Name ____________________________
Period _______
The Never-ending Weather Map Lab
Introduction:
The alarm rings (“ring”), you hit that button you call Old Faithful – a.k.a. the snooze bar. It rings again 10
minutes later, but rather than fight it, you slowly crack open those eyes and think to yourself was it really worth it staying up to
watch Letterman. The fear strikes you. Either you will open your eyes to a beam of sunlight that pierces through the corner of
the blinds hitting you right smack in the face. Or maybe you’ll actually have to peer outside to notice the gloom of another
cloudy winter morning. Either way you are affected. Sometimes that gloom makes you want to jump right back under those
covers, or maybe that sunlight gives you the energy that you need to start your day.
You are used to classifying the weather in one of two ways – good or bad. However, the weather is a much more
complex process. Meteorologists (that’s weather-people to you) use maps of different weather variables to study the weather
and convey their predictions to you via radio or television, or even the Internet. A synoptic weather map is the type of map
that shows past and present conditions of the atmosphere that meteorologists use to forecast the weather.
Objective: You will construct field maps and learn to identify patterns that can be used to predict the weather.
Vocabulary:
isotherm –
cyclone –
barometric pressure –
anticyclone –
isobar –
air mass –
convergence –
source region –
divergence –
front –
Map A – Temperature Patterns
Procedure A:
1. On Map A use a pencil to lightly draw isotherms at a 10-degree interval.
2. Check carefully to be sure that the isotherms are correct, then darken them.
Questions: (Answer in Complete Sentences)
1. What is the general appearance of the isotherms on this map?
2. What is the general relationship between latitude and temperature as indicated by the
data on the map?
3. Between which two cities would there be the greatest temperature gradient?
4. Calculate the temperature gradient between Galveston and Kansas City.
(Write formula and show all work – label properly)
5. Calculate the temperature gradient between Cincinnati and Chicago.
(Write formula and show all work – label properly)
Map B – Barometric Pressure Patterns
Procedure B:
1. On the bottom of Map B convert the following “map symbol” pressures to millibars.
000,040,080,120,160,200,240
For example 000 on the map really equals 1000.0 millibars
2. On Map B use a pencil to lightly draw isobars between points of equal atmospheric pressure using
the pressures given in step 1 of this procedure.
3. Check carefully to be sure that the isobars are correct and then darken.
4. Label the centers of high and low pressure areas using a capital H and L respectively.
Questions(Answer in Complete Sentences)
1. What is the general appearance of isobars on the map with respect to the high and low pressure areas?
2. Which city is the low pressure center located near?
3. Which city is the high pressure center located near?
4. What is the highest pressure on the map (in millibars)?
5. What is the lowest pressure on the map (in millibars)?
6. What change in pressure would be observed along a straight line from Seattle to Salt Lake City?
7. Calculate the pressure gradient between Cincinnati and Minneapolis.
(Write formula and show all work – label properly)
Map C – Surface Wind Patterns
Procedure C:
1. Using Map C, extend the shaft of the wind arrow through each weather station and draw the head to the
arrow to show the direction the wind is blowing towards.
2. Draw larger arrows to show the general pattern of wind flow around the high and low pressure centers.
Questions: (Answer in Complete Sentences)
1. What are the instruments used to measure wind? How are winds named?
2. Name four cities that are experiencing a northwest wind.
3. Name two cities that are experiencing a southwest wind.
4. Describe the general surface wind pattern around the low pressure center.
5. Because of the global winds, toward which direction will the high and low pressure systems plotted on
map B move?
Map D – Precipitation Patterns
Procedure D:
The symbol “R” inside the station model circle indicates rain.
The symbol “F” inside the station model circle indicates fog.
1. Draw a line around the area on Map D enclosing the area where precipitation is occurring.
(Even though fog is condensation, you can choose to include this area because of the fact the
relative humidity would be 100% and the nearby areas could be having some rain – your choice.)
2. Lightly shade in the area where precipitation is probably occurring.
3. On Map D label the location of the continental polar and maritime tropical air masses using the
appropriate symbols.
Questions: (Answer in complete sentences.)
1. Where is the precipitation occurring on the map with respect to the two air masses?
2. How do clouds form over a low pressure center? (Hint: Start with the winds converging…)
3. What do you know about the air temperature and dewpoint in the area you shaded in?
Map E – Synoptic Weather Map
Procedure E:
1. Refer to maps B, C, and D and draw isobars, wind patterns, and the area of precipitation on
map E.
2. Using that information, draw in the cold front and the warm front in the proper locations.
(Hint: Use the air masses, wind direction and temperature readings)
Questions: (Answer in Complete Sentences.)
1. Which pressure center is the precipitation closest to? Why?
2. What is true about the temperature of the air mass behind the cold front?
3. What are the two characteristics used to describe an air mass?
4. What is the source region of the maritime tropical air mass on the map?
5. What is the source region of the continental polar air mass on the map?
Conclusion Questions: (Answer in Complete Sentences.)
1. Describe the general weather conditions associated with a high pressure area in terms of:
a. temperature –
b. surface wind pattern –
c. cloud development –
d. precipitation –
2. Describe the general weather conditions associated with a low pressure area in terms of:
a. temperature –
b. surface wind pattern –
c. cloud development –
d. precipitation –