*******Note that forecast 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.**********
...TUESDAY NOVEMBER 8 2022 6:06 AM EDT...
Even after completing the first seven days of November... the Atlantic tropics remain exceptionally and unusually active for November due to multiple areas of interest as follows:
(1) See Nicole section below for more information on the current western Atlantic subtropical storm expected to swing west into the northwestern Bahamas and Florida peninsula later this week as a potentially strengthening hurricane... with impacts also later shifting northward across the eastern US seaboard and into Atlantic Canada this weekend once Nicole transitions into a remnant frontal cyclone.
(2) See area of interest #45 section below for an update on the open Atlantic surface low pressure area still being monitored for signs of tropical cyclone formation.
(3) A tropical wave of low pressure in the open central Atlantic has potential to develop over the next five days while heading across the southern Lesser Antilles... Trinidad and Tobago... northeastern Venezuela... and the southern Caribbean Sea. See area of interest #47 section below for more information.
(4) Models have come into increasing agreement that a deep-layer ridge to spread into the Atlantic from Canada will be strong enough to cut-off the southwest portion of the current eastern Canada upper trough at a position southeast of Bermuda within the next three days. The cut-off upper trough has potential to be amplified enough to produce high upper divergence and low wind shear on its east side... an environment conducive for the development of yet another surface subtropical disturbace. An additional area of interest in the vicinity of Bermuda maybe required in future updates if these model trends continue. Any subtropical disturbance that develops here is expected to stay east of North America due to steering currents out ahead of what will be Nicole's remnant frontal cyclone.
New to this site this year... I will be sequentially numbering up areas of interest for possible Atlantic tropical development. In this scheme... will reset back to #1 at the start of next year (January 2023). The current areas of interest in this blog post are designated #45 and #47 as the other numbers were used in previous birdseye view posts. This scheme is to reduce confusion as Atlantic tropical activity increases during the peak of the hurricane season... when multiple simultaneous areas of interest begin and end which previously required shuffling around the area of interest numbers from update to update.
SUBTROPICAL STORM NICOLE... As expected... Nicole is making its westward turn in the western Atlantic around the north side of its parent upper vortex. Meanwhile the south part of the parent upper trough associated with area of interest #45 is also orbiting southwestward as a small vortex while merging with Nicole's parent upper vortex. It was also expected that Nicole's surface circulation would take advantage of water temps above 26 deg C along with the low shear environment caused by the regional deep-layer cyclonic flow (combo of Nicole's large surface circulation stacked below the upper vorticity) to build a core of showers and thunderstorms stacked over/near the surface center... and this has also happened. At this moment Nicole's increasingly active core is between the aforementioned two upper vortices... it is possible that a small area of supportive anticyclonic outflow or upper divergence between the two vortices is also helping it to generate the central showers and thunderstorms. Once this central activity's latent heat relase generates warm core cirrus outflow clouds... this will indicate Nicole has become fully tropical. It appears Nicole will become fully tropical as previously forecast.
Regarding Nicole's track... the two upper vortices mentioned in the previous paragraph along with the upper vortex currently over the Florida panhandle are expected to merge over/south of Nicole. The strong surface ridge currently approaching from Canada is also expected to mature into a warm deep-layer ridge to the north... in the warm sector of a strong frontal system currently developing over the western US. Therefore Nicole is expected to continue toward the northwestern Bahamas and into the southeastern Florida peninsula in the short-term... while steered between the north side of the upper vorticity and south side of the deep-layer ridge. Although Nicole is a touch northwest of my previous forecast track... my updated forecast track is actually nudged southwestward due to the respectable GFS-ECMWF model consensus that suggests the deep-layer ridge will be strong enough to deflect Nicole west-southwestward and then westward into the northwestern Bahamas and southeast Florida. After 48 hours... the vigorous western US frontal system and associated amplified upper trough makes its approach to bend Nicole's track northward. The model consensus is converging on the longer-range scneario I previously showed where the center of circulation accelerates north-northeastward across the eastern US from the northwestern Florida peninsula... and so my updated longer-range forecast track adopts a similar line but with faster forward speed as the models also agree the upper trough will move in a little faster toward Nicole and hence overspread Nicole with its strong eastern southerly flow sooner.
