# Background Information for Homework 5: Surface Weather Map Analysis

## Summer 2004

#### BACKGROUND

This homework contains several parts (separated to reduce potential problems with printing large pdf files). This document helps guide you in finishing the assignment.

• Download Homework 5, which contains a set of questions to be answered before and after you have analyzed the weather map.
• Download 100map01.gif, a genuine plotted weather map.  Since this weather map has data plotted in a standard station model, you will need to decode this model (see below).  You will attempt to decode the observed weather data for Madison in south central Wisconsin, answering the appropriate questions on the Homework sheet.
• Download 100map02.gif, a map containing plotted decoded pressure values, plus a partially completed isobar analysis provided as a help in your analysis.  Complete the isobar analysis for practice on this second map.
• Transfer the isobar analysis to the first map and then make an isotherm analysis on the first map.
• Complete the answers to the rest of the questions on the Homework sheet. Then complete your frontal analysis on the first map.

#### STATION MODEL

At each station the following abbreviated surface station model has been utilized:

Wind arrows fly with the wind.

Each full barb equals 10 knot wind speed.

[Sample station reports a 15 knot wind from the southeast (SE)].

Missing values are indicated by an "M".

Note the pressure appearing on this station model is in tenths of a millibar with the decimal and the leading 9 or 10 removed to save space. (Compare the data plotted on the station model with that for on the other map that contains the decoded pressure values.)
A nice tutorial for learning how to decode station models can be found at http://cimss.ssec.wisc.edu/wxwise/station/page5.html

#### CONTOURING or ISOPLETHING

A nice tutorial for learning how to draw isobars is found at
http://cimss.ssec.wisc.edu/wxwise/contour/contour1.html

Latest revision: 27 July 2004 (0205 UTC)

Produced by Edward J. Hopkins, Ph.D.
Department of Atmospheric and Oceanic Sciences