1. Name______________________ Date_____________
Contour Analysis Lab
Name______________________ Date_____________
GENERAL RULES OF CONTOURING:
The more contouring you do the better you will be at interpreting weather maps. In lab session you will be doing contouring on paper weather maps using a pencil. A few guidelines to remember when doing the lab exercises:
1) Prepare to contour
A. Search for continuity (time and space) on the weather map
B. Eliminate what appears to be faulty, or incorrect, data
C. Locate regions of high and low values to start from
2) Drawing the map
A. Use a pencil !!
B. Draw smooth lines
C. Interpolate between given values to correctly place an isopleth
D. Isopleths cannot touch or cross
E. Isopleths cannot branch or fork
F. Areas of tightly packed contour lines are regions of steep gradients
G. Label the isopleths
Use the following web page to practice your skills:
(use the html5 version of practice apps in the IDEA lab)
Then apply your skills on the 4 maps which follow. Contour pressure with 4mb interval starting at 996mb and temperature at 10 deg intervals starting at 10 deg F..

3. MSLP Chart
Pressure mb (chart-1) (4mb contour interval of Isobars starting at 996mb)

5. Deg F (chart-2) (10 deg contour interval of Isotherms)
Surface Temperature Chart
Deg F (chart-2) (10 deg contour interval of Isotherms)

7. {if P < 1000 mb 970 = 997.0mb }{ P> 1000mb then 187 = 1018.7mb}
MSLP Chart
Pressure mb (chart-3) (4mb contour interval of Isobars starting at 996mb)
{if P < 1000 mb = 997.0mb }{ P> 1000mb then 187 = mb}

9. {if P < 1000 mb 970 = 997.0mb }{ P> 1000mb then 187 = 1018.7mb}
MSLP Chart
Pressure mb (chart-4) (4mb contour interval of Isobars starting at 996mb)
{if P < 1000 mb = 997.0mb }{ P> 1000mb then 187 = mb}

11. MSLP Chart
Pressure mb (chart-1) (4mb contour interval of Isobars starting at 996mb)

12. Deg F (chart-2) (10 deg contour interval of Isotherms)
Surface Temperature Chart
Deg F (chart-2) (10 deg contour interval of Isotherms)

13. {if P < 1000 mb 970 = 997.0mb }{ P> 1000mb then 187 = 1018.7mb}
MSLP Chart
Pressure mb (chart-3)
{if P < 1000 mb = 997.0mb }{ P> 1000mb then 187 = mb}

14. {if P < 1000 mb 970 = 997.0mb }{ P> 1000mb then 187 = 1018.7mb}
MSLP Chart
Pressure mb (chart-4)
{if P < 1000 mb = 997.0mb }{ P> 1000mb then 187 = mb}