2100 UTC 12/4/2003 TROPICAL STORM ODETTE FORECAST DISCUSSION #1

This is an independent product and not from the National Hurricane Center

Despite it being after the end of the hurricane seaosn, odette is a very healthy tropical storm. The motion is to the NNE and this is the forecast track indicated by the models. Models are not of much use yet as they do not initialize the cyclone well. However, those that did somewhat initialize a vortex, bring Odette toward Haiti. This is likely with the approaching trough; therefore, this forecast does likewise. It should be noted that this track is to the right of the guidance as it brings the cyclone inland in eastern Haiti. Near the end of the period, this system should begin to merge with the larger extra-tropical low.

Initial intensity is being set at 40KT. Models are peaking this near 50KT, though I suspect that Odette is stronger than 40KT at the time. recon did not investigate this afternoon as their flight had to return to base. Visible imagery indicates a very well defined center. In addition, upper winds are somewhat favorable for further development. Therefore, this forecast will bring the system to hurricane intensity before impacting Haiti, followed by significant weakening over the mountains, with no change over the Atlantic until merger as conditions should be unfavorable by then

Initial: 14.0N 75.6W 40KT
12 Hour: 15.5N 74.1W 50KT
24 Hour: 17.0N 73.0W 60KT
36 Hour: 19.0N 72.0W 60KT (inland)
48 Hour: 21.0N 70.5W 35KT (over water)
72 Hour: 26.0N 67.0W 35KT
USE WITH EXTREME CAUTION AS FOLLOWING IS SUBJECT TO LARGE ERROR
96 Hour: Merged with larger Low

Next Discussion: 0900 UTC

Forecasters: Cangialosi/Ortt

2100 UTC 12/5/2003 TROPICAL STORM ODETTE FORECAST DISCUSSION #2

This is an independent product and not from the National Hurricane Center

Despite going to the right of all of the guidance in the last forecast, the track is still more than 100NM to the right of the forecast. Odette has been moving to the east throughout the day, with only a very slight northward component. Water vapor imagery indicates a zonal flow to the north of the system, with the digging trough lagging back over the central USA. This should allow for the zonal pattern to persist over the Caribbean for about 12 to 24 more hours, allowing for the system to move mainly to the east during this time, before starting its anticipated NE turn. Guidance is not being considered for this forecast as it insists upon an unreasonable immediate NNE track, which is not, and has not been occurring. This shifts the landfall threat more toward eastern Hispaniola and Puerto Rico, rather than the Haiti area. It is important not to focus on the precise center, which is forecast to be between the two islands, as any deviation will bring the center inland and the effects extend well away from the center.

Initial intensity is being set at 50KT, based upon satellite estimates and the recon data from earlier this afternoon. The recon data from this afternoon indicated that the pressure was initially 993mb near 12Z, then rose to 997 a couple of hours later, followed by a fall back to 995mb at 17Z. Dvorak numbers are as high as 3.5/3.5. I stayed below the 3.5/3.5 value of 55KT since recon only found maximum flight level winds to be 56KT, which equates to roughly 45KT at the surface. Guidance, which is extremely unreliable as it is somewhat track dependent, does indicate some further intensification. The current state of the storm with limited banding should preclude Odette from reaching hurricane intensity; however, it is not entirely unreasonable to envision this briefly reaching minimal hurricane strength. This forecast will peak the system at 60KT and hold that intensity until landfall, followed by a quick extra-tropical transition once it moves into the Atlantic.

Initial: 14.5N 73.3W 50KT
12 Hour: 14.9N 71.8W 55KT
24 Hour: 15.4N 70.3W 60KT
36 Hour: 16.5N 69.0W 60KT
48 Hour: 18.0N 67.8W 60KT
72 Hour: 23.0N 65.0W 40KT
USE WITH EXTREME CAUTION AS FOLLOWING IS SUBJECT TO LARGE ERROR
96 Hour: Extra-Tropical

Next Discussion: 0300 UTC

Forecaster: Ortt

0300 UTC 12/6/2003 TROPICAL STORM ODETTE FORECAST DISCUSSION #3

This is an independent product and not from the National Hurricane Center

Recon obs show that Odette is slightly left of the previous track. Models are moving more to the right. The reasoning is virtually unchanged, except for a leftward adjustment at a faster rate of speed due to the initial motion.

Initial intensity is lowered to 45KT, and this may be generous, despite the improved satellite appearance. Will now only go with slight intensification overnight now, followed by a leveling off at landfall.

Initial: 15.3N 72.6W 45KT
12 Hour: 16.3N 71.0W 50KT
24 Hour: 18.0N 69.5W 50KT
36 Hour: 20.0N 68.0W 30KT
48 Hour: 23.0N 67.0W 35KT
72 Hour: Extra-Tropical

Next Discussion: 1500 UTC

Forecaster: Ortt

1500 UTC 12/6/2003 TROPICAL STORM DOETTE FORECAST DISCUSSION #4

This is an independent product and not from the National Hurricane Center

Despite the health satellite appearance form earlier, recon has not found anything impressive, with maximum flight level winds of only 43KT. This is now way supports the 55KT used at 1100 UTC. Therefore, the winds are going to be readjusted to 45KT. Satellite imagery indicates that shear is approaching. However, there is likely to be more time over the water than previously thought since the storm is moving slower. It appears form the recon reports that the mid-level center is moving faster than the surface center, a true sign of wind shear. This is likely to delay landfall until this afternoon. However, the current track is likely to continue, bringing the storm inland in western Dominican Republic, where rapid dissipation should occur over the mountains.

Initial: 16.9N 72.1W 45KT
12 Hour: 18.5N 71.5W 25KT (inland and dissipating)
24 Hour: Dissipated

Next Discussion: 0300 UTC

Forecaster: Ortt

0300 UTC 12/7/2003 TROPICAL STORM ODETTE FORECAST DISCUSSION #5

This is an independent product and not from the National Hurricane Center

Odette is moving over Hispaniola and is expected to continue to move to the NNE and dissipate over the high mountains. There is a small chance that the cyclone may survive the track across Hispaniola; however, a land falling 45KT storm does not often survive a 12-24 hour trek across mountains that are in excess of 10,000 feet in elevation. For this reason, there are no forecast points given as the 12 hour forecast point is for the system to have already dissipated, or have weakened to a remnant low.

Forecaster: Ortt

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