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Weather in Kementari

To determine the present or future weather conditions, follow these steps:   1. Find the Base Temperature for the correct month from the “Temperature Ranges” chart. Roll dice as specified to find the adjustments to the Base Temperature for the day’s High and Low. Adjust both the High and Low Temperatures for terrain and for latitude. The High Temperature will occur about one hour after mid-day, and the Low Temperature will occur about one hour before Sunrise. The possibility of temperature extremes may be added by the following;
Before checking for the monthly Base Temperature on the “Temperature Ranges” chart, roll percentile dice and consult this table-  

Temperature Extremes

% Dice RolBase Temperature Modification
01Extreme Record Low
02Severe Record Low
03-04Record Low
05-96Normal Temperature
97-98Record High
99Severe Record High
00Extreme Record High
During a Record High or Low, the Base Temperature is the monthly base Temperature plus or minus the maximum high or low possible for the month. Severe Record Highs or Lows are calculated the same way, only using twice the maximum high or low. Extreme Record Highs or Lows use triple the maximum high or low. Once the new Base Temperature is calculated, then the daily Highs and Lows are calculated normally.
The length of time the Temperature Extreme lasts is determined by the following table-  

Duration of Temperature Extreme

% Dice RollDuration
01-051 day
06-152 days
16-503 days
51-704 days
71-855 days
86-956 days
96-007 days

Temperature Ranges

MonthBase TemperatureDaily HighDaily LowPrecipitationMidmonth SunriseMidmonth Sunset
  Baseline Latitude is 24o. For every 1o North of the baseline:
  • Subtract 1o from Base Temperature.
  • Add 1 minute to Sunrise and Sunset times.
For every 2o South of the baseline:
  • Add 1o from Base Temperature.
  • Subtract 1 minute to Sunrise and Sunset times.
1o Change in Longitude causes a 4 minute change in Sunrise and Sunset times.
Midnight Sun Effects:
  • At 66.5o Latitude;
    • No Sunrise at mid-Winter
    • No Sunset at mid-Summer
  • For every 1o latitude north of 66.5o, add 3 days to the length of time (1 1/2 day before and 1 1/2 day after).

Terrain Effects Table

Terrain TypePrecipitation AdjustmentTemperature AdjustmentWind SpeedSpecial Weather
Hills--+/- 5 mph
  • 01-80: Windstorm
  • 81-00: Earthquake
Forest--5-5 mph
  • 01-80: Quicksand
  • 81-00: Earthquake
Jungle+10%--10 mph
  • 01-60: Rainforest downpour
  • 61-80: Quicksand
  • 81-00: Earthquake
Swamp or Marsh+5%+5-5 mph
  • 01-25: Quicksand
  • 26-80: Sun Shower
  • 81-00: Earthquake
Plains--+5 mph
  • 01-50: Tornado
  • 51-00: Earthquake
Desert-30%+10(day), -10(night)+5 mph
  • 01-25: Flash Flood
  • 26-50: Sandstorm
  • 51-65: Oasis
  • 66-85: Mirage Oasis
  • 86-00: Earthquake
Mountains--3 per 1000 feet elevation+5 mph per 1000 feet elevation
  • 01-20: Windstorm
  • 21-50: Rock Avalanche
  • 51-75: Snow Avalanche
  • 76-00: Earthquake
Seacoast (within 48 mi. of coastline)+5%-5(cold current), +5(warm current)+5 mph
  • 01-80: Earthquake
  • 81-00: Tsunami
At Sea (more than 24 mi. from coastline)+15%-10(cold current), +5(warm current)+10 mph
  • 01-40: Tsunami
  • 41-00: Undersea Earthquake
No Monsoon or Tropical Storm permitted in Plains. No Fog, Mist, Blizzard, Monsoon, Tropical Storm, Gale, or Hurricane permitted in Desert. Duration of Fog and Mist doubled At Sea.   2. Roll percentile dice to determine if precipitation will occur (Temperature Ranges Table). This roll is affected by terrain. If there is no precipitation, roll d20-1 for wind speed and adjust for terrain. Consult the “Wind Chill Table” if necessary.  

Wind Chill Table

Wind Speed (mph)Temperature
  If precipitation will occur, roll on the “Precipitation Occurrence Table”. If a Special Weather Phenomenon is indicated, roll on the “Precipitation Occurrence Table” again to determine the more normal form or precipitation that will be occurring with the special weather phenomena.  

