Important Links
Examples of Weather Tables can be found
here
Credit and a more full explanation:
Mind Storm Press
Determining Weather
Keep track of your current position on the table.
Every day, roll 2 d8s - one blue, one red - and take the lower of the two rolls.
If the lower is Blue, add its result to the current position; if Red, subtract its result from the current position.
If the current position goes above 15, reset to the row with 'Blue' in the Reset colum (most often 12).
If the current position goes below 1, reset to the row with 'Red' in the Reset colum (most often 4).
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