In part 1 ( #208 ) I discussed my proposed overhaul for individual storm cells. However, in part 2 I will discuss more complex systems that are comprised of individual cells (or storm objects), so I propose the addition of clusters and mesoscale convective systems.

First lets talk clusters. In the real world thunderstorms most often form into clusters, so in the mod I propose that thunderstorms have a higher chance of forming in clusters than they do individually.

Here is a storm cluster vs. isolated storm.

Storm clusters behave like a cluster of isolated cells, however cells in clusters are much less likely to produce medium-large sized hail or severe winds than an isolated cell. A cell in a cluster has the potential to become a supercell, however these supercells will, for a grand majority of the time, only produce weak (F0-F1) tornadoes. Cells in a cluster also do not microburst.

Also, importantly, only isolated cells follow the aim at player rule if aim at player is enabled. Individual cells in clusters and mesoscale convective systems do not aim at the player.

Now onto the next part.

Mesoscale Convective Systems:
In real life Mesoscale Convective Systems are the common type of summer thunderstorm development where storm cells or clusters are organized into a more complex system. For the mod, I propose to add the following mesoscale convective systems:
• Mesoscale Convective Complex
• Squall Line
• Derecho

Let’s start with the Mesoscale Convective Complex (MCC)

In real life, an MCC is a type of MCS that mainly forms at night. An MCC forms from thunderstorm cells and clusters that spread out over a large region and take on circular shapes in nature.
Real life sat photo of an MCC

How I propose to have the MCC structured in the mod.

MCCs in the mod would form at nighttime and begin to slowly dissipate when the sun comes up. In general, most cells in an MCC will be non-severe and supercells almost never form in an MCC.

However, this doesn’t mean MCCs do not pose a threat. MCCs would pose a threat in the form of enabling mob spawning in daylight, similarly to vanilla thunderstorms. While an MCC is in progress mobs will not burn in the sunlight and mobs will continue to spawn into the day until the MCC dissipates enough.

MCCs can form over a large ocean biome at any time of day (this will become important later in part 3).
Next up is the Squall Line!

Squall lines are lines of thunderstorms that contain strong sharp winds. However, in the mod squall lines will progress in stages like other storms in the mod.

Stage 0: Line of Storms. A line of storms is the proto-squall line. A line of storms is a broken line of isolated storm cells. These cells behave exactly like isolated cells (except they do not aim at player if aim at player is true since they are part of an MCS) unless the squall line progresses, meaning any of them could become a dangerous supercell or have the chance to microburst.

A Line of Storms

Stage 1: Squall Line
A squall line will be a complete line of storms moving across the map. These squall lines will comprise mostly of “windy” cells (no damaging winds) and a couple isolated supercells may be present, but these will only produce weak tornadoes if they do occur. Cells in a squall line can also produce small-medium hail.

Next up is the severe squall line.

Stage 2: Severe Squall Line
Severe squall lines contain cells doing damaging winds. When a squall line becomes a severe squall line, the majority of it’s cells will become severe wind cells (as a reminder, severe wind cells cause F0 damage as described in a previous issue I opened) and a few may produce medium to large hail. Like the Stage 1 squall line, the severe squall line can contain a supercell or two that produces weak brief tornadoes.

A severe squall line will also produce a shelf cloud ahead of it so the player will see the ominous looking cloud feature as the severe squall line moves in.
In real life a shelf cloud looks like this

I think this effect can be replicated by having cloud particles at an angle ahead of the squall line.

Next up is a stage 3 squall line. The stage 3 squall line is the highest squall line and has a special name.

Stage 3: Derecho
The Derecho is the rarest and highest possible stage of a squall line and can inflict some real damage. A derecho acts similarly to a severe squall line as in it has a shelf cloud and damaging wind cells, however it will take on a different structural appearance and most of it’s cells will be extreme wind cells.

The derecho will take on a “bow” shape as derechos do in real life. The extreme wind cells will be in the center of the bow while “weaker cells” will be at the ends. As another refresher, the extreme wind cells can cause up to F1 equivalent damage according to the system I proposed in a previous issue.

Derechos in real life move fast. So when a severe squall line transitions into a derecho it will begin to take on a bow shape and begins moving quickly across the map, the cells near the center moving faster than the ones at the end.

Derechos can also produce large hail in some cells and a couple embedded supercells may be possible in the end areas (not toward the center).

So that is what I have for adding clusters and mesoscale convective systems.

Relevant proposed commands

Weather2 storm create MCC
Weather2 storm create cluster
Weather2 storm create squallLine <0, 1, 2, 3, Derecho>

GUI config options:
Squall Lines and Derechos On/Off

In part 3, which will be posted later this week, I will be talking about possibly improving hurricanes and tropical cyclones. 😊

Bro you need to make your own addon to weather2. You have such great ideas, and I can't wait for them to be added to the mod, if it will be.