Hi All
Our good friend Trekker reminded me last night of some very useful information regarding typhoon wind speeds and damage assessment that I though I would pass on.
In the Northern Hemisphere, Typhoons rotate in a Counter Clockwise Direction, so the actual wind on the ground has to be factored with the speed of travel of the typhoon itself. The faster the speed over ground of the typhoon, the more wind that will be added or subtracted over the ground depending on what position within the circulation a specific point is.
To illustrate
Typhoon is travelling East to West at 15 knots with wind speeds of 150 knots.
Because of the counter clockwise rotation, the actual winds North of the track will be wind-speed + the speed over ground of the typhoon, in our example, 150 + 15 = 165 knots
On the south side of the track, it will be the reverse as we subtract the travel of the typhoon from the wind speed as it is travelling "with" the typhoon, in our example 150 - 15 = 135 knots.
Now this may seem insignificant, but realize that the difference between the north side of the track and south side is actually 30 knots. This can make a significant difference in damage assessment.
The strongest adjustments will be at 90 degrees to each side of the track with no adjustment on the actual track location itself, and proportionally in between the two positions.
The Southern hemisphere is simply the reverse.
When prioritizing mapping efforts, the initial areas to focus on would be 90 degrees to the north of the track in the Northern hemisphere and 90 degrees south of track in the Southern Hemisphere to look for the areas with the most likely damage
The faster the typhoon is travelling over the ground, the greater this effect is.
Our good friend Trekker reminded me last night of some very useful information regarding typhoon wind speeds and damage assessment that I though I would pass on.
In the Northern Hemisphere, Typhoons rotate in a Counter Clockwise Direction, so the actual wind on the ground has to be factored with the speed of travel of the typhoon itself. The faster the speed over ground of the typhoon, the more wind that will be added or subtracted over the ground depending on what position within the circulation a specific point is.
To illustrate
Typhoon is travelling East to West at 15 knots with wind speeds of 150 knots.
Because of the counter clockwise rotation, the actual winds North of the track will be wind-speed + the speed over ground of the typhoon, in our example, 150 + 15 = 165 knots
On the south side of the track, it will be the reverse as we subtract the travel of the typhoon from the wind speed as it is travelling "with" the typhoon, in our example 150 - 15 = 135 knots.
Now this may seem insignificant, but realize that the difference between the north side of the track and south side is actually 30 knots. This can make a significant difference in damage assessment.
The strongest adjustments will be at 90 degrees to each side of the track with no adjustment on the actual track location itself, and proportionally in between the two positions.
The Southern hemisphere is simply the reverse.
When prioritizing mapping efforts, the initial areas to focus on would be 90 degrees to the north of the track in the Northern hemisphere and 90 degrees south of track in the Southern Hemisphere to look for the areas with the most likely damage
The faster the typhoon is travelling over the ground, the greater this effect is.
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