more for travellers is lightning safety. On hikes, beaches and water:
- If you hear thunder, you are within striking distance. Move off ridges, summits, beaches and open water.
- Take shelter in a solid building or a car with a metal roof, not under an isolated tree.
- Wait about 30 minutes after the last thunder before going back out.
In summer, thunderstorms in the mountains usually build in the afternoon. Starting hikes early is the most effective precaution.
Myth 6: "Red sky at night, shepherd's delight"
What is true: this one has a grain of truth in western Europe, where weather typically moves from west to east. A red sky at sunset means the sun is shining through clear air to the west, where tomorrow's weather comes from. A red sky in the morning means the clear air has moved east and cloud may be approaching from the west.
But it is a rule of thumb, not a forecast. It works poorly in other weather patterns and should never replace a real forecast.
Myth 7: "The temperature in the app is what it will feel like"
What is true: forecast temperatures refer to air in the shade, about two metres above ground. In direct sun, out of the wind, it can feel much warmer. With wind, near cold water or in damp air, it can feel colder. A 20 °C day can feel like 25 °C in a sheltered sunny square and like 14 °C on a windy pier.
The "feels like" temperature and the wind forecast give a better idea. On coasts, sheltered bays and the leeward side of headlands are often much more pleasant.
Myth 8: "It's cooler in the mountains, so it's safer"
What is true: mountains are cooler, but they bring their own risks. UV radiation is stronger at altitude, weather changes quickly, afternoon thunderstorms are common in summer, and the temperature on a summit can be 10–15 °C lower than in the valley, with wind making it feel colder still.
Check a mountain forecast rather than the forecast for the nearest town, take a warm layer and waterproof even on sunny days, and turn back if storms build.
The common thread
Most weather myths come from simplifying something complicated. The antidote is simple: look at a few more numbers (amount, timing, sunshine hours, wind, UV) and consider how far ahead you are looking. That is all it takes to make weather-led travel decisions with confidence.