1500 UTC 6/17/2003 TROPICAL DEPRESSION 1 FORECAST DISCUSSION #1

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

The Tropical Depression off the coast of Mexico continues to move north/northwest. Most of the models agree on the continuous N/NW track towards the dry air.While the storm may temporarily strengthen, the storm should greatly weaken once it reaches the dry atmosphere. We will continue to monitor the storm and its progression towards the dry air over the next few days.

Initial: 17.0N 103.5W 30KT
12 Hour: 17.7N 103.9W 35KT
24 Hour: 18.5N 104.4W 35KT
36 Hour: 18.9N 105.5W 30KT
48 Hour: 19.4N 106.5W 25KT
72 Hour: 19.9N 108.5W 25KT

Next Discussion 2100 UTC

Forecasters: Cangialosi/Desflots

2100 UTC 6/17/2003 TROPICAL STORM BLANCA

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

Blanca continues to move slowly with the center being located to the south of the previous position. The motion is being set as stationary for this package. Again, the global models cannot represent reality as they do not depict the system. The track guidance favors a NW motion, with a westerly turn. BAMD indicates a more northerly track, but the system should be shallow, making this guidance irrelevant. This forecast will be shifted to the south of the previous one to represent the change in the center location. This is in good agreement with the BAMM model.

The initial intensity is being set to 45KT. This is based on the SSD and NWHHC estimates. SHIPS was initialized at 35KT; therefore, it's guidance may be under representative. Blanca has only about 24 hours in order to intensify before running into cooler waters, dry air, and vertical wind shear. With the system not appearing to be vertically stacked, hurricane intensity appears unlikely. The forecast will be higher than the previous to reflect the initial intensity, though the same general trends are followed. A peak intensity of 55KT is forecast in 24 hours, followed by a weakening to 30KT at 72 hours as Blanca moves into an unfavorable environment. If Blanca remains stationary longer than anticipated, then it would have the opportunity to intensify into a hurricane.

Initial: 16.7N 103.7W 45KT
12 Hour: 17.2N 104.1W 50KT
24 Hour: 17.6N 104.7W 55KT
36 Hour: 17.9N 105.7W 55KT
48 Hour: 18.2N 106.9W 45KT
72 Hour: 18.6N 109.5W 30KT

Next Discussion: 900 UTC

Forecaster: Ortt

1500 UTC 6/18/2003 TROPICAL STORM BLANCA FORECAST DISCUSSION #3

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

Blanca remains to be fairly well organized in a similar position in the past 12 hours. The motion is being set as stationary for this package. track guidance favors a NW motion, with a westerly turn. BAMD indicates a more northerly track, but the system should be shallow, making this guidance irrelevant.

The initial intensity is being set to 45KT. This is based on the SSD and NWHHC estimates. Blanca has only about 24 hours in order to intensify before running into cooler waters, dry air, and vertical wind shear. With the system not appearing to be vertically stacked, hurricane intensity appears unlikely. A peak intensity of 55KT is forecast in 24 hours, followed by a weakening to 30KT at 72 hours as Blanca moves into an unfavorable environment. If Blanca remains stationary longer than anticipated, then it would have the opportunity to intensify into a hurricane.

Initial: 17.0N 104.1W 45KT
12 Hour: 17.2N 104.4W 50KT
24 Hour: 17.5N 104.9W 55KT
36 Hour: 17.9N 105.7W 50KT
48 Hour: 18.2N 106.9W 45KT
72 Hour: 18.6N 109.5W 30KT

Next Discussion: 2100 UTC

Forecaster: Cangialosi/Desflots

2100 UTC 6/18/2003 TROPICAL STORM BLANCA FORECAST DISCUSSION #4

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

Blanca continues to mvoe little as it is located in a weak steering environment. Track guidance continues to indicate a slow WNW motion with the building ridge to the north and the forecast does likewise, albiet faster than the previous forecast.

Initial intensity will remain at 45KT is agreement with the NWHHC and SAB estimates. Visible imagery indicates that the center is on the eastern edge of the convection, indicative of easterly shear. This, along with the dry air and cooler waters to the NW should serve to weaken the cyclone. The intensity is being held to 45KT and weakening the system to 25KT in 72 hours.

