Monsoon 2024, Part #3: Some Final numbers, what happened this year, ..and some final thoughts...

[Silas_Sancona]

After lots of delay,  time to play catch up and round out this year's Monsoon Season thread here in the Southwest..


As mentioned, while not quite as awful as last year,  2024 was still pretty bad in many areas, esp. locally.  That said, Tucson ..and a few spots down south ..and north of PHX managed to pull of a ..decent.. season.

 While such variability is a fairly typical mood of the Monsoon here, it was quite pronounced this year.


At the other end of the spectrum, while the northern / northwestern states generally fared poorly, it appears central and Southern Mexico erased some of their drought this summer.. At least according to the Sept. 15th update to their drought monitor.




Before i move on to some final thoughts ..inc. some musings regarding the future of the summer wet season here, some final numbers..


From the NWS Monsoon Tracker:

Tucson..   For a bad  year,  Not bad..


PHX.. .......



Valley - Wide Avrg. = just as awful..





ABQ:  Not great, but could've been worse..


Flagstaff:  ..Same thing..



El Paso:



..Rest of em, (  Yuma, Kingman, Las Vegas.. )  = In the toilet, not worth including..

Some other areas across the state:










From Rainlog.Org.  

Starting w/ PHX and surrounding areas: Tucson / surrounding areas below..

























Cen and S.E'rn. Borderlands











Far S.E'rn / Eastern AZ











Rim and surrounding areas N. and E. of PHX.













** What happened this year??     ..A quick summery:


While each year is different, what happened this year mirrors what we saw in '19, 2020, and last year..  Simply put, the 4 Corners ridge had a tough time anchoring itself over the " favored " area for long before getting knocked out of place.

In many cases, it would meander a bit too far south, which would limit the effects of whatever moisture was around, at least across central AZ, which is what occurred last year, and in '19 / '20.



While the finite details will vary,  this crude chicken scratch of a drawing represents a suppressed or " blocking " Monsoon Season Set up and represents part of what occurred this year ..and during 19, 20, and last year.  Under this set up, moisture can still reach AZ, but it's influence can be greatly reduced, esp. over a regional - scale area.

Wet winters / Above avrg. and lingering snow pack in the spring can result in this kind of summer outcome.





That said, the high did not sit right over AZ for quite as long ..when it would..  as it did last year so, while this summer was brutal, heat -wise, it wasn't quite  as bad as last year.   ....Not that that really matters, still insanely hot, even for this part of the world.

Far southern / Southeastern portion of the state seemed to stay in a better position when moisture surges from Mexico could work with the terrain down there and squeeze out decent rainfall. - in some spots at least. 

New Mexico started off solidly, but landed just below average, though a lot of the moisture surges experienced this year seemed focused on the eastern part of AZ and N.M.

Southwestern areas of AZ / far western and northwestern areas of the state generally suffered the same hot and dry fate as central AZ this year. 

California only experienced a couple good surges this year,  particularly last month when a good push of moisture brought ..pretty decent storms.. to parts of the Inland Empire, a few spots near Temecula seeing more rain -in a few hours-  than we did in many parts of the valley all summer, which is pretty unusual.


While the season did kick off early, -and with a little gusto,  which is sometimes associated with wetter years,  bottom fell out and better conditions / pattern set up for widespread rainfall had all but shut down early, by about mid August, which is a bit unusual, even if September rainfall itself isn't always as significant as what falls during the heart of the season ( = ~ roughly Late July thru late August.  )

Pattern-wise? not out of the question this years' hot n' dry, part #2 / repeat of last year  has the finger prints of a lingering El Nino / transition to La Nina that did not evolve as quickly as had been anticipated earlier on written on it.



Overall, this year lands within the ballpark of what i'd expected, ..with the exception of locally,  which fared much worse than i'd thought it might.    Regardless, majority of the important  areas, esp. down south, did good enough to keep everything going for another year.

Even up here,  bad as it was,  ..at least things weren't quite as dismal as last year..   Glass half full, right?



With La Nina looking ..rather weak.. atm at least,  as we head into winter 24 - 25, it will be interesting to see what things look like come spring, as the start of next years Monsoon season dawns on the horizon.



As mentioned at the end of the " CA / Southwestern U.S. winter " thread,  some faint glimmers of hope next year could be decent,  but,  those early thoughts are just something entertaining to watch -for the time being-  Gotta get through to the other side of the winter ahead  before  any faith can be placed into any " optimistic " looking WX model thoughts   first.

Fingers crossed though..


Parting thoughts  -and something else-  on the way.....

[Silas_Sancona]

And alas, some final musings on the future of the North American Monsoon and the latest video instalment of monsoon greatness from  world renowned, local Photographer ...and fellow storm junkie,  Mike Olbinski..


After year #2 -in a row- of a brutally hot and dismally dry summer rainy season, ..locally at least, some may start to wonder ..Could what has been seen be a sign of what lies ahead?? or just another cycle of typical variability.   ... questions that aren't as easy to answer as some might assume,  and questions that can lead someone down various rabbit holes that at times can contradict one other  ..leading the curious to more questions ..let alone more head scratching confusion..

