Help with a weather situation

[Tahlilian]

Im wanting to have a large fog cloud, say 10-15 miles in size and I want it to last for 2-3 weeks maybe a month. We are play close to "The Evermoors". My problem is how to explain why this is the way it is. Is there a way to use magic or magical items to make this happen or can I just say that's the way it is.

 

[Sekhmet]

If it is winter, you can just claim it is advection fog.
Advection fog is caused by the moist air (above/around the Evermoors) passes along the colder ground (surrounding the boggy area).
There is no real time limit to the amount of time it could potentially take for a thick fog, in the right conditions, to dissipate; which could easily pass into the following morning when the ground cooled again and caused the fog to renew itself.

Alternatively, you could just say it was several Permanent Solid Fog or Fog Cloud spells.

 

[Rhun]

Say someone blew a cursed Horn of Fog, that once sounded continues to pour forth fog. In an attempt to get rid of it, they tossed it into the Evermoors.

Also, if I am not mistaken, moorlands are typically characterized by heavy fog anyway.

 

[krupintupple]

Group of necromancers attempted to cast animate dead on a dragon they found, hoping to gain a powerful ally, but instead all of this darned fog appeared. Turns out it wasn't a red dragon like they thought, but a mist or fog dragon (Draconomicron, I think), and all it really did was annoy its spirit, so it retaliated in one of the few ways it could and blanketed an already foggy coast until it can be appeased or put to rest. This might also allow you to give the fog an extremely faint trace of necromantic magic - which could give an eerie edge to your campaign, and keep the PCs on the toes, and explain why villages are more hesitant or spooked in general.

 

[RUMBLETiGER]

Stronghold Builder's Guide has the Cloudgathering Orb (p.75), Hurricane's Eye (p.78), Orb of Pleasant Breezes (p.81), Tornado's Eye (p.84) and Windstorm's Eye (p.86).

These are all Wondrous Architecture, large crystal orbs that produce permanent weather effects usually in usually a 2 mile radius (4 mile diameter) around the item. each of these items produces a different kind of weather effect. Build a few of these every few miles to overlap the territories, within massive, defensible strongholds so it becomes a quest to go in and smash them if anyone wants to end the effects.

This effect is supposed to be permanent according to the item's descriptions, you can either build in some sort of on/off trigger, or put up an anti-magic zone around the orbs to have them suppressed.

 

[domino]

Don't. You're the GM. Does it matter how, or is it just for (ha) atmosphere?

 

[Ashtagon]

Don't create an explanation. Let the players worry about it if they are interested. They may even figure out an explanation which provides an adventure.

 

[Sekhmet]

Don't. You're the GM. Does it matter how, or is it just for (ha) atmosphere?

Don't create an explanation. Let the players worry about it if they are interested. They may even figure out an explanation which provides an adventure.

While I agree with your central premise, that the GM doesn't always need to have a reason for something other than "I think it would be cool", I think it is best that you have a backup just in case the players really get interested in a phenomenon enough to start asking villagers, seers, or gods.

 

[kitsune9]

Unless the players are interested and want to know, you can state that it's a natural occurrence like Sekhmet states or some form of magic.

For me, I always like a little bit of history and a magical result from a spell, curse, or magic item ends up creating the fog.

 

[Sekhmet]

Unless the players are interested and want to know, you can state that it's a natural occurrence like Sekhmet states or some form of magic.

For me, I always like a little bit of history and a magical result from a spell, curse, or magic item ends up creating the fog.

And then the necromancer I've been playing since 2e (revised and remade for 3.x) is all "Bro, do want", finds it, steals it, and sets it in her own marsh, surrounding her adamantine tower, so she can create a group of semi-sentient, 10HD Fog Wraiths to protect the lands.

BRB, making a new adventure.