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#1097281 (Received by flhurricane at: 4:59 AM 29.Jun.2022) TCDAT2 Potential Tropical Cyclone Two Discussion Number 7 NWS National Hurricane Center Miami FL AL022022 500 AM AST Wed Jun 29 2022 If I just took a casual look at conventional satellite data, I would think the system was already a tropical storm. There is a big ball of convection near the center, along with banding features forming in most of the quadrants of the system. Microwave data, however, does not show much low-level structure, with only broad curvature and no obvious indications of a well-defined center. Thus, the system remains a disturbance, and the initial wind speed remains 35 kt based on Dvorak estimates from TAFB. One reason that the system has been unable to close off a circulation so far is the very rapid speed, now estimated at 26 kt (or even faster in the short-term). All of the guidance continue to insist the system will slow down over the next few days due to less low-level ridging over the western part of the Atlantic basin. The low could even lose latitude over the southwestern Caribbean due to the orientation of the mid-level ridge, which more models are showing. The new forecast is faster than the previous one, ahead of the model consensus, placing more weight on the ECMWF than the GFS, the latter of which has been much too slow with this system. The disturbance will probably be struggling with, or recovering from, land interaction over the next day or so. So little intensification is shown during that time. Thereafter, the environment would seem to be conducive for significant strengthening, but it is unknown what kind of structure the system will have to potentially take advantage of the conducive conditions. Additionally, with the faster forward speed, it should spend less time over water for strengthening. Thus, the intensity forecast is reduced somewhat from the previous one, but generally remains above the model consensus. Interestingly, almost all of the models indicate that the system will survive passage across Central America and intensify in the eastern Pacific. This is now indicated in the official forecast, and could be conservative at long range. KEY MESSAGES: 1. Heavy rainfall is expected to continue across the Windward Islands and spread into parts of northern Venezuela through tonight. Localized flash flooding will be possible. 2. Winds to tropical-storm-force are expected over Islas Margarita for a few more hours, and over the ABC Islands by this afternoon. Tropical storm conditions are expected along the northwestern coast of Venezuela and northeastern Colombia tonight and early Thursday. 3. There is a greater-than-normal uncertainty in the system`s forecast intensity once it reaches the southwestern Caribbean Sea late Thursday and Friday, which will depend on how much it interacts with land from tonight through Thursday. FORECAST POSITIONS AND MAX WINDS INIT 29/0900Z 11.3N 65.4W 35 KT 40 MPH...POTENTIAL TROP CYCLONE 12H 29/1800Z 11.7N 68.4W 40 KT 45 MPH...TROPICAL CYCLONE 24H 30/0600Z 12.2N 72.2W 40 KT 45 MPH 36H 30/1800Z 12.2N 75.7W 40 KT 45 MPH 48H 01/0600Z 12.0N 79.5W 50 KT 60 MPH 60H 01/1800Z 11.8N 82.5W 60 KT 70 MPH 72H 02/0600Z 11.8N 85.8W 40 KT 45 MPH...INLAND 96H 03/0600Z 12.3N 91.3W 35 KT 40 MPH 120H 04/0600Z 13.5N 97.0W 45 KT 50 MPH $$ Forecaster Blake |