Friday, September 25, 2015

Drought in 2016 for Washington State?

This morning the Washington State Dept of Ecology held a press conference and released a statement predicting continued drought in the our region.   They forecast a dry fall, lack of snowpack, and conditions as bad or worse than this year.  The media, of course, picked up the story and amplified it a bit.


And state officials were busy tweeting about the coming drought situation.


The media and public officials are talking about a strong El Nino, a continued blob, the effects of global warming.  Some things they are getting right, but there is a substantial amount of confusion and wrong information being given to the public.

Let's examine what we really know.   And as I will show, the odds are that next year will bring substantial IMPROVEMENT over this year regarding snowpack and drought.

The first thing to keep in mind is that the key weather feature that has kept us warm and dry, the large high pressure area over the West Coast and eastern Pacific, is no longer there.

I can prove it to you.  Here are the anomalies (difference from normal) of the heights of a mid-tropospheric level (500 hPa) first for last spring (left) and for the last three weeks (right).  Red indicates higher pressure than normal (ridging) and blue below normal (troughing)



Can you see the profound difference?  The ridge is gone and there is no hint it is coming back.  In fact, the current strong El Nino will make sure of that.

We made change to a more normal pattern during the latter part of August, resulting in the return of precipitation to our region.   In fact, here is a plot of the difference of precipitation from normal for the past month.  Precipitation has been ABOVE NORMAL over more than half of the State, with some portions (north Cascades and Olympics) being hugely above normal.  This is not a drought pattern.

The new flow pattern has also had a large impact on temperatures, greatly cooling off our state.  Here is the difference of surface air temperature from normal the last month (the anomaly).  COOLER than normal over most of the state, particularly over the wildfire areas of eastern WA.
With the lessening of the warmth and return of rain, wildland firefighters have put out or controlled most of the fires.  Fire season is essentially over now.

So the main reason that we were so dry and warm (the eastern Pacific High pressure) is now gone.  And furthermore, its direct offspring, the BLOB (the area of warm water off our coast), is rapidly weakening.  To demonstrate this, here is the change of sea surface temperatures over the past month.
Blue is cooling.   The BLOB is in its death throes.  Sad, but true.


All good news, right?  But then there is the scary El Nino threat.  A very strong El Nino (warm sea surface temperatures in the eastern tropical Pacific) is developing-- in fact, the strongest since the late 1990s.

Based on past experience, strong El Nino's have their main impact after the new year, mainly making it warmer than normal, resulting in less snow pack than normal (about a 20% reduction on average).  But this is HUGELY MORE than the snowpack we had last year (80% reduction).

NOAA and others run seasonal climate prediction models out to roughly 9 months.  What do they say?  The largest ensemble (average) of many models (IMME, International Multi Model Ensemble), shown below, prediction wetter than normal conditons on our NW coast and near normal for most of the rest of our area for October, November, and December.  In stark contrast, to the the drier than normal fall suggested in the Seattle Times headline story today.

For January, February, and March IMME is going for drier than normal over the NW and much wetter  across CA.  Classic strong El Nino pattern.  Big relief for California.

What about temperatures? Both fall and winter are predicted to be warmer than normal by 1-2C.  Substantially less warm than last winter over us. That  will reduce our snowpack.


So temperatures and precipitation are running near normal now and I expect the same will be true for precipitation overall until the first of the year.  There will be rain and storms and we will have an opportunity to fill our reservoirs.   After the new year it will be warmer and drier than normal, but not as warm as last year.  So there should be a far healthier snowpack on April 1, but less than normal.

Armed with this knowledge, the folks than manage our reservoirs should store as much water as possible as early as possible.  We tend not to have major floods in strong El Nino years, so they can fill the reservoirs higher than normal with less fear of dangerous overtopping.

The drought is not going to get worse and we should be in a much better place next spring than this year.  And California will get substantial relief.

I really worry that some of the media and in political circles are going too far in painting an end of the world picture for next year.   Crying wolf undercuts credibility.

20 comments:

sfsadff said...

Cliff, do you have any maps that compare the predicted temperature anomaly for Jan-Feb-Mar 2016 to the recorded anomaly for Jan-Feb-Mar 2015?

Alex Horner-Devine said...

How do these predictions for the fall/winter of 2015-16 compare with predictions for the same period last year (2014-15)?

Dave Steckler said...

When it starts raining for real, the media will switch over to "Flood 2016!"

The media exist not to communicate information, but to make money. Selling papers in the old days, generating click-through today. And scary, scary headlines do just that.

