METEOROLOGY – EVERE WEATHER & TORM CALCULATOR
Flash Flood Guidance
A precise tool.
What is the Flash Flood Guidance & How does it work?
Flash floods occur when the ground is saturated and excess rainfall cannot be absorbed into the soil, leading to rapid runoff.
The Flash Flood Guidance (FFG) helps estimate the amount of rainfall that could lead to flash flooding based on soil saturation conditions.
The Flash Flood Guidance (FFG) helps estimate the amount of rainfall that could lead to flash flooding based on soil saturation conditions.
FFG = frac{R_{max} – R_{sat}}{C}
FFG = Flash Flood Guidance, R_{max} = Maximum rainfall capacity of the soil, R_{sat} = Current saturation level of the soil, C = Coefficient representing runoff efficiency.
Parameters
Result
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Frequently Asked Questions
What is Flash Flood Guidance?
Flash Flood Guidance is a tool that estimates how much additional rainfall could lead to flash flooding based on current soil conditions.
How do I use the Flash Flood Guidance calculator?
Enter the maximum rainfall capacity of the soil, the current saturation level, and the runoff efficiency coefficient into the calculator to get the FFG value.
What does R_max represent in the Flash Flood Guidance formula?
R_max represents the maximum amount of rainfall that the soil can hold before it becomes saturated.
Why is C important in the Flash Flood Guidance calculation?
C, the runoff efficiency coefficient, accounts for how effectively water moves across the land and contributes to flash flooding.
Can Flash Flood Guidance predict when a flash flood will occur?
While FFG helps estimate potential flash flooding based on soil conditions, it does not predict exact times or locations of floods.
What should I do if the Flash Flood Guidance value is high?
If the FFG value is high, be cautious and monitor for signs of flash flooding, especially after heavy rainfall.
How does soil type affect Flash Flood Guidance?
Soil type affects R_max and runoff efficiency (C), as different soils have varying capacities to absorb water and different rates of runoff.
Results are for informational purposes only and do not constitute professional advice.