Everyone remain calm.
SURF:
While the East Coast has been getting record surf from record hurricanes, us lil’ ol’ West Coasters have been getting skunked. Sure we’ve had little S swells that have given the OC chest high waves off and on the past month, but it’s been few and far between down here. Throw in some cool water temps and showers (gasp!) and you’d think it was fall! Well I guess it is fall, but that’s beside the point. It’s been pretty small with unappealing conditions and it won’t get much better this weekend.
On tap for tomorrow is a NW windswell/groundswell that is peaking tonight (just our luck) from the cold front that blew through today. Look for chest high surf in the AM. Then it drops during the day as the W winds pick up too for breezy conditions. By Saturday, we’re back to waist to chest high waves and Sunday we have leftover waist high NW. So if you want something rideable this weekend, get on it asap! High pressure should set up by Sunday though and we may have great beach weather- just no real surf.
Water temps as mentioned above are hovering in the mid to high 60’s and tides this weekend are 2’ at sunrise, up to 5’ just before noon, and down to 2 at sunset. And if you haven’t noticed lately, sunrise and sunset are around 7 AM/PM each day. Easy to remember, huh?
FORECAST:
After the peaking NW on Friday, we’ve got… not much to report. Again- no major storms in the Pacific have been aimed our way the past few days so no real surf next week. Just look for background S/NW for waist high sets. But the weather should be nice. At least we have that going for us. And in the long term- nothing else to report through at least next weekend. Best case is a hurricane to form or a storm in the Aleutians to form so we can get surf in early October! If anything changes between now and then, keep up to date on the waves and weather at Twitter/North County Surf.
WEATHER:
Perfect timing for the showers today- the first full day of fall. The low pressure that dropped a few hundredths of an inch in southern California will hang around through Saturday morning, then high pressure starts to fill in Sunday. Most of next week should have mild Santa Ana conditions for light offshores in the AM with temps at the beaches in the high 70’s. Wouldn’t it be awesome if we had some surf to go along with that sunshine?! Do I sound bitter? I’m not.
BEST BET:
Friday morning while we still have leftover NW and the winds haven't picked up yet!
NEWS OF THE WEEK:
What happened to our El Nino of years past with all the great weather, warm water, and surf we should be expecting this time of year?! Seems like it’s been flat forever, cooler than average (definitely for an Indian Summer), and the East Coast has been getting all the surf- which is odd since it should be flat during an El Nino over there.
Well… the equatorial Pacific has been cooler than average (just east of Hawaii) and the signs are now pointing to NOT an El Nino but rather… the dreaded La Nina this fall/winter. Here’s the National Ocean and Atmospheric Administration to explain:
The September El Nino/La Nina forecast is out and forecasters think there is an approximate 55-60% chance of La Niña this fall and winter. We are officially on a La Niña Watch. Here’s the latest developments:
Summer Summary
First, though, a quick recap of current conditions in the tropical Pacific Ocean. The sea surface temperature in our favorite Niño3.4 region in the central Pacific was about 0.1°C colder than the long-term average over June – August, smack-dab in the neutral range. The atmosphere also reflected neutral conditions during the summer, with the winds above the equatorial Pacific neither particularly enhanced nor weakened, and an average pattern in the clouds and rainfall.
While neutral prevailed during meteorological summer (what we call June – August, while the summer solstice through the vernal equinox is “astronomical summer”), we began to see some indications over the course of August that a change may be afoot. The first of these is the downward trend in central Pacific sea surface temperature anomalies (departure from the long-term mean) from July into August, with the August average in the Nino3.4 region of about -0.4°C.
Winds and Waves
One of the many environmental factors that we monitor closely is the temperature of the tropical Pacific below the surface of the ocean. Over the course of a couple of months, areas of cooler or warmer water can grow or move below the surface of the Pacific from west to east along the equator. These blobs (often in the form of oceanic Kelvin waves) often rise to the surface as they approach the eastern Pacific Ocean, and so give us a heads-up of how the surface may look in the near future. It just so happens that during August, an area of cooler-than-average water developed around 50-150 meters below the surface of the Pacific.
Subsurface Kelvin waves are triggered by changes in the wind at the surface. The trade winds normally blow from east to west across the surface of the equatorial Pacific, keeping warmer surface water trapped in the western Pacific Ocean. If the winds weaken or strengthen, they can sometimes—but not always; this is a complex system—kick off Kelvin waves. In the case of an upwelling Kelvin wave, such as what we saw over the last month, the winds across the equatorial Pacific have strengthened, pushing harder on the surface waters and allowing cooler water to upwell from the deep ocean.
Since fall of 2016, the overall wind pattern has tended toward slightly stronger-than-average trade winds in the central and western Pacific, with a brief interruption in April 2017. This pattern is a little La Niña-ish, despite a lack of cool sea surface waters, and it’s one of the reasons we didn’t have a lot of confidence this past spring in the climate model forecasts for El Niño.
During the second half of July, the trade winds puffed a bit harder over the western half of the Pacific, likely helping this current Kelvin wave form. The complexity of the ocean-atmosphere system, where changes in one feed back into the other, means it’s difficult to diagnose a “cause” of the strengthened trade winds.
Model Citizen
The other major factor playing into forecasters’ consensus that conditions are favorable for the development of El Niño or La Niña conditions within the next six months (the criteria for a La Niña Watch) are the forecasts from the dynamical computer models.
The ensemble of models from the North American Multi-Model Ensemble (NMME) is predicting that La Niña will develop this fall, and last just through the winter. Back-to-back La Niña winters are not uncommon, and have occurred at least five times since 1950, most recently in 2010-2011 and 2011-2012.
We are giving credence to the model forecasts because there is supporting physical evidence (that subsurface cooler water I was going on about a few paragraphs ago) and because September forecasts of Niño3.4 sea surface temperature have historically been fairly accurate.
After analyzing 36 years of predictions from the NMME, we found that September forecasts for November Niño3.4 sea surface temperatures have a strong relationship with what actually happened (0.96 correlation value, where 1.0 means they follow exactly). So, while they’re not perfect- they’re usually reliable.
Watch On
In short, forecasters think that the sea surface in the Niño3.4 region will continue to cool, and the atmosphere will respond with a strengthened Walker circulation—the characteristics of La Niña. While chances of La Niña do have the edge in the current forecast, the odds only top out at about 60% likelihood that La Niña conditions will prevail in the winter. Climate forecasters will take this into consideration when developing the forecast for this coming winter, which will be released in October.
Long story short, if La Nina does form this fall/winter, it looks to be weak. So the forecast might be slightly less rain, slightly cooler than average water temps, and less/smaller surf. Makes you want to move to Lemoore, doesn’t it?
PIC OF THE WEEK:
Since we haven’t seen good surf since, well, since the Chargers were in San Diego, I thought I’d give you a little reminder.
Keep Surfing,
Michael W. Glenn
Magnificent
Voted Best DJ In Vegas
Lassoed A Bull Shark At Kelly’s Surf Ranch. Yeehaw!