..So, if there are so many variables to consider, how do we try to piece together the complex puzzle that is the NAM? ( North American Monsoon ) ..and how reliable are the various pieces found within all the various studies that have been done /  ..are still being done??

Again, not simple or easy to answer questions, though there are clues, ..a couple recent ( and on going ) studies in particular which might just help fill in some crucial empty space on that puzzle board..

When looking at all the factors involved,   ..Everything from upper air and Ocean temp patterns, short and longer term ENSO cycles, how topography -locally and in Mexico- influences things, Vegetation patterns -Currently,  and in the past / locally and further south..  there's a lot of information someone can spend hours digging through to form some sort of answer. 

That said, if there is one solid truth regarding our summer rainy season,  it is that it is fickle ..and rarely plays by suggested rules.  ..Is what makes each year interesting and looked forward to, even the bad years.  ..Much like the next instalment of X Y or Z major movie saga..  Will the next chapter in the story be good? a waste of time and money going to see it? ..or just ....eh? ..good enough, ..but still lacking   ...something


When trying to tease out the future of the NAM, various studies over the years have looked at everything from Tree ring data to various debris retrieved from Pack Rat Middens ( long-term Pack Rat nests ) ..to musing summertime past Jet stream patterns, as well as potential positive or negative impact / influence from more recent factors like modern land development for cities and Agriculture...

While there may be some truth within studies that have suggested that the NAM circulation may change in a manner that results in less rainfall / hotter extremes due to shifting oceanic and atmospheric circulations,  some recent studies, -that employ some very advanced examination techniques-, may hold the most valuable clues of all.. ..clues that are hard to refute and follow some of my own thinking on this subject..

I'm sure i've posted -at least- one of these studies in past discussions on this subject, but will post them again.. There are a couple other studies i'd read through w/ some interesting insights i'll have to find again / post some other time..  

Regardless, very hard to casually disregard data collected via ocean and lake bed sediment cores, various Isotope signatures noted from leaf wax, shells of Plankton ..or other ancient marine dwelling creatures ..and or stalagmite / - tite deposits hidden deep within caves..

...difficult ( at best ) to fuddle with stuff buried hundreds / thousands of feet below hundreds / thousands of feet of soil / water to influence the outcome of such a study / research  -in one direction or another.. 

That said, like anyone with a healthy dose of skepticism, i too want to see more data / continued studies revealing data that lands in the same ballpark -so to say- ..

Regardless, even if my thoughts may be more bull-ish / wishfull thinking than correct, some of the data observed aligns with  my casual non- professional climatologist musings on how summers here - and across the broader west / southwest -  could look in the future ..if things are changing as is currently suggested..

The studies:  Two can directly tied to the NAM, the 3rd, = more indirectly..  Again, there are some others i'll have to find again that i'll add later.

> https://par.nsf.gov/servlets/purl/10382896

>https://www.nature.com/articles/s41561-023-01282-4

>https://scitechdaily.com/isotopes-from-cave-stalactites-show-more-intense-and-frequent-thunderstorms-linked-to-global-climate-variability/


Thinking on all that, a quick look at the nearer past reveals more insight of where we've been,  ...and might be headed..

** Lower elevation areas of AZ during the Ice Age would have resembled the cooler ( though still warm -in summer - ) inter-mountain West w/ a landscape dominated by trees like Oaks, Pinyon, Juniper ..and other plants like Sagebrush.  " Desert " stuff ..Mesquite, Saguaro, Palo Verde and Ironwood,  would have been chased well south into Mexico by our cooler / colder winters. Precip regime would have been winter dominant ..Much like CA is currently..

** During this time, under such conditions, summer storm activity likely would have been far less common simply due to more upper Atmo. influence from the poles ( stronger westerly flow / a summer Jet Stream pattern that hangs lower in latitude ..which would be bringing in lots of dry / stable air off a cooler Pacific ) cutting off any surges of tropical air that might wander north out of Mexico during that time.  Redwoods may have grown much further south along the CA coast during this time as well.. ( Some Paleo -climate era studies i've read over which have suggested such )

** As AZ climbed out from under the last Ice Age, climate dried out = dominant veg. regime started to shift = " subtropicals " locked up in Mexico started moving north, while Oaks, Pinyon, and Juniper started retreating up hill to areas where it stays cooler during the summer..

Summer rainfall would start to increase due to less polar  influence on upper Atmo. patterns..  Simply put, while other factors are important too, the one major thing convective storms need to get going? ..Heat..  No heat = stratiform rain ..more often than not.  Differences between rain that falls from stratiform - type setups vs. convectively leaves a different isotopic  signature on sediment and/or plant wax.


** As it stands currently, AZ has a bi -polar precip. regime..  Further south one heads toward Mexico = rainfall is more summer dominant, Further north = winter dominated.. Major keystone species within the current vegetation patterns across the state follow this set up as well.

In CA, only far S. Cal receives enough summer rainfall to be considered somewhat significant. Currently at least.  Was not the case during the wetter part of the Pliocene when the NAM reached much further west. 


