Charley pressure gradient

[hurricanetrack]

Ok- here's something to chew on:

During my Charley mission, as I just "discovered" tonight while looking over raw data from the missions, I noticed that the pressure was 1000.14 millibars at 4:01pm EDT while we were set up near Punta Gorda. At exactly 4:54pm- the pressure was 943.28 millibars! That's a 57 millibar drop in 53 minutes!

As Jesse said when I pointed this out to him tonight on the phone- "No wonder it was windy that day!"

[P.K.]

A slightly large PGF there then

[weatherwindow]

does anyone have the gradient in pressure drop per mile in the core of charley?....i understand that the labor day storm of 1935 had the record at 6 mb per mi..

[isobar]

Wow, that's an incredible pressure gradient. I would also be very interested for more info on the rate drop per mile in the core of Charley.

[James]

Actually, I would too. That is one steep pressure gradient!

[P.K.]

*Imagines having to draw hurricane on chart by hand*



At least you'd be able to get a good average PGF out of the chart though

[Stormsfury]

Ok- here's something to chew on:

During my Charley mission, as I just "discovered" tonight while looking over raw data from the missions, I noticed that the pressure was 1000.14 millibars at 4:01pm EDT while we were set up near Punta Gorda. At exactly 4:54pm- the pressure was 943.28 millibars! That's a 57 millibar drop in 53 minutes!

As Jesse said when I pointed this out to him tonight on the phone- "No wonder it was windy that day!"

Considering the FWD speed of Charley was roughly 20-21 MPH, let's say that in 53 minutes moved approx. 19 miles. It APPEARS that Charley had a 3 MB drop per mile ...

SF

[Derek Ortt]

I can do an approximate calculation if I can get the following data

what is the radius of curvature?

Once I get that, I can back the answer out of the gradient wind equation very easily after drinking for several hours

[tallywx]

According to my Charley radar archives, at 4:02 p.m. EDT, the very center of Charley's eye was exactly 17.8 miles away from Mark Sudduth's I-75 exit location. The closest part of the inner side of the inner eyewall (where the eyewall convection stopped and clear eye conditions began) was 14.6 miles from his location.

So 1000.14 MB - 943.28 MB/ 17.8 miles = 3.19 MB drop per mile (assuming a constant drop per mileage!). Derek, your equation can probably more accurately depict that the drop off is ever-increasing between his 4:02 location and the eye.

Let's assume that the outer edge of the eye was at 952 MB (as measured by that team in Port Charlotte). Then, we get 1000.14-952 MB/ 14.6 miles, or 3.30 MB/mile. Interesting.