• Bryan Norcross

Peter, Rose, and a new system forming in the Atlantic

Tropical Storm Peter is heading for the waters north of Puerto Rico, which would normally concern us in Florida. That’s the alley that some epic hurricanes that have hit the state have taken. We have confidence, however, that Peter will turn north before it even reaches the Bahamas.



You can clearly see the naked low-level circulation on the satellite due to hostile upper-level winds pushing the taller thunderstorms off to the east. And those upper winds are only forecast to get stronger over the next couple of days as the system slows down north of the Caribbean islands. About Wednesday, the steering winds are forecast to switch around and turn Peter to the north.


Peter should stay far enough north of the islands to have a minimal effect. Although some enhanced rainfall is likely from moisture associated with the upper-level low just ahead of Peter – the system that’s supplying the hostile upper winds. Then tomorrow and Wednesday, Peter itself will draw extra moisture over the mountainous islands.


Peter is forecast to fade away in a few days as it becomes completely discombobulated by the strong upper winds.



Between Peter and Africa is Tropical Storm Rose. This system is also under hostile upper winds, so it hasn’t been able to strengthen significantly. After a little strengthening in the short term, a couple days from now, the environment is expected to become even less supportive, so weakening is forecast as it tracks harmlessly to the north and weakens in the dry, dusty air.



We continue to tick through names at a stunning rate. The record book shows only two years, 2005 and 2020, when we reached the “R” name by this date. And it’s very likely we will add Sam to the list this week.


But first, we have to talk about ex-Odette. The storm that was Tropical Storm Odette a few days ago is slowly maneuvering just off the coast of Newfoundland as a winter-type low-pressure system. The weak steering currents are forecast to deflect ex-Odette south toward somewhat warmer water. There is a chance that it could regain some tropical characteristics, which will be amusing meteorologically. But the main question is, how might it affect likely-Sam down the road?


There is no Sam yet, of course. But the disturbance that moved off Africa yesterday is likely to develop into our next storm to watch. Assuming the forecasts are right, the name will be Sam.


This one is farther south than Rose, so it will avoid the mass of Saharan air that remains over the east Atlantic. But late in the week, with Rose moving north and ex-Odette moving south, the low pressure of those systems will develop a big gap in the high pressure that normally drives African systems to the west. To what degree will likely-Sam turn north into that gap, or will it stay far enough south to avoid the open door?


It will be our project this week to watch this scenario develop involving ex-Odette, Rose, and likely-Sam. The computer forecast models offer differing predictions of how this dance is going to play out. Once likely-Sam develops an organized circulation, hopefully they will settle down and be more consistent.


A huge dip in the jet stream is forecast over the eastern part of the U.S. this week. This will bring most of the East some cool fall weather. For South Florida, however, it means rain. The associated cold front will lodge to the north creating a corridor of heavy moisture over the southern peninsula.


This jet stream dip will also deflect likely-Sam and anything else away from the U.S., if the tropical system tracks far enough north. We want to watch out for systems that track well south of the dip, however, because they can get pulled north over Florida and the Southeast. That’s the usual October scenario, and why October is a busy hurricane month in Florida.


We’ll be watching this play out for a while. Likely-Sam won’t even reach the Caribbean islands until the end of week, if it even gets there. It might well get attracted to ex-Odette and dying-Rose first and turn to the north.