Precipitation Occurrence Table

RollType of WeatherRequired Temp. MinRequired Temp Max.Chance of ContinueChance of RainbowNot Allowed in
01-02Heavy Blizzard-105%-Desert
06-10Heavy Snowstorm-2520%--
11-20Light Snowstorm-3525%1%-
28-30Heavy Fog206025%1%Desert
31-38Light Fog307030%3%-
46-60Light Rainstorm25-45%15%-
61-70Heavy Rainstorm25-30%20%-
85-89Tropical Storm40--20%10%Desert, Plains
90-94Monsoon55-30%5%Desert, Plains
98-99Hurricane or Typhoon55-20%5%Desert
  3. Once the type of precipitation is known, consult the “Standard Weather Table” or the “Special Weather Table” to discover the effects the weather will have on wind speed, visibility, etc. When the duration of the precipitation expires, roll the Chance of Continuing or lower. If the roll is made, roll for the duration of the precipitation again, and consult the following chart:  

Change in Precipitation

d10 rollResult
1Move up one line on the “Precipitation Occurrence Table”
2-9No change
0Move down one line on the “Precipitation Occurrence Table”

Standard Weather Table

WeatherAmount (in.)DurationMovement RateWind SpeedVision Range NormalVision Range InfravisionTrackingChance of Getting LostSpecial Effect
Hvy. Blizzard2d10+103d8 HoursF:/8, H:/4, C:NA6d8+402’0NA+50%Snowdrifts of up to 10’/hour may accumulate
Lt. Blizzard2d8+83d10 hoursAll/43d8+3610’x1/2-40%+35%As Hvy. Blizzard, but at 5’/hour
Heavy Snow2d8+24d6 hoursAll/23d10x1/2x1/2-25%+20%Drifts of 1’/hour if Wind Speed > 20 mph
Light Snowd82d6 hoursF: x3/44d6x3/4x3/4-10%+10%Drifts of 1’/hour if Wind Speed > 20 mph
Sleetd2d6 hoursF: x3/4, H:/2, C:/23d10x3/4x3/4-10%+5%-
Hail-d4 hoursAll x3/44d10---10%+10%Size of stones d4/2. 1 pt dmg/1/2”/turn AC 6 or worse.
Hvy. Fog-d12 hoursAll/4d202’x1/2-60%+50%-
Lt. Fog-2d4 hoursAll/2d10x1/4x3/4-30%+30%-
Mist-2d6 hours-d10---5%--
Drizzle1d10 hours-d20---1%/turn--
Lt. Raind3d12 hours-d20---10%/turn-Temp. drop of 30 degrees may cause Icing
Hvy. Raind4+3d12 hoursF:x3/4, C:x3/42d12+10x3/4x3/4-10%/turn+10%Temp. drop of 30 degrees may cause Icing
Thunderstormd8d4 hoursAll/24d10x3/4x3/4-10%/turn+10% (+30% if horsed)Lightning 1/turn, 1% chance of being hit, 10% if under trees. 6d6 dmg.
Tropical Stormd6/dayd3 daysF:/4, H:/4, C:NA3d12+30x1/2x1/2NA+30%Every 3 turn, 10% of Gust damage if Wind Speed > 40 mph. d6 dmg/full 10 mph over 40
Monsoond8/dayd6+6 daysF:/4, H:/4, C:NA6d10x1/4x1/4NA+30%Every 3 turn, 10% of Gust damage if Wind Speed > 40 mph. d6 dmg/full 10 mph over 40
Galed8/dayd3 daysF:/4, H:/4, C:NA6d8+40x1/4x1/4NA+20%Every 3 turn, 10% of Gust damage if Wind Speed > 40 mph. d6 dmg/full 10 mph over 40
Hurricaned10/dayd4 daysF:/4, H:/4, C:NA7d10+70x1/4x1/4NA+30%
(F:= Foot Travel, H:= Mounted Travel, C:=Cart Travel, NA= Not Allowed)  

