Current Location: 14.7N, 45.3W
Geographic Reference: 1145 miles east of Martinique
Movement: West at 16 mph
Max Winds: 75 mph gusting to 85 mph
Current Hurricane Severity Index: 8 out of a possible 50 points (3 size, 5 intensity)
Max Predicted Hurricane Severity Index: 8 out of a possible 50 points (3 size, 5 intensity)
Current Radius of Tropical Storm-Force Winds: 45 miles
Max Predicted Radius of Tropical Storm-Force Winds: 70 miles
Organizational Trend: Slowly Strengthening
Forecast Confidence: Average
Key Points
1. Isaac is predicted to strike the central Lesser Antilles as a strong tropical storm Thursday.
2. Weakening and dissipation is expected in the Caribbean due to strong wind shear.
Our Forecast
Although Isaac appeared to develop a small eye early this morning, latest microwave imagery and visible satellite imagery both indicate that the eye is no longer present. We think that Isaac has weakened below hurricane strength. Given its rather disorganized appearance on satellite imagery, it is questionable whether Isaac will regain hurricane strength prior to reaching the eastern Caribbean on Thursday.
We have not made any significant changes in the forecast track. Once Isaac moves past the Lesser Antilles on Thursday afternoon, we expect it to slowly weaken to a remnant low as it passes well south of the Dominican Republic on Saturday. It does not appear likely that Isaac will reach the Gulf of Mexico.
Expected impacts on Land
Central Lesser Antilles: Widespread power outages are expected within about 45 miles of the center, along with moderate structural damage. Flooding and mudslides are likely to cause some damage and travel delays.
Our next advisory will be issued by 10 PM AST / 9 PM CDT.
Meteorologist: Chris Hebert
| Forecast Confidence: Average | Hurricane Severity Index | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Fcst Hour | Valid | Lat. | Lon. | Max Sustained Winds | Max Gusts | Category | Size | Intensity | Total |
| 0 | 3PM CDT Mon Sep 10 | 14.70N | 45.30W | 75 mph | 85 mph | Category 1 | 3 | 5 | 8 |
| 24 | 3PM CDT Tue Sep 11 | 14.80N | 51.10W | 70 mph | 80 mph | Tropical Storm | 2 | 4 | 6 |
| 48 | 3PM CDT Wed Sep 12 | 15.10N | 56.30W | 70 mph | 80 mph | Tropical Storm | 2 | 4 | 6 |
| 60 | 3AM CDT Thu Sep 13 | 15.50N | 59.40W | 65 mph | 75 mph | Tropical Storm | 2 | 3 | 5 |
| 72 | 3PM CDT Thu Sep 13 | 15.70N | 62.40W | 60 mph | 70 mph | Tropical Storm | 2 | 3 | 5 |
| 84 | 3AM CDT Fri Sep 14 | 15.70N | 65.60W | 45 mph | 60 mph | Tropical Storm | 1 | 2 | 3 |
| 96 | 3PM CDT Fri Sep 14 | 15.80N | 68.50W | 40 mph | 50 mph | Tropical Storm | 1 | 1 | 2 |
| 108 | 3AM CDT Sat Sep 15 | 15.90N | 71.80W | 35 mph | 45 mph | Tropical Depression | 0 | 1 | 1 |
| 120 | 3PM CDT Sat Sep 15 | 15.70N | 73.90W | 30 mph | 40 mph | Remnant Low | 0 | 0 | 0 |
| 132 | 3AM CDT Sun Sep 16 | 15.00N | 75.50W | 35 mph | 40 mph | Remnant Low | 0 | 1 | 1 |
The yellow cone represents track error from the previous five hurricane seasons. Over the past five hurricane seasons, the center of the storm tracked within the yellow cone 75% of the time. The cone does not represent the forecast uncertainty in the current advisory for this storm. In addition, hurricane-force winds, very high tides, large waves, and heavy rainfall can often extend well outside the yellow cone.
