Day-To-Day Change Table

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Using the Temperature variation chart:

Roll 2d6 for each day beyond the present one, either day by day as needed or for a number of days in succession if desired. Use two dice that are different in color or size, so that they can be designated ‘die 1’ and ‘die 2’. This distinction is important whenever there is a chance of precipitation, as explained below.

Day-To-Day Change Table

Dice Roll Temp. Change Chance of Precip. Wind Conditions
2
-3 steps
yes
very strong (see Special Weather)
3
-2 steps
no
from arctic, +15 mph
4
-2 steps
yes
from arctic, +10 mph
5
-1 step
no
prevailing direction, +15 mph
6
-1 step
yes
prevailing direction, +10 mph
7
no change
same
same as previous day
8
+1 step
yes
prevailing direction, -10 mph
9
+1 step
no
prevailing direction, -15 mph
10
+2 steps
yes
from tropics, -10 mph
11
+2 steps
no
from tropics, -15 mph
12
+3 steps
yes
very slight (see Special Weather)

Arctic Precipitation Variation
Subarctic Precipitation Variation
Temperate Precipitation Variation
Subtropic Precipitation Variation
Tropic Precipitation Variation

Notes:

Temperature Change:

Move up or down the letter scale as required to ascertain what the next day’s high and low temperatures will be. If the present temperature is within the allowable range (as indicated by the first and third letters of the Temperature code) but a move dictated by this table would take the result beyond that range, then stop when the extreme result is reached.

If the current temperature is already at the upper limit, treat and ‘+’ as ‘no change’, and treat a roll of 7 the same as a roll of 6 – that is, the temperature drops 1 step and precipitation is possible. If the temperature remains at the upper limit for two consecutive days, treat a roll f 7 or 8 as a roll of 6, and continue this pattern until the streak of warm weather ends (for a streak of cold weather, reverse this process.)

Chance of Precipitation

If the dice roll indicates a “yes” result in this column, note the numbers that came up on die 1 and die 2 and consult the Precipitation Variation Table for the appropriate region.

Wind Conditions

On a dice roll of 3 through 11, this column is used to determine the direction and velocity of the wind. Note that a wind from the arctic will be a north wind is the norther hemisphere and a south wind in the southern hemisphere. The reverse is true for a wind from the tropics. The “prevailing direction” is as described in the in the text for the various climatic regions. The velocity increment (+15 mph, +10 mph) is added to the wind velocity for the previous day.

Wind velocity represents the highest speed the wind will reach on the day in question. during gust that can last anywhere from a few seconds to several minutes. For the rest of the day, the wild speed will be no more than half the indicated maximum velocity.

If the dice roll on the Day-to-Day change table is 2 or 12, follow the normal procedure for determining temperature change, chance of precipitation, and the wind conditions, and then refer to the Special Weather to see if some extraordinary weather occurs.

Day-To-Day Change Table

Caelestis Indomitus Tanelornpete

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