Special Weather Table

WeatherAmount (in.)Duration or AreaMovement RateWind SpeedVision Range NormalVision Range InfravisionTrackingChance of Getting LostSpecial Effect
Sand Storm-d8 hoursNA5d1000NA+80%50% chance of d4 dmg every 3 turns until shelter is found
Wind Storm-d10 hoursAll/28d10+20x1/2x3/4NA+30%50% chance of 2d6 rock damage every 3 turns, Save vs. Dex for 1/2 dmg.
Earthquake-d10 hoursF:/4, H:/4, C:NA----50%+10% (+30% if horsed)Epicenter is d100 miles away, w/ shock waves extending d100x10 miles. First shock wave preceded by d4 mild tremors. These tremors cause no damage, but will cause untrained animals to flee to open ground. After d6 rounds, first shock wave hits. There are d6 shock waves d20 rounds apart. Effects are same as Cleric Prayer Earthquake.
Avalanche5d10d10 minutesMay be blocked----60%+10% if trail coveredDmg 2d20, Save vs Dex for 1/2 dmg. Creatures taking more than 20 pts dmg are buried and will suffocate in 6 rounds.
TsunamiWave height 10d20’d2 hours-5d10+10--NA-Dmg 2d20, Save vs. Dex for 1/2 dmg.
Quicksand-d100x2’ radius----NA+20% if skirtedCreatures wearing Elven chain or lighter will sink only up to neck if all heavy items are discarded and arms kept above surface. Others dragged under at 1 foot per round if still, 2 ft/round if struggling. Drowning occurs 3 rounds after head is submerged. Rescued characters take d6 dmg per round that head is submerged.
Flash Floodsee belowd6+2 hoursAll x3/4----5%/turn+10%Begins as Heavy Rain (w/ appropriate effects) and drops 3” water per hour. Rain stops when duration is half over. All low areas covered to depth of triple rainfall. Water remains for d5+5 turns, then drops 3”/hour. Current is 5-50 mph depending on channel.
Rain Forest Downpour1/hour3d4 hoursF:/2, H:/2, C:NAd6-1x3/4x3/4-5%/turn+20%Ground absorbs 6” of rainfall, then turns to mud. Terrain is now Swamp for purposes of movement.
Sun Shower1/26d10 minutes------95% chance of Rainbow.
Tornado1/hour5d10 hoursNA300x3/4x3/4NA+40%10% chance party transported to Ethereal Plane. Otherwise treat as tripe strength hurricane for damage.
Oasis or Mirage-d3x10’ radius------If real roll d20. 1-2 indicates inhabitants. 20 indicates poisoned water. Anyone who “drinks” from a mirage takes d6 damage from swallowing hot sand (Save vs. Spell to avoid).
(F:= Foot Travel, H:= Mounted Travel, C:= Cart Travel, NA= Not Allowed)   4. Any time that the temperature falls below 35 degrees, consult the “Wind Chill Table”.   5. When precipitation ends, check for occurrence of a rainbow on the “Precipitation Occurrence Table”.   6. When the DM needs the position of a phenomena, roll d8:  

Random Direction

  7. If the Wind Speed is 30 mph or greater, consult the following table:    

High Wind Effects Table

Wind SpeedOn LandAt SeaIn AirIn Battle
30-44 mphTravel slowed by 1/4, Torches blown out.Sailing difficult, rowing impossible.Eagle-sized and smaller creatures grounded.Missiles at 1/2 range and -1 TH.
45-59 mphTravel slowed by 1/2, Small fires blown out.Minor ship damage may occur (d4 HP), waves 3d6 ft. high.Man-sized and smaller creatures grounded.Missiles at 1/4 range and -3 TH.
60-74 mphTravel Slowed by 3/4, small trees uprooted, roofs blown off.Ships endangered (d10 HP dmg) and blown off course, waves d10+20 ft. high.No creatures flying except those from Elemental Plane of Air.No missile fire, All non-magical weapons are -1 TH, Dex bonuses to AC cancelled.
75+ mphTravel impossible, only strong stone buildings undamaged.Ships capsized, waves d20+20 ft. high or more.No creatures flying except those from Elemental Plane of Air.No missile fire, All non-magical weapons are -3 TH, 20% chance / attack that weapon torn from hand by wind, Dex bonuses to AC cancelled.
Use of Magic Carpets or Brooms of Flying become very dangerous in winds over 35 mph. The percentage chance of a person or object being blown off is equal to the Wind Speed in mph minus the Carpet’s MV/10. This percentage is reduced by 5% for every 100 pounds of weight. It is increased 1% for every 5 lbs. below 100 pounds.
Use of a Potion of Gaseous Form in winds greater than 35 mph may cause dispersion of the gas so that the creature cannot reform.

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