Fire weather graphics bug in Meriphataud Mountains [s]

[Mirage]

Whenever there is fire weather in Meriphataud Mountains (S), the weather effect looks very glitchy. The weather effect is making the environment flicker a lot, while fire weather in other zones appears normal. Here are some screenshots to illustrate the issue:

Image 1
Image 2
Image 3
Image 4
Image 5

These five screenshots were taken within 2 seconds, but the flickering occured even faster than that. I would think the distorted effects moved around the game screen more than 10 times per second, making it pretty annoying to look at.

This does not happen in all zones with fire weather. I have noticed it in Meriphataud (S) and in one zone in the present, but I don't remember which one it was. Several other zones display the fire weather effects normally.

System information:
Operating system: Windows 7 64bit
Video card: nVidia GTX460 1GB
Processor: Intel Core 2 Quad 9450
Internet connection: Fiber optical cable, 40/40 Mbit
Internet provider: NTE
Time and date: Several. Most recently at 14:50 GMT+2, September 27th.
Frequency: Every time there is fire weather in Meriphataud (S)
Character name: Fazira
Job and level: Several. Most recently 99DNC/49BLM
World: Sylph
Zone and position: Meriphataud Mountains (S), anywhere in zone. Screenshots were taken at G-7.
Party or solo: Any. Most recent occurence: Solo.
Monster: Not appliciable

Steps:

1. Enter meriphataud mountains in fire weather, with weather effects turned on.
2. Observe glitchy effects

Additional information:
My display drivers were updated last week, but this glitch has occured both with my old drivers and the most recent drivers, so I do not believe it is an issue related to outdated drivers.

A friend of mine has told me that he did experience the same visual distortions on his computer. He is running Windows 7 as well, using a nVidia GTX 560 Ti.