As of 5:00 PM Wednesday AST, the National Hurricane Center began to issue advisories on Subtropical Storm Rebekah, 1195 kilometers east of the Azores Islands.
At 500 PM AST, the center of Subtropical Storm Rebekah was located near latitude 38.3 North, longitude 40.7 West. Rebekah is moving toward the east near 20 KM/H and is forecast to turn toward the east-northeast tonight. A turn back toward the east and east-southeast is anticipated on Thursday.
Maximum sustained winds are near 75 KM/H with higher gusts. Little change in strength is anticipated for the next day or so. Gradual weakening is anticipated thereafter, and Rebekah is forecast to become a post-tropical cyclone on Friday.
Winds of 40 MPH extend outward up to 150 kilometers from the center. The estimated minimum central pressure is 987 millibars.
Watches & Warnings
Interests in the Azores should monitor the progress of Rebekah.
There are no coastal watches or warnings in effect.
Hazards Affecting Land
Rebekah is forecast to be a post-tropical cyclone when it moves near the Azores in a day or so. Please see products issued by the Portuguese Institute for the Sea and Atmosphere (IPMA) for hazard information in the Azores related to Rebekah.
This system is of no threat to the Windward Islands, including Trinidad and Tobago.
Subtropical Storm Rebekah Discussion
Cloudiness and showers associated with a small low-pressure system embedded within a larger non-tropical low over the north-central Atlantic have become better organized during the day. The cyclone has a broken convective band that wraps about halfway around its eastern semicircle, with a small area of central convection near its center. The cloud tops within the convection are not particularly cold and the system is co-located with a large upper-level low, so it is initially designated as a subtropical cyclone. The intensity is assessed as 40 kt based primarily on earlier ASCAT data. It is worth mentioning that the system also has some characteristics of a tropical cyclone since the radius of maximum winds is not very large and the system has some moderate central convection.
Much like Pablo just a few days ago, Rebekah is currently rotating around a larger non-tropical low-pressure system. The initial motion estimate is 080/11 kt, but an east-northeastward motion is expected later tonight. The track model spread is larger than normal and confidence in the track forecast is low, though most of the models generally show Rebekah turning back toward the east by early Friday, followed by a turn toward the east-southeast until it dissipates later this week. On the forecast track, the center of Rebekah is forecast to approach the western-most Azores early Friday as a post-tropical/extratropical cyclone.
The intensity guidance unanimously forecasts that Rebekah will change little in strength during the next 24 h, though given the small size of the cyclone, some short-term fluctuations are possible tonight. Most of the dynamical models then forecast that Rebekah’s convection will decrease substantially by early Friday, likely due to a combination of colder SSTs and unfavorable upper-level winds. The cyclone is therefore forecast to become post-tropical around that time, and gradual weakening is expected. Rebekah will likely dissipate by the weekend, if not sooner.
Since Rebekah is not currently forecast to be a tropical or subtropical cyclone when it nears the Azores, hazard information can be found in regular products issued by the Portuguese Institute for the Sea and Atmosphere (IPMA) for those islands.
The larger low-pressure system in which Rebekah is embedded is responsible for our ongoing swell event.
Forecast Discussion by Forecaster Zelinsky from the NHC.