Finding your way around
1. After you've read the rest of this blurb, use the menu at right to select an area. Check the UTC time that appears on the first screen. It's the time used by all charts to avoid you going crazy with a squillion time zones.
2. A screen like the one below (but without the map) will open. Here's how it works: |
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Firstly, you have three sets of menus to other charts and documents.
Menu 1 lets you jump to another continent or the oceans/poles area, and
Menu 2 lets you jump between high scale areas on the current continent.
Clicking any link in menu 1 or 2 brings up the home page for the new chart.
Menu 3 lets you access help documents and cheat sheets, or go back to AWN's home page or this general chart index page.
Secondly, you have two sets of menus for the charts themselves:
Menu 4 is for hourly charts - 24 charts, one for each of the past 24 hours, and
Menu 5 is for archive charts - 4 or 8 charts for each day for the past month. These are better than the hourly charts because they have much more detail.
Clicking any link in menus 4 or 5 opens that chart in window 6. |
3. When the chart opens (drum roll), the first thing to do is to check the "GENERATED" time/date/month in the top left corner. Make sure you are not looking at an old chart! Check that the GENERATED time/date/month is later than the chart you're expecting. For example, if you are looking for today's 13UTC chart, check the time is after 13:00 and the date is today. The charts become available anywhere from 15 to 50 minutes past the hour, so the new chart may not have been uploaded yet. Also, heaven forbid, things do occasionally go wrong and a chart may not be produced at all.
4. (Nearly there...) The chart will show the familiar pressure lines (isobars) in red, similar lines for temperature (isotherms) in green, and also grey wind streamlines. Most important, though, are the station plots dotted all over the map. These are what make true synoptic charts special. Each plot gives a detailed description of the weather at a weather station in a plot that would fit under a 5c piece. Template 7 is always to the left of the map to remind you how the plot is laid out.
If you're a first time user or need more detailed information, check out this General Chart FAQ & Tutorial.
You may find these reference charts useful: World countries (2.8mb) and World timezones (1.2mb)
If you have any comments on, or suggested improvements to, the maps, I would greatly welcome feedback.
Changes are being made to the World Weather Maps to make them easier to navigate and to provide more information. The charts now show:
- Plots for each station that can be fitted on the chart showing weather information, as before
- Isobars, high and low pressure systems as before
- Isotherms, or lines of equal temperature. These were on the charts previously, however they are now more prominent and at intervals of 5C. They are coloured green, but the 30C isotherm is brown, the 0C isotherm is dark blue and the -30C isotherm is purple. This gives a quick way of finding hot, cold and very cold areas.
- Humidity. Areas of high humidity (>85%) are shaded light green - look in these areas for rain or (if the temperature is below zero) snow. Areas of low humidity (<15%) are shaded light yellow.
- Note that for ocean charts only plots and isobars are shown because of the lack of temperature and humidity observations.
A new user interface is being developed to make the charts easier to access. |
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