Hex Crawl 23 #38: Summer Weather on the Dry Plain

 4 hexes north of Alakran.

 

Another dull empty stretch of west Dulsharna plain, another weather post.

The hot summer months call for special travel rules that play on the perils of day activity in the lands close to the desert. Referring back to the weather system that rolls 3d6:

• Treat all 6's (precipitation) rolled as 4's (cloud cover).
• Remove two of these 6/4's from each roll, and 1's and 2's cancel 6/4's. So cloud cover can only happen on, say, a 4/6/4.
• To see any clouds in the sky requires two 6/4's to be rolled (before removal or cancellation). But in practica terms there is little difference between some clouds and no clouds.
  
• Average high daytime temperature is 100 F / 35 C, nighttime is 80 F / 25 C. Each 1 not cancelled by a 5 raises this by 10F/5C, each 5 not cancelled by a 1 lowers it by the same amount.
• Winds (rolls of 3) are also cancelled by 1's. 3-3-3 is a sandstorm that reduces visibility to 10'

And the effects of hot weather, using 5th edition exhaustion rules (a very under-used resource to toughen up the game).

Add 1 sun for each 1 on the weather dice (3d6), plus each 2 on the weather dice in Dumuzu (III) through Tisheret (VII). Subtract 1 for each 5 on the dice.

90F: 4 hours of the travel day are hot, travel requires 1 CON save at DC 13 every 2 hours (based on collective roll to save time, disadvantage in medium/heavy armor) or take 1 level exhaustion. Resting unshaded in hot weather requires 1 CON save per 4 hours. Rest in shade (min. 1 hr) and 2x water ration will each restore 1 level.

Desert-native and fire-resistant species take the next lower effect from each heat exhaustion level, immunity to fire = immunity to heat exhaustion.

100F: 4 hours are hot, plus 2 at midday are blazing (1 save / half hour travel, 1 save/1 hour unshaded rest)

110F: 6 hours hot, plus 4 at midday are blazing.

120F+: 6 hours blazing, dusk is hot.

Exhaustion levels:

1 - Disadvantage on ability checks

2 - Speed halved

3 - Disadvantage on attack rolls and saving throws

4 - Hit point maximum halved

5 - Speed reduced to 0

6 - Death

A creature suffers the effect of its current level of exhaustion as well as all lower levels. For example, a creature suffering level 2 exhaustion has its speed halved and has disadvantage on ability checks.

For my old-school 52 pages rules, I would simply cause 1 hp/level of temporary damage per level of exhaustion, with collapse at 0 and injuries to head and torso caused by any exhaustion damage beyond that.