Same as it ever was.

Joseph Ratliff said...

As this article illustrates, the "panic state" (and data cherry picking) that the media portrays is not necessary ... and is probably worsening the situation. We need to react to what will actually be happening, not what makes a good apocalyptic media story.

AGW, the changing climate, etc... are all real problems (supported by science) that need addressing, for sure. But over-reaction to these problems can also be a worse problem in and of itself.

The media organizations that create these "stories of doom" are not doing so in the public good.

Beth Niquette said...

This was a GREAT post. Thank you! So what about snow??? Do you think we'll see snow this winter?

Andrew Smith said...

As we mourn (celebrate?) the death of our warm "Blob" in the Pacific, it appears its arch nemesis, a "cold blob" has appeared in the Atlantic. It's not right near the northwest, but I would be curious to hear if it will impact us, and how it will impact East Coast weather. Thanks!
http://www.washingtonpost.com/rweb/biz/some-scientists-are-worried-about-a-cold-blob-in-the-north-atlantic-ocean/2015/09/24/93990fb12089db51accf0630a45d51f7_story.html

Bob said...

re: your very last sentence -

How does one undercut what one does not have?

faronium said...

I understand frustration when the media reports are heavy handed on topics that have little evidence to justify the heavy handedness. But, your post seems to be crying "there is no wolf" and I wonder if that is any more appropriate than dooms-day predictions in the media given that seasonal predictions (which have very little skill although admittedly more skill during a strong ENSO phase such as the one we are under) are pointing to normal precip for the fall and drier conditions for late winter and early spring. The CPC projections throughout winter 2014/2015 were for a drier than normal winter in the Pac NW and, as you pointed out on numerous occasions, last winter wasn't a precipitation drought. It was quite normal. The central North American coast could as easily have an anomalously wet winter as break records for dry. From there, spring is a total crap-shoot and where much of the damage was done in 2015. Finally, the bulk of our snowpacks are formed in the months forecast to be the driest so the warm + dry first part of 2016 suggests that, if anything, snowpack will be quite low. So, I think the more honest article would state that all guidance suggests a drier than normal rainy season but this guidance is subject to considerable uncertainty.

I think another thing to consider is that, while overwrought stories in the media are frustrating to a scientist who knows better, they can help to move the needle of a public that can be highly inert as a whole. Blob-like if you will. I'm thinking of numerous issues both in climate science and social science where very long campaigns involving both careful analysis and relaying of that information and megaphoning media players have resulted in at least some social change. Granted, one wants the needle to move in the right direction and certain media outlets have a stake in moving the needle against better evidence, but I digress. My point is that a relatively subtle news release by the WSDoE was GREATLY amplified and the response from the public will probably be muted but maybe in the right direction. If a small percentage of people read the headlines and think "oh, perhaps we should continue to think about conserving water" then mission accomplished.

Gordon Fulks said...

Thanks Cliff. I appreciate the level-headed assessment from a very competent meteorologist, especially when the media goes crazy with its politically motivated predictions that have no professional competence behind them.

If you were to look ahead to the following winter of 2016-7 at the tail end of the present El Nino, would you expect massive mountain snow accumulations, as we experienced in the winter of 1998-9? I'm especially thinking of the 1,140 inch (95 foot) snow accumulation on Mt Baker that winter. It set a Washington State record, a US record, and a world record. Our El Nino this time will probably not be as strong, but should we expect similarly impressive (though perhaps not record) snow as it wanes?

Of course, Mother Nature will always have the final say. That is probably why I prefer being a physicist. We typically explain why something turned out the way that it did, not why it will turn out a particular way!

I think that meteorologist Joe Bastardi, who has been very good at predicting recent past winters more or less agrees with you at this point. That gives us a "consensus." :-)

Gordon J. Fulks, PhD (Physics)
Corbett, Oregon USA

ga said...

Cliff, what data did the Department of Ecology use to predict the continuation of the drought? The prediction must have had some basis, you can't just make it up.

John Marshall said...

The media's job is to sensationalize to get clicks and sell newspapers. They have taken on this mission with gusto.

Global warming activists have taken on the job of trying to scare us into action. Also with gusto.

On their own, neither one is unexpected or malicious. My fear is that their alliance will backfire and makes things difficult for those who are trying to follow the science. As we are seeing with the VW controversy, you can lose a sympathetic following pretty fast if you cross the line. (VW diesel advocates have been extremely vocal and motivated in extolling their virtues these past years. Those same people are equally scathing in their criticism and litigation.)

