Flexible Reporting; Frequently Asked Questions

Can I customise my forecast report layout?

Yes, it is possible to customize report layout. Please reach out to offshore@meteogroup.com to customize your report layout as needed.

What type of elements am I able to add/modify?

Of the elements available, you can modify all of them. Units can be changed regarding wind speed and wave height; wind direction and visibility can also be changed to text mode instead of numbers. Wave information can have more detail such as TP/TZ, currents and different swell partitions. You can contact us for specific information.

What is the risk factor and how should I interpret that?

Risk is inserted as another layer to assess possible higher conditions. It stands for 90% of confidence that values will not exceed the risk value, or the other way, 10% of chance exist that values may exceed the risk value. For 10-meter wind speed it only shows up when the forecast above 22 knots and for wave height when it is above 1,5 meters.

 

RISK WIND SPEED

A nautical forecast may contain the element “Risk 10m wind speed”. It means that there is 90% confidence that wind speed at 10 metres height will not exceed this value. Whenever the value is 22 knots or more, it will be listed in the offshore products forecast table. For example: suppose the average wind speed is 22 knots and the risks are 25 knots at a specified time. This means we expect the wind speed to be 22 knots at the forecast location, with 90% confidence that it will not exceed 25 knots.For the computation of the risk wind speed, the following items are taken into consideration:

1. The usage of various models (ECMWF, ECMWF-ENS, NCEP-GFS, UKMO)

2. Spatial wind variations of the different models within a range of 100km

3. Timing differences of these models

4. The occurrence of thunderstorms

 

Basically, this means that different solutions (tracking) of weather systems are considered. Different timings and associated winds generated by those systems are reflected within the wind risk.

How to interpret the Risk Wind Speed:

 

1. The risk value applies to the 10m wind speed. Other wind speed parameters for example: . 50m wind speed and wind gusts will have a corresponding risk value, which can be calculated by applying the same ratio as between the risk wind and the 10m wind. For example: 10m wind speed is 24kts, risk wind speed is 30kts, 50m wind speed is 28kts. Then risk 50m wind speed is 28 x 30 / 24 kts = 35kts.

2. When there is a relatively large difference between 10m wind speed and risk wind speed, it means that there is an uncertainty in the forecast, therefore a low forecast confidence is indicated for that specified location and time. The risk value should be treated merely as an indication of what could also happen.

 

RISK WAVE HEIGHTS

A nautical forecast may contain the element “Risk (significant) wave height”. It means that there is 90% confidence, that the significant wave height will not exceed this value. Whenever the value is 1,5m or more, it will be listed in the offshore products forecast table.A similar explanation as provided above for risk wind speed is applicable to to risk wave height, with the following remarks:

1. The models that we particularly use for wave heights are ECMWF, ECWMF-ENS and NOAA-WW3.

2. Unlike risk wind speed, the risk wave height does not depend on the occurrence of thunderstorms. Enhanced winds near thunderstorms are usually short-lived, occurring locally without a strong effect on wave heights.

3. Risk wave height applies to significant wave height. The value indicates a 10% chance of exceedance. It is essentially different from maximum wave height, which is usually provided in the forecast. It denotes the upper limit for the height of a single wave. Nevertheless, the corresponding value for maximum wave height can be calculated by applying the same ratio as between the risk wave height and the significant wave height. For example: Hsig = 2.4m, Hrisk= 3.0m, Hmax = 4.0m. Then the indicated risk for Hmax is 4.0 x 3.0 / 2.4 m = 5.0m.

 

How should I interpret the weather codes on my forecasts?

Weather information in code (like SHRA - the abbreviation for Rain Showers) is a model technical value. Your forecast will indicate SHRA when the atmosphere would allow showers to develop according to the model data, but this does not necessarily have to happen at that specific point in time. It means that the atmosphere allows for rain showers to develop. This is different from wind/wave values which are intended to be representative for that forecasted point in time.

 

Can I add a point to the map referring my location?

Yes, that is possible. Map will lose its synoptical scale. The fronts will not be plotted but you will start to receive a close-up version with the marked location.
 

How does the MeteoGroup forecast engine work?

Our offshore forecast engine is called Nautical MeteoBase (NMB). NMB uses multiple sources of atmospheric and oceanographic model forecast data as input. These are the global and regional weather models as run by ECMWF, UKMO, NCEP/NOAA, KNMI. The regional models are high-resolution models. For longer forecast lead times, ECMWF ensemble model output data is also used. All data goes through the weather room who make last minute edits on the forecast based on the most recent observational data.

 

Can MeteoGroup’s offshore forecast engine be further customized to our site?


The raw NMB data can be modified through: a near-shore post-processing module (called Rose), automated local calibration using observations (with a Kalman filter), further manual interference by a meteorologist, who then also uses other data sources e.g. weather station and buoy observations, satellite and radar images

 

Want to learn more? Get in touch with us.

 

Contact Us