# How does lifetime of a cyclone affect: precipitation and intensity

1. May 2, 2018

### Imolopa

When the total lifetime of an extratropical cyclone over the ocean in the Northern Atlantic-region gets longer (within the same season):
- Do the total precipitation sums increase?
- Does the precipitation intensities increase?
- Does the intensity of the cyclone increase?

For example what would be the differences between a cyclone that lasts one or two days in total in winter versus a cyclone that lasts nine days in total in winter (both over water)?

Any reliable research or research institution/organization that mention this/published research article mentioning/backing up this claim?

Last edited: May 2, 2018
2. May 2, 2018

### Staff: Mentor

I'm having trouble understanding your question (and your thread title). What do you mean by "lifetime" of a cyclone? Time over water (gaining energy) or time over land (losing energy)? Can you use "Sandy" as an example to illustrate your question? Thanks.

3. May 2, 2018

### Imolopa

Thanks for the input! I editted the main question now to make it clearer. Yes I mean time over water.

4. May 2, 2018

### rootone

For a typical cyclone or just any low pressure system really,
The total amount of precipitation it generates will be the result of many factors.
The amount of time it exists for will certainly be one of the most significant factors.
A cyclone which is producing say 5cm per day average rainfall is clearly going to produce more rainfall total if it lasts for ten days days than it will if it lasts for six days.

5. May 15, 2018

### johnbbahm

I think it is more complex than that, because the longer a cyclone lives the more it is also exposed to
things that can tear it apart.
From what I have seen precipitation intensities does not increase,
(thank goodness it is bad enough already). They calculated the possible rainfall totals for Hurricane Harvey,
the Friday before the storm moved over the Houston area, based on the speed of the storm.
100/speed of the storm in miles per hour=possible rainfall
In Harvey's case 100/2 miles per hour=50 inches of rain.
Technically I only measured 48 inches at my house, but there was some error in my measurements.
This same rule of thumb applies to storms that took 10 days to cross the Atlantic and Tropical storms that formed a few days before.