El nino effect on high Sierra summer

I have the opportunity to go on a climbing trip to either the cascades or the high Sierra around mid August.

In 2021 I had a great summer sierra alpine season because afternoon thunderstorms were pretty rare. 75% of the time you could climb all day. But that was La Nina. If you have to be descending by noon, the quantity and length of climbs you're able to do goes way down compared to if you have all day.

Are people thinking that the tstorms will be way more common and/or more severe in the high Sierra this summer?

The National Interagency Fire Center says, somewhat amiguously:

During the next 4 months, teleconnections including an ENSO neutral to El Nino transition (Fig 5), -PDO and some active MJO periods are likely to influence the Jet Stream behavior and how the subtropical Ridge sets up. They are both influential in how the SW Monsoon behaves . Cut off lows or weak low pressure systems will remain a dominant weather feature during June while the SW Monsoon is still expected to be less than robust, especially compared to the previous 2 years. Lightning activity is expected to come from different origins during the next 4 months including Cut Off Lows, Monsoon surges (weaker) and a few Tropical surges from the east Pacific. Lightning is expected to be more problematic during August versus July. The 4 month outlook (Fig 10) calls for mixed anomalies due to the convective nature to the expected activity but near average is probably the best forecast. Eastern areas are likely to be favored for the positive departures from normal. Temperature anomalies will also be mixed. The better chance for heat anomalies will be found across the north & east as the summer progresses.

https://gacc.nifc.gov/oncc/predictive/outlooks/Outlook_NOps.pdf

Last summer had a very powerful monsoon at times, but it was also La Nina year. The SW monsoon isn't easy to predict and teleconnections besides ENSO probably play a role. 

My (limited) understanding is that there is no precedent for the current situation.  An usually strong El Nino after a extremely rare triple La Nina. Additionally there are record breaking oceanic temperatures due to climate change. This combination of events has never been seen before, at least since modern records have been kept.

 Predictions of what that unique situation is going to do in the next months is very difficult.

Currently, it's unusually cool and unsettled with T-storms every day. I got hit by one this past weekend

It's an interesting topic, hopefully someone else who is better versed in meteorology can chime in!

One reason to consider the Sierra this summer is that there's a chance we could have a lighter fire season due to all the snow we got. Or, maybe all the rain will lead to heavy brush growth, which will then dry out and burn. Hard to say. But a smoke-free august sure would be nice.

But I think I can say with confidence that you'll be able to find good sources of water in August. 

Bb Cc wrote:

I vote for the Cascades if you haven’t been there before. Short days in a new place comes with better expectations of changes.

And the Cascades are generally not prone to thunderstorms. They can happen, but aren't that common. Most of the time in the summer if it clear when you wake up, it's clear all day. Good for long days out. And there's lots of great climbing.

That said, El Nino is a poor predictor of Sierra weather, winter or summer. You might have expected a dry winter this year, based on the La Nina stereotype. That clearly didn't happen. Whereas the previous two winters (also La Nina) were dry. ENSO gets talked about more that it deserves, and it's predictive skill is significantly overblown. It's not worth considering in making your summer climbing plans.

I'd say just make a plan to go wherever looks more appealing to climb, and have a Plan B to pivot to just prior to the trip if the 10-day forecast looks grim. That's really all you can do. If the Sierra is what you're psyched on, go there. The Cascades are great too and also worth checking out.

JCMwrote:

That said, El Nino is a poor predictor of Sierra weather, winter or summer. You might have expected a dry winter this year, based on the La Nina stereotype. That clearly didn't happen. Whereas the previous two winters (also La Nina) were dry. ENSO gets talked about more that it deserves, and it's predictive skill is significantly overblown. It's not worth considering in making your summer climbing plans.

66% would make it a strong predictor, albeit an obviously small sample. I'm being a little pedantic, but I think people hear "predictive" and think "deterministic". The 95% win probability for Clinton in 2016 wasn't necessarily wrong (nor was 538 with the lowest prediction of around 77% iirc) it's just that the other side still happens, around say 5-23% of the time.

Which is the real reason why trying to use complex predictive models to determine future actions is poor. It's not that the model is bad or uninformative, it just that you'll be disappointed a lot. Less often than you'll be delighted, but only if you take 1000 trips, ya dig?

The ENSO blog is fantastic. Everyone should read it.

Spopepro O.wrote:

66% would make it a strong predictor, albeit an obviously small sample. I'm being a little pedantic, but I think people hear "predictive" and think "deterministic". The 95% win probability for Clinton in 2016 wasn't necessarily wrong (nor was 538 with the lowest prediction of around 77% iirc) it's just that the other side still happens, around say 5-23% of the time.

Which is the real reason why trying to use complex predictive models to determine future actions is poor. It's not that the model is bad or uninformative, it just that you'll be disappointed a lot. Less often than you'll be delighted, but only if you take 1000 trips, ya dig?

The ENSO blog is fantastic. Everyone should read it.

"All models are wrong, but some are useful."

Do Cascades in August and high Sierra in late Sept.

Win/win

https://www.cpc.ncep.noaa.gov/products/predictions/long_range/

https://www.cpc.ncep.noaa.gov/products/predictions/long_range/seasonal.php?lead=2

Not a thunderstorm prediction per se, but if it's not going to be particularly wet, probably not particularly thunderstormy either. If you're driving, you can choose which direction to jump based on forecast or outlook.

Considering the current trend, I’d expect a cold, wet summer. That being said, cold and wet in California isn’t really saying much. Just go, watch the weather and pay attention to it while out. A day out exploring instead of climbing because of thunderstorms isn’t a lost day. It’s an opportunity. 

Howard does an amazing job with forecasting for the Sierra.  Follow his reports for information on long range and short range predictions.

https://mammothweather.com/