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:
1 = Dry Moderate
2 = Dry Polar
3 = Dry Tropical
4 = Moist Moderate
5 = Moist Polar
6 = Moist Tropical
7 = Transition
8 = Day is missing
66 = Moist Tropical Plus*
67 = Moist Tropical Double Plus*
Note that for most applications, it is appropriate to consider
MT+ and MT++ (66 and 67) as MT days, as they are a subset of the weather type.
These two subdivisions were developed for the assessment of heat-related
mortality, especially in the Southeastern US, where MT is quite common in the
summer and therefore not terribly useful in segregating days.
As each SSC type is given a different probability of occurring on each day, the .pct file contains the likelihood in percent for each weather type. The first six columns represent the first six weather types above (in order), and sum up to 100 percent. The last two columns represent probability of the day being non-transitional or transitional (TR).