


Expect some fireworks at the ISAF Annual Meeting in Dun Laoghaire, Dublin, Ireland, November 1 - 11 when the Council will reconsider the decision to eliminate windsurfing. Meanwhile, the Petition to reinstate windsurfing as an Olympic Sport continues to collect more names.
Windsurfing defended · "The Last Word weighed the perennial political question: which is more elitist — windsurfing or dancing horses? It all started with FOX News conservative Charles Krauthammer, who took swipes at Mitt Romney for committing the political sin of sending his very expensive horse to the London Olympics. But one thing he thinks is still more elitist? John Kerry windsurfing. MSNBC's Lawrence O'Donnell dissected the folly in that logic in the latest Rewrite."
But on the other hand: "The Pryde Group, one of the world's biggest players in the marine and adventure sports markets, is proud to announce a partnership with Jaguar Cars and the all-new Jaguar XF Sportbrake. Jaguar will appear on sails, boards, buoys and rider lycras with local market activating the sponsorship in their respective countries.


The ridge axis was a term used in almost every forecast discussion in July. I asked Dr. Steven Lazarus from the Department of Marine and Environmental Systems at FIT and Scott Spratt from the NOAA Field office in Melbourne, FL a few questions about it:
Where would I find the current position of the ridge axis?


The ridge axis feature is important to the sea breeze. How does its location affect: onset and strength.
Dr. Lazarus: The large scale ridge does affect the strength of the sea breeze which is a mesoscale phenomenon. It's intensity and position will either enhance or reduce the sea breeze. All things being equal - if the ridge axis (E-W) pushes north of our area - the easterly flow in the clockwise circulation will increase (add on to) the sea breeze generated flow. Conversely, if the axis slides south we tend to get westerly surface flow and the sea breeze can be pinned up near the coast or not even penetrate inland whatsoever if the westerly flow is strong. In the former case, the enhanced sea breeze, may be overwhelmed by the large scale easterlies and be hard to identify. This is especially the case in the fall when the surface pressure gradient increases at our latitude. Remember - the winds blow in proportion to the pressure gradient. That is where the intensity of the high comes into play.
Spratt: While there are exceptions, in a general sense, when the axis of the ridge is nearly overhead, local winds are generally light, which allows the sea breeze to form earlier and become stronger. When the ridge is to your south, the large scale wind flow will be offshore (southwest or west winds), which tends to delay development of the sea breeze and slow its migration inland. If the ridge is far enough to our south (usually over the extreme southern peninsula or the keys), the large scale wind flow can be strong enough to totally restrict sea breeze development. When the ridge axis is to your north, the large scale flow will be onshore (east or southeast winds). If the axis is near or just north of the FL/GA line, the onshore flow will often be strong (breezy/windy), and can disrupt sea breeze formation or add only marginally to it (since the onshore flow is so strong already). When the large scale onshore flow is weaker, the sea breeze can still develop and reinforce the large scale onshore flow.
How does the ridge axis effect the development of thunderstorms?
Dr. Lazarus: See my comments above - the former case (enhanced easterlies) - thunderstorms tend to be more west coast located and vice-versa for the westerly flow and northward displacement of the ridge axis (east coast located). The sort of tweener case is the ridge axis over head - ideally that suggests that the winds are primarily sea breeze generated - in this case inland thunderstorms tend to dominate. Keep in mind that this is all idealized...Once thunderstorms develop - things get complicated quickly!
Where do sea breezes originate? Are they broadly located along coastal waters offshore or is there a more localized point of development?

So, by knowing the location of the ridge axis, you can make some general assumptions on when the sea breeze will develop and how strong it will become. The local forecast models also typically do a pretty good job with the strength of the sea breeze (especially the higher resolution model) -- so you can take a look at them and use them to help you make a local wind forecast.
A few knots more of wind can make all the difference for us windsurfers. Is there anyway to predict the strength of a sea breeze?
Dr. Lazarus: In terms of predicting the intensity of a sea breeze circulation - there are some simple analytic models that are a function of the difference between water temperature and land temperature. So from a simple/climatological standpoint - these are good predictors. Hence, sea breeze intensity tends to peak here in early summer (May/June) and then diminishes late summer (Sept/Oct) as the ocean continues to warm while the land is cooling thereby a diminishing temperature differential. Because our summer flow here is a combo of the large scale ridge and mesoscale sea breeze - it is not a simple answer. However the high resolution models (NAM, RUC) are getting pretty close to resolving the sea breeze circulation - so I recommend looking at their output.
Spratt: Precipitable Water (PW) does not impact the sea breeze, but does have significant impacts on whether thunderstorms develop along the sea breeze boundary as it develops and shifts inland. We have a summary on our web site which describes how the location of the ridge axis determines the prevailing wind flow (this is the large scale component of the wind, NOT taking into account local sea breezes). The prevailing wind flow also dictates the lightning storm coverage pattern for the day. The lightning storm pattern assumes "average" PW values for the given prevailing wind flow. If the PW on an individual day is higher than "average", there likely will be a greater coverage of storms, whereas a lower than "average" PW likely would mean a lower coverage of storms. Check out this web page on Lightning Threat.
Any more help for us wind junkies with anything about the sea breeze?
Dr. Lazarus: You can sign up at the UCAR Comet Met-Ed module site, log in and take their online sea breeze tutorial. I frequently assign these to my students and they are quite good! Some other sites that may also help - but not as good as the Comet module: Sea breeze from the U. of Illinois and NOAA Tutorial: Sea breeze.
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