Extreme Weather

Open the Gravy Mod Menu and go to the Extreme Weather tab. It has:

• buttons: Start Snow, Stop Snow, Send Tsunami, Start Tornado, Stop Tornado, Stop Tsunami, Start Hurricane, Stop Hurricane, Stop All, Start Blizzard, Stop Blizzard, and Lightning Flash (a test strike a few km ahead of you, for any player; its thunder follows after a few seconds);
• live status:
  • the wind at your position;
  • each active event's distance and direction from you, the tsunami's arrival time, and which part of the hurricane you are in;
  • the blizzard's wind and your wheels' grip;
  • Weather Life: rain on the glass (drops and glass parts), whether your craft is in a cloud (moisture and cloud cover), current lightning activity and the last flash, and whether this morning is foggy (with the number of fog banks, the area they cover and the nearest one);
  • the weather sounds playing, and when the next thunder arrives;
• every setting below.

Without the Gravy Mod Menu the mod has no buttons; only the .cfg settings exist.

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Experimental online. This mod runs in multiplayer, but it still has bugs there that aren't fixed yet. It works best in single player for now.

Host only. Only single player or the host can start events; other players don't need the mod.

• As a client the tab shows that the host controls the weather, and the event buttons do nothing (Lightning Flash still works, since it only shows locally). While the game is still connecting, the buttons count as "not the host".
• The game sends the host's weather and turbulence to every player, wherever they are on the map. So while other people are connected to your game:
  • the events leave the shared weather and turbulence alone, and anything they had already changed goes back at once when someone joins. You still get the funnel, eye wall, rain bands, snow, wave, storm light and storm winds yourself (and a blizzard's snow, wind and slippery wheels);
  • to let the events change everyone's weather and turbulence too, turn on Share Weather With Players (Multiplayer section, off by default). A hurricane then gives everyone a steady storm instead of weather that follows your distance from the eye;
  • the tsunami is a visual wave only: it doesn't lift boats, seaplanes or floating objects, so the boats and AI your game simulates don't rise and fall on other players' screens with no wave in sight. Your own craft is still carried and lifted by it.
• What other players see: never the funnels, waves, snowfall or storm clouds (they're drawn only for you), and only the storm sky if you share the weather. Players with the mod see their own Weather Life (rain on the glass, lightning, morning fog) following the shared weather, and hear thunder and rain on the glass; the blizzard, tornado and hurricane sounds only play for the host.
• Storm winds only reach crafts your game simulates: yours and AI crafts you host. Other players' crafts are never touched, but they can see your craft (and AI you host) thrown about by a wind they can't see.
• AI crafts don't count as players. In single player, or hosting with nobody connected, everything works in full.

• Snow only covers the terrain. Buildings, trees, runways and crafts stay snow-free.
• Very distant terrain may keep its normal snow line, because it is drawn with a simplified material.
• Crest only draws the wave within its detailed water area (several km around the camera). Farther away the sea looks flat until the wave comes closer.
• If the game's water is off or Crest's wave shader isn't loaded, the tsunami falls back to a plain moving wave mesh. The BepInEx log says which mode is used. The fallback has no real water, so boats don't float on it; your craft is pushed and lifted instead.
• A tornado's funnel and a hurricane's bands are effects layered over the game's volumetric clouds and can look odd where the two overlap. Parts of a hurricane beyond the camera's view distance are not drawn.
• Storm winds and visuals are not synced to other players. With other players connected they also don't get the storm sky unless you share the weather (see Multiplayer above).
• Rain on the glass: the drops have no real refraction; they are drawn to look like water. Glass is recognised by the game's transparent part material, so modded parts with their own glass shaders get no drops. There are at most 1400 drops at a time; on crafts with a lot of glass, cockpit views put most new drops on the glass near you. If a glass mesh can't be read, it stays dry (the BepInEx log names it).
• Cloud moisture: the game draws its clouds entirely on the graphics card, and their exact shapes can't be read back. Cloud cover, density and the layer's base and top are the game's live values, but in broken cloud the patches the mod wets are its own. They have the right size and amount, but they won't line up exactly with the puffs you see: sometimes you get a little wet in clear air between two puffs, or stay dry in a small puff. With Low cloud quality (no volumetric clouds) there is nothing to fly through, so the glass stays dry.
• Lightning flashes are glows drawn over the clouds, not light inside them. A very distant flash is drawn closer along the same line of sight (keeping its size on screen), so in rare cases it can show in front of a far hill.
• Sunrise is taken as 6:00 until the mod has seen the sun rise during a flight, so with unusual time settings the fog window can be a little early or late.
• Morning fog: valleys are found on a 150 m grid, so gullies narrower than that stay clear. Only terrain the game has loaded counts, so fog appears in new valleys a moment after you fly towards them (they fade in), and banks more than about 16 km away fade out. Far banks are drawn with fewer, larger puffs; within about 6 km they gain detail (a soft cross-fade). At most 7000 puffs are drawn: on Heavy over very foggy country the farthest banks can go without. Fog under a cloud deck is hidden while you fly above the clouds. The banks are soft puffs, not true volumes: they can look a little lumpy at the edges, and when seen from the side while banking hard the top may tilt slightly. Where fog steps up a valley, neighbouring banks can have tops a few metres apart.
• Buildings and cars are not swept away.
• Blizzard: the snow is particles around the camera, so it doesn't pile up on crafts or buildings. In cockpit views flakes fade out within about 2 m of the camera so none show inside the cockpit; if the game's build lacks the particle shader's camera-fade variant, a few flakes may drift through the canopy. The reduced grip applies to the game's wheels and the older resizable wheels; wheels from other mods may keep their grip.
• Weather sounds: the blizzard, tornado and hurricane loops are a few seconds long and repeat. Thunder is one of nine recorded claps and rumbles, chosen by distance. The sounds bypass the game's sound-effect volume (only the master volume applies); use Volume in the Sounds section.

• SimplePlanes 2 0.7.9
• BepInEx 5 (5.4.x, x64 Mono build) installed in the game folder. On Linux/Steam Deck with Proton, add WINEDLLOVERRIDES="winhttp=n,b" %command% to the game's launch options.
• The Gravy Mod Menu for the buttons and live status.

The Gravy Mod Menu is recommended: most mods keep their in-game settings and status there. Without it, edit the .cfg files in BepInEx/config/.