NAME WEATHER MAPS For decades hundreds of weather stations throughout the United States have been making standard observations of temperature, moisture, air pressure and winds. The data are collected centrally and plotted on maps and charts so that weather patterns may be analyzed. These maps and charts reflect weather differences from one part of the country to another, thus revealing patterns that are important for an understanding of regional weather and for weather forecasting. There are many types of maps and charts showing weather conditions both at the surface and aloft, but surface weather maps are the most widely used and are essential to any study of weather and climate. This exercise is designed to develop your ability to plot and analyze basic weather data and to use surface weather maps. Refer to the Explanation of the Weather Map for the information required to do this exercise. 1. Figure 1 shows the symbols plotted for a particular weather station. Using the symbols on the station model indicate the weather conditions that occur at this particular location. Temperature: Dew Point: Wind Direction: Wind Velocity: % of Sky Covered: Current Pressure: Amount of Pressure Change in Last 3 Hours: Figure 1. Weather station model for location x. Cloud Types: Height of Cloud Base: Weather in the Last 6 Hours: -1-
2. Plot the information given in Table 1 for Cities A, B and C on Figure 2. Table 1. Weather data for cities A, B and C City A City B City C o o o Air temperature 62 F 86 F 32 F o o o Air dew point 60 F 52 F 26 F Air pressure 1022.6 mb 987.4 mb 1042.8 mb Wind direction SW NW Wind magnitude 24 mi/hr Calm 10 mi/hr Cloud Cover 0.8 No clouds 0.5 Present weather Continuous rain Intermittent snow, moderate Figure 2. Templates for plotting weather station data. -2-
3. On the generalized map of the central United States (Figure 3) are plotted the locations of a number of weather stations. The weather data for each of these stations is given in Table 2. On the map a. Plot the temperature, pressure and wind direction for each station using the standard symbols. b. Draw in as accurately as possible the isobars (lines of equal pressure) at 4 mb intervals (1000, 1004, 1008, 1012, etc.) And the cold and warm fronts using the standard symbols. Table 2. Station Weather Data Wind P T Wind Vel. Station (mb) o ( F) Dir. (Mph) Precipitation Abilene, TX 1011 48 NW 22 Bismarck, ND 1012 20 N 20 Light snow flurries Chicago, IL 1003 55 SW 10 Columbus, OH 1012 56 S 11 Des Moines, IA 991 41 NW 12 Heavy showers Detroit, MI 1010 44 E 5 Drizzle rain Escanaba, MI 1009 38 E 12 Drizzle rain Evansville, IN 1006 58 SW 10 Scattered showers Fargo, ND 1009 27 N 23 Light snow flurries Jackson, MS 1013 62 S 10 Scattered showers Kansas City, MO 996 40 NW 14 Laredo, TX 1014 66 S 7 Little Rock, AK 1006 61 SW 11 Memphis, TN 1008 59 SW 10 Milwaukee, WI 1003 45 E 5 Drizzle rain Minneapolis, MN 1003 33 NE 12 North Platte, NE 1007 29 NW 24 Oklahoma City, OK 1006 40 NW 18 Sioux City, IA 1000 36 NW 23 Springfield, IL 1001 56 SW 10 Springfield, MO 1000 56 SW 11 Wichita, KS 1004 35 NW 22-3-
Figure 3. Generalized map of the central United States showing the location of the weather stations listed in Table 2. Plot the weather data for each station on this map, draw isobars at 4 mb intervals (1000, 1004, 1008, etc.) and indicate the location of warm and cold fronts. -4-
c. For each of the following locations - Sioux City, Iowa; Springfield, Missouri and Jackson, Mississippi - write a weather forecast for the next six hours. -5-