I was bored today and started to create a Excel worksheet that will randomize the weather throughout the BRCS for a whole year.
My requirements:
Allow the DM to view it by Region and Month. (Done)
Provide the temperature in Farenheit or Celsius (Done)
Provide the special days and holidays (in progress)
Randomize the weather for the year (in progess...See below)
Allow the DM to set weather variables, i.e. How often it rains, storms, and the average temperature. (Done but see below)

I decided that the overall weather would remain close enough to use the pre-determined areas of each region for a base. For example:
Anuire
The Southern Coast
The Western Coast
The Heartlands
The Northern Marches
The Eastern Marches
Brechtur
The Western Reaches
The Overlook
The Western Basin States
The Eastern Basin States
Khinasi
The Plains States
The Zhainge Valley
The Drocandragh
The Island States
The Basarji Islands
Rjurik Highlands
The Taelshore
The Northlands
The Wild Lands
Thaele
Vos Lands
PC Lands
NPC Lands
The Feral Lands

I would guess that if the Southern Coast of Anuire is getting a light rain it would cover Diemed, Medoere, Roesone, Aerenwe, and Mieres within the same day. It could be a big rain storm over the whole area or one that is moving through the realms over several hours.

What does the rest of the group think about this?

Steve