(see http://www.ageod-forum.com/showthread.php?t=21844)
I was preparing a series of images showing the various weather areas in WIA.
For some strange reason, I couldn't get the coastal areas to display (highlighted as snow, everywhere else being fair).
Digging deeper, this is what I discovered:
In the WIA/GameData/Weathers folder, the coastal areas are named as:
WeatherPatterns_CoastalWaters_Carribean.ini
WeatherPatterns_CoastalWaters_Middle_States.ini
WeatherPatterns_CoastalWaters_Southeast.ini
Inside the WIA/GameData/Weathers/WeatherPatterns_CoastalWaters_Middle_States.ini file, we see the following:
CoastalWaters_Middle_States|January|Other|Fair|0
CoastalWaters_Middle_States|January|Other|Mud|90
CoastalWaters_Middle_States|January|Other|Snow|10
CoastalWaters_Middle_States|January|Other|Frozen|0
CoastalWaters_Middle_States|January|Other|Blizzard|0
CoastalWaters_Middle_States|January|Swamp|Fair|0
CoastalWaters_Middle_States|January|Swamp|Mud|100
CoastalWaters_Middle_States|January|Swamp|Snow|0
CoastalWaters_Middle_States|January|Swamp|Frozen|0
CoastalWaters_Middle_States|January|Swamp|Blizzard|0
CoastalWaters_Middle_States|January|Wilderness|Fair|0
CoastalWaters_Middle_States|January|Wilderness|Mud|40
CoastalWaters_Middle_States|January|Wilderness|Snow|60
CoastalWaters_Middle_States|January|Wilderness|Frozen|0
CoastalWaters_Middle_States|January|Wilderness|Blizzard|0
CoastalWaters_Middle_States|January|Mountain|Fair|0
CoastalWaters_Middle_States|January|Mountain|Mud|30
CoastalWaters_Middle_States|January|Mountain|Snow|60
CoastalWaters_Middle_States|January|Mountain|Frozen|5
CoastalWaters_Middle_States|January|Mountain|Blizzard|5
CoastalWaters_Middle_States|January|FreezeShallow|Fair|0
CoastalWaters_Middle_States|January|FreezeShallow|Mud|0
CoastalWaters_Middle_States|January|FreezeShallow|Snow|20
CoastalWaters_Middle_States|January|FreezeShallow|Frozen|70
CoastalWaters_Middle_States|January|FreezeShallow|Blizzard|10
CoastalWaters_Middle_States|January|NoFreezeShallow|Fair|50
CoastalWaters_Middle_States|January|NoFreezeShallow|Mud|0
CoastalWaters_Middle_States|January|NoFreezeShallow|Snow|30
CoastalWaters_Middle_States|January|NoFreezeShallow|Frozen|0
CoastalWaters_Middle_States|January|NoFreezeShallow|Blizzard|20
CoastalWaters_Middle_States|January|CoastalWaters|Fair|10
CoastalWaters_Middle_States|January|CoastalWaters|Mud|30
CoastalWaters_Middle_States|January|CoastalWaters|Snow|30
CoastalWaters_Middle_States|January|CoastalWaters|Frozen|0
CoastalWaters_Middle_States|January|CoastalWaters|Blizzard|30
CoastalWaters_Middle_States|January|FreezeOcean|Fair|0
CoastalWaters_Middle_States|January|FreezeOcean|Mud|0
CoastalWaters_Middle_States|January|FreezeOcean|Snow|10
CoastalWaters_Middle_States|January|FreezeOcean|Frozen|60
CoastalWaters_Middle_States|January|FreezeOcean|Blizzard|30
CoastalWaters_Middle_States|January|NoFreezeOcean|Fair|20
CoastalWaters_Middle_States|January|NoFreezeOcean|Mud|30
CoastalWaters_Middle_States|January|NoFreezeOcean|Snow|40
CoastalWaters_Middle_States|January|NoFreezeOcean|Frozen|0
CoastalWaters_Middle_States|January|NoFreezeOcean|Blizzard|10
However, in the WIA/GameData/Weathers/WeatherAreas.ini file, rather than "CoastalWaters", we have instead "Coastal":
$area_Weather_Canadian_Maritimes
$area_Weather_Eastern_Canada
$area_Weather_Western_Canada
$area_Weather_Western_Great_Lakes
$area_Weather_Eastern_Great_Lakes
$area_Weather_Upper_New_England
$area_Weather_Lower_New_England
$area_Weather_Upland_Middle_States
$area_Weather_Coastal_Middle_States
$area_Weather_Coastal_Southeast
$area_Weather_Coastal_Carribean
$area_Weather_Upper_West
$area_Weather_Northern_Plains
$area_Weather_Southern_Plains
$area_Weather_Lower_Louisianne
$area_Weather_Upland_South
$area_Weather_Kentuckee_Uplands
$area_Weather_Upland_Southeast
$area_Weather_WxAtlantic
$area_Weather_WxEurope
Furthermore, in the WIA/GameData/Areas.ini file, we also have just "Coastal":
// Area #86, Coastal_Middle_States
UID = $area_Weather_Coastal_Middle_States
Name = Coastal_Middle_States
// Area #87, Coastal_Southeast
UID = $area_Weather_Coastal_Southeast
Name = Coastal_Southeast
// Area #88, Coastal_Carribean
UID = $area_Weather_Coastal_Carribean
Name = Coastal_Carribean
Because of the "Coastal" in the WeatherAreas.ini & Areas.ini files not matching the "CoastalWaters" in the area weather .ini files (in both their name and contents), for all coastal regions in WIA, the weather is always fair!

You can see this for yourself. As I just did, load up your favorite WIA scenario, and cycle through an entire year of turns (hitting the Next Turn button). Check regions within Delaware, or any region in any of the Coastal_Middle_States, Coastal_Southeast, or Coastal_Carribean areas. The weather is never rain/mud, snow, etc., rather always fair!

I think that the fix for this bug is to designate "Coastal" (never "CoastalWaters") everywhere. That entails renaming all the WIA/GameData/Weathers files for example:
WeatherPatterns_CoastalWaters_Middle_States.ini -> WeatherPatterns_Coastal_Middle_States.ini
Also, changing the contents of the coastal area .ini files like so:
CoastalWaters_Middle_States|January|CoastalWaters|Fair|10
CoastalWaters_Middle_States|January|CoastalWaters|Mud|30
CoastalWaters_Middle_States|January|CoastalWaters|Snow|30
CoastalWaters_Middle_States|January|CoastalWaters|Frozen|0
CoastalWaters_Middle_States|January|CoastalWaters|Blizzard|30
should instead be:
Coastal_Middle_States|January|Coastal|Fair|10
Coastal_Middle_States|January|Coastal|Mud|30
Coastal_Middle_States|January|Coastal|Snow|30
Coastal_Middle_States|January|Coastal|Frozen|0
Coastal_Middle_States|January|Coastal|Blizzard|30
(Make those substitutions globally, throughout the coastal .ini files.)
I tested these changes, and -- voila! -- suddenly Delaware (and other coastal regions) started having real, variable weather (rain, snow, etc., in addition to fair).

In all the time that WIA was under development and testing, in all the time since WIA was released, over all the WIA games ever played -- nobody noticed that the weather in Delaware and other coastal areas to the south and southwest is always the same, always fair?
