It's June 15th, start of the region's summer rainy season ...and it is .....Hot as < insert preferred make a purist / annoying religious person knocking on your door turn beet red word here > out there..  June Nuke Fest in full swing today kids..

" Where is this rain they say comes on June 15th?? "  someone inevitably asks out there on the net    ...Well, Darwin award winner,  ....that isn't how it works,  most years at least.. You might want to get out of the heat so your head can stop melting too..  June 15th represents a " heads up " kind of start to the season, rather than when we might start seeing actual rain..  Do you stare down a a Cat 5 Hurricane on the  first day of Hurricane season? ..

For the season to start " officially " ..Old standard of 3 days w/ a Dew Point reading reaching / exceeding 55 deg has to occur.. 

..So yeah,,   The un -official start of the best season in AZ ...and most of the Southwest ( ...and California ) has arrived.. and   what will this year bring..  🤔   ....3 peat o' doom,  ..soon ?    or,  that strange effect of actual rainfall in the deserts, in summer.  ...Ya know, ...another tantalizing round of that " Monsoon Magic " most of us here look forward to, ...and greatly enjoy??  Could it really happen??  ...No way to tell right now kid..  but...

This year, i'm keeping things a little more simple than in years past ..those prior Monsoon Season threads being where you can go if you need to brush up on the nuts n' bolts of what / why n' how the Monsoon season here and in Mexico works..

This year, the focus is on some oddly intriguing contrasts between the weather forecasts,  ..at least when it comes to what is anticipated rainfall wise.    Heat? ..It's summer, ..and that aspect of the season looks pretty well guaranteed to waffle back and forth across the west all summer..  How far west?  ..as in  ...will coastal CA experience a heatwave or 3 this year? ..We'll see but, the potential is looking better this year compared to the last couple..  Potential for some deg. of marine heat wave  developing along the California coast may factor into that too..   ..Could that factor influence a wet summer ahead?. 


The   for the currently suggested - by - most " wetter than average " outcome for this year's Monsoon Season forecasts:


** Current ENSO plume forecasts: ..Starting just below 0 = good as we reach July.. Can see where things were at in July of last year ..which ended up being " Doom Soon", part 2..  You can reference back to past years' threads on how where ENSO sits at this time of year can influence how the monsoon might ...( because nothing is ever 100% perfect )  end up... 




PDF corrected values:



In a nutshell:  more negative the value  = better odds toward a wetter outcome.. Higher " + " value # = drier is more likely..   Typically.   ** This is however not a perfect outcome indication  **


For later discussion ..if there is any hint in the currently suggested trend that is still present in September, could we be looking at La Nina winter,  #2??? ..and a legit La Nina winter at that??



** Current SST Anom. #'s as of yesterday, via SOTO ( State Of The Ocean ) data.. Note the warmer readings right along the CA margin..  Another " you'll have to go back and look "  point but, several studies have suggested that when the waters right off California and Baja trend warm / above normal,  that can help provide an additional moisture source for monsoon season driven storm activity, both here and across the region. ...Combined with where moisture for our rainfall typically comes from ( Gulf of CA, Mexico, Gulf of Mexico )

Temp set up in the Gulf ( of CA ) looks  too.  Remember, 29C + in the northern Gulf is the magic # for rainfall initiation across AZ







** Wet southern Plains ( Eastern New Mexico, Texas  ..even Oklahoma,  to some deg. )  = another positive potential moisture transport source, during wetter years...  Dry there thru the spring / early summer? = can signal a dry year here later. 


**  Mexico: ..From a distance, looking like a reasonable start to the rainy season across most of the country.. Obviously, that is where a lot of our moisture comes from  so,  ..dry there = likely dry here.


** Aside from the surprise rain event in March, winter here was quite dry and warm..  Link below outlines how various summers have gone following some of our driest winters ..Is also a big factor in this year's forecast..
https://globalfutures.asu.edu/azclimate/wp-content/uploads/sites/35/2025/05/AZ-Climate-Webinar-2025-Monsoon.pdf


** A recap of the 2021 monsoon..  Absolutely not a suggestion this year might end up like 21 ...or reach / greatly exceed it.. ( ...Though it would be really nice ) 
https://www.weather.gov/psr/2021MonsoonReview

Mentions in this recap talking about the AO ( Arctic Oscillation ) phase and 4 corners High position during wetter summers = interesting tidbits for this year's  monsoon forecast suggestions..

