MY 2025 ATLANTIC HURRICANE SEASON BIRDSEYE VIEW POST #57

*******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.*********

...WEDNESDAY AUGUST 13 2025 3:45 AM EDT...

Noting it has been a little over 48 hours since my previous update late Sunday/ early Monday due to recent activities in my personal life. I have been gradually putting this update together throughout Tuesday through now... with the above birdseye view satellite image... surface chart... and upper air chart put together earlier on Tuesday. The text and forecasts below were then completed by 3:45 AM EDT today (Wednesday) based on satellite observations through 0330Z.

Atlantic tropical activity remains high with the formation of a new tropical storm in the eastern tropical Atlantic occurring alongside four other concurrent areas of interest within the last 48 hours:

(1) See Tropical Storm Erin section below for information on the new tropical storm... the tropical storm is expected to strengthen into the first hurricane of the 2025 Atlantic season and bring surf to the shores of the northeastern Caribbean Islands and Bermuda in the days ahead.

(2) See area of interest #14 section below for a final update on the tropical low that was in the open central Atlantic

(2) See area of interest #15 section below for a final update on the northwestern Atlantic deep-layer low (surface low stacked below an upper vortex) that was being monitored for signs of tropical development.

(3) See area of interest #17 section below for a final update on the eastern Gulf of America disturbance which made landfall in southeastern Louisiana late Tuesday.

(4) Sea area of interest #18 section below for more information on a disturbance that has rapidly materialized in the western Caribbean. The disturbance is not expected to develop today while crossing the Yucatan peninsula... however it could develop while crossing the Bay of Campeche and southwestern Gulf of America on Thursday on its way to northeastern Mexico.

Elsewhere in the Atlantic basin... the large eastern Atlantic tropical wave of low pressure that Tropical Storm Erin formed within lingers to the southeast of Erin... and is likely to merge with the tropical wave that recently emerged from the west coast of Africa. Additional waves are forecast to emerge from the west coast of Africa on day 2 and day 5... and there is potential for the waves to merge into a lengthy surface trough spanning the central and eastern tropical Atlantic. Will watch for the development of well-defined rotations within the possible surface trough in the days ahead and declare new areas of interest in future updates as needed.

TROPICAL STORM ERIN... Left... satellite image of Tropical Storm Erin reaching peak organization shortly after its formation Monday evening and before succumbing to dry Saharan air on Tuesday. Right... recent satellite image of Tropical Storm Erin beginning to re-develop thunderstorms tonight:

The westward-moving tropical low that was producing bursting thunderstorms over the northern Republic of Cabo Verde Islands on Sunday proceeded to be upgraded by the National Hurricane Center to Tropical Storm Erin with 45 mph maximum sustained winds as of 11 AM EDT Monday. For much of Tuesday the tropical storm appeared to ingest the thick dry Saharan air just to the east which caused a loss of thunderstorms in the circulation. However as of tonight (late Tuesday through early Wednesday) it appears Erin is recovering while moving into lower concentrations of dry Saharan air as seen by an increase in thunderstorms just southwest of center. Since formation storm motion has been rapid to the west in the strong flow between the north side of the large-scale tropical wave it formed within and south side of the Atlantic surface ridge... and in recent hours there is a south deflection in the west track while Erin is affected by the cyclonic flow in the northwest side of the large-scale tropical wave. Going forward Erin is expected to gradually slow its forward speed and bend increasingly north in track due to a developing western Atlantic ridge weakness associated with an upper trough and surface frontal system to emerge from eastern Canada and the northeastern US. Upper winds will also play a role in steering as Erin is likely to be strong/ tall in the long range. As such models currently project the mid-ocean upper vortex (near 32N-50W) to merge with the current eastern Caribbean inverted upper trough... creating a tropical upper vorticity band northwest of Erin that will help with the increased north angle toward day 5. Just after day 5... the models appear to agree on enough upstream upper ridging that cuts off the tail of the western Atlantic upper trough into a mid-latitude east-west band of upper vorticity around 35N latitude. In this solution... the warm core upper anticyclone of Erin helps amplify the cool-core mid-latitude upper vorticity band into an upper trough that pulls Erin north... and the pressure-dropping eastern divergence zone of the upper trough helps expand the size of Erin. If the current long range model trends hold... we would be dealing with an increasingly larger tropical cyclone angling toward Bermuda's vicinity.

