Sea level forecasts are required for shipping in the area of the German Bight and the tidally influenced rivers Ems, Weser and Elbe. However, sea level forecasts also play an important role in tourism, shore side industry and agriculture.
Preparation of daily water level forecasts
A sea level forecast comprises the approaching four high or low water events at 16 specified locations along the German Bight and in the tidally influeced rivers Ems, Weser and Elbe.
- Lighthouse, Alte Weser
Forecast of the approaching high and low waters are expressed as a deviation from the mean high water (MHW) or mean low water (MLW) together with the respective entry times.
The forecasts are based on:
- Tidal predictions,
- Sea level observations (North Sea coast and rivers),
- Wind measurements in real time,
- Current wind forecasts/model results from the German Weather Service,
- Personal weather advice on site by the meteorologist on duty at the German Weather Service,
- Predictions from the operational model of the BSH,
- Curve predictions using the MOS (Model Output Statistics) method.
The forecast, taking into account all available information, is prepared by the scientist on duty. It is performed four times a day - at 01:00, 08:00, 14:00 and 20:00.
Distribution of Information
The forecasts are sent by fax or FTP download to the responsible authorities, traffic control centres, port authorities, and radio broadcasting stations. In addition, all predictions are published in the internet at www.bsh.de. Beyond the scientific forecasts for high or low waters, forecasted curves produced by the MOS procedure are displayed for 32 sea-level stations.
Storm surge warning service
In the event of a storm surge, the forecast service is available around the clock and can be reached by telephone at +49 40 3190-3190.
What is a storm surge?
For a storm surge to occur at the German North Sea Coast, three factors are cruical:
- Gale force winds from northwesterly directions,
- Coinciding timing of high wins and rising or high water,
- Minimum water level of 1.5 m above mean high water.
If extreme high and low waters are to be expected, shipping, ports, companies and people living on the coast are warned at an early stage. From a water level higher than 1.5 m above mean high water (MHW), additional storm surge warnings are issued.
- from 1.5 m above MHW = storm surge
- from 2.5 m above MHW = severe storm surge
- from 3.5 m above MHW = very severe storm surge
The storm surge warnings are distributed through following channels:
- Internet at www.bsh.de
- Per Fax an die zuständigen Behörden
- FTP download
- Warnings through radio broadcasting
- WarnWetterApp of the German Weather Service
- Fee-based, automated telephone warning (FACT 24)
The fee-based FACT 24 system provides warnings to interested parties from a water level of 0.75 m above mean high water or 0.75 m below mean low water.
Phone: +49 40 3190-3190
Fax: +49 40 3190-5032
Monday to Friday: 07:00 – 00:30
Weekends and public holidays: 07:00 – 13:30 Uhr and 18:00 – 00:30
In case of storm surges: around the clock