Weather Questions
Answers to your most common weather questions
1Basic Meteorology
What is atmospheric pressure?
Atmospheric pressure is the force exerted by the atmosphere on objects. Changes in pressure cause weather changes. High pressure typically brings clear weather.
Learn more →What is humidity?
Humidity indicates water vapor content in the air. Relative humidity (RH) is the percentage of water vapor relative to maximum at that temperature.
Learn more →How is wind formed?
Wind is the movement of air from high to low pressure areas, caused by uneven solar heating. Wind speed depends on pressure gradient size.
Learn more →2Forecasting
How is weather forecasting done?
Modern forecasting combines observations, numerical weather prediction (NWP), and meteorologist analysis. Supercomputers process data from stations, satellites, and radars.
Learn more →Why are weather forecasts sometimes inaccurate?
Forecasts are based on models with inherent uncertainty. The atmosphere is a chaotic system where small changes can lead to very different outcomes.
Learn more →What is 'feels like' temperature?
'Feels like' temperature is how your body actually feels temperature, accounting for humidity and wind. It can feel hotter or colder than actual temperature.
Learn more →3Weather Phenomena
Why does it rain?
Rain is part of the water cycle. When moist air rises and cools, water vapor condenses into droplets forming clouds. When droplets get heavy enough, they fall.
Learn more →What is a typhoon/hurricane?
Typhoons (Western Pacific) and hurricanes (Atlantic) are intense tropical cyclones with very low pressure and strong winds. They form over warm ocean waters (>26°C).
Learn more →Why do rainbows appear?
Rainbows occur when sunlight refracts and reflects through raindrops. White light is decomposed into visible spectrum colors, forming a circular arc.
Learn more →4Air Quality
What is AQI?
AQI (Air Quality Index) simplifies multiple pollutants into one number. 0-50 is Good, 51-100 Moderate, >101 is Unhealthy.
Learn more →What's the difference between PM2.5 and PM10?
PM is particulate matter. PM10 ≤10μm (trapped in nose/throat); PM2.5 ≤2.5μm (penetrates lungs and blood). PM2.5 is more harmful.
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