Frances/Ivan forecast

[obxhurricane]

Back in the Tropical cyclone forecasting chair after a week off....






--TFCTSU--

NEMAS-TFC

Tropical Storm Update

National Environmental and Meteorological Association

09:42 AM EDT Saturday, September 04, 2004



Tropical Storm Ivan



**Current position and forecast track**



Latest position and intensity:

8.8 North, 40.8 West - Highest sustained winds: 50 knots/60 mph .

12 hour forecast:

8.8 North, 40.8 West - Highest sustained winds: 55 knots/ 65 mph.

24 hour forecast:

9.0 North, 44.0 West - Highest sustained winds: 60 knots/ 70 mph .

36 hour forecast:

9.5 North, 47.5 West - Highest sustained winds: 65 knots/ 70 mph.

48 hour forecast:

10.1 North, 51.0 West - Highest sustained winds: 70 knots/ 80 mph.

72 hour forecast:

12.2 North, 56.0 West - Highest sustained winds: 80 knots/ 90 mph.



Storm Discussion:

Despite being south of 10N and some moderate shear Ivan has conintued its slow but
steady strengthening trend. Conditions along the forecast track only improve...thus
gradual strengthening is forecast to hurricane strength during the forecast period.


Our track forecast is to the south of available guidance. Ivan is being steered by a
strong sub-tropical ridge to the north which is forecast to build westward with the
cyclone. This scenario should force Ivan on a westerly heading for the first 48
hours...with a bend to the WNW forecast from 48 to 72 hours. On this track Ivan will
be a threat to the Islands in about 4 days.

OVERMAN









--TFCTSU--

NEMAS-TFC

Tropical Storm Update

National Environmental and Meteorological Association

09:16 AM EDT Saturday, September 04, 2004



Hurricane Frances



**Current position and forecast track**



Latest position and intensity:

26.7 North, 78.4 West - Highest sustained winds: 90 knots/105 mph.

12 hour forecast:

27.3 North, 79.3 West - Highest sustained winds: 90 knots/105 mph.

24 hour forecast:

27.5 North, 80.8 West - Highest sustained winds: 50 knots/ 60 mph...inland.

36 hour forecast:

28.0 North, 82.1 West - Highest sustained winds: 40 knots/ 45 mph...inland.

48 hour forecast:

29.0 North, 83.7 West - Highest sustained winds: 50 knots/ 60 mph...over water.

72 hour forecast:

31.1 North, 87.0 West - Highest sustained winds: 40 knots/45 mph...inland.



Storm Discussion:


Frances has the look of a sheared system this morning...and indeed westerly shear
continues to impinge on the cyclone. The motion continues to be slow and eratic
towrd the WNW or sometimes NW. Large scale guidance agrees on finally shoving
Frances onshore as ridging to the north of the cyclone strengthens today. The
forecast track is down the middle of available track guidance and takes hurricane
onshore in a little less than 24 hours.

Continued weaterly shear...slow motion accounting for upwelling...and interaction
with land...should all prohibit Frances from strengthening much before landfall.
Given the track forecast of Frances tracking over water in the NE Gulf of Mexico
some strengthening is indicated at 48 hours.


OVERMAN