0500 UTC 6/11/2003 TROPICAL DEPRESSION 2 FORECAST DISCUSSION #1

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

Tropical Depression 2 is currently being steered by the strong ridge to the north. The track guidance indicates a slowdown over the next few days with a deviation to the north of due west in the motion. It should be noted that the models typically have a northward bias with these types of systems; therefore, I prefer to remain on the south side of the guidance and not turn the system significantly to the north of west through the first 72 hours. Afterward, a motion to the WNW is predicted. In addition, this forecast is faster than the guidance as forward speed forecasts have also been less than stellar from developing systems in this area from the models.

The initial intensity is being set to 30KT based upon satellite estimates. The main problem with the intensity forecast is the track forecast. The intensity guidance is not al all aggressive and barely makes the system a tropical storm. However, this is based upon the official NHC track forecast. Therefore, if the models were given a southward track, the forecast would likely be more aggressive as the system would be traversing over more favorable atmospheric conditions. With the system being so close to tropical storm intensity at the time, I will go for tropical storm status in 12 hours, followed by a 45KT peak at 36 hours; then maintain the intensity through 96 hours, with a slight reduction at 120 hours as the system moves farther north, into the more unfavorable area.

Initial: 9.6N 41.6W 30KT
12 Hour: 9.8N 45.0W 35KT
24 Hour: 10.1N 48.0W 40KT
36 Hour: 10.7N 50.5W 45KT
48 Hour: 11.3N 53.0W 45KT
72 Hour: 12.5N 57.5W 45KT
Use for preliminary planning only. The following forecasts are subject to large errors
96 Hour: 14.5N 61.0W 45KT
120 Hour: 18.0N 65.0W 45KT

No graphics for this forecast.

Forecaster: Ortt

1500 UTC 6/11/2003 TROPICAL DEPRESSION 2 FORECAST DISCUSSION #2

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

Tropical Depression 2 continues to move mainly to the west, in good agreement with the previous forecast track, though very slightly slower. The system is being steered by the ridge to the north. The upper low to its west appears to belifting slightly to the north; therefore, the system may not be steered as far to the north as previously thought. The track guidance has shifted slightly to the left and the forecast does as well.

The intensity remains at 30KT. It likely would have been upgraded had the convection not died down somewhat this morning. With the upper low retreating, this may mean shear will not be as great of a factor as the models have been indicating. However, the latest SSMI pass indicates that there is a dry air intrusion occurring in the SE quadrant. This is most likely from the SAL. The guidance is split between SHIFOR and SHIPS. The former wants to intensify this while the latter weakens it. I will call for only a small increase to a tropical storm in 24 hours and leave this intensity through 96, before weakening it back to a depression due to possible shear and or land interference.

Initial: 10.1N 44.5W 30KT
12 Hour: 10.5N 47.8W 30KT
24 Hour: 11.0N 50.8W 35KT
36 Hour: 11.4N 53.8W 35KT
48 Hour: 11.9N 56.5W 35KT
72 Hour: 12.5N 61.0W 35KT
USE WITH EXTREME CAUTION. SUBJECT TO LARGE ERRORS
96 Hour: 13.5N 64.0W 35KT
120 Hour: 16.0N 67.0W 30KT

Next Discussion: 2100 UTC

Forecaster: Ortt 2100 UTC 6/11/2003 TROPICAL DEPRESSION 2 FORECAST DISCUSSION #3

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

Tropical Depression 2 continues to the west under the influence of the ridge to its north. As usual for this region, the models turned the system to the north too quickly. The track guidance has again shifted to the left of previous runs and this forecast will do the same

The initial intensity is being kept at 30KT, based upon satellite estimates. The convection is collapsing and the system barely has a closed circulation. Recent visible images may be detecting some inflow developing on the southern side, so a new convective flare up cannot be ruled out. Therefore, I will retain the system as a tropical depression through the period instead of forecasting dissipation, though the winds will be reduced to 25KT at 36 hours. If a new convective burst does not occur soon, the system would likely dissipate within the next 36 hours.

Initial: 10.1N 46.2W 30KT
12 Hour: 10.2N 49.0W 30KT
24 Hour: 10.4N 51.8W 30KT
36 Hour: 10.7N 54.3W 25KT
48 Hour: 11.0N 57.0W 25KT
72 Hour: 11.4N 59.5W 25KT
96 Hour: 11.9N 64.0W 25KT
120 Hour: 12.5N 68.0W 25KT

Next Discussion 900 UTC

Forecaster: Cangialosi/Ortt

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