Since I want the seasons to play a part in the game, I've created a table for the GM to use in determing the starting season for a campaign or adventure. Serendipitously I came up with six seasons by splitting the traditional division of two seasons -- wet and dry -- by the state of the winds and the expected events and activities across most of the islands. With six seasons, you can determine your start by rolling a six-sided die.
The southwest monsoon (Habagat) is blowing. Typhoons are drawn from the east and swept north-northwest by the monsoon wind.
Mostly rainy, with strong chance of typhoons. Hot and humid.
Travel and other outdoor activities mostly curtailed. Raiders from the south or west active, but cautious of storms. Emergency repairs to the ricefields after a heavy storm.
The southwest monsoon gives way to the northeast monsoon (Amihan), bringing drier, cooler weather.
The rains finally stop, and the weather cools.
Rice harvest, accompanied by sacrifices, festivities, and often marriages. It’s considered lucky to marry in this season. Raiders from locales that grow little rice, or were badly hit by storms, may attack and try to steal some of the harvest.
The Amihan winds gain in strength, bringing with them traders from the northern lands beyond the Janggalan Isles.
The coolest time of the year. Occasional rains, but mostly dry and sunny, with cool winds. It gets positively cold in the highlands.
Foreign traders call at the largest ports. Vijadesan traders begin sailing out a week or so after, bringing imported goods south and west. Raiders set out to attack southern or western targets.
The height and end of the Amihan monsoon.
Dry, initially cool but quickly growing warmer every week.
Voyaging to the west and south picks up. Height of the deer rut season, and migratory birds from the north are fattest at this time, just before they set out for their nesting territories; much hunting is done now.
The Amihan gives way to the Habagat sometime during summer. At the midpoint of the season there may be little or no wind at all for days.
Very hot, and increasingly humid. Thunderstorms in the afternoon or evening grow more frequent toward summer’s end, heralding the start of the rainy season.
Traders who have gone south prepare to return as soon as the monsoons turn. Early summer is considered excellent time for voyaging.
Farmers prepare the rice fields for planting. Rice is planted as close to the start of the rainy season as the farmers can, but with enough days to grow sturdy enough to take the heavy rainfall.
With good weather and clear waters, this is also the height of pearl diving season in areas that have pearl beds.
The Habagat picks up strength, bringing heavy rains.
Increasingly rainy. Often it rains all day for several days at a time. Hot and humid when the sun is out, cool and humid when it’s been raining.
Traders and raiders from the south make their way north or east. Farmers and their families are busied guarding the crop against wild animals, specially deer and wild boar who relish the young rice shoots.
Now that we’ve a table of the seasons, we can set up rules for using them in play.
Determining Starting Season
Roll a six-sided die and refer to the table. 1 means Storm season, 6 means Rain.
Any voyages in the direction of the prevailing monsoon gains +1-2 Advantage dice. Voyages against the direction of the monson gets you 1-2 Disadvantage dice (that is, they are rolled by your ‘opponent,’ the GM). The later in the season you go, the stronger the effect of the current monsoon.
You take 1-2 Disadvantage dice whenever travelling overland in heavy rain. This will of course occur more often during Rain and Storm seasons.
If caught by a typhoon at sea, you and your crew must ‘fight’ the typhoon to survive. The pilot rolls to save the ship; everyone else rolls to stay aboard and uninjured. Typhoons are typically Threat 4-6, Resistance 3-6.
Every time a pilot loses a roll vs. a typhoon, the ship takes Hull damage equal to the typhoon’s Victory Points, unless the pilot Pushes the roll.
Every Victory Point scored by the pilot vs. the typhoon on the other hand means he’s made progress toward safety. When the typhoon’s Resistance has been expended, the vessel is out of the storm.
Overland travel during a typhoon is simply impossible – driving rains, powerful winds, and flooding make progress in the trackless wilds too difficult and dangerous. If the PCs insist, let them roll vs. the typhoon as with a typhoon at sea. Each loss vs. the typhoon indicates some exhausting or injuring accident has occurred to that PC.
Additional GM Tips
As a GM, you can use the seasons to flavor the game even more. What are the people doing? What are they eating? What are they looking forward to or dreading?
Rice is most plentiful right after the harvest, of course. But most of the Janggalan Isles can’t grow a lot of rice, which prefers low, wet or irrigated ground. Most Vijadesans will have no more rice by summer’s end, or earlier if they were profligate with it, and will be eating mostly yams and taro instead.
Game meat is most plentiful during the Spring hunting season, when the hunters are bringing back venison, wild pork, or gamefowl, specially migratory ducks, almost every day. After this, fresh game meat will be more of an occasional treat.
Though meat animals like chicken, hogs, and buffalo breed all year in the Janggalans, Vijadesans will usually consume domesticated animals only after a sacrifice. Since sacrifices peak at Harvest season, this is also when you can expect meat on the table most often.
Trading and Raiding
The big question here is, will the PCs’ hometown be on the sending or receiving end? Is their hometown prepared to receive the enemy’s visits? Are they sharing your island with anyone who might team up with a raiding fleet from elsewhere?