North America Monsoon 2023: The unknown, & Stranger Things... Pt #1

[Silas_Sancona]

It's that time of year again when the Southwestern U.S and N.W. Mexico enters the best season here..  The heat, towering walls of dust ..Lightning filled evenings, and humid, Hawaii-esque mornings..  That time of year when somewhat boring dry and thirsty landscapes are magically brought to life and can resemble places far wetter than one would assume.. 

Unlike prior years, i'm breaking this year's Monsoon thread into 2 parts:  ....The here and now,  and some personal thoughts on what may lie further out on the horizon..  Some interesting insight on what plants can tell us about weather patterns at certain times of the year as well..



Starting things off... Pretty quiet atm across the region.. We're actually a bit cooler than usual -for June-  right now..  A result of the weird spring pattern the western U.S  ..and entire northern hemisphere...  has been experiencing since ...last fall..  which has kept the summer subtropical high -that should be nudging it's way toward the 4 corners- suppressed into Mexico / east over southern TX, and a branch of the subtropical jet positioned in such a way to bring continual troughs and cut off Low pressure areas over California / Pac. N.W. ..which thus acts as a wall, keeping the subtropical high from moving north..

While we did experience a weird, un-May like surge of moisture many ( inc. myself ) nick named  the " May -Soon " it was not a sign of an early start of the " traditional " Monsoon set up..  In that case, one of the cutoff lows that have plagued CA through the spring got stuck under a large high pressure area ..positioned over western Canada, in what is called a " Rex Block " set up.. 

The cut off low was in such a position where it could pull up enough moisture ..both from Mexico, and from areas east of AZ, where it had been wetter at the same time,  and stuck around long enough to allow the right dynamics to occur over AZ and N.M. for some legitimate Monsoon-like Thrunderstorm activity.. 

What was unusual about the set up is that it lasted for nearly a week..  and included a brief ..closer to Monsoon-like set up as a piece of the subtropical High, building over Mexico, tried to set up near the 4 corners.. For a day or two,  before the entire pattern set up shifted....

While most areas saw barely anything, a few spots, inc. Tucson, and Safford ..small town N.E. east of Tucson, saw unusually heavy rainfall totals ( By May standards ). 



Needless to say, anything more than a few sprinkles is rare for the driest portion of the year in most of AZ..  A sign of things to come?   or,  just a fluke..  We'll see.. I will say that in the last few years, we have had some other Monsoon-like episodes that fly in the face of what is typical for late spring in the desert..

Looking at the season ahead,  .........This could be one of the more interesting years...  

While the majority of folks making forecasts are suggesting this year could end up drier than normal, and warm / hot,  a few other folks, who have had a somewhat better track record the last couple years, are suggesting more normal conditions.. One person is even pushing the envelope a bit again suggesting another wet summer.. Really skeptical of those thoughts, though that person's aim nailed the bulls eye the last 2 years..



While the Monsoon cycle over North America has always been tough to figure out each year, we're really in somewhat uncharted waters this year...  Coming off two, back to back wet summers, it is easy to think that there is no way we see another wet summer. 

While El Nino contiunes to develop, it may not end up being quite as strong as earlier forecasts had thought.. Add to this the exceptionally warm waters in the Atlantic, and  North Pacific  which, in the case of the N. Pacific, could dampen the effects of this years warm ENSO cycle ( Muted SST temp contrast(s) between the polar regions / tropics ) ..  Warmth in the Atlantic could prove a competing factor ( for tropical storm activity ) ..which is somewhat unusual -but not un-heard of-  during a developing El. Nino..

El. Nino itself has been associated with drier than normal Monsoon season activity as well., but this not set-in-stone ideology.   On the other hand, El Nino can also enhance Tropical Cyclone activity off Mexico, with remnants ..or borderline tropical systems themselves making it up into AZ, CA. or N.M.

As mentioned in the past, wet winters, esp. those where the west had an above normal Snow pack were assumed to be detrimental to the following summer's Monsoon ( Because all that extra moisture keeps the land cooler longer,  thus the 4 corners high takes longer to set up later ) .. This idea has it's flaws though, so it may not turn out to be as accurate as first assumed..

Add to that what could be a reasonably active Hurricane season in the Atlantic..  ..and the chances that some of that moisture treks west across the Gulf of Mexico, ending up either off the west coast of Mexico, or moving toward AZ/ S. Cal..

Adding in another potential factor, the large tongue of colder than normal water that has been anchored off California / N. Baja so far this year could influence both the eventual peak strength of El Nino, but also this summer's Monsoon cycle.. ( providing more temp gradient contrast between the Pacific and land areas.. Pulling in that cool / cool-ish, but moist  Pacific air is part of how the Monsoon circulation gets itself going )

I myself don't really know which "thoughts" will pan out ( ..too early to see a trend -either way- anyway ) but can see two distinct possibilities..

First is pretty easy.. majority of Forecasters' / longer range model " thoughts " prove correct and we end up w/ another thud dud " non soon " ( ...Remember 2019 or 2020? )  👎

On the other hand, perhaps the season -overall- leans slightly dry, ..but not horribly so.. and then gets a good boost from a surge in tropical storm activity later..

...As weird as this year ( ...and the last couple years ) has been, maybe we see a set up similar to 2021, where the subtropical high configuration set up in such a way that the Southwestern U.S., Mexico, and most / all of CA sit beneath the High Pressure area, allowing plenty of moisture to flow north and west from Mexico / Gulf of Mexico at times..  The set up in May was similar, but brief, and lacking a well entrenched 4 corners high..

last year ( 2022 ) was similar to '21, although places like Tucson and Phoenix proper weren't as wet as it could have been ( ...most areas of the state were quite wet though ) 

This year? .. we get, what we get.. That is my prediction..  We've had 2 wet summers, and a pretty wet winter ..so, if this summer is a total dud, things won't be quite as dire heading into next winter..

As everything looks right now, As nice as avoiding 110+ heat has been so far,  we need to see the weird pattern we've seen all spring end so the 4 Corners high can set up and get to work..  Some indications that may occur as we end June, but, i'm not all that sold on the idea yet.. ( keeps getting kicked down the road / troughiness near California / Pac. N.W.  trying to hang on, -like a bad relationship ) 

Pacific hasn't really started to get active either.. so..  Wait  n' see..   Not looking like we'll kick things off early this year, which isn't the best of signals for a good season ahead..  On the other hand, maybe there is a sudden " snap back ' in the pattern as we start July,  and things change quite quickly..

Regardless, should be an interesting year of stranger things across the country ..and in my own back yard..

Current SST's off CA. and in the Gulf ( of CA ) Remember, 28-30deg C is the magic number  range we want to see, esp. in the northern end of the Gulf ( ...of CA. ) to get the wet Gulf Surges cranking..






Current SST Anomalies off CA, and in the Gulf / Western Mexico.. SOTO ( State Of The Ocean Data, as of June 13th ) Starting to see some + SST Anomalies build off CA atm.. Gulf is a mixed bag.. how much longer will the Neg. Anomalies off Baja hang on??




More later... Hopefully,   haha..

Dear The Tucson Monsoon, ...May your wet  record breaking streak pan out -again-  ..Just don't forget about Phoenix, ..this section of the East valley esp this year, alright?  lol..