Perceptible pressure drop since noon Nassau, Bahamas........

[dixiebreeze]

Latest 8 PM (0) Sep 14 84 (29) 73 (23) 29.94 (1014) NE 9
7 PM (23) Sep 14 84 (29) 73 (23) 29.94 (1014) NE 12
6 PM (22) Sep 14 86 (30) 73 (23) 29.94 (1014) NE 12
5 PM (21) Sep 14 86 (30) 75 (24) 29.94 (1014) ENE 14
4 PM (20) Sep 14 87 (31) 75 (24) 29.94 (1014) ENE 14
3 PM (19) No Data
2 PM (18) Sep 14 87 (31) 73 (23) 29.97 (1015) ENE 12
1 PM (17) No Data
Noon (16) Sep 14 87 (31) 73 (23) 30.00 (1016) E 12
11 AM (15) Sep 14 87 (31) 77 (25) 30.03 (1017) E 9

Probably means nothing but interesting anyway, since the pressure there has been around 30.00 for so long.

[Josephine96]

I noticed that too Dixie... Pressures have been goin down around there.. Good post

[Stormsfury]

Pressures have been locked steady at 29.94" since 4 pm. Part of that was likely diurnal in nature.

SF

[mf_dolphin]

We normally get a pressure drop here as well during the evening. It will be interesting to see if the trend continues. I aslo noticed a definite wind shift - E -> ENE -> NE hmmmmm

[rob8303]

We normally get a pressure drop here as well during the evening. It will be interesting to see if the trend continues. I aslo noticed a definite wind shift - E -> ENE -> NE hmmmmm

What does this mean? a shift to e-ene-NE? Please explain in layman's terms. Thanks in advance

[dixiebreeze]

Dolphin, could you elaborate on the "definite wind shift?" Thanks.

[mf_dolphin]

When I see a wind shift from E to NE that tells me something is changing in the environment. I'm not an expert in the tropics but I suspect that Isabel is the cause of the shift. It could also be as simple as a seabreeze seeting in. I just like to watch for changes and try to understand why it's happening

[dixiebreeze]

Thanks Dolphin.

[wxman57]

The NE wind is due to Isabel about 500 miles to the east. Northeast winds extend from the central Gulf of Mexico, across Florida and up the east coast to North Carolina. Isabel's closed circulation isn't that large, but it has made a "dent" in the high pressure area that normally dominates this region. Winds west of Isabel are from the northeast over a large area, they're from the southeast east of Isabel's center.

The pressure drop in Nassau is most likely a normal diurnal change. Typically, pressures fall during the day as the ground heats up. After sunset, the ground cools and pressures begin rising up until mid morning. I don't think Isabel's pressure field extends quite that far, but with a trof approaching the southeast coast in the next few days, and Isabel off to the east, pressures sure will be falling there.

[dixiebreeze]

Thanks wxman57, very good explanation.

[ColdFront77]

Two things:

1.) It would be nice to know the average pressure fall in the afternoon into evening pressure, so we can get an idea what the minimal fall (added to the average) indicating that a low pressure is moving toward a certain location.

- and -

2.) A northeast wind with continual pressure drop tends to indicate that a storm is at least approaching your area.

[dixiebreeze]

Pressures staying down in Nassau, Bahamas:

http://weather.noaa.gov/weather/current/MYNN.html

[Josephine96]

Dixie.. have you seen the latest satellite... take a look at how close she really is...

[dixiebreeze]

Yep John, I know.