0300 UTC 9/21/2003 HURRICANE MARTY FORECAST DISCUSSION #1

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

Guidance indicates a landfall on the west coast of the Baja Peninsula. This is response to a digging trough as evidenced by water vapor imagery. Therefore, a slow but gradually accelerating track is expected over the next couple of days to the NNW then north, taking the system inland in 36 to 48 hours. This track is right of the guidance.

Initial intensity is being set to 65KT based upon three independent Dvorak estimates. I am not certain that this is a hurricane based upon the satellite signature; however, most of the evidence suggests otherwise; thus, that is what is being assumed to be the truth at the present time. SHIPS and GFDL indicate significant intensification before landfall. I will go below GFDL, which indicates 109KT at landfall due to the less than stellar appearance, but will go with a category 2 landfall.

Initial: 18.8N 108.8W 65KT
12 Hour: 20.2N 109.6W 75KT
24 Hour: 21.8N 110.4W 80KT
36 Hour: 23.5N 111.0W 85KT
48 Hour: 25.5N 111.3W 80KT
72 Hour: 30.0N 111.3W 40KT
USE WITH EXTREME CAUTION AS FOLLOWING IS SUBJECT TO LARGE ERROR
96 Hour: Remnant Low

Next Discussion: 1500 UTC

Forecaster: Ortt

1500 UTC 9/21/2003 HURRICANE MARTY FORECAST DISCUSSION #2

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

Marty has been moving little overnight, much slower than the previous forecast had been indicating. Therefore, the timing of the landfall should be delayed somewhat. Models continue to bring the system to the north and inland in about 36 to 48 hours in response to some troughing. This forecast will go with this scenario.

Marty is barely a hurricane this morning. The cloud patter is not impressive as it is elongated with most convection well south of the center. Some banding is near the center. GFDL continues to bring this to a major hurricane; however, GFDI is now backing off, only bringing the hurricane to about 90KT. SHIPS guidance is unavailable at the present time. Due to the poor signature, I am going to be more conservative and bring this to 75KT at landfall and will adjust upward once the system shows some more organization.

Initial: 19.5N 109.1W 65KT
12 Hour: 20.9N 109.8W 70KT
24 Hour: 22.5N 110.6W 75KT
36 Hour: 24.3N 111.0W 75KT(inland)
48 Hour: 26.0N 111.2W 40KT(over water)
72 Hour: 29.0N 111.2W 30KT(inland)
USE WITH EXTREME CAUTION AS FOLLOWING IS SUBJECT TO LARGE ERROR
96 Hour: Remnant Low

Next Discussion: 8 P.M.

Forecaster: Ortt

0300 UTC 9/22/2003 HURRICANE MARTY FORECAST DISCUSSION #3

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

Marty has been moving NNW due to the trough to its NW. There does not appear to be any change in the track reasoning; therefore, lets keep nearly the same track as the previous one.

Marty is showing some signs of organization this evening as convection has become concentrated near the center. This may be the start of the development that has been anticipated for the last 24 hours. With this in mind, the trend from the previous forecasts will be retained, going with slow development until landfall, which is expected in about 24 hours. Due to the small size of the storm, the system is going to be forecast to weaken considerably as it is crossing the Baja Peninsula.

Initial: 21.2N 109.9W 70KT
12 Hour: 22.9N 110.5W 75KT
24 Hour: 24.5N 110.9W 70KT (inland)
36 Hour: 26.3N 111.0W 35KT (over water)
48 Hour: 28.0N 111.0W 35KT
72 Hour: Inland and remnant low

Next Discussion: 1500 UTC

Forecaster: Ortt

2100 UTC 9/22/2003 HURRICANE MARTY FORECAST DISCUSSION #4

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

Marty has changed its heading to nearly due north and acclerated. There does not appear to be any change in the track reasoning; a trough to the northwest and ridge displaced to the ESE; therefore, lets keep nearly the same track as the previous one.

Marty has lost some of its convection today as it was interacting with the high terrain of Baja California. Steady intensity, followed by continued weakening is expected as Marty heads northward making landfall on mainland Mexico in 12 hours or so. Marty is expected to stall and dissipate over the Mexico/U.S. border in about 2 days, possibly bringing some rainfall to the desert southwest U.S.

Initial: 26.5N 110.7W 65KT
12 Hour: 28.0N 111.2W 60KT
24 Hour: 29.5N 111.6W 45KT (inland)
36 Hour: 30.3N 112.0W 35KT
48 Hour: Inland Remnant Low

Next Discussion: 0300 UTC

Forecaster: Cangialosi

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