Weather Guides
Learn how to read and understand weather forecasts like a pro
Understanding weather forecasts
weather forecasts predict atmospheric conditions for a specific location and time. Modern forecasts use complex computer models that analyze current conditions and historical patterns to predict future weather.
How Accurate Are Forecasts?
Forecast accuracy decreases over time:
| Timeframe | Accuracy | Best For |
|---|---|---|
| Today | 90-95% | Immediate planning |
| Tomorrow | 85-90% | Next-day events |
| 3 Days | 80-85% | Short trips |
| 5 Days | 75-80% | General planning |
| 7 Days | 70-75% | Trend awareness |
For important events, check the forecast closer to the date for the most accurate prediction.
Temperature & Feels Like
Actual Temperature
The actual (or ambient) temperature is measured by thermometers in shaded, well-ventilated locations. This is the standard measurement you see in forecasts.
Feels Like Temperature
Also called "apparent temperature," this accounts for how humans perceive temperature based on:
- Humidity: High humidity makes warm temperatures feel hotter because sweat doesn't evaporate as efficiently
- Wind: Wind increases heat loss from skin, making cold temperatures feel colder (wind chill)
- Sun exposure: Direct sunlight can make it feel warmer than the measured temperature
💡 Pro Tip
When planning outdoor activities, pay more attention to the "feels like" temperature than the actual temperature. It better represents what you'll experience.
UV Index Guide
The UV (Ultraviolet) Index measures the strength of sun's UV radiation. Higher values mean greater potential for skin and eye damage.
Minimal risk. No protection needed for most people.
Some risk. Wear sunscreen, hat, and sunglasses.
High risk. Reduce sun exposure during midday hours.
Very high risk. Take extra precautions. Seek shade.
Extreme risk. Avoid sun exposure. Skin burns in minutes.
UV Protection Tips
- Apply SPF 30+ sunscreen 15-30 minutes before going outside
- Reapply sunscreen every 2 hours, or after swimming/sweating
- Wear UV-blocking sunglasses to protect your eyes
- UV rays are strongest between 10 AM and 4 PM
- UV can penetrate clouds - protect yourself even on cloudy days
- Snow, water, and sand reflect UV rays, increasing exposure
Air Quality Index (AQI)
The AQI measures air pollution levels and their health implications. It considers pollutants like PM2.5, PM10, ozone, nitrogen dioxide, and sulfur dioxide.
Air quality is satisfactory. No health risk.
Acceptable. Unusually sensitive people should limit outdoor activity.
Children, elderly, and those with respiratory issues should reduce outdoor exertion.
Everyone may experience health effects. Limit outdoor activity.
Health alert. Everyone should reduce outdoor exertion.
Emergency conditions. Everyone should avoid outdoor activity.
Humidity Explained
Humidity measures the amount of water vapor in the air. It's usually expressed as "relative humidity" - a percentage of how much moisture the air holds compared to its maximum capacity at that temperature.
Humidity Levels
| Level | Range | How It Feels |
|---|---|---|
| Very Dry | 0-30% | Dry skin, static electricity, respiratory discomfort |
| Comfortable | 30-50% | Ideal range for most people |
| Slightly Humid | 50-60% | Still comfortable, slightly sticky |
| Humid | 60-70% | Noticeably muggy, sweating doesn't cool effectively |
| Very Humid | 70%+ | Oppressive, difficult to cool down, fog possible |
Wind Speed & Direction
Wind Direction
Wind direction tells you where the wind is coming FROM, not where it's going. A "north wind" blows from north to south.
Wind Speed Scale (Beaufort Scale)
| Speed (km/h) | Description | Effects |
|---|---|---|
| 0-5 | Calm | Smoke rises vertically |
| 6-11 | Light Air | Smoke drifts, leaves rustle |
| 12-19 | Light Breeze | Wind felt on face, flags flutter |
| 20-28 | Gentle Breeze | Leaves and small twigs move |
| 29-38 | Moderate Breeze | Dust and paper blow, small branches move |
| 39-49 | Fresh Breeze | Small trees sway, whitecaps on water |
| 50-61 | Strong Breeze | Large branches move, umbrellas difficult |
| 62+ | High Wind | Whole trees move, walking difficult |
Precipitation Probability
Precipitation probability (PoP) indicates the chance of measurable precipitation (rain, snow, etc.) at your location during the forecast period.
What the Percentages Mean
- 0-20%: Very unlikely - Don't worry about rain
- 20-40%: Slight chance - Keep an eye on updates
- 40-60%: Chance - Consider bringing an umbrella
- 60-80%: Likely - Plan for rain, bring rain gear
- 80-100%: Very likely - Expect precipitation
💡 Important Note
Precipitation probability doesn't tell you HOW MUCH rain or HOW LONG it will rain. A 90% chance could mean brief showers or all-day rain. Check additional details like expected rainfall amounts.
Atmospheric Pressure
Atmospheric (barometric) pressure is the weight of air above a location. It's measured in hectopascals (hPa) or millibars (mb).
Pressure and Weather
- High Pressure (>1020 hPa): Usually indicates fair, stable weather with clear skies
- Normal Pressure (1013 hPa): Standard atmospheric pressure at sea level
- Low Pressure (<1000 hPa): Often associated with clouds, rain, and stormy weather
Pressure Changes
Rapidly falling pressure often indicates approaching storms. Rising pressure typically means improving weather conditions.
Weather Symbols Guide
Understanding common weather icons and symbols:
Weather Glossary
- Barometric Pressure
- The pressure exerted by the atmosphere at a given point, measured in hPa or mb.
- Dew Point
- The temperature at which air becomes saturated and dew forms. Higher dew points feel more humid.
- Front
- The boundary between two air masses of different temperatures. Cold fronts and warm fronts often bring weather changes.
- Heat Index
- A measure of how hot it feels when humidity is factored in with the actual temperature.
- Precipitation
- Any form of water falling from clouds, including rain, snow, sleet, and hail.
- Relative Humidity
- The amount of water vapor in the air compared to the maximum amount the air could hold at that temperature.
- Visibility
- The greatest distance at which objects can be seen and identified. Affected by fog, rain, snow, and pollution.
- Wind Chill
- A measure of how cold it feels when wind is factored in with the actual temperature.
- Wind Gust
- A brief increase in wind speed, typically lasting less than 20 seconds.
Ready to Check the Weather?
Now that you understand weather data, put your knowledge to use!
Check Weather Now