Hurricane Isaias

Hurricane — Category 2 Isaias is packing 85-kt (100-mph) winds, moving NE at 10 kt (12 mph). Moves inland over the Alabama coast Sat as a weakening hurricane.

At 400 PM CDT (2100 UTC), the eye of Hurricane Isaias was located near latitude 24.4 North, longitude 89.3 West. Isaias is moving toward the northeast near 12 mph (19 km/h). A turn toward the north is expected on Friday. On the forecast track, Isaias is expected to pass to the north of the Yucatan Peninsula through this evening and make landfall along the U.S. northern Gulf Coast within the warning area late Friday or early Saturday. Maximum sustained winds have increased to near 100 mph (155 km/h) with higher gusts. Additional strengthening is expected through early Friday, and Isaias should remain a dangerous hurricane as it approaches the northern Gulf Coast Friday night. Hurricane-force winds extend outward up to 15 miles (30 km) from the center and tropical-storm-force winds extend outward up to 125 miles (205 km). The estimated minimum central pressure is 975 mb (28.80 inches).— National Hurricane Center · public advisory 9

This is the Atlantic · 23°N–40°N, 91°W–81°W. Isaias’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 Isaias’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.