"Weather in wargames" Topic

Lately all my wargaming projects have faced the same problem: how should weather be modelled when game is about action that takes place in area several hundred miles wide and may last several days?

Periods where this matter hit me were carrier battles of 1942 and napoleonic naval. Wind strength, sea state, visibility, clouds etc. are important part of the game. My main concern is that players shouldn't be able to forecast weather too well, but they should have hunch about odds involved. Something like "If we steam westwards whole night, there's good change we find cloud cover to hide us by morning."

To cut it short, what games you think have best weather rules (not just how accurately it models weather, but more like how playable it is)? Is there some specific rules that are your favourite? I don't wont to limit conversation to just the periods I mentioned as equally good solutions can probably be found elsewhere too.

Grande Armee weather rules are very good and have certainly been a major factor in our games.

I use variable visiblity for Arctic Pulp games due to the gusty winds and loose snow.
For long range/long term games, weather should be fairly consistent from day to day with infrequent but significant changes.

Pre plan it- get a weather report for the region for that time of year. You might want to compare 2 or 3 years just to make sure you don't pick the freak one! Remember you might have to divide the map- ground features affect weather, including pacific islands.

Give the players what their metreologists are saying every 6 hours of game time. You can script this or randomise if you are prepared to put in a little more work. Obviously modern forecasts will be more accurate than WW2.

The thing is with weather forcasts especially modern ones is that they are usually accurate, but rely on no changes to the causes- the most noticable effect is that the wind in the upper atmosphere changes speed. If you think the weatherman got it wrong on the forecast, its just that the weather you are getting is actualy late or early!

The forecast you give on Monday 0600 will be mostly reliable for Monday, early tuesday, fairly accurate for Tuesday, Wednesday should be in the right area but may well contain some of Tuesdays weather early on, OR thursdays at night time. The limit of reliable forecasting is 5 days, after that there are too many variables to process.

Damn jumped back to edit and forgot to make clear- As you give each 6 hourly report, it will of course be more accurate for a given time

Mon 0600- expect rain tuesday
1200Rain in the south of the area for most of Tuesday
1800- Rain will start early morning
2359- Rain from approx 0700, to about midday

Here is what I have in my Nap in Egypt rules.

Weather: Weather, of course, will affect the speed of an army on the march. If fighting a historical battle and you know what the weather conditions were that day use them. Or you may use the weather conditions generated by the tables below. This will also work for day to day operations if conducting a campaign.

Unless playing a historical battle roll 1d12 for the season of the year.
1-3 Summer (July, August, September)
4-6 Autumn (October, November, December)
7-9 Winter (January, February, March)
10-12 Spring (April, May, June)

Next roll 2d6 to determine the type of weather for the day.
Summer Autumn Winter Spring
2-8 * 2-7 * 2-3 2-6 * Good
9-10 * 8-9 4 7-10 Gusty Wind
11 10-11 5-7 11 Rain
12 12 8-12 12 Storm

Effects of Weather. Visibility Movement Fire Combat
Good N/A N/A N/A
Gusty Wind ** 15" N/A -1 on die roll
Rain 6" -25% *** -2 on die roll
Storm** 2" -25%/-50%**** As below **, ***

Wind: At the beginning of each game the gamemaster will roll one twelve-sided die (1d-12), to determine the direction the wind will be blowing towards. Note: the wind blows prominently to the South East in this region.

1= NORTH 2= NORTH EAST 3, 4= EAST 5, 6, 7= SOUTH EAST
8, 9= SOUTH 10= SOUTH WEST 11= WEST 12= NORTH WEST

Then roll one eight sided die (1 d-8) once every eight turns/four hours for any changes in the direction of the wind.

Below is the shift in the wind direction.
One or two (1, 2) the wind shifts one position to the left.
Three or four (3, 4) the wind shifts one position to the right. Five (5) the wind shifts two position to the left.
Six (6) the wind shifts two position to the right.
Seven or eight (7, 8) the wind remains the same.

* Heat reduces the march rate 25% for each day with out a river, water well or canal. If units continue for four days non-stop, all movement will have to cease. They may resume the march after a twenty-four hour rest and or a resupply of water.

** Sand/Dust storm roll 1d8 for distance of visibility on the beginning of every turn. For movement, and combat in "Sand/Dust storm" you may use the procedures from "n. Night Operations" below. Units that are facing in to the direction of a Sand/Dust storm will receive a -1 to Shooting Combat and Close Combat.

