Update: Martinique radar shows Maria’s eye coming ashore on the east coast of Dominica.
Hurricane Maria has developed explosively this afternoon as it passed north of the island of Martinique on track to the west coast of the beautiful island of Dominica. When Maria hit the deep pool of warm water that has built up in front of the islands its eyewall tightened up, the eye became clear and the cloud tops rose up so high that they cooled to -74º Celsius or -101º F. This combination of cold cloud tops and warm pinhole eye has an objectively estimated wind speed of 140 knots or 160mph if the hurricane has had sufficient time to spin up. At 5pm the National Hurricane Center determined that Maria’s wind speed was 115 knots or 130 mph conservatively, a minimal category 4 hurricane. Expect the speed to be raised considerably when new airplane radar wind speeds are determined later this evening.
The largest towns on Dominica are on the leeward side so most of the people and infrastructure of Dominica will escape the worst winds and most of the storm surge. The island is mountainous so the towns on the Caribbean may get some protection. However, downslope winds can be extremely destructive coming through gaps in the mountains. The quaint east side shown in the picture above, facing the Atlantic, will be devastated.
Based on its structure on radar and satellite I suspect that Maria has already spun up to category 5. Objectively estimated wind speeds were consistently lower than airplane determined wind speeds for Hurricane Irma. Maria now has higher raw objective values than Irma did. The only good news is that the area of strong winds is very small. The radar image shows that the strongest winds are in the yellow orange area north of the eye. The worst damage will be along a swath 5 to 10 miles wide.
Both Irma and Maria underwent explosive development when they reached the deep pool of warm water on the north side of the Caribbean sea and on the north and east Atlantic sides of the islands of the Caribbean. Light wind shear and favorable September atmospheric conditions, have led to the formation of multiple tropical storms over the Atlantic this year. The extreme amount of heat stored in the ocean, which can be linked to the effects of greenhouse gases as described in his huge recent paper about stronger Atlantic storms, fueled the explosive development of both Hurricane Harvey and Hurricane Irma. Now it is fueling the explosive development of Hurricane Maria.
Unfortunately, this quaint little cafe in Dominica is right in Maria’s path.
The latest report from the hurricane hunter plane shows Maria has 140 knot 160mph category 5 winds. This report is subject to NHC adjustment but it is consistent with radar and satellite data.
People in Puerto Rico doen’t have much time to get ready because this monster will be bearing down on the south shore early Wednesday morning.