LAB: Weather Maps in Motion North Carolina

LAB: Weather Maps in Motion – North Carolina

QUESTION: How do we interpret current weather maps?

MATERIALS: A computer, Internet access

PROCEDURE: A weather map is a map or chart that shows the meteorological conditions over a specific geographic area at a specific time. Meteorologists use weather maps to show patterns in the data to aid in forecasting the weather.

Zulu Time (Z) is one of several names for the 24-hour time that is used throughout the scientific and military communities. Other names for this time measurement are Universal Time Coordinated (UTC) or Greenwich Mean Time (GMT).

0000Z = 12:00am (midnight)

0600Z = 6:00am

1200Z = 12:00pm (noon)

1800Z = 6:00pm

Zulu Time is the time at the Prime Meridian (0º longitude). The time in North Carolina is Z minus 5 hours.

1. Go to:

Use the weather maps to fill in the table below.

Zulu Time / North Carolina Time / Date / Frame Sequence (1st, 2nd, etc.)

0000Z

/ 12:00am / 09-14-2012 / 5th
0300Z / 3:00am / 09-14-2012 / 6th
0600Z / 6:00am / 09-14-2012 / 7th
0900Z / 9:00am / 09-14-2012 / 8th
1200Z / 12:00pm / 09-13-2012 / 1st
1500Z / 3:00pm / 09-13-2012 / 2nd
1800Z / 6:00pm / 09-13-2012 / 3rd
2100Z / 9:00pm / 09-13-2012 / 4th

2. Draw the map symbol and label the cross sections for the fronts below:

(For help, go to:

LABEL / CIRCLE ONE /

DRAW FRONT SYMBOL OR CIRCLE ONE

Front A / Cold Front / Warm Front /
Front B / Cold Front / Warm Front /
Air Mass C / Cold / Cool / Warm / DENSITY: High / Medium / Low
Air Mass D / Cold / Cool / Warm / DENSITY: High / Medium / Low
Air Mass E / Cold / Cool / Warm / DENSITY: High / Medium / Low

3. As a cold front catches up with a warm front, an occluded front forms. What happens to the warm air between the two frontal interfaces? (Circle one.)

A) The warm air is forced under the cold frontal interface but over the warm frontal interface.

B) The warm air is forced over both frontal interfaces.

C) The warm air is forced under both frontal interfaces.

D) The warm air is forced under the cold frontal interface but under the warm frontal interface.

4. Draw the map symbol for an occluded front.

5. Look at the weather map loop. Which is faster? a cold front / a warm front

6. Pick a cold front and estimate its speed in miles per hour. Show your work below. (Hint: America is about 3,000 miles from coast to coast.)

The front we observed moving across the United States traveled approximately 1000 in a 24-hour period. 1000/24 would calculate to a speed of 41.6 miles per hour for the estimated speed of the cold front as it moved across the US.

7. Explain the relationship between the locations of high and low pressure centers and fronts.

High-pressure centers are located in front of, or behind, frontal boundaries. Low-pressure centers tend to form along the frontal boundaries.

8. In what general direction do cold fronts move across America? Warm fronts?

Cold fronts typically travel from the northwest toward the southeast as they move across the US. Warm fronts typically travel from the southwest toward the northeast.

9. How should the weather change (before, during, after) as a cold front passes by? A warm front?

Cold front: Before (warmer); During (windy & stormy); After (clear & colder)

Warm front: Before (cooler); During (drizzly rain); After (clear & warmer)

10. In America, which type of front extends southward from a low-pressure center? Eastward?

In the US, a cold front extends southward from a low-pressure center and a warm front extends eastward from a low-pressure center.

11. Go to:

Find this station in North Carolina on the weather map, and complete the table.

(For help, go to:

Frame Sequence (1st, 2nd, etc.) / Date / Time / Temperature (ºF) / Dewpoint (ºF) / Pressure (mb) / Wind Direction / Wind Speed (kts) / Sky Cover
(% cloudy)
5th / 9/14 /

0000Z

/ 72 / 64 / 233 / NNE / 3-7 / 0
6th / 9/14 / 0300Z / 68 / 65 / 231 / NNE / 3-7 / 0
7th / 9/14 / 0600Z / 67 / 66 / 223 / N / 3-7 / 0
8th / 9/14 / 0900Z / 68 / 66 / 225 / NE / 3-7 / 0
1st / 9/13 / 1200Z / 79 / 68 / 222 / NE / 0 / 0
2nd / 9/13 / 1500Z / 83 / 61 / 246 / NE / 3-7 / 0
3rd / 9/13 / 1800Z / 82 / 64 / 250 / NE / 0 / 0
4th / 9/13 / 2100Z / 76 / 66 / 252 / NE / 0 / 0

12. A meteogram is a graphical depiction of trends in meteorological variables such as temperature, dew point, wind speed and direction, pressure, etc. The time series meteogram can be constructed using observed data or forecast data.

Using the data from the table, complete the meteogram on the next page.

For Temperature, Dew Point, Pressure and Wind Speed, make line graphs.

For Wind Direction, draw a station model in the box showing where the wind is coming from. Examples:

For Sky Cover, draw the proper map symbol in the box. Examples:

(SEE WIND DIRECTION AND SKY COVER ON NEXT PAGE)

Use the information from the North Carolina Station Data Table to record the wind direction and sky cover data below. Example: The wind direction on 9/13 at 12:00zulu was NE and the sky cover was 0%. You need to write the wind direction (such as, NE) in the top box and the % of sky cover in the bottom box below the wind direction for the matching date and time. Be sure to add your date and time information at the bottom of the chart, starting with 12:00zulu on 09/13.