This is a sample forecast for a Sailing Race in the Bahamas.
WeatherFlow Forecast for Farr 40 Worlds 2002
Race Forecast issued by WeatherFlow Meteorologist David Morris commissioned by North Sails & Sailing Weather Services.
Issued: Wednesday – 11/13/2002 06:00 (EST)
All times are referenced to local time. All directions are referenced to True North
Synopsis: The weather maps this morning show a vigorous cold front extending from Nova Scotia through to Southern Florida and continuing to sweep to the south and west of Cuba. It is this feature that will dominate the weather today, and the forecast hinges upon the exact timing as it propagates in from the northwest. To complicate matters a well defined pre-frontal trough is running ahead of the front itself and currently lies across The Bahamas. Ahead of the system warm, mainly southerly winds are flowing across the region with bands of convection spilling across the islands. Behind the cold front there exists a relatively tight pressure gradient, generating blustery and gusty northwesterly flow. Models are tending to agree on the timing of this system, placing the cold front itself across the race area around 1pm.
Current Conditions: Satellite imagery this morning shows a band of cumulonimbus cells along the pre-frontal trough, aligned NE to SW across the islands. A major cell is currently tracking eastwards from Great Abaco Island and blossoming across the NE Providence Channel. Two other cells are flourishing and merging just to the south of Nassau and over Andros Island, as they track eastwards towards Eleuthera Island. Other bands of cloud lie across Florida and the Florida Straits. Currently these are less active but show potential to flourish and track towards the race area.
Nassau Airport reported thundery activity overnight with mainly light and variable winds less than 10 knots. In the last hour southerly breezes at 6 knots have filled in. Georgetown, Exuma has held on to light E and ESE flow in the 4 to 8 knot range. Freeport, Grand Bahama saw diminishing S and SW flow overnight in the single digits, becoming calm this morning, with thunderstorms nearby. Settlement Point, Grand Bahama, also reported diminishing SSW and SW winds in the 10 to 14 knot range overnight, and is currently reporting SSW at 10 knots.
The Florida Keys continue to see light southerly flow in the single digits. West Palm Beach reports westerly flow in the 8 to 12 knot range. Post cold frontal winds have filled in at the NASA shuttle facility, Cape Canaveral and the St. Augustine Buoy. Both are reporting strong NW winds around 25 knots gusting to the low thirties.
Forecast Discussion: Relatively light ambient winds through the morning hours with perhaps some rejuvenated heavy shower and thunderstorm activity generating gusty and fluky conditions. More consistent, light southerly flow should fill in once the cells to the east have tracked a good distance away. Average strengths in the 8-12 knot range, rising to 11-15 with a few spotty upper teen surges possible towards midday. Also, average ambient directions will tend to veer to the SW and even WSW around midday, barring any new localized thunderstorm development.
Tricky conditions through the early afternoon as the front closes in. There is a good chance that bands of convection will once again fire up. Towering Cu and developing Cb would generate stronger veered gusts ahead of them. Potential exists for some quite severe gust fronts to set up throughout the region. Eventually ambient directions veer to W and WNW with more solid flow trying to fill in. Through the late afternoon NW winds become stronger with potential for late day gusts into the upper twenties, although these stronger winds may not actually come to fruition until after dark.
Weather: A mix of cumulus and stratocumulus, with cumulonimbus clouds embedded within the flow. Watch for localized heavy shower and thunderstorm development. May see an occasional funnel cloud extending down from some of the darker cloud bases.
Maximum Temperature: Around 81F.
Seas: Confused seas. Building to 2 to 6 ft.
Detailed Wind Forecast for Today (11/13/2002):
|Time (EST)||Dir Mean||Dir Range||Speed Mean||Speed Range||Comments|
Hedge: 1) The forecast discussion and table largely describe the larger scale ambient flow around the front as it tracks through the region. However, localized conditions are likely to vary from these overall speeds and directions. New cumulonimbus development may be difficult to observe if it is embedded within a lower deck of stratocu. Watch for considerably stronger, veered gusts ahead of the cells and extended periods of light and variable conditions in their wake. Most of the gusts are expected to be right shifts reflecting the stronger veered flow aloft, however localized conditions could easily generate occasional left shifts.
2) Small scale localized variations may generate conditions that vary from the table considerably. Frontal timing is also key. If the front tracks through a little quicker than models suggest, we can expect earlier and stronger northwest winds to fill in by late afternoon. Conversely, if the front tends to stall out, later and weaker northwest winds would fill in. However, the latest models appear remain in good agreement.
Outlook for Tomorrow: Cooler, post cold frontal northerly winds fill in across the region as tighter pressure gradients surge across The Bahamas in the wake of this vigorous system. Weakening high pressure slides southwards from The Carolinas into Northern Florida and offshore into the Atlantic. This results in veering and diminishing winds through the afternoon hours. Likely to see plenty of residual cloud early on, even with the chance of a few residual showers through the morning. However, a clearing trend characterizes weather through the afternoon.
Detailed Wind Forecast for Tomorrow (11/14/2002):
|Time (EST)||Dir Mean||Dir Range||Speed Mean||Speed Range||Comments|
Subject: Good job!
Date: Thu, 14 Nov 2002 04:09:04 +0000
13 November 2002. The first day of the Rolex Farr 40 World Championship began with sunny skies and a light breeze. The weather fax provided daily courtesy of North Sails, one of the sponsors of this event, called for light winds through the morning hours with the winds increasing in strength throughout the day and it was pretty accurate. The first race of the day was delayed for a half an hour while the race committee waited for the breeze to fill in. By the start of the first race, the breeze had increased to 12-14 knots and continued to build. Defiant was first around the top mark and held on to that lead to win the first race. They were followed by Bottadiculo in second, a new Italian boat owned by Giovanni Arrivabene and Raffaele Mincione and just recently launched by Carroll Marine. Next came Norwegian Steam followed by Steam who has two Bahamians on board with Virago in fourth. Breeze, helmed by Vincenzo Onorato who rushed out of New Zealand after being eliminated from the America’s Cup in order to make the Rolex Farr 40 World Championship in time, came in fifth.
The second race started in about 20 knots of breeze and began as a straightforward race but ended up as anything but. Defiant was again the first boat to the top mark with about a 20 second lead. Half way through the race a huge rain squall came through and suddenly there was no visibility out on the course. A couple of boats ripped chutes and several others either had dramatic broaches or had to throw in last minute gybes. Nerone and Defiant came flying down the last leg with the rest of the fleet close behind. Nerone maintained their lead to cross first. Le Renard and Barking Mad snuck in to finish second and third resectively and Defiant ended up on fourth.