Pressure in storms

[chargurl]

I could b postin wrong place but, is there a graph or link of what pressure equals approximately what strength storm or hurricane?
Like: 990=Ts or 970= cat ?,

Thank you!

[pojo]

mb doesn't associate with a specific category on the SS scale. The winds actually determine the scale strength and from there, that's where they determine the category.

[chargurl]

Thank you! I c the models with estimated pressures and didn't know if that was or wasn't indicative of strength in a storm.

[thetruesms]

There is a loose correlation between winds and central pressure, but absolute pressure values technically do not determine wind speeds. It is the pressure gradient - the difference in pressure over space - that determines the strength of the wind. However, the lower your minimum pressure, the more likely it is that you will have a strong pressure gradient.

[supercane]

The original version of the Saffir-Simpson scale did have approximate surge and pressures assigned to each category as shown below:

However, as noted above, wind speeds do not correspond perfectly with pressure or storm surge. Here is an image from Avila's presentation at this year's hurricane conference. While there is a general inverse correlation between wind speed and pressure, there is also a lot of variability between storms:

Because of this, the NHC decided to decouple storm surge and pressure from the scale.

[Aslkahuna]

For years, JTWC has used a wind/pressure relationship that they developed. They still tend to use it on storms with no recon (which is most of them) but in recent years they have wandered from it particularly with off season storms. To demonstrate the point about gradient. STY Tip with 870 mb was a gorilla of a storm-the largest ever seen. STY Rita in 1978 was at 878 mb and about the size of Andrew. Tip is carried at 165 kt maximum winds while Rita is at 155kt yet it could easily be likely that Tip was even weaker wind wise than Rita because the gradient was spread out. As it is, some other storms have been considered as being stronger than Tip based upon their Dvoraks and they were smaller in size than Tip.

Steve