• Redfield• “Whirlwind

Theory”• Rotation• Coriolis

• Espy• Convergence into

Low• PGF• 1841

• Loomis• Rotation AND

Convergence• 1860

Early Maritime Observations (Winds)

Putting it Together (Air Masses)

A First Mention of Fronts

Norwegians Begin to go 3-D

Looking More Like Fronts!

Fronts and Cross-Sections: 1921

Another View

Is the Norwegian Model Still Relevant?

Unified Surface Analysis Manual

Artists don’t get it: Spot the Error!

What’s Wrong with This Picture?

How About This One?

Circled Obs DO NOT Fit CG Pressure Field!

Human-Adjusted Isobars: A Better Fit

The Station Model

You are expected to already know how to read thisPressure in this example is 1024.7mb

Isobars:- The standard contour is simply a quasi-universal starting point for plotting, and is 1000mb- The contour interval is the change in value between isobars. It will be 4mb or less (2mb or 1mb for mesoscale)- Intermediate isobars are drawn in areas of slight pressure gradient and are ½ the value of the general map contour interval- Regular contours are solid lines, intermediates are long dash, nested intermediates are short dash and you may not jump to 1mb intermediates without first using 2mb intervals

Some Standard Surface Symbols

- Frontolysis and frontogenesis will be covered later

- Ignore squall line, ridge, tropical wave: we do not plot the last two and use a different conven-tion for squall lines

- Troughs may be colored brown, purple or black

- Drylines (ignore for now) may be colored brown or orange

Reminders (things you should already know)

• Look over the error sheet when doing your weekly maps and try to avoid those most obvious mistakes

• Front Type is determined by air movement on cold side of boundary

• Front Location is determined by careful analysis of:– Pressure troughs– Wind shifts– Temperature and dewpoint gradients– Cloud and precipitation location– Pressure tendencies

For Those Away at AMS…• Class Policy (please keep these in mind):

– Working together on weekly maps is ENCOURAGED and RECOMMENDED– Working together on weekly quizzes is considered CHEATING, these are

designed to test individual knowledge and progress

• Pre-Test– Print this and individually list the errors (do not work together on this)– Do not include the jumpy nature of the isobars, this is an artifact of the

crappy software I used, but, yes, isobars should be neat and smooth

• Quiz 1– Print this and individually answer the questions and mark the appropriate

maps. Have your glasses ready if needed, the numbers are very small

• Map 1– Print this, preferably on 11x17-inch paper (if available), and analyze:

• Fronts, highs and lows (proper symbols and color)• Isobars (4mb intervals, 1000mb standard contour, label isobars, use regular black pencil)