In the calendar files, next to each date is a numerical representation of the weather type for that day. The number codes are as follows:
10 = Dry Moderate
20 = Dry Polar
30 = Dry Tropical
40 = Moist Moderate
50 = Moist Polar
60 = Moist Tropical
70 = Transition
80 or 00 = Day is missing
If you've used the SSC before, you'll notice the change that all weather types are now two digits. That is because the use of the 'plus' types is now expanded. The most common plus type, and the only one included by default before, was Moist Tropical Plus, which originally was developed for use in Heat Warning Systems, in which for many cities Moist Tropical happened far too often to be useful on its own. The expanded types are now all based on being one standard deviation or more away from the mean for the type based on thermal characteristics. For Dry and Moist Polar, this is one standard deviation below the mean apparent temperature; for Dry and Moist Tropical, one above. There is also an entirely new type, Supertransition, which is based on exceeding one standard deviation above Transition seed criteria. All of these are incremental, thus 61 is Moist Tropical Plus (one standard deviation), and 62 Moist Tropical Double Plus (two standard deviations). So:
Dry Polar: DP+ (21), DP++ (22)...
Dry Tropical: DT+ (31), DT++ (32)...
Moist Polar: MP+ (51), MP++ (52)...
Moist Tropical: DT+ (61), DT++ (62)...
Transition: TR+ (71), TR++ (72)... These do not have upward limits though above 3 standard deviations is rare.
Note that for most applications, it is appropriate to consider
these subsets as part of the main weather type... e.g. 61, 62, etc. can
all be merged into 60.
1 = Dry Moderate
2 = Dry Polar
3 = Dry Tropical
4 = Moist Moderate
5 = Moist Polar
6 = Moist Tropical
7 = Transition
8 or 0 = Day is missing
Only the six weather types and transitions are used, no subsets are shown. The only distinction made is when the likelihood of a given weather type for the period is above 33 percent. In this case,
in the text file, the weather type is preceded by a 1,
in the visual file, the weather type is bolded.
It should be noted that the regime calculation is done over a 7-day period centered on the categorized day.