Tropical Storm Fay

Tropical Storm Fay is packing 45-kt (50-mph) winds, moving W at 5 kt (6 mph). Expected to stay over open water.

At 900 PM GMT (2100 UTC), the center of Tropical Storm Fay was located near latitude 29.8 North, longitude 41.8 West. Fay is moving toward the west near 6 mph (9 km/h). A generally westward motion with some decrease in forward speed is expected over the next few days. Maximum sustained winds are near 50 mph (85 km/h) with higher gusts. Some strengthening is possible overnight before weakening likely commences by Friday afternoon. Tropical-storm-force winds extend outward up to 80 miles (130 km) from the center. The estimated minimum central pressure is 1005 mb (29.68 inches).— National Hurricane Center · public advisory 19

This is the Atlantic · 27°N–33°N, 50°W–40°W. Fay’s forecast track is the dotted spine — the labelled dots mark its position each day. Every cell is shaded by how many hours it spends inside Fay’s gale-force (≥34 kt · 39 mph) wind across the whole forecast, the damaging core counted double.

Read it two ways at once. Colour is the total — the hours of gale-force wind a place piles up. A slow storm writes its danger in duration, not in any single gust, so the longer the wind sits over a place, the deeper its colour. Opacity is confidence — solid where the official probability of that wind is high, faint where it is only a chance. So a deep, solid cell is a place the wind will work for a long time and likely will; a pale, faint one is a brief, uncertain brush at the edge of the cone.