Wikipedia:Naming conventions (Seasons)

Use of seasons
Due to the fact that Wikipedia is an encyclopedia read by people throughout the world and not just the Northern Hemisphere I am putting forth a policy that seasons almost never be used to describe the time of an event.

The only exceptions to this should be where the official name of an event includes the season (e.g. Melbourne Spring Racing Carnival) and it should be explained in the opening paragraph exactly what dates are involved. Note: saying that it occurs during spring in Melbourne should not be used since this still is not clear. (Australian temperate seasons start at the beginning of the month not around the 20th); what should be used is "occurs between September and November".

Southern Hemisphere (Whole Month)

 * Summer: December, January, February
 * Autumn: March, April, May
 * Winter: June, July, August
 * Spring: September, October, November

Northern Hemisphere (Whole Month)

 * Summer: June, July, August
 * Autumn/Fall: September, October, November
 * Winter: December, January, February
 * Spring: March, April, May

Note: According to the Wikipedia articles on the seasons they vary a great deal within the Hemispheres eg The unofficial start of summer is a matter of convention: in Ireland it is as early as 1 May, in many countries it is considered to be 1 June, while in others it is as late as 1 July. This is all the more reason to have this policy implemented

Guidelines in changing seasons to dates
While seasonal descriptions should be changed into dates on a case by case basis here are some ideas for alternative descriptions:

Dates
Where ever possible actual dates should be used. Full dates may inhibit readability show simply the month may be used. For example: List of The Office (US) episodes now shows month and year each season (of the show) started and ended, including the days in the title would be cumbersome and is not necessary. | Same page using Seasons

Quarters
Already in use in Wikipedia Quarters, although not aligning with seasons, are a good replacement for them. Even if someone has not used quarters before they are intuitive and their meaning can be easily understood.

January-March = 1st Quarter/First Quarter/Q1

April-June = 2nd Quarter/Second Quarter/Q2

etc.

Theses should be used for tentative release dates of movies/games/tv shows etc where the producer/developer etc has said something like "Coming this Summer" in this case if Summer meant 1 June - 31 August, Third Quarter is a good enough estimate since it has already been stated that "Summer" can differ more than 1 month depending on definition.