Wanna come in to my heat dome?

Welcome back to The Strawman, the daily climate newsletter that’s like a warm tray of baked cookies from grandma - we fill you up with a deep seated happiness you probs haven’t felt since you were a child - yikes.

Today we’re diving into the world of jet streams and heat domes - people in the US are starting to get a little warmer and it’s worth looking at what’s going on.

Let’s dive in.

Heatwaves and heat domes

Some of us might have experienced what it feels like to accidentally step into a sauna with all our clothes on - for nearly 110 million Americans and countless Mexicans, that's the reality right now. 

A gargantuan "heat dome" - think of it as Mother Nature's convection oven - is parked over vast swathes of the US and Mexico.

With temperatures soaring up to a blistering 50C, it’s not just a hot day at the beach, with over 100 people dead in Mexico alone.

What’s going on?

So, what's cooking in this pressure cooker?

The secret sauce to a heat dome is trapped heat.

We all trapped butterflies under glasses as kids right? No? Just me then I guess…

Childhood to one side, this is what’s happening in the US right now - but replace the butterfly with warm air. Changes in ocean temperatures in the Pacific Ocean are partly to blame for setting the stage.

What’s going on is pretty simple, but dangerous:

1. Warm Pacific air gets stuck in the US Jet Stream (a band of strong wind)

2. Warm air expands upwards

3. High pressure creates a dome that prevents this air from escaping

4. High pressure also forces this warm air back down to the ground

5. As it sinks the air compresses releasing heat

6. This heat makes the ground lose moisture - making it even warmer

The result? Insanely high temperatures, with the dome blocking clouds from getting in that would bring them somewhat down.

Yikes - that’s not easy reading.

It’s a scorcher out there folks - a bit of sun is good, but this is too much for The Strawman.

In any case, we’ll see ya tomorrow.