Where the AO sits atm / where it may go as we head into July..




** Been watching these closely since mid May and  both the daily GEFS 840 hour ..and daily ECMWF weekly forecasts continue looking reasonably decent as we head out of June / into July.. Mexico doesn't look too dry in the GEFS thoughts, and any " Dry / tan < Tan  = below normal > " shading in the recent ECMWF weeklys looks minimal over Mexico  ..and AZ.. 

Above / Below norm. Temp suggestions also trend normal ..or slightly below normal over parts of AZ by the 2nd week in July as well -for now at least..

** Subject to flipping back ..and forth again ofcourse,  but, current 14 day / 3 week forecasts suggesting some moisture / above norm. precip. lean creeping into AZ by months end. 


** E. Pac Hurricane Season is already off to a much better start than last year..  ..and may end up reasonably active..  More  for moving moisture north into AZ ..and / or CA and surrounding areas..





👎👎 outcome thoughts come down to:

** Mainly the current NMME  forecasts  ..I'm really skeptical of why data used by the NMME forecasts is seeing such a dry / really dry season..  Yea, it could happen but,  ..something doesn't seem right when a majority of  other forecast thoughts really seem to swing in a completely opposite direction..  Is often a reasonably reliable tool, though not lately..  Weird.. Or i'm missing something obvious..

** N. Plains have been a bit wetter than some had expected they might be by now..  It stays wet up there, that could throw some shade on a wetter outcome down here..  As mentioned in past years, some research has suggested a see saw -esque back and forth pattern between dry and wet summers in the U.S. Southwest and N. Plains / Upper Midwest..  ( IE: dry up there, better chance it is wet here.. etc ) 

** Longer range models used by Copernicus = mixed bag..  Some lean wet, some lean " equal chance " ..skeptical of data from them..

** CFS -anything- = pretty unreliable and all over the place.. trashing forecast thoughts from em'   

** Weird, sudden breakdown / Final Warming in the PV back in March... It was about then some of the wetter leaning model data started flipping dry / what was looking like a hot dry spring ahead turned ..sort of strange, ...sorta' muted 23 and last year..   Could that event have -any- lingering effect on things to come?  ..couldn't tell ya and highly doubt it, but, will be interesting to see if it does.. either way..

** May and June ( ..thus far ) portion of " Sunset Season 2025 " has been quite lacking..  Aside from the June Surprise,  some " eh " cloudscapes around at sunset, not much moisture drifting into our skies lately from the tropics..



Simply put:  While forecasting any and every monsoon season is quite a challenge, even in 2025,   this year seems to leave a few more doors slightly cracked open..  A lot of weird / strange / " that could be interesting " possibilities..  ..Hopefully in the right direction though rather than adding insult to the last two years. 


Me myself? ...while far S. AZ and Tucson and N.M.  did ok last year while we were left dusty,   thinking this year could see everyone get some good ..and much appreciated rainfall this year, state -wide.. 

CA, < Southern half esp. > could get in on some of it as well, esp. if Hurricane season stays active and we see lots of big easterly wave activity head west across Mexico from the Atlantic / Gulf of Mexico   ..but,  won't be shocked if not.   Don't expect Doom - Soon, Part 3  though.. ( I sure hope not.. ) 

New Mexico = may be a good year, esp. the western and southern half. 

Colorado, Nevada and Utah could also do ok.. Esp. if AZ and W. N.M. are wet.. 

NOAA's June forecast update gets issued on Thursday, so, we'll see what it looks like... Monthly update of the IRI ENSO forecast might be out at the same time too..

Regardless, another perfect song for the season..   Question is     ...how much will we " like it " when September 30th arrives..  🤔
 

Regardless, ready  for -anything-  Kind of have to be each summer here.  🤞..to the point of being slightly painful.. the next 3 - 4 months bring on lots ( ...and lots ) of bolts, not so hot / very humid days, ..and plenty of rain..  please...  



