⛈️ It's Time to Look at Monsoon Season

El Niño will bring about a very different season this year than last.

If you are a longtime reader/watcher/follower of us, you know we chase the Plains storm season, particularly the Southern and Central Plains. You also know that we indulge in the beautiful Southwestern Monsoon most every year as well. This year should be no different, as I plan to do a few new things this season.

But, will it be a good season? Let’s take a look at what the data says.

Keep in mind that seasonal forecasts are always of pretty low confidence. A few small changes in the large-scale pattern can be huge difference-makers. I love writing these using an objective lens, but I also try to not take these or myself too seriously when doing so. 

The Experts

Overall the next three months (July – September) the Climate Prediction Center is predicting a lean towards below normal precip for portions of the Southwest, consistent with a quieter than normal monsoon. Most NWS offices in the SW Region largely agree with this overall outlook.

The confidence in this projection is highest across Eastern Arizona and Western New Mexico in particular, this sadly includes the promised land of SE Arizona where we typically see the best monsoon storms form most years (including up to severe cells).

Because of this (and what I think looks like a pretty massive ridge parked over the Southwest at least in July — the CPC is projecting a hot summer.

This all somewhat closely tracks what you would expect with an emerging moderate to strong El Niño episode in the Pacific, so this is not that surprising.

Model Data

Taking a look at the models reveals some of the reasons the CPC outlook says what it says.

The CFS (and most climate models) show a pretty tepid start to the monsoon season in July. This is heavily supported by shorter-term solutions like the CFS and Euro weeklies, which park a powerful ridge over the SW for the first couple/few weeks of the month.

Signals amongst models become much more mixed into August, so I’ll be optimistic and share the CFS again which shows a tilt towards normal/wetter conditions across portions of the Southwest. Notably, there are pretty consistent signals for wetter than average over the Central and Northern Plains. I suspect I’ll be chasing supercell and tornado risks in July/August, especially off of the Colorado front range and Raton mesa.

A consistent signal also emerges somewhat for September of the pattern turning wetter for much of the country, including the Southwest. September is still monsoon season and I suspect we might have a pretty solid transition event or two in September or October, which can produce beautiful supercells over the desert landscapes of the Southwest. We also might see a return of supercells in September on the Southern Plains this year (kind of like we saw a return of June).

The Bottom Line

I do think a few things are probably true here:

1. A pretty solid monsoon-like season on the Plains at the edge of the dominant SW Ridge (even some supercell chases as brushes of N/NW flow work around the ridge). I think this is particularly apparent on the High Plains.

2. Pretty intense bursts of monsoon activity when they do happen, however infrequently. These will likely be concentrated more in August/September.

3. A likely pretty active Northern Plains/Canada summer supercell season.

I have joked with people on private chats that my Summer 2023 season will likely surpass my Spring 2020 season in terms of chase quality. It won’t take much and I am expecting for that to be the case. I might find it in my heart to forgive the atmosphere for that dreadful year of drought and fire if so.