How to quickly model the effects of a sea-based storm

In ememergency situations or conditions it can be both useful and important to quickly set up a calculation model for broad-strokes consequences. This can include situations in which a huricane or other sea-based storm quickly imposes large amounts of water on a coastal area.

How to quickly model the effects of a sea-based storm:

1. Generate a Project for the to-be-affected location. Ensure the size is commensurate with the size of the storm.
   Note that for quicker calculations a Basic Mode project is recommended.
2. Ensure auto-calculate for the Project is off
3. Use Areas → Add Complete Map Area, to add an Area for setting the sea Water level.
4. Set the WATER_LEVEL Attribute of the Area to the expected sea-level.
5. Add a Rainfall Overlay, and open its Configuration Wizard.
6. In the Rain Event step, rename the currently selecter weather to "Storm".
7. For the rainfall, enter the parameters of the storm to be calculated (the duration of the rain event and the amount of rain to fall in that period).
8. Add another weather, and rename it to "Storm Short".
9. Enter the same parameters for rainfall, but divide the time and amount of rain by 10. Keep the short storm selecter.
10. In the Timeframes step further in the Configuration Wizard, set the amount of timeframes to a reasonable amount. 20 or 30 is proper in most cases.
11. Recalculate the Project. Verify that the calculation time is reasonable, and would also be fine when multiplied by 10. Verify that some results are produced.
12. Reopen the configuration wizard, and set the weather event to the proper Storm.
13. In the Output Overlays step, select the results which may be of interest. Consider: surface last value, surface avg direction, surface flow, impacted buildings, and flood arival time.
14. Recalculate the Project again, whcih by setting the storm to the full event will now give a simulation of the full storm.
15. Once complete, inspect the results.

• 
  A simple and linear but very heavy rainfall event.
• 
  Excess water exists in many places on the map, but certain coastal areas are significantly hit.

Notes

• This approach is sufficient for a quick indication of affected areas, but also inherently makes very broad assumptions. Care must be taken when interpreting the results.

See also

• Rainfall Overlay
• Flooding Overlay