Frances Advisories

[Stephanie]

The outflow on the northside of Frances seems more elongated than the south. Wouldn't this indicate and more northward direction?

[dgreen]

I heard the eye of it may go thru Gainesville and possibly Orlando as well.

[dhweather]

Too early to say, but that's certainly a possibility.

[chris_fit]

URNT12 KNHC 022307
VORTEX DATA MESSAGE
A. 02/2307Z
B. 24 DEG 12 MIN N
74 DEG 54 MIN W
C. 700 MB 2636 M
D. 70 KT
E. 145 DEG 59 NM
F. 222 DEG 89 KT
G. 138 DEG 015 NM
H. 948 MB
I. 11 C/ 3038 M
J. 18 C/ 3041 M
K. 14 C/ NA
L. OPEN SW-N
M. C20
N. 12345/7
O. .1/ 2 NM
P. AF985 2006A FRANCES OB 06
MAX FL WIND 89 KT SE QUAD 2302Z.


Winds decreased significantly

[canegrl04]

Shes dying.

[Rainband]

Good

[Hurricanehink]

Wow! An open eyewall is evident too... I really hope this isn't an eyewall replacement cycle... I'm sure Florida wouldn't mind seeing a 90 knot hurricane as opposed to a 120 knot...

[Brent]

Hurricane Frances Intermediate Advisory Number 36a

Statement as of 8:00 PM EDT on September 02, 2004

...Frances batters San Salvador island with 120 mph winds...
...Now heading toward Cat Island in the Bahamas...

a Hurricane Warning is in effect for the East Coast of Florida
from Florida City northward to Flagler Beach...including Lake
Okeechobee.

A Tropical Storm Warning and a Hurricane Watch are in effect for the
middle and upper Florida Keys from south of Florida City southward
to the Seven Mile Bridge...including Florida Bay.

A Hurricane Warning remains in effect for all of the Bahamas.

A Hurricane Warning means that hurricane conditions are expected
within the warning area within the next 24 hours. Preparations to
protect life and property should be rushed to completion.

At 8 PM EDT...0000z...the eye of Hurricane Frances was located by
reconnaissance aircraft...surface observations...satellite images
and radar...near latitude 24.3 north...longitude 75.1 west or 65
miles...105 km southeast of northern Cat Island. This is also about
355 miles...570 km...east-southeast of the lower Florida East
Coast.

Frances is moving toward the west-northwest near 9 mph...15 km/hr
...And a west-northwest to northwestward motion with some decrease
in forward speed is expected during the next 24 hours. On this
track...the core of Hurricane Frances will continue to move near
or over the central Bahamas tonight...and will move over the
northwestern Bahamas on Friday.

Maximum sustained winds are near 140 mph...220 km/hr...with higher
gusts. Frances remains a dangerous category four hurricane on the
Saffir-Simpson hurricane scale. Some fluctuations in intensity are
possible during the next 24 hours.

Hurricane force winds extend outward up to 80 miles...130 km...
from the center...and tropical storm force winds extend outward up
to 185 miles...295 km. San Salvador reported sustained winds of 120
mph when the leading edge of the eyewall passed over the island...
and sustained winds of 101 mph in the trailing edge of the eyewall.

The minimum central pressure recently reported by reconnaissance
aircraft was 948 mb...27.99 inches. San Salvador reported a
pressure of 948 mb about two hours ago when the eastern portion of
the eye passed over the island.

Storm surge flooding of 6 to 14 feet above normal tide levels...
along with large and dangerous battering waves...can be expected
near the eye of Frances on the west side of Eleuthera island...and
on the north side of Grand Bahama Island. Storm surge flooding of
4 to 6 feet above normal tide levels can be expected on the west
side of the other islands of the Bahamas. Coastal storm surge
flooding of 6 to 11 feet above normal tide levels...along with
large and dangerous battering waves...can be expected near and to
the north of where the center makes landfall in Florida.

Rainfall amounts of 5 to 10 inches...locally as high as 20 inches...
are possible in association with Frances.

Swells generated by Frances will be affecting portions of the
southeastern coast of the United States. These swells could cause
dangerous surf and rip currents.