*** Rain, which will turn the roads to a sea of thick mud and greatly hinder the passage of Infantry Cavalry, Artillery and Beast of Burden (**** -25% on road / -50% off road.) Reduce the march rate 25% for each day it rains (i.e., if it continues for four days non-stop, all movement will have to cease: muskets and cannon would be virtually useless under these conditions). The ground dries out much more quickly, however, at a rate of 50% a day. Rain may change to snow at the higher elevations in the Holy Land.

Regional Conditions:
When you speak of this region most people think of a desert wasteland. But it is far from it.

Egypt; (what is present day Egypt and Northern Sudan).
Climate, desert; hot, dry summers with moderate winters. Primitive road networks.
Terrain, vast desert plateau interrupted by Nile valley and delta. Along the Nile heavy vegetation and many villages. Numerous canales from the Nile River to irrigate the cultivated fields. Within the Nile delta, lush island and swamps. Natural Hazards, Seasonal flooding of the Nile. Fog along the Nile delta in the AM. Periodic droughts, flash floods, hot, driving windstorm called Khamsin occurs in spring, dust storms, and sandstorms. Numerous small villages along the Nile River.

Holy Land; (what is present day Israel, Jordan and Syria).
Climate, temperate; hot and dry in southern and eastern desert areas. Primitive road networks.
Terrain, Negev desert in the south; low coastal plain; central mountains; Jordan Rift Valley.
Natural Hazards, Sandstorms may occur during spring and summer; droughts. Flash floods in Spring. Numerous orchards and cultivated fields, most hill areas covered with rocks and scattered woods.

Thanks for replies all.

Last Hussar, that's a great idea! Pre planned weather could be as detailed as ever needed and because there wouldn't be any randomising in game it would play fast. The problem is that I kinda hoped to get away without an umpire, but that's probably hopeless in these kind of games.

Rolling for weather effects while playing works well if weather can be assumed to be same in the whole area, but this just doesn't always work: for example in battle of Santa Cruz Enterprise was hidden by convenient rain squall, while poor Hornet was attacked just in "adjacent hex".

By the way, is there some good sources about meteorological matters, something you use when making scenarios?

I'm not sure you can not use an umpire in any campaign naval game- you can set up one off battles, but if your talking about long enough for weather changes then its all in the location of fleets, and you need an umpire for that,

If you can't use an umpire try this (thinking on the fly, so rough edge warning! Numbers are for example only)

Weather is on a scale on say 1-10, and is set befor ethe game starts. You have a set of cards which you can shuffle before the game. The backs show the 'long range forcast' A lot worse, worse, deteriorating, continuing, slight inprovement, improving, major improvement. Thats 7 different forcasts. So you make 49 cards- 7 of each (More if you want, but always a multiple of 7)

A card is drawn say every 6 turns, the 1st on turn 6. That means for 6 turns you and your opponent can guess which way the weather will probably go.

On each weather turn you draw the card and enact what it says- The actual system is up to you- it may be a simple instruction (Weather -2), or give a range – (roll d6- 1-2 Weather -2 otherwise -1)

The point is (you've probably guessed) is that what is on the card is GENERALLY related to the forcast on the back. So the ones that say 'A lot worse' would be mostly -2, some on the chance between -1 and -2, and maybe 1 out of 7 just at -1, 'Worse' would have fewer definately -2, and maybe 2 or 3-1, the rest being roll the d6 type (but less than 'A lot Worse', with less chance of getting -2) and so on

No difference would mostly be No change (say 3 cards), with one a 50/50 chance of -1, one a definate -1, and same for +1.

You could either shuffle these up at the start of the game (leading to highly variable weather), or sort into the 7 prediction types at the start, and place into 7 piles.

If you go for the sort method, at the start of the game you place a 'Forcast' counter on the 'No Change' pile- thi swill be the card for turn 6. After it is drawn roll a d6 before turn 7. 1-2 Prediction drops by 1, 3-4 stays the same, 5-6 Improves by one. (so on turn 7 the prediction could be deteriorating, continuing, or slight improvement- place the Forcast marker on the appropriate pile)

After this card is drawn on turn 12, roll again to see if the forcast changes, and so on.

Obviously you could make a forecast for just 2 turns or whatever suits your game- as a I said the numbers are just rough examples.

Do you know, I'm so please with that, I want to make clear it is my Idea, and my IP. You may all use it in personal games though!

Just tought- if you don't like the names use metorolical terms, such as air pressure- "Falling Sharply, falling, Falling slowly, No change, Rising Slowly, Rising, Rising rapidly"!!

Wow!
I'm not yet sure how to implement that to my games, but it certainly got me thinking. I've recently noticed how useful cards can be, although I don't remember any other mechanic that uses both sides of cards.

You can also use Matrix Game arguments. Give the players a weather forecast and the players can use some of their arguments to modify it if they so desire. If they don't modify it, the weather happens as forecast.