Regarding intensity... currently forecasting brisk strengthening into a hurricane through 48 hours as Erin recovers in lower concentrations of dry Saharan air and tracks into warmer waters. I slow the intensification rate after 48 hours as Erin begins interaction with the aforementioned tropical latitude upper vorticity band. This band will likely not be strong enough to inhibit intensification... rather it may dampen it by muffling the upper outflow of the tropical cyclone during the initial interaction. Then after Erin weakens the east part of the cool-core upper vorticity band with its thunderstorm latent heat release... the remainder western part may impart some light southerly shear.

Erin is likely to produce surf reaching the northeastern Caribbean Islands by Friday and the early part of the weekend. Bermuda is then likely to see surf during the late part of the weekend into early next week.

******Infohurricanes.com forecast. Visit hurricanes.gov (hurricanes dot gov) for official forecast*********

0 Hr Position (0000Z Aug 13)... 45 mph maximum sustained wind tropical storm moving into the central tropical Atlantic while centered at 16.7N-40.1W

IOH 24 Hr Forecast (0000Z Aug 14)... 60 mph maximum sustained wind tropical storm centered in the central tropical Atlantic at 16.2N-46W

IOH 48 Hr Forecast (0000Z Aug 15)... 75 mph maximum sustained wind hurricane centered in the central tropical Atlantic at 17N-51W

IOH 72 Hr Forecast (0000Z Aug 16)... 80 mph maximum sustained wind hurricane centered east of the northern Lesser Antilles at 18N-55.5W

IOH 96 Hr Forecast (0000Z Aug 17)... 85 mph maximum sustained wind hurricane centered just northeast of the northern Lesser Antilles at 19.5N-59.8W

IOH 120 Hr Outlook (0000Z Aug 18)... 90 mph maximum sustained wind hurricane centered in the western Atlantic at 21.5N-61.5W

*****National Hurricane Center (hurricanes.gov) official forecast of 11 PM EDT***********************

5-Day Position (0000Z Aug 18)... 115 mph maximum sustained wind major hurricane centered well north-northeast of the Dominican Republic at 22.5N-66.5W

AREA OF INTEREST #14... The small tropical low that was in the open central Atlantic late Sunday/ early Monday proceeded to degenerate into a southwest to northeast surface trough. The southwestern part of the surface trough contains the original spin which has continued west under the influence of the western Atlantic surface ridge and has reached 25N-65W as of 0000Z tonight. The northeastern part of the surface trough was enhanced by the eastern divergence zone of the mid-ocean upper vortex near 32N-50W which proceeded to develop into a new spin... and prior to the NHC dropping this area of interest in their tropical weather outlook they relocated the initial position of the disturbance to the new spin. The new spin has already whirled into a position below the parent mid-ocean upper vortex where upper divergence is lacking... and the upper vortex is not cold enough to allow for instability and thunderstorms and hence it has been dropped from the NHC tropical weather outlook. Going forward the spin of interest continues north into the open north Atlantic while embedded in the flow between the Atlantic surface ridge to the east and area of interest #15 to the west which then becomes replaced by the large scale upper trough/ surface frontal system to approach from eastern Canada and the northeastern US. In the next 24 hours the forecast position is still over warm waters... however the nearby north Atlantic upper vorticity band along 40N latitude settles over the forecast position and continues to suppress upper outflow potential/ thunderstorm potential. Then by 48 hours the forecast position is over waters below 26 deg C. Therefore this is my planned final statement on this area of interest on this blog as tropical development is no longer expected.

