Fill in each of the blanks of the following article with an appropriate word. Will you need your snow boots tomorrow? Should you bring an umbrella? Accurate weather 1 are important for planning our day-to-day activities. Farmers need information to help them plan for the planting and 2 of their crops. Airlines need to know about local weather conditions in order to 3 flights. Weather forecasting helps us to make more informed daily 4 , and may even help keep us out of danger. Modern weather forecasting involves a 5 of computer models, observation, and a knowledge of trends and patterns. Using these methods, reasonably accurate forecasts can be made up to about five days in 6 . Beyond that, detailed forecasts are less useful, since atmospheric conditions such as temperature and wind direction are very complex. Most of the computer models used for forecasting are run by the National Weather Service, which creates forecast models 7 on complex formulas. These models are used by many different weather and news services in 8 daily forecasts. Local weather observers, balloons, satellites, and weather stations also help 9 data for forecasts. You don’t need to have a supercomputer or weather balloon to try your hand at forecasting, though. The most basic weather forecasting consists of simple observation. For example, you can look up at the clouds and try to recognize telltale patterns as people did in the past. High, wispy clouds usually presage good weather. An overcast sky means rain or snow is on the way. Certain weather features seem to be 10 with certain types of weather, at least most of the time.