Initial: 16.6N 104.5W 45KT
12 Hour: 16.9N 105.5W 45KT
24 Hour: 17.2N 106.5W 40KT
36 Hour: 17.6N 107.6W 40KT
48 Hour: 17.9N 109.0W 30KT
72 Hour: 18.5N 112.0W 25KT (Dissipating)

Next Discussion: 1500 UTC

Forecaster: Ortt

1500 UTC 6/19/2003 TROPICAL STORM BLANCA FORECAST DISCUSSION #5

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

Blanca has begun moving very slowly to the west. The weakness to the north remains; thus, only a slow motion is expected during the forecast period. With the system expected to become shallow, the system will be carried by the low-level flow. The track guidance agrees with this scenario. This forecast is slightly to the south of the previous one.

The initial intensity remains 45KT for this package. After collapsing overnight, the deep convection has returned near the center. That being said, the center remains on the NE side of the convective envelope. This suggests continues easterly shear. This is expected to continue and the system is moving into an area of very dry air. In addition, none of the intensity guidance suggests intensification; therefore, a slow weakening is expected during the forecast period.

Initial: 16.9N 105.1W 45KT
12 Hour: 17.0N 106.0W 40KT
24 Hour: 17.2N 107.0W 40KT
36 Hour: 17.4N 108.0W 35KT
48 Hour: 17.5N 109.2W 30KT
72 Hour: 17.5N 112.0W 25KT (Dissipating)

Next Discussion: 2100 UTC

Forecaster: Ortt

2100 UTC 6/19/2003 TROPICAL STORM BLANCA FORECAST DISCUSSION #6

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

The position of Blanca is hard to determine with the collapse of the convection. Visible imagery shows multiple circulations. The center will be set in the center of the canopy for the time being. The QUIKSCAT from this morning missed the system, though it did show some curvature near 16.5N. The center for now will be slightly to the south of this position. As for the track, a slow westerly track is predicted, in agreement, though to the south of, the previous forecast due to the relocation of the center. In addition, this track is slightly faster as the shallow system should be steered by the low-level flow.

The initial intensity is being lowered to 40KT, slightly lower than the satellite estimates. The reason for this is the reduction in the convection. Continued weakening is expected due to easterly shear and dry air. The rate of weakening is a bit faster than the guidance suggests. The system is forecast to be a remnant low in 72 hours, if not sooner.

Initial: 16.4N 105.5W 40KT
12 Hour: 16.4N 106.5W 35KT
24 Hour: 16.4N 107.6W 35KT
36 Hour: 16.5N 108.9W 30KT
48 Hour: 16.5N 110.5W 25KT (Dissipating)
72 Hour: 16.5N 114.0W 15KT (Remnant Low)

Next Discussion: 1500 UTC

Forecaster: Ortt

1500 UTC 6/20/2003 TROPICAL STORM BLANCA FORECAST DISCUSSION #7

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

Blanca is moving slowly to the SW this morning. With Blanca being fairly shallow and expected to become more shallow, the BAMS model will be followed fairly closely and call for a continuation of the westward track through 72 hours.

Initial intensity is being set at 35KT based upon satellite estimates. The recent convective burst is not expected to last long due to easterly wind shear. After this burst dissipates, dissipation hould ensue. The system is forecast to be a remnant low in 48 hours, a bit faster than SHIPS is suggesting.

Initial: 15.8N 106.0W 35KT
12 Hour: 15.8N 107.3W 35KT
24 Hour: 15.8N 108.5W 30KT
36 Hour: 15.8N 109.9W 25KT (Dissipating)
48 Hour: 15.8N 111.5W 20KT (Remnant Low)
72 Hour: 15.8N 116.0W 15KT (Remnant Low)

Next Discussion: 2100 UTC

Forecaster: Ortt

2100 UTC 6/20/2003 TROPICAL DEPRESSION BLANCA FORECAST DISCUSSION #8

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

Now that Blanca is shallow, it should be steered strictly by the low-level flow. GFDL keeps the system on a westerly motion as does this forecast. This is to the south of much of the other guidance.

Initial intensity is being set to 30KT. With the mid-level center being sheared more than 150KT miles to the WNW of the surface center, weakening to a remnant low should occur within the next 24 hours.

Initial: 15.4N 106.0W 30KT
12 Hour: 15.4N 107.0W 25KT (Dissipating)
24 Hour: 15.4N 108.2W 20KT (Remnant Low)
36 Hour: 15.4N 109.5W 15KT (Remnant Low)
48 Hour: Remnant Low

Final Forecast Discussion

Forecaster: Ortt

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