*******Note that forecasts and outlooks in this post are NOT the official forecast from the National Hurricane Center (NHC). They are my own detailed views on the Atlantic tropics based on current observations and latest computer model runs. As such do not make decisions based on my posts...consult news media...watches and warnings from your local weather office...and any evacuation orders issued by local governments to make the most informed and best decisions. Visit the NHC website hurricanes.gov (hurricanes dot gov) for the latest watches/warnings and official forecasts on active tropical cyclones.*********
...SATURDAY NOVEMBER 2 2024 9:30 PM EDT...
The following is a special update on the surface cyclone which has moved into the Azores while becoming Subtropical Storm Patty. Refer to full update #111 (https://www.infohurricanes.com/post/my-2024-atlantic-hurricane-season-birdseye-view-post-111) for information on activity elsewhere in the Atlantic tropics.
SUBTROPICAL STORM PATTY… Visible satellite image of Subtropical Storm Patty as of 1650Z while it moves into the Azores island chain. Left arrow marks the western group of islands (Corvo and Flores)… middle arrow marks the central group of islands (Faial… Pico… Sao Jorge… Graciosa… Terceira)… and the right arrows mark the easternmost islands (Sao Miguel to the north and Santa Maria to the south):
The surface cyclone that has been moving toward the Azores from the central Atlantic… tagged as area of interest #45 in previous post #111…. was upgraded by the NHC to Subtropical Storm Patty early today due to persistent showers and thunderstorms at the core area of the cyclone. During the 5 AM EDT upgrade Patty took a southeast dive that allowed it core area to pass just south of Corvo and Flores while cyclonically orbiting a field of low surface pressures to the northeast induced by the northeast divergence zone of the overhead upper vortex. At its upgrade Patty was estimated to have 50 mph maximum sustained winds… however at 11 AM EDT Patty’s strength was increased to 65 mph maximum sustained winds based on a satellite scan of winds. The data showed the highest winds are primarily south of the center probably due to the brisk east track enhancing the winds south of center and slowing the winds north of center… which allowed Corvo and Flores to dodge the storm force wind field. The track forecast going forward is for Patty to increasingly bend north in its eastward trajectory while encountering the southerly flow between the British Isles deep-layer ridge and frontal system that recently moved into the North Atlantic from eastern Canada. Regarding intensity… the core showers and thunderstorms have not released enough latent to generate a layer of warm core outflow above the surface and below the overhead upper vortex to support additional strengthening… and likewise Patty has not been upgraded to fully tropical status. And combined with a lack of divergence beneath the core of the overhead upper vortex… I agree with Patty weakening going forward. In the upper-levels… the overhead upper vortex will also similarly arc north in the flow between the British Isles ridge and approaching North Atlantic frontal system… and open into an NW/SE tilted upper trough while slowly merging with the upper trough of the incoming frontal system. Between 24 and 48 hours my updated track forecast is north enough to allow Patty to align with the divergence zone of the tilted upper trough… thus I slow the weakening rate during the time. However I also show Patty being a non-tropical remnant low by 48 hours as the track places Patty into even cooler waters well below 20 deg C.
All of the Azores have and will continue to see coastal surf from Patty through the remainder of tonight. The central Azores are now seeing heavy rainfall from Patty’s core… and once the center moves through the central islands are at risk of seeing gusty storm force winds within the next couple of hours especially as the track bends increasingly north which will help the strongest winds south of center overspread the islands. The eastern islands will likely miss the small core of heavy rain on the current forecast track… but will be well within the storm force winds south of center at some point during the early morning hours. Interests in the central and eastern Azores should be prepared to shelter indoors in an interior room when strong winds arrive.
******Infohurricanes.com forecast. Visit hurricanes.gov (hurricanes dot gov) for official forecast***********
0 Hr Position (1800Z Nov 2)... 65 mph maximum sustained wind subtropical storm centered just west-southwest of the central Azores at 38N-30.1W
IOH 24 Hr Forecast (1800Z Nov 3)... 50 mph maximum sustained wind subtropical storm centered northeast of the eastern Azores at 39N-22.5W
IOH 48 Hr Forecast (1800Z Nov 4)... 45 mph maximum sustained wind remnant low centered in the northeast Atlantic at 43N-15W
*****National Hurricane Center (hurricanes.gov) official forecast as of 5 PM EDT*************************
3-Day Position (1800Z Nov 5)… 30 mph maximum sustained wind dissipating remnant low centered just offshore of the Spain/Portugal border at 41.7N-9.8W
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