If you don't have a real weather buoy nearby, a Virtual Buoy is the next best
thing, or better in some ways. It is a wave model prediction of
a buoy report. Wave height, wave direction, wind speed, wind direction
and period are extracted from NOAA WAVEWATCHII model and displayed
like a buoy report. From the report, you are able to estimate the
current wind and swell conditions and get a seven day buoy report
forecast.
Virtual Buoys bring quality marine weather forecasts to remote
areas of the world. A global set of Virtual Buoys are freely available
on BuoyWeather as a public service. This is now a necessity! It
is the point specific forecast you need to safely plan your marine
activities.
Virtual Buoy's have three display options:
7 Day Graph V2 - Nowcast and 7 day text forecast with all of the data plotted in bar charts.
7 Day Graph - The free Virtual Buoy report. The graphs are made with HTML tables. A nice clean display we have used for several years. Loads fast.
Text Tables - Formatted text tables. Buoyweather subscribers
can receive this via daily email.
The forecasts go out at 6-hour intervals for 7 days. Both WAVEWATCHIII & GFS model update 4 times per day.
For the WAVEWATCHIII based forecast, there are six Ocean variables forecasted for each time:
Seas - The low number is the significant wave height provided by the model. The average of the highest 1/3 waves. This is an average and may not be the highest you'll see. The upper end of the range is 1.5 X significant height. This is closer to the largest swell you may encounter during the six hour forecast period. You should be prepared to deal with this if you are planning to go out.
Peak Period (seconds) - The interval between wave crests
measured in seconds. Large, short period (<12 sec) swells can mean
danger to a small craft. Long period swells mean opportunity for
surfers.
Peak Direction (degrees) - The direction of the peak period swell.
This is rarely the only swell present. There can be many swells
crossing a single point on the Ocean at the same time. The peak
direction shows the direction of the swell with the most energy.
Wind Speed and Direction - This gives you the overall wind
flow. For points near land, you may have to make further interpretation
to adjust for local topography and land/sea breezes. You will often
see the prevailing wind pattern in the graphs with light winds in
the morning and afternoon sea breezes.
Surf - Surf is what happens when swell hits shallow water
and breaks. For points near land, the swell height and period are
used to derive a surf height forecast. Useful if you are diving,
fishing, surfing, or navigating a pass. The surf range is the front
face heights in feet. It can be tough to make this conversion where
reefs, islands or points are blocking the swell. The logic works
like this. If a shoreline is exposed to the swell direction indicated,
you should see at least the lower end of the surf range. If a shoreline
is perfectly exposed to the swell direction indicated, you might
see the upper end of the range.
For more information about the WAVEWATCH model, check out NOAA/NCEP/OMB WAVEWATCHIII home page.
The GFS model provides data for land and sea areas. If you are
over land, in the Mediterranean or Red Sea, these are the forecasts
you need to to use. We have two meteogram files based on NOAA's
GFS model:
GFS & NAM Text - A text version of a meteogram suitable
for email. Plus it loads fast. This forecast can be very useful
whether in the tropics or in the mountains. Most of the variables
are self explanatory
LI stands for Lifted Index. Here is the general interpretation:
LI values greater than 0 mean thunderstorms are unlikely
LI values between 0 and -2 mean thunderstorms are possible
LI values between -3 and -5 mean thunderstorms are probable
LI values less than -5 mean a strong potential for severe thunderstorms
CP is the Convective Available Potential Energy(CAPE) divided by 100 to save space. Here is the general interpretation
for the numbers in this forecast:
CP values between 3 and 10 mean weak thunderstorm activity
CP values between 10 and 25 mean moderate thunderstorm activity
CP values between 25 and 53 mean strong thunderstorm activity
The T-STORM column reads the LI and CP for each time to determine the thunderstorm likeliness.