1. Forecasting the Weather
Chapter 24.4
Forecasting the Weather

2. Objectives Explain how a weather map is made
Describe the steps involved in preparing a weather forecast.

3. Forecasting the Weather
The World Meteorological Organization was created to promote the rapid exchange of weather information.

4. Station models summarize weather conditions at individual weather observation stations.
Dew point: the temp. at which the air is cooled for it to become saturated with water vapor.

5. Meteorologists use these symbols to indicate weather conditions, wind speed, cloud cover, and wind direction. The inset shows conditions around a weather station. Page 616

6. The wind direction indicated by the symbol labeled “2” is Northerly (0o).
The cloud conditions that are indicated by the symbol labeled “1” is overcast.
Wind speed in #2 is:
Cloud conditions in #2 is:
Wind direction in #1 is:
Wind speed in #1 is:
Isobar: a line on the weather map that connects the points of equal atmospheric pressure.

7. A typical weather map shows isobars, highs and lows, fronts, and precipitation.

8. Types of Forecasts Daily: Weather conditions for a 48 hour period.
Daily extended forecast look ahead five days.
Extended: Long-range forecast that cover monthly and seasonal outlooks.
Usually these are not very accurate at predicting precipitation.

9. Severe Weather Safety Tips
Thunderstorm
Listen to weather updates, stay indoors and avoid water and electrical appliances
Tornado
Find shelter in a basement or room with no windows. Protect head and neck from debris.

10. Safety Cont.
Hurricane
Listen to evacuation routes and stay indoors to be away from flying debris
Blizzard
Listen to weather updates. Dress warmly and avoid walking or driving in icy conditions.

11. Controlling the Weather
Cloud Seeding
Scientist try to produce precipitation by adding freezing nuclei to supercooled clouds.
Hurricanes have not been successfully controlled by using cloud seeding.