 

Im still irrigating as no rain yet and it's August.

22 hours ago, SueinAZ said:

Im still irrigating as no rain yet and it's August.

Yep... Water, ....then water again a day or two later, just to keep stuff alive =  That's the theme  -again-  this year.  

Looking at every short/ long- term WX model i can get my hands on?  ..Nothing looks good for the rest of the month / September. 

 

" Final stretch " Rainfall totals update:

With  20 - something days left in this year's monsoon season,  will we add any more to these ..essentially dismal.. totals?

..or has the final curtain fallen on Monsoon 2025? ...We'll see..


S.E. AZ



Tucson ( At the Airport ) : 1.99"




Central:



PHX ( at Sky Harbour ) .63"  ..If this goes nowhere for the rest of the season, this will be worse than last year ( 2024 = .74" ).




Northern / Northwestern AZ..



Flag.: 3.27"


Yuma:  2.09" and Tacna 3.08" ( Using official recording stations ) are the only two locations across the region that have seen above normal ( Yuma's Avrg. monsoon season total = 1.13" / Tacna = .96" ) 

Winslow and Prescott would be the only other two places that are also near or above their seasonal average atm. 



While both ABQ and El Paso are running below normal atm, N.M in general has had a better season than we have..

ABQ: 2.01"

El Paso: 2.84"



All that said, things could be worse..  Talk about loosing the house, lol..

Las Vegas: .02"



Lightning activity, which can often reflect how wet or dry a season has been has been pretty abysmal this year too ..even if there have been a couple decent light shows over the last week or so locally..

*** That said,  there have been years ( 2021 for example ) where lightning activity was lower than you'd expect during a very wet summer, or trended above normal during a few of the dry- ish years. 





A good, final quarter roundup on what the heck has hung this season out to dry from Zack ( Guido ) and Mike ( Crimmins ) via this months podcast over on CLIMAS. 

https://climas.arizona.edu/podcast/august-2025-sw-climate-podcast-wits-end

Had many of the same,  hint-y  thoughts mentioned during their discussion regarding  why this year could end up going the way we all hoped it wouldn't. 




We'll see what the final 20 - something days left bring...

 

On the final day of Monsoon Season 2025 ..Can someone say  Saved by the Bell..  For some at least?..

Compared to the start of the month, quite a turn around for a few areas on the final days of the season.


For many areas, September is not considered a " wet " month.  Sun angle is decreasing, which in turn means the " optimal " set up for the 4 corners high is slipping back into Mexico as the " winter season " westerlies start migrating south from Canada. 

That said,  there can be exceptions to that " general " rule..  WX pattern at this time allows for more transitional season / Tropically influenced rainfall events across the Southwest? = September can over achieve.. 


** Preliminary season totals..  Aside from the areas of the state which were already at / above normal beforehand,  Transition season event over the weekend is what pushed other areas much closer to ...or just over their seasonal average.  Phoenix, Globe, and El Paso seeing quite a bump, at the very last minute.. 



 Monsoon Tracker Data:


S. AZ.:



Cen. AZ.:




N. AZ:





El Paso:





Las Vegas:





ABQ:







Lightning Data:







06- 15 - 2025 thru 09 -29-2025  Rainlog.org data from across the state: 

Phoenix / Casa Grande area...







East valley close up..






Tucson area...











S. and S.E. AZ: 
















Rim Country / White Mountains...






*** For now, Maricopa Co FCD' s numbers aren't exactly correct when pulling up the seasonal data... so i'm not posting it. 



More data once the official analysis is completed..



Quick, final thoughts ..For now..


* While the overall season will lean dry,  The Strange Effect?  ..Absolutely in effect  this year..

* One or two bigger events spread across a mainly dry  ~roughly 3 and 1/2 month period? = will definitely temper some short term drought issues, but,  it won't offer much relief  longer term..

* With that said, at least we broke the dismal streak of the past two years and signals better times ahead..