Of course, the media benefits whether right or wrong. They have already lost credibility, so they can't be hurt.

I don't want to see activists lose their credibility. But if so, it will be partially a self-inflicted wound.

I still hope that our interconnected world can handle truth without exaggeration, although lately I have been growing more pessimistic about that. Thankfully this blog keeps it real. Thanks, Cliff.

hidden wave said...

Cliff, great post! As a snowboard shop owner, the term El NiƱo is usually a big scare to the classic Mt Baker "snow snob" which I am guilty of myself!. However after last winter we should have reset the "worst case scenario" button and should be thankful for a winter with 80% of normal snow pack. death to the blob is a wonderful thing! Hoping for a below average, but way better winter then last year winter with "pent up buyers" ready to hit the slopes!

iamlucky13 said...

I don't know about every city on the west side, but I do know that most of them will have no trouble at all filling their reservoirs.

I've been paying some attention to the reservoir management for Everett since the newspaper up here keeps telling us "we're going to run out of water in 7-8 months" (paraphrasing, but close to their actual words, last stated early this month). It sounded like such a ridiculous statement given our rainy winters I had to try to find out why they would say such a thing, so I educated myself on our water system and the seasonal forecasts (which this blog was helpful for).

NOAA's long term forecasts seem to be indicating the next 6-9 months will see precipitation about 20% less than normal.

The Everett reservoir sees over 4 times as much water flow through it in the average year as it actually holds. That works out to something like 8 times as much water as everyone depending on that reservoir actually uses.

So far from running out of water in March, as they're inexplicable trying to convince us will happen, it looks like we'll instead have only 6 times as much water as we need instead of the usual 8 times as much.

The way Everett usually manages its reservoir, it stops dropping as the rains return in September, and they let it fill up to about 80%, which happens in November, and sometimes December. They then hold it at that level for months to provide extra capacity for flood control. It's not until May that they actually let it start slowly filling the rest of the way, and it doesn't peak until late June.

I had originally thought the normal December fill to 80% might take until January, but based on your post with the added detail for the next 3 months, it sounds like there's a good chance the fall fill to 80% will occur as normal. It sounds like the only change the water managers might want to make (just to be conservative...there's no apparent need to), is to be less aggressive about spilling excess water in April and May, to ensure they start the summer completely full. The risk there is the lack of unused storage could mean a big June rainstorm would force them to spill enough water to cause flooding on the Sultan River downstream.

Josh S. said...

It's just sickening when the media exaggerate stuff like this.

Mark said...

Drought? What drought? I recorded 40.3 inches of rain since Oct 1, 2014. About normal for west Vashon.

The excessive heat in the forest dried out the sword ferns, red elderberry, bracken fern and salmon berry. The moss on the trees is more brown than most summers. There are more dead fir saplings then usual. Some of the medium sized Firs lost up to a third of their needles but most appear okay. The evergreen huckleberry, big leaf maple and salal appear normal. The Alder and Indian Plum normally drop leaves in the late summer to conserve water.

There were far fewer mosquitoes than normal thanks to the dry May and June. Spiders seemed to be fewer than normal too. Hornets were typical, they tried to ground nest in our potted plants.

Not scientific, just my general observations from 25 years of tramping through our woods.

Abe Jacobson said...

Cliff,
Spot on!
But if I am not mistaken, I recall that the State Climatologist himself made a really dire prediction for continued drought- I heard him on KUOW. Is he not in close contact with you and your Department at UW?
Abe Jacobson

Shawn Brunel said...

1982/83 el nino was wet from Washington state all the way to San Diego California. I hope the warm pdo phase doesn't completely go away. Cold pdo means more La Ninas and droughts for california. If the warm blob turns into a horseshoe shape and not be at record levels i would think it would be better at keeping the evil ridge at bay.

Pete Spear said...

Thanks for the logic and reason here. All too forgotten in the media

Coug66 said...

Encouraging report. Thank you. As a side note, it was a great year for Western WA grape growers.

AnotherGuy said...

sfsadff, I agree with you. Cliff, you would be better off comparing the forecasts from last winter with the corresponding forecasts for this winter. Show the SSTs from this time last year, and compare with the SSTs right now. Don't compare the forecast for this winter with what verified last winter. The variability in forecasts frequently doesn't match reality.

Essentially, you're giving us a lot of apples and oranges. While I'm certainly not going to be making any predictions for this winter, I think you're doing all of us a disservice with these faulty comparisons...