Friday, April 21, 2017

THE Surf Report

All signs point to 'YES'.

SURF:

We've been on a roll lately. Fun NW along with fun SW along with somewhat favorable weather has resulted in rideable waves all week.


Looks like things actually get better this weekend as we have a NW windswell/groundswell mix filling in today along with new SW. Look for head high sets and great weather. Saturday will be more of the same as the NW backs off slightly and the SW picks up slightly. Best spots will have head high+ sets.


Sunday morning drops slightly to the shoulder high set range then new W shows up late Sunday for head high sets again. All in all a fun weekend. And water temps are starting to rebound to 63.


Tides the next few days are 4' at sunrise, down to 0' after lunch, and back up to 4' at sunset.

FORECAST:
On Monday the new W peaks for head high sets and we'll still have background SW that lasts through Tuesday to help prop up the surf in the chest high range.


By Wednesday we get a shot of W windswell/groundswell and another NW on Thursday. Along with background SW, we'll have head high waves again.


After that, models show another SW arriving next Saturday for head high sets and yet another smaller SW around the 2nd of May for chest high waves. Lots of good surf on tap and nice weather to boot the next 7+ days. Make sure to keep up to date on the new swells at Twitter/North County Surf. 

WEATHER:


Northern California got the last of the showers/snow this past week and down in So-Cal just some night/morning low clouds/fog. As you noticed yesterday, high pressure started to fill in and we had sunny skies and warm weather. That builds through Saturday and we'll have great weather and temps in the mid to high 70's at the beaches. Low clouds start to return Sunday into Monday for slightly cooler temps, then normal conditions the rest of the week (night/morning low clouds/fog and sunny afternoons with temps around 70). Why would you live anywhere else?! Besides Tavarua of course.

BEST BET:
Saturday with great weather and good NW/SW. Today and Sunday don't look to shabby either though. And while we're at it- next weekend should be good. Again.

NEWS OF THE WEEK:


El Nino, is that you? If you’ll remember, earlier this year I mentioned that forecast models were already giving up on La Nina and, gasp, prophesizing the return of El Nino: So what’s been happening since then? Is our water going to be 70 degrees in May like it was in 2014? Are we going to get tropical rain all summer like 2015? Are we going to get a bazillion hurricanes like 2016?! Calm down, calm down, let’s have the people at the National Oceanic and Atmospheric Administration give us the latest:


The tropical Pacific Ocean has been giving mixed signals recently, making a forecaster’s job even more difficult! In short, many of the computer models we use are predicting the development of El Niño over the next several months, but current conditions in the tropical Pacific aren’t showing many of the elements we’d expect ahead of a developing El Niño.

We’ve had neutral conditions since January, and forecasters predict that continued neutral is the most likely scenario through at least June. By September, chances of El Niño rise to about 50%, a slight edge over neutral (~40% chance) or La Niña (~10% chance).

What are forecasters seeing now?
We rely on prediction models because they provide the most likely evolution of the ENSO system better than we can compute on our own by eyeballing maps and charts and analyzing what has happened in the past under similar conditions.

Right now, many climate forecast models do predict the development of a full-fledged El Niño during this summer or fall. It’s likely that these models are acting on the much warmer-than-average waters near the coast of South America—the “Coastal El Niño” that I’ll get to a little bit later in this post. Predictions for the Niño3.4 region in the east-central Pacific show chances for El Niño ramping up over the next year.

While nearly all of the available dynamical models are predicting an El Niño, only about half of the statistical models are, and those that do are predicting a weaker event than the average of the dynamical models. Statistical models are based on previous events, and right now the tropical Pacific does not look much like it has before past El Niños.

El Niño sets in when the ocean and the atmosphere show coupled behavior—that is, when a stronger link develops between the warming waters in the central and eastern tropical Pacific, and the slowing down of the Walker circulation, in which the westward-blowing trade winds near the surface weaken and the eastward-blowing upper level winds also weaken.


Right now, the tropical Pacific Ocean is split. There is warmth in the eastern Pacific Ocean (the Coastal El Niño—I’ll get to that, I promise). But the western and central Pacific Ocean actually look more reflective of cool, La Niña-like conditions! This is indicated by drier conditions near the Date Line and wetter conditions over Indonesia.

Surface winds over the west-central Pacific have been blowing stronger than average (a stronger Walker circulation, more like La Niña). Meanwhile, the surface temperatures in the central Pacific are cooler than average, also more like La Niña than El Niño. Even the sub-surface ocean temperatures are below average in the central Pacific over the past month. In advance of an El Niño, we would want to see heat content that is above average.

Finally! The coastal El Niño!
During the last two months, strong warming developed in the eastern tropical Pacific Ocean, hugging the western coast of South America.  Back in early February, Peruvians designated this abnormal warmth as a “coastal El Niño” and it has resulted in unusually heavy rainfall along the coast of Ecuador and northern Peru, rivaling the major El Niño events in 1997-98 and 1982-83.

This local event is different from the El Niño-Southern Oscillation (ENSO) we’ve come to know and love, which spans the width of the Pacific Ocean basin. Coastal events tend to arise during the February-April period because sea surface temperatures are typically near the warmest of the year. Heavy rainfall starts when surface temperatures exceed roughly 28˚C (82°F).  between the left and middle panels, showing the SST anomaly, or departure from average, during March 2017 (right panel). Climate.gov map from IGP using UKMet OSTIA data.


Does a coastal El Niño often turn into ENSO events?
Interestingly, it was Peruvian fishermen who first gave “El Niño” its name in the late 1800s, when they noted unusual oceanic warmth near their coast.  Later researchers, most notably Jacob Bjerknes in 1969, realized that the El Niño—the cycle in ocean temperatures—was often connected to the atmosphere above it, the “Southern Oscillation.”  The latter is more far-flung, and reflects the change in the tropical Pacific circulation (winds, convection) that overlies changes in the ocean.  The basin-wide El Niño-Southern Oscillation (ENSO) phenomenon was corroborated in the early 1980s, when detailed information became available with the advent of satellites and advanced monitoring systems like the Tropical Atmosphere Ocean (TAO) buoy array.

Although basin-wide El Niño events were once thought to originate as coastal El Niño events, we’ve since learned that this is not always the case. Coastal warming sometimes precedes strong coupling between the ocean and atmosphere (ENSO events) that span the entire tropical Pacific Ocean, but not always.

In this war of East versus West, which will eventually win out?
Most of the dynamical models favor the eastern pattern “winning” with an expansion of the coastal El Niño into a full-blown El Niño event. Mind you, only once since 1950 have we seen a sequence of El Niño, La Niña, El Niño during three consecutive years—in 1963-66.

While many models have been quite persistent over the last few months in their predictions for El Niño, they carry fairly wide uncertainty envelopes that translate into tempered probabilities for El Niño.  Plus, we are still in a period of less skillful forecasts associated with the spring ENSO predictability barrier.  Given this low model skill in the past at this time of year, and the conflict between the warm eastern Pacific and the relatively cool western Pacific, forecasters find that the odds of development of El Niño in the next six months, while elevated, are not quite at the threshold for an El Niño Watch.

PIC OF THE WEEK:


Random little European town #1276-B. THAT'S where I want to take the family this summer for our summer vacation. I've set up a GoFundMe account if you'd like to donate.

Keep Surfing,

Michael W. Glenn
Phenom
Just Missed Time Magazine's 100 Most Influential at #101
International Bro, Brah, & Bruh