Regarding forecast intensity... Nicole gained a consolidated circulation center a little more quickly than I previously thought and is doing a good job so far in developing and then maintaining a central core of showers and thunderstorms. Also by 48 hours the cold core upper vorticity will be decaying from prolonged isolation from high-latitude cold air... potentially exposing Nicole to warm anticyclonic upper flow associated with the deep-layer ridge that will could help the storm strengthen as a fully tropical entity. Therefore my updated intensity projection is slightly increased... at this time calling for Nicole to become a category 1 hurricane while moving into the northwestern Bahamas and then move into the southeast part of the Florida peninsula while strengthening into a mid-range category 1 hurricane. This intensity projection is slightly higher than the NHC's as of this writing. Weakening is shown between 48 and 72 hours due to land interaction with the Florida peninsula. After 72 hours Nicole is expected to lose tropical characteristics but also maintain strength while transitioning into a frontal cyclone supported by the strong eastern divergence zone of the amplified upper trough to approach from the western US it will be interacting with. There is some disagreement in the models on whether or not Nicole's remnant frontal cyclone will become the dominant... or if the divergence maximum of the upper trough sets up a little further north to produce a frontal cyclone just north of Nicole such that Nicole's remnant cyclone loses identity within the dominating northern one. Either way... the wind/coastal surf impacts that will spread into the northwestern Bahamas and Florida peninsula will eventually shift northward across the entire eastern US seaboard (from Georgia to Maine) and then eventually Atlantic Canada.
Regarding impact to land areas... Nicole was born within a large subtropical surface circulation caused by the large upper divergence zone of its parent upper vortex. As such when Nicole becomes a fully tropical system and a potential category 1 hurricane... the large outer circulation will team up with it to produce stronger coastal surf over a wider area than typically seen with a category 1. Below is a regional breakdown of expected surf and other impacts:
(1) For the northeastern Caribbean Islands (Dominican Republic to Lesser Antilles)... the trailing Caribbean surface trough of low pressure pulled in by Nicole has not produced a second round of rainfall... rainfall flooding from this system is no longer anticipated.
(2) For the northwestern Bahamas... coastal surf is expected to continuously increase from now and escalate to a storm surge by Thursday once Nicole's stronger core arrives. Preparations should be underway for potentially damaging hurricane force winds and coastal storm surge... with preparations finishing on Wednesday.
(3) For Florida... coastal surf is expected to increase by tonight along all of the east coast... and escalate to a storm surge for the southeast and east-central coast (vicinity of Miami to Cape Canaveral) by Thursday and Friday once Nicole's stronger core arrives. Coastal surf will also increase on the state's western coastlines by Friday... including the Keys and Panhandle... as the western part of Nicole's large circulation overspreads the eastern Gulf of Mexico. Stronger tropical storm to hurricane force winds and gusts are expected to spread across the southern and central parts of the peninsula in the Thursday/Friday timeframe where instances of wind damage and power outages are likely. More isolated wind damage and power outages cannot be ruled out for the Florida Keys... northern third of the peninsula... and eastern Florida penhandle. Heavy rainfall with flash flooding potential will be another hazard to consider across the peninsula and eastern panhandle. I recommend preparations for the above described wind and coastal surf across the peninsula... Keys... and eastern Florida panhandle be underway now and finish on Wednesday.
(4) For the eastern half of the Carolinas and Georgia including inland areas... Nicole and its remnant frontal cyclone will be capable of producing gusty winds with isolated occurrences of damage and power outages on Saturday. Heavy rainfall with flash flooding potential will be another hazard to consider. Coastal surf and gusty winds will arrive sooner on the Atlantic coast by Wednesday and lasting through Saturday.
(5) For eastern Virginia... eastern Maryland... Delaware... eastern Pennsylvania... New Jersey... eastern New York... Connecticut... Rhode Island... Massachusetts... Vermont... New Hampshire... Maine... New Brunswick... Nova Scotia... Prince Edward Island... southeastern Quebec... and Newfoundland... there is increasing confidence that Nicole's remnant frontal cyclone (or a northern frontal cyclone that quickly forms and absorbs Nicole's remnant cyclone) will bring coastal surf and gusty winds with isolated damage potential by Sunday.
