Disturbance 30 Track Chart, Advisory #4

Current Location: 23N, 77.2W
Geographic Reference: 295 miles ESE of Key West, FL
Movement: West-northwest at 15 mph
Max Winds: 30 mph gusting to 35 mph
Current Hurricane Severity Index: 0 out of a possible 50 points (0 size, 0 intensity)
Max Predicted Hurricane Severity Index: 2 out of a possible 50 points (1 size, 1 intensity)
Current Radius of Tropical Storm-Force Winds: 0 miles
Max Predicted Radius of Tropical Storm-Force Winds: 50 miles
Organizational Trend: Steady
Forecast Confidence: Average

Chance of Development: 75 percent

Key Points
1. The disturbance is predicted to make landfall in southeast Louisiana as a weak tropical storm Tuesday night.
2. Regardless of tropical development, main impact will be heavy rain along the central Gulf Coast.

Our Forecast
Disturbance 30 is moving through the central Bahamas this morning. Buoys around the disturbance do not indicate any wind above 20 mph this morning. Our forecast takes the disturbance through the Florida Straits and into the southeast Gulf of Mexico late tonight. No significant wind is expected across the western Bahamas and southern Florida as it passes, but the disturbance will likely produce areas of heavy rain across the western Bahamas and southern Florida Peninsula as it passes.

Sometime during the day on Tuesday, as the disturbance is about 100 miles off the southeast Louisiana coast, we think that it will develop a closed low-level circulation with a small area of tropical storm-force winds mainly north and east of the center. The tropical storm will move ashore into southeast Louisiana by sunset on Tuesday as a tropical storm with winds of 40 mph to 45 mph. Chances of this system becoming a strong tropical storm or a hurricane are low at this time. Once inland, the storm will quickly weaken to a remnant low pressure area.

Though the system may produce wind gusts of 50 mph to 60 mph in squalls offshore on Tuesday, we do not expect any tropical storm-force sustained wind across southeast Louisiana. Wind gusts inland could reach 40 mph to 45 mph in squalls near the center on Tuesday night, but the primary impact inland will be the potential for heavy rainfall.

Expected Impacts on Land
Southern Mississippi Through Southeast Louisiana: Locally heavy rainfall could result in street flooding that leads to travel delays Tuesday afternoon through Wednesday.

Expected Impacts Offshore
Increased squalls will likely move into the southeastern Gulf of Mexico on Monday. By very early Tuesday morning, the squalls should move into the lease areas off of southeast Louisiana. Gusts could reach up to 60 mph within any squalls.

Our next advisory will be issued by 3 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 9AM CDT Sun Sep 02 23.00N 77.20W 30 mph 35 mph Tropical Disturbance 0 0 0
12 9PM CDT Sun Sep 02 24.10N 79.70W 30 mph 35 mph Tropical Disturbance 0 0 0
24 9AM CDT Mon Sep 03 25.00N 82.50W 30 mph 35 mph Tropical Disturbance 0 0 0
36 9PM CDT Mon Sep 03 26.20N 85.30W 35 mph 45 mph Tropical Disturbance 0 1 1
48 9AM CDT Tue Sep 04 27.40N 87.80W 40 mph 50 mph Tropical Storm 1 1 2
60 9PM CDT Tue Sep 04 28.90N 89.50W 40 mph 50 mph Tropical Storm 1 1 2
72 9AM CDT Wed Sep 05 30.50N 91.30W 35 mph 45 mph Tropical Depression 0 1 1
84 9PM CDT Wed Sep 05 31.70N 92.10W 30 mph 35 mph Remnant Low 0 0 0
96 9AM CDT Thu Sep 06 32.70N 92.10W 30 mph 35 mph Remnant Low 0 0 0

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.