Regarding the aforementioned original spin that is near 25N-65W as of this writing... it is likely to drift northwest into the waters between North Carolina and Bermuda while gravitated toward the tail end of the surface front that will be departing the northeastern US and eastern Canada... before it then loses its identity near/ along the front. Should it develop an increase in thunderstorms in low shear/ upper outflow prior to merging with the front... will be upgrading it to an area of interest with a different number as this area of interest number is tied to the other spin associated with the mid-ocean upper vortex as discussed in the previous paragraph.

******Infohurricanes.com outlook. Visit hurricanes.gov (hurricanes dot gov) for official outlook***********

IOH 24 Hr Outlook (0000Z Aug 14)... 0% chance of tropical cyclone formation (central Atlantic near 38N-50W)

*****National Hurricane Center (hurricanes.gov) official outlook as of 2 AM EDT***********************

Not in the official outlook

AREA OF INTEREST #15... The frontal low in the northwestern Atlantic has whirled northwest while caught in the flow on the north side of a cut-off upper vortex that has settled into the region. Within the last 48 hours the National Hurricane Center brought back this area of interest into their tropical weather outlook after previously having the frontal low in its outlook from August 3 to 8 back when the frontal low was close to the mid-Atlantic United States coast. Indeed the fronts attached to the low have been downgraded to surface troughs while the system has lost airmass contrasts... a step towards tropical development. Moreover their was an increase in showers and thunderstorms just west of center that lasted through Tuesday afternoon. For tonight the shower and thunderstorm activity has decreased as it wraps into the south side of the surface circulation.

The overhead upper vortex is expected to shift north in the next 24 hours due to the approach of the current central Canada upper trough. As such the surface low... which is currently under the north side of the upper vortex... will quickly finishing whirling toward the center of the north-moving upper vortex then drift north into cooler waters while following the vortex. Combined with the fact that shower and thunderstorm activity has decreased... time is running out for transition of the surface low into a subtropical cyclone and this is my planned final statement on this area of interest on this blog with the assumption this feature will no longer be in the NHC tropical weather outlook by the time I release my next update. Notable impacts to Nova Scotia from the approaching surface low are unlikely as it did not have the opportunity to gain strength beforehand through the tropical process (where thunderstorms develop a warm core upper outflow layer that helps drop surface pressures).

******Infohurricanes.com outlook. Visit hurricanes.gov (hurricanes dot gov) for official outlook***********

IOH 24 Hr Outlook (0000Z Aug 14)... 0% chance of subtropical cyclone formation (south-southeast of Nova Scotia near 41.5N-61.5W)

*****National Hurricane Center (hurricanes.gov) official outlook as of 2 AM EDT***********************

Formation chance through 48 hours... 10%

Formation chance through 7 days... 10%

AREA OF INTEREST #17... The surface trough of low pressure that was over the eastern Gulf of America continued to produce thunderstorms over the last 48 hours... and the NHC did mention this feature briefly in their tropical weather outlook. The maximum spin of the trough proceeded northwest and made landfall in southeastern Louisiana this past afternoon/ early evening while steered by the surface ridge that recently moved into the western Atlantic from the coastal northeastern US... and the associated thunderstorms produced heavy rainfall across southeastern Louisiana and southern Mississippi before largely dissipating in recent hours. Going forward the remains of the surface trough are likely to turn northeast across the southeastern United States and then possibly offshore western Atlantic waters while gravitated toward the tail end of the surface cold front to descend from Canada and the northeastern US. It is likely the remains will lose identity along the front... therefore any heavy rainfall that occurs across the southeastern United States will be attributed to the front rather than this area of interest. In the event the remains retain some sort of identity along the front as a mid-level or surface spin maximum... it is not likely to re-develop in a tropical manner when it reaches the offshore western Atlantic waters as the parent upper trough associated with the front leaves behind an east-west band of upper vorticity along 35N latitude that would induce westerly shear unfavorable for tropical development. Therefore this is my planned final statement on this area of interest as it is no longer at risk of tropical development.