** If, under a shifting climate, that is supposedly only getting warmer, everything from various large scale ULL WX patterns, ocean sst's, plant zones,  critters, etc  are all shifting warmer, " toward the poles "  it only makes sense that the " basic " climate you see to your south, may become the climate you will experience ..at some point.. in the future..  Even if it isn't exact or uniform across the board.

We've seen this before as the the climate in the mid latitudes has oscillated between " more tropical " and " more polar " in the past.. Ancestral Palm, Ficus sps, ..and an Avocado relative growing along the shores of a warm / shallow Central Valley sea.. Crocodile, Iguana, and Boa Constrictors roaming -at least- southern AZ and far southeastern CA. Skeletal remains of an Ant Eater relative discovered  not too far south of AZ ..All point to a time when the southwest was wetter and warmer.. Likely summer rainfall dominant across the state ..and /or region..

" Tropical " trees like Bursera and Erythrina growing in AZ ..even today.. arriving during warmer times, but finding a way to survive the cooler times.  Now that it seems we may be shifting warmer, ..will they -and other tropical tree sps that grow close to the AZ / Mexico border- become the keystone sp. trees that dominate the landscape of the future here?? 



** While imperfect, the current understanding involving what gets the NAM circulation going is ..less winter snowpack / melts earlier = allows the land to warm faster / earlier in the spring which can allow the subtropical high to migrate north out of Mexico faster to a position that allows moisture to reach AZ ..and the overall southwest..

The opposite ( more snow / sticking around longer ) can often result in delayed and drier monsoons.

If this is the suggested future here under a warmer-leaning climate ( warmer winters / less overall snowfall / rainfall, early melt ..when snow does fall.. ) it only makes sense ..if the suggested understanding is correct,  that there would be more opportunities for wetter summers here..

While they may be sprinkled within other summers that are dry / hot, ( suggested by some studies involving an expanded subtropical High that blocks moisture intrusions ) i can't see how they'd disappear as some seem to imagine they might.  Quite possible those wetter summers end up wetter ..than some of our wettest summers thus far too.

..Such an idea might resemble the kind of set up like what we experienced in 2021 ( a hint at the future, perhaps )  where the Subtrop / 4 Corners high was displaced far enough north / northwest that ample moisture was able to reach AZ ..and other areas of the Southwest..

Imagine the current / optimal position of the 4 corners high shifting more towards say northwestern Utah / N. Eastern Nevada in the future ...or centered up over N. Colorado / southern Wyoming, rather than the 4 corners and that occurring every 4 -7 out of 10 years in a world where warmer sst's off CA and in the Gulf of CA can import more moisture into AZ and -at least- Southern CA...

To me, it seems like the rockies would be a great spot for the center of the subtrop high to sift to..

..Sorta like this.. Could this be the " 4 corners " of the future ?



Compared to this ( the current " idealized " set up )




All things being equal ..and aligning with the overall idea of Wx patterns " shifting polward in a warming world "  thoughts  ..could the " core " region of the NAM ( Blue and Purple lines on the maps ) shift north out of Mexico,  into the southwest, in the future??

May not make sense to some, perhaps a highly bullish take in the opinions of those who have their PHD's / Graduates in the subject  but i don't see why this could not be an outcome in the future, even one that is drier ..mainly because there is less winter Precip. 

** Influence of ENSO cycles..  A highly variable factor that could effect the NAM in one way or another.  Some studies suggest a constant El Nino type state in the future could negatively effect the monsoon, while other studies say the opposite.. Same with a future where La Nina rules.   A tougher piece of the puzzle to figure out.

Even looking at data since 1988 ( yes, i know i could have gone further back in time ) there is quite a lot of variability between above / below normal Monsoon seasons here and in Tucson, compared with the ENSO state during each year's Monsoon season..

Green = Above
Blue = Normal / Near normal
Yellow = Below normal

Tucson on the left / Phoenix on the right

Red = El Nino / Blue = La Nina / Black = Neutral ..Positive and Negative..





The future??

Tis all   ..up in the air..



....And after all that long winded rambling,  a few -of the many- reasons our Monsoon Season is the crown jewel of the Southwestern U.S.    ...and why we put up w/ the heat.

Even during two of the most annoyingly sub-par monsoon seasons, after one that was epic,  if you put your feet to the ground and stay optimistic, you can find some highlights to enjoy during the bad years.

Hopefully in the future,  the good years will be better than the worst..  Let us not go for a 3 -peat next year please..


A compilation of the '23 and 2024 Monsoons  from one of the best Photo / Videographers in the business, Mike Olbinski..  Not included here but Mike also hosted a monsoon season chase tour with the BBC a couple years ago.  His images / film clips have been seen in everything from commercials to big name movies.


**** All rights, credits, and content are the sole property of Mike Olbinski *****
 

Lastly,  As if Thunderstorms weren't interesting enough, how about being radioactive too... Pretty Sweet..   See ya when the 2025 season dawns

https://pratt.duke.edu/news/radioactive-lightning/