******Infohurricanes.com forecast. Visit hurricanes.gov (hurricanes dot gov) for official forecast***********
0 Hr Position (0600Z Nov 8)... 45 mph maximum sustained wind subtropical storm centered in the western Atlantic at 27.3N-71.2W
IOH 24 Hr Forecast (0600Z Nov 9)... 65 mph maximum sustained wind tropical storm centered in the western Atlantic at 27.2N-75W
IOH 48 Hr Forecast (0600Z Nov 10)... 80 mph maximum sustained wind hurricane centered over the northwestern Bahamas and just east of southeastern Florida at 26.8N-79W
IOH 72 Hr Forecast (0600Z Nov 11)... 60 mph maximum sustained wind tropical storm centered over the northwest coast of the Florida peninsula at 29N-83W
IOH 96 Hr Forecast (0600Z Nov 12)... Remnant frontal cyclone centered over the central North Carolina/South Carolina border at 35N-80W
AREA OF INTEREST #45...The surface low pressure swirl in the open central Atlantic continues to be monitored for signs of tropical cyclone formation. The current eastern Canada upper trough and associated surface frontal cyclone has freed this system from the deep-layer ridge that was previously in the region and is now accelerating the surface low and its parent upper trough east-northeastward... however these features took a little longer to knock away the deep-layer ridge and therefore the surface swirl of low pressure is located southeast of the previous forecast. The updated forecast track in the outlook below is adjsuted accordingly. Although this system is accelerating east-northeast into even cooler water temps in the low-20s of deg C... the potential for tropical cyclone formation appears open for another 12 hours due to two factors... (1) split flow upper divergence between upper southwesterlies ahead of the parent upper trough and upper northwesterlies on the northeast side of the upper ridge cell over area of interest #47 that is helping its thunderstorm activity... (2) the accelerating east-northeast motion of the surface low is allowing it to better keep up with the upper westerlies and somewhat reduce the effects of westerly wind shear such that the thunderstorm activity lopsided to the east half of the surface circulation is still nearby. The NHC has lowered peak odds of tropical cyclone formation to 30%... and in this update I have lowered them to 15%... as this system is heading into a more stable environment with upper air temps not quiet cold enough to help with instability over the low-20 deg C water (200 mb heights in the region are above 1200 dekameters). By 24 hour odds of development drop to 0% once the surface circulation is overran by the cold front of the approaching eastern Canada frontal cyclone... which should cause a loss in its tropical characteristics.
This is my planned final statement on this area of interest on this blog... unless tropical development does in fact occur within the next 12 hours.
******Infohurricanes.com outlook. Visit hurricanes.gov (hurricanes dot gov) for official outlook***********
IOH 12 Hr Outlook (1800Z Nov 8)... 15% chance of tropical cyclone formation (central Atlantic near 35N-49W)
IOH 24 Hr Outlook (0600Z Nov 9)... 0% chance of tropical cyclone formation (north Atlanitc near 39N-41W)
AREA OF INTEREST #47...A tropical wave of low pressure in the open central Atlantic produced an area of rotating thunderstorm activity near 10N-54W around 1800Z Monday which has since fizzled... however a couple of skeletal curved bands of activity remain on the east side of this rotation as of this writing. The tropical wave also remains underneath a sprawling upper ridge cell promoting low shear and upper outflow and therefore I continue to monitor it as an area of interest for tropical development. This system is expected to continue west toward Trinidad and Tobago... the southern Lesser Antilles... and across the southeastern and south-central Caribbean Sea at varying speeds over the next five days. The forward speed is expected to be slow over the next 24 hours as regional surface easterly trade winds have weakened due to the ridge weakness being generated by the current frontal cyclone heading into the Atlantic from eastern Canada. The surface trades and forward speed of this tropical wave recovers at 48 hours with the approach of a deep-layer ridge from Canada... followed by another slow down in the track at 72+ hours once encountering another area of weaker trades associated with the surface ridge weakness created by Nicole and a potential additional subtropical disturbance to form southeast of Bermuda in the days ahead (see intro section of this blog post for more info on the potential disturbance). In this update I have reduced peak odds of tropical cyclone formation to 10% due to the recent loss in the tropical wave's thunderstorm activity... and potential for some increase in westerly vertical shear in the middle of the 5-day forecast period to be caused by the upper vorticity of the increasingly likely subtropical disturbance southeast of Bermuda. In the short-term... the tropical wave will remain in an upper outflow environment conducive to redevelop thunderstorms... therefore regardless of tropical cyclone formation or not the southern Lesser Antilles... Trinidad and Tobago... and northeastern Venezuela may see heavy rainfall and gusty winds from this system by Thursday.
