If you know of some quality weather stations that aren’t yet in WindAlert: email us the name, location, and URL where the data resides. Thanks!

First off here is the NWS forecasts for the winds today:

And… here is what really happened:

Summary:

On these post frontal days when there is a very weak Westerly anticipated.   I always look for a signature “kink” in the isobars on the models over Cape Cod.    Models are getting better at this because 10 years ago they didn’t even show the kink.  Still they just don’t seem to lock in on the dynamics of the “canal trough” that develops and results in surprisingly strong WSW flow into southern Cape Cod and southern RI waters.

Here was our forecast for today:

A transitional day here as high pressure surges in from the south and Low pressure slips away to the north but sometimes these days can have some surprising winds.

• Keeping it conservative here as confidence on the afternoon cloud cover is low. However, if we see full sunshine we could see a stronger evening push to the east on the WSW flow.

• All areas should see gains through midday on gusty West then WSW winds and gusts may push mid teens at times.

• The real focus should come into evening as the WSW flow kicks in. Watch trends at BB Buoy and the islands as the flow should come on south to north and touches into the southern beaches evening hours. Chance it could push some solid upper teens.

In the top image find the huge storm west of Washington and note its counter-clockwise spinning winds and the 30-40 knot southerly winds hitting the WA coast. The models insist that it will not hit The Gorge but rather follow a trajectory to the NE as shown by the white arrow.

Still… why should you care? Answer… Look at the 2nd image and notice the SW storm winds hitting Cape Mendocino north of the Bay Area. Now find the North Pacific High SW of the Bay Area. Notice how it’s isobars and NW wind are compacted south of the Bay Area. Our forecast is betting that the storm follows the models trajectory and head more northward. That will allow the North Pacific High and its NW winds to move northward to at least the latitude of Waddell and the Peninsula.

If the storm stalls in position the North Pacific High’s surface NW winds will be stuck south of Waddell wrecking our forecast.

Now to wind a free night at a Gorge Vacation house over looking 5 launch sites answer these questions:

1. Why don’t we see NW clearing winds most of the winter.

2. Why do NW clearing winds become more common in the spring.

3. Why are they so rare mid summer.

Send your answer to mike@iwindsurf.com

Well after a lot of investigation and consultation between West Coast meteorologists Mike Godsey and Benjamin Miller here’s what was found:

First, the upper-level pattern is unusual for September with a weak cut-off low slowly churning over California and retrograding (moving westward) to a position almost over the Central Coast.

This has created large-scale southerly flow for southern California and the Central Coast, but it kept mild northerly flow intact for far northern California and the offshore waters beyond the buoys. These converging winds created a mesoscale eddy off the San Francisco Bay.

With a counter-clockwise spinning large eddy in the ocean to our west throwing south wind at the Golden Gate something still needed to draw this wind through the Golden Gate. Here’s were it really got interesting. A local surface low (probably leftover from the heat wave earlier in the week) just so happened to be over the far East Bay hills. This worked to create a local pressure gradient over the Central Bay and to draw the southerly winds from off the ocean through the Golden Gate and inside the Bay. Since the low was over the East Bay hills not much wind was reaching Sherman Island at the time. Then to really seal to deal, a weak eddy-like clockwise circulation got going over the Peninsula waters of the South Bay. This helped to make winds more W than SW at Treasure Island and it really favored Berkeley over Pt. Isabel.

***DISCLAMER*** Under no circumstances should you forget the respect that Mother Nature demands.  Know your limits, stay cautious and realize that tropical systems are notorious for the unexpected.

The validity of analyzing historical data in hopes of gaining insight for current tropical systems is on the questionable side.  The expected strength and track of Irene correlates nicely with what occurred during Hurricane Floyd.  Floyd almost made Cat 5 status at its strongest point while Irene is CURRENTLY EXPECTED to top out as a Cat 3 hurricane.  Floyd made landfall as a Cat 2 hurricane and Irene is expected to make landfall as a Cat 2 as well.

We can use this correlation in a general way to provide hints on what to anticipate as Irene makes land fall, but Irene is her own storm and still may have a few curve balls up her sleeve.  The synoptic setup for Irene and Floyd is as similar as it is different, so it would be unwise to let the apparent peak strength difference lull you into a false sense of security.

Please read this historical examination of Floyd even if you remember the storm well.  This examination is especially important if you did not get the chance to enjoy Floyd.  http://www4.ncsu.edu/~nwsfo/storage/cases/19990915/

The chance still exists for Irene to bounce back over the Atlantic after making landfall in NC.  This could allow her to stay stronger longer than Floyd and or let her strengthen again as she moves over open ocean waters with temperatures that are most likely warmer than those found in 1999 for Floyd.  I don’t have time to check ocean temps from 99 and the warmer temps are not necessarily due to global warming;)

If Irene tracks over land as CURRENTLY EXPECTED, it will weaken but keep enough energy to sustain Cat 1 hurricane strength until at least NJ / NY.  Floyd weakened to tropical storm strength as it passed over coastal MD and DE.  This is the one hundred thousand dollar question… It is possible that Irene will weaken to tropical storm strength over MD and DE just as Floyd did?  Only time will tell, and if it does weaken quicker than currently expected, this will be good news for those of us wanting to get a session in with Irene.

