4e fighting during a storm

[Jose]

So my players will soon be seeing action during a mild storm. Its going to be a category one storm.

Are there rules for doing things during a storm? Shooting, running and even flying.

[Stormcrow]

I don't know if there have ever been any kind of official rules for this. I would just apply general task difficulty modifiers.

[mlangsdorf]

Storms are dark, so a -2 or so darkness penalty is appropriate. Heavy rain is distracting, so I'd give a -1 penalty to DX and Per rolls unless you're in sealed armor or equivalent. High winds make ranged attacks difficult, so double the effective range for calculating range penalties. Anyone fighting outdoors on the ground has to worry about mud, which gives bad footing (another -2 to DX rolls without the appropriate perks).

Muscle powered winged flight is probably difficult: double movement costs or add some arbitrary water weight extra encumbrance. Machine flight may or may not be affected: WWI biplanes might have issues, modern jets won't care.

Some or all of the penalties can be negated by perks. A TL11 contragrav battlesuit commando might not care, while realistic TL2 archers might be so heavily penalized as to make fighting pointless.

[Celjabba]

Originally Posted by Stormcrow

I don't know if there have ever been any kind of official rules for this. I would just apply general task difficulty modifiers.

First place to check would be Fantasy, iirc there are rules for environmental troubles. On my phone now, I will have a look later.

[Bruno]

Difficulties depend on the storm severity and what you're doing. We have thunderbursts here which are monsoon-severity storms that last <30 minutes, we have storms that approach hurricane intensity briefly, and (small) tornadoes. They're all worse than just "lashing rain".

Cloud intensity makes it dark of course (-1 or -2 sounds right, I'd even go -3 for some of the really epic storms I've been in).

The rain itself imposes a visibility penalty because it's literally between you and what you're looking at - the weather office talks about visibility when describing the severity of a storm up here, and for good reason. Light rain might be no more than an extra -1:4 on speed/range penalties, while monsoon-level rain is easily quadrupled. In snowstorms, it's even worse, with visibility potentially being reduced to barely more than arm's length. Under the most severe conditions giving up to a -5 penalty per yard of distance is defensible.

Bullets aren't going to be significantly deflected by wind and rain over the usual engagement distances - most gun battles play out in the ~20 yard range (sniping is another beast entirely). Arrows and thrown weapons, on the other claw, may be impossible. Getting a bow wet is dreadful for it, but arrows are easily knocked astray by heavy water or wind. I wouldn't have high hopes for lighter thrown weapons like darts and daggers either. Spears are heavier, but suffer the same problem as arrows: long and slim and easily knocked off course.

Effects on footing depend on local terrain. Wet tiles are misery, as with wet smooth stones - I'd go as far as DX checks to stay upright, with a penalty equal to the distance moved, on glazed tiles if you're in dress shoes or thin mud's gotten on them (same with slush - it's like grease).
Sand and soft earth quickly turn to mud, while hard earth leads to sudden flooding - -2 for bad footing for water up to ankle deep and your average "slogging" mud, reduced movement and bigger penalties for deeper slop.

Freezing rain is the worst - everything ends up coated in super smooth super slick wet ice, you're wet to the bone, you're encased in ice (picking up Encumbrance rapidly from the water and ice in your clothes), it just sucks. Try to grab onto something to stabilize yourself and surprise! It's covered in slick wet ice too! :P

[evileeyore]

Originally Posted by Bruno

...(picking up Encumbrance rapidly from the water and ice in your clothes)...

Even without the freezing part, all cloth based gear in rain should rapidly double in weight, thus increasing Encumbrance (sucks for the Padded Clothe wearers)

[weby]

Well, the only rules I can directly recall are:
The example task difficulty in B345 makes things in blizzard -4 harder than things without it when it comes to driving.
Dungeon fantasy suggests -1 for each modifier in the description.
The genral modifiers for combat(B548) have things for distractions and darkness/concealment.

[Anthony]

Originally Posted by Bruno

Light rain might be no more than an extra -1:4 on speed/range penalties, while monsoon-level rain is easily quadrupled.

Most obscurement should actually be a flat penalty per X distance, as the decay is exponential (with the way visibility is defined for weather, you can determine contrast at any given range by multiplying the contrast in perfect visibility by e^(-3 * distance / visibility); this works out to a 95% loss at distance equal to visibility). Based on other rules, I would set the distance for a -1 penalty equal to 1/4 of the standard visibility.

[lvalero]

Survival could be used to negate some penalties. For example an experimented outdorsman could use to his benefit the high and changing winds of the storm lowering the penalties of low visibility.

[Jose]

Where the players are its not necesarily raining. Its a weird planet. All in all it doesn't seem to be all that high penalties with most of them seeming to be from the dark rather than actually the wind itself.

Mind you my players are in a UT environment with guns and lasers rather than bows and throwing weapons. So it seems like at best a -2 or -3 for the characters and thats it. Any ideas what to do with movement?