Input up to 4 MesoWest station IDs to plot each time series on
the same graph.
Requires at least 2 stations. (You can cheat the system
for a single station time series by requesting the same ID twice).
Fill station input in order (i.e. Don't leave Station 2 blank if 1 and 3 are filled).
Input the UTC dates in the format YYYY-MM-DD HH:MM.
If you leave the end date blank, it will use the current time (hard coded to be +7 hours of local time).
Choose the units (only for temperature).
Select the variable.
Note: If the requested station was not plotted, there was an error getting
it's data from the MesoWest API. The station ID may be incorrect
or not availalbe for the request variable or time.