For those of you in NJ and northward, the possibility of a more rapidly weakening Irene will be a good go or no go indicator.  Remember to check our real time wind data at areas and sites south of where you are planning to go out.  This will give you hints at what may be coming your way.  In general, the strongest winds are always close to the hurricane storm center and get weaker the further you get from center.

Use our real time wind data in between NHC updates.  Plan for the unexpected and have a solid back up plan if things start to get nasty / not go as expected.

Stay tuned to your favorite WindAlert / WeatherFlow product.  We’ll keep you up to date with the latest developments concerning Irene so you can make well informed decisions to not only stay safe, but have the time of your life.

Enjoy!

***DISCLAMER*** Under no circumstances should you forget the respect that Mother Nature demands.  Know your limits, stay alert and watch trends.  Realize that tropical systems are notorious for the unexpected.  Have fun, be smart and enjoy all the washings / walks of shame that Ms. Atlantic can dish out.  If you’re not falling… you’re not pushing;)  Avoid giving any cops, firefighters and or lifeguards a hard time if they try to keep you out of the water.  It’s always easy enough to outflank them and get your session in.

The NHC, NWS and NOAA are public safety administrations which therefore demands that they err on the side of caution.  This fact, and some models and maps suggest that their current 5 day forecast cone for storm center is possibly closer to the east coast than Hurricane Irene’s track will actually end up to be.  (Note:  Irene will almost certainly clip OBX, it’s where she goes after clipping OBX that is still up for interpretation.)

It is reasonable to postulate that Irene’s track could swing farther E away from the east coast than currently expected.  Please see picture below.

Irene has a good chance to track along the eastern most border of the cone found above after clipping OBX.  Again, this is no guarantee.  Please stay tuned to WindAlert’s daily wind forecasts and any and all advisories from public safety administrations.

Timing is everything with these tropical systems and making smart decisions on where and when to get a session in is crucial for safety and avoiding frustrations.  You might consider a road trip to position yourself favorably for the type of conditions you are interested in experiencing.

If Hurricane Irene does end up taking a track that is along the western edge of the cone, you may consider inland lakes as alternatives to good old Ms. Atlantic and coastal bays.  A good way to explore the possibilities available to you is to read WindAlert’s forecasts for other areas other than those you typically frequent.

If your planning on waiting until Irene is N / NE of your area, please realize that these systems tend to accelerate away relatively swiftly.  This fact can have blasting winds fade off ridiculously quickly so give this some thought when selecting where and when to get some water time in.

We here at WindAlert pride ourselves in providing the most accurate wind forecasts available.  If we’re good enough to be the sole provider of wind forecasts and real time wind data for the upcoming America’s Cup, you can bet we’re as on top of Hurricane Irene as can possibly be expected.

Don’t forget about Thurs the 25^th as the majority of forecast areas from OBX to MA look to get a good prefrontal blow.  Heads up for the threat of approaching showers and or thunderstorms…  Favor the morning over the afternoon for the most user friendly conditions.

Enjoy Hurricane Irene, cuz we certainly will!

These systems are always a bit of a double edged sword. As avid watermen we all enjoy the super rare wind strengths and wave heights that these systems can induce. At the same time, we are concerned for the well being of those in the cross hairs of dangerous systems like these.

Take a look at the projected track of 2011 Hurricane Irene and the historical track for Hurricane Floyd from 1999.

To find the eddy first locate the Golden Gate which is about 1/3 of the way down the middle of the image. Then traverse your eye NW towards Pt. Reyes which juts out into the pacific. Now look in the ocean area between Pt. Reyes and the  Golden Gate.  You will see a counter-clockwise spinning eddy in this area. Notice how the eddy throws southerly wind at the Half Moon Bay to Bodega region and inside the bay.  There is actually a secondary eddy near Bodega.

Now look west of the eddy and notice the NW flow of clouds. This is the North Pacific High’s surface NW winds west of the ocean buoys. Now if the eddy would just disappear we would have typical summer winds. What is making this eddy? It is a combo of slightly NNW winds over the ocean and a nagging low pressure west of Redding. Why is this happening so often this summer? Basically the North Pacific High is centered towards the Gulf of Alaska rather than west of Oregon.

Win a valuable vacation prize! Why has the Gorge had much weaker winds than normal this summer? Send your answer to mike@iwindsurf.com