For storm information specific to your area...please monitor
products issued by your local weather office.

Repeating the 8 PM EDT position...24.3 N... 75.1 W. Movement
toward...west-northwest near 9 mph. Maximum sustained winds...140
mph. Minimum central pressure...948 mb.

The next advisory will be issued by the National Hurricane Center
at 11 PM EDT.

Forecaster Stewart

[ColinD]

SE QUAD

[flnative]

how are the pros interpreting this?

[logybogy]

SE quad is the weakest part of the storm. Look at the Northeast quad and you'll find much greater winds.

[PurdueWx80]

That doesn't mean the winds in the entire storm are 89 kt at flight level. That is at one point in a gigantic storm. The pressure has been basically steady for several hours now, and the fluctuations are well within the error of measuring/estimating surface pressure from an airplane. A 948 pressure does not support an 80 kt hurricane.

[Hurricanehink]

I wonder why they aren't doing a public advisory every two hours. I thought they did that with storms with hurricane warnings

[kevin]

How can Stewart say that with the 89kt vortex messege???

[Brent]

120 mph sustained at San Salvador. This is at least a Cat 3.

[chris_fit]

Vortex winds were in the WEAKEST part of the storm.

[Air Force Met]

Shes dying.

Uhhh...no she's not. Once her inflow is no longer coming off the DR...and once she gets over the higher heat content areas to her NW...her eyewall will get its act together and she will be bacl into the 930's or even 920s with her pressure.

She's also just moved over an area with low TCHP...heat content. Once she gets past 75 ot 76 west...that wil change dramitically.

[charleston_hugo_veteran]

Today's Discussion
POSTED: September 2, 2004 7:07 p.m.


Category 4 Hurricane Frances, as of 5 p.m. EDT, is centered at 24.1 north and 74.4 west, 375 miles east-southeast of lower Florida east coast. Frances is moving toward the west-northwest at 10 mph. Maximum sustained winds are 140 mph. San salvador in the Bahamas reported a wind gust 114 mph. The central pressure is 947 millibars (27.93 inches). A hurricane warning is in effect for all of the Bahamas. A hurricane warning is now in effect for the Florida east coast, from Florida City northward to Flagler Beach, including Lake Okeechobee. A tropical storm warning and a hurricane watch are in effect for the middle and upper Florida Keys, from south of Florida City, to the Seven Mile Bridge, including Florida Bay.

Frances is moving west-northwest at about 10 mph. The thing to watch is movement and speed. If Frances starts to slow down more then this will buy more time for Florida and could allow the system to turn more northwesterly. The system will be affected by eye wall replacement in a way that as the inner eye wall dies the pressure will rise. Then the outer eye wall will contract causing the pressure to fall and the wind to increase. This process takes 6 to 10 hours. So, don't be surprised to see fluctuations of pressure and wind speed. An upper-level ridge of high pressure to the north of Frances is the key for movement. Meanwhile, an upper-level trough now coming into the northern Rockies will interact with the upper ridge later in the weekend and early next week. Each model has its own take on the interaction of this eastward moving upper-level trough and the ridge. Basically, a relatively strong high to the north of Frances will keep it on a course for Florida, and all the data and observations we have looked at this morning and midday say that is the most likely scenario. However, a weaker ridge, or high to the north will allow Frances to slow down and take on more of a northwesterly turn, meaning Georgia and the Carolinas are in line for a landfalling hurricane. As for the timing of landfall, keeping the storm's current forward speed and movement, Frances will make landfall between Melbourne and West Palm Beach Saturday. A slowdown, and subsequent turn to the northwest means a much later arrival, much farther up the east coast.

Elsewhere the Atlantic Basin, we have a 1012 millibar low near 19 north, 40 west; fairly strong convection, or thunderstorms have been associated with this wave, and there is room for this to strengthen over the next couple of days. A strong tropical wave is moving across the Cape Verde Islands. A tropical wave is along 58 west, south of 24 north.

[Brent]

They only do advisories every 2 hours once the eye can be tracked by radar.

[Hurricanehink]

The 89 knot vortex message was recorded after a 115 knot vortex message. I guess where they measured it it wasn't as strong. Maybe the 115 was in the NE quadrant.