Forecasting the Weather

What is a weather forecast? Forecast: A prediction of weather over the next 3-5 days.

What is a meteorologist? Meteorologist: A person who observes the atmosphere, collects data, and makes predictions—forecasts—based on the data. You know them as weathermen and weatherwomen.

What do meteorologists measure? Air pressure Humidity Precipitation Temperature Wind speed Wind direction

Weather instruments Weather balloon Thermometer Barometer Anemometer

Weather balloons Pictures courtesy of http://www. srh. noaa

Weather Balloons Weather balloons: Carry equipment as high as 30 km above the Earth’s surface Measure temperature, air pressure, relative humidity, wind speed, & direction

Thermometer Thermometer: Used to measure: air temperature

Barometer Barometer: Used to measure air pressure

Anemometer Used to measure wind speed

Wind Sock Used to measure wind direction

Wind Vane/Weather Vane Used to measure wind direction

Radar Used to find location, movement, kind & amount of precipitation

Weather Satellite Orbit the Earth & send information back to Earth; used to track storms, wind speed, humidity, & temperature @ different altitudes

Collecting & Analyzing Weather Data 2 groups who gather information: National Weather Service (NWS) NOAA (National Oceanographic & Atmospheric Administration)

NWS Produce maps based on information gathered from over 1,000 weather stations nationwide

Station Model A small circle that shows the location of a weather station Surrounding the small circle is a set of symbols & numbers that represent weather data

Example of a Station Model

Cold Front Represented by triangles on a line

Warm Front Represented by half-circles on a line:

High Pressure Usually brings clear, sunny weather

Low Pressure Bring rainy weather

Isobars Lines that connect points of equal pressure on a weather map