******Infohurricanes.com outlook. Visit hurricanes.gov (hurricanes dot gov) for official outlook***********
IOH 24 Hr Outlook (0600Z Nov 9)... 0% chance of tropical cyclone formation (east of Trinidad and Tobago near 10.5N-57W)
IOH 48 Hr Outlook (0600Z Nov 10)... 10% chance of tropical cyclone formation (between Trinidad and Tobago and southern Lesser Antilles near 11.5N-61.5W)
IOH 72 Hr Outlook (0600Z Nov 11)... 10% chance of tropical cyclone formation (southeastern Caribbean Sea near 12N-64.5W)
IOH 96 Hr Outlook (0600Z Nov 12)... 10% chance of tropical cyclone formation (just northeast of the ABC Islands near 12.5N-67.5W)
IOH 120 Hr Outlook (0600Z Nov 13)... 10% chance of tropical cyclone formation (southern Caribbean Sea near 13N-69W)
...COMPUTER MODEL SUMMARY...
Source...Florida State University Experimental Forecast Tropical Cyclone Genesis Potential Fields (http://moe.met.fsu.edu/tcgengifs/)
1200Z (Nov 7) CMC Model Run...
**For Subtropical Storm Nicole... center moves into the northwestern Bahamas at 60 hours while gradually strengthening... curves west-northwest in track and makes landfall near Cape Canaveral Florida at 72 hours... center reaches northwestern Florida peninsula at 84 hours... curves north across inland areas of the Georgia and the Carolinas through 108 hours while transitioning into a remnant frontal low... remnant low subsequently strengthens to a frontal cyclone with center over western Massachusetts at 120 hours.
**For area of interest #45... upper trough to approach from its current eastern Canada position recurves the surface low eastward with cold front driven by the upper trough absorbing the surface low while located near 35N-41W at 48 hours.
**For area of interest #47... no development shown
1200Z (Nov 7) ECMWF Model Run...
**For Subtropical Storm Nicole... center moves into the northwestern Bahamas at 54 hours while gradually strengthening... makes landfall on east Florida coast just east of Lake Okeechobee at 66 hours... center reaches the west Florida peninsula coast just north of Tampa Bay at 78 hours after which time it curves northward along/near the coast... center moves into inland southern Georgia at 96 hours and transitions into a remnant frontal low over the Carolinas through 108 hours... remnant low elongates and transitions into a cold front just offshore of the US mid-Atlantic coast by 120 hours.
**For area of interest #45... upper trough to approach from its current eastern Canada position recurves the surface low eastward with cold front driven by the upper trough absorbing the surface low while located near 36.5N-41W at 48 hours.
**For area of interest #47... no development shown
0000Z (Nov 8) GFS Model Run...
**For Subtropical Storm Nicole... center moves into the northwestern Bahamas at 42 hours while gradually strengthening... makes landfall on east Florida coast just east of Lake Okeechobee at 54 hours... center reaches the northwest Florida peninsula coast at 63 hours after which time it moves offshore into the northeast corner of the Gulf of Mexico... after turning north center makes landfall at Big Bend region of Florida panhandle at 75 hours... center moves into inland southern Georgia at 87 hours and transitions into a remnant frontal low over the Carolinas through 96 hours... remnant low subsequently strengthens to a frontal cyclone with center moving offshore from southeast Virginia at 102 hours and making landfall over Rhode Island at 108 hours... remnant frontal cyclone absorbed by more dominant frontal cyclone to the north through 117 hours.
**For area of interest #45... upper trough to approach from its current eastern Canada position recurves the surface low eastward with surface low strengthening into a tropical cyclone near 34N-49.5W at 18 hours... cyclone loses tropical characteristics while cold front of the upper trough overruns it near 36N-41W at 33 hours... remnant low loses identity on the front near 45N-24.5W at 51 hours.
**For area of interest #47... no development shown
**Southwest part of cold front that absorbs area of interest #45 and its associated upper trough becomes cut-off near 26.5N-60.5W by 78 hours... the cut-off portion of the upper trough evolves into small vortex with tail end of front evolving into a subtropical low that is swung northwest by the upper vortex to a position just east of Bermuda through 120 hours.
0000Z (Nov 8) NAVGEM Model Run...
**For Subtropical Storm Nicole... center passes just north of the northwestern Bahamas at 54 hours while gradually strengthening... curves west-northwest in track and makes landfall over northeast coast of the Florida peninsula at 66 hours... curves more north in track while moving into inland southern Georgia at 78 hours and subsequently transitions into a remnant frontal cyclone over the Appalachian Mountains of North Carolina and the Virginias through 96 hours... frontal cyclone accelerates northeast across the northeastern US and into New Brunswick through 120 hours.
**For area of interest #45... upper trough to approach from its current eastern Canada position recurves the surface low eastward with cold front driven by the upper trough absorbing the surface low while located near 36N-44W at 30 hours.
**For area of interest #47... no development shown