******Infohurricanes.com outlook. Visit hurricanes.gov (hurricanes dot gov) for official outlook***********

IOH 24 Hr Outlook (0000Z Aug 14)... 0% chance of tropical cyclone formation (northern Mississippi near 34N-89.5W)

*****National Hurricane Center (hurricanes.gov) official outlook as of 2 AM EDT***********************

Not in the official outlook

AREA OF INTEREST #18... Quick forming tropical disturbance emerges in the western Caribbean and has already been introduced into the National Hurricane Center tropical weather outlook... this will be the eighteenth tropical Atlantic area of interest tracked on this site this year. The inverted upper trough that was in the central Caribbean has retrograded into the western Caribbean and proceeded to weaken due to prolonged isolation from high-latitude cold air. By early Tuesday a tropical disturbance began in earnest in the western Caribbean waters offshore of Nicaragua and Honduras as a small upper anticyclone expanded in the wake of the weakening inverted upper trough... the upper outflow of which supported an eruption of thunderstorms and associated surface trough of low pressure. Noting by 1200Z and 1800Z Tuesday... the NHC in their TAFB surface analysis began treating the surface trough as a tropical wave of low pressure... either way the surface trough/ tropical wave has been visible in satellite pictures as a swirl moving briskly west-northwest while the thunderstorms stayed off to the east and decayed. The inability of the thunderstorms to stay coupled with the surface spin is likely due to the spin catching up to the inverted upper trough where upper divergence/ outflow is lacking. However during the forecast period the inverted upper trough arcs to the north and away while gravitated toward the current eastern US upper vorticity... allowing for upper outflow potential to return over the disturbance after it crosses the Yucatan peninsula and enters the Bay of Campeche/ southwestern Gulf of America. Currently agree with the NHC's low 20% chance of tropical cyclone formation as the models do not develop this area of interest... higher odds will be warranted in future updates should this system re-develop persistent organized thunderstorm activity and/ or the models begin to pickup on this area of interest and develop it.

Upper convergence between upper southeasterlies on the northeast side of the inverted upper trough and easterlies on the south side of the mid-latitude upper ridge axis in the region will support a westward expansion of the western Atlantic surface ridge into the Gulf... keeping the forecast track of this area of interest on a steady west-northwest heading across the Yucatan peninsula... the Bay of Campeche and southwestern Gulf of America... and then into its final landfall with northeastern Mexico. Should thunderstorms re-develop with this disturbance later today... that could spell heavy rainfall with flash flooding potential across the Yucatan peninsula. Interests across northeastern Mexico... specifically northern Veracruz... Tamaulipas... and the adjacent inland provinces to the west... should be aware of possible heavy rainfall/ flash flooding risk from this disturbance for Friday. The potential for gusty winds and surf toward the coast is currently low due to the currently low odds of tropical cyclone formation... however interests along coastal northeastern Mexico should monitor this disturbance in case its development escalates when it crosses the southwestern Gulf/ Bay of Campeche waters on Thursday.******Infohurricanes.com outlook. Visit hurricanes.gov (hurricanes dot gov) for official outlook***********

IOH 24 Hr Outlook (0000Z Aug 14)... 0% chance of tropical cyclone formation (Mexico's eastern Bay of Campeche coast near 19.5N-91W)

IOH 48 Hr Outlook (0000Z Aug 15)... 20% chance of tropical cyclone formation (southwestern Gulf of America near 21.5N-95.2W)

IOH 72 Hr Outlook (0000Z Aug 16)... 0% chance of tropical cyclone formation (northeastern Mexico near 23.8N-99W)

*****National Hurricane Center (hurricanes.gov) official outlook as of 2 AM EDT***********************

Formation chance through 48 hours... 10%

Formation chance through 7 days... 20%

...COMPUTER MODEL SUMMARY...

Source...Florida State University Experimental Forecast Tropical Cyclone Genesis Potential Fields (http://moe.met.fsu.edu/tcgengifs/).

1200Z (Aug 12) CMC Model Run...

**For Tropical Storm Erin... no strengthening until center reaches 19N-54W at 84 hours... gains hurricane strength at a position just north of the northern Lesser Antilles at 120 hours... through 168 hours turns increasingly north into the waters south of Bermuda while becoming a larger and stronger hurricane

**For area of interest #14... no development shown

**For area of interest #15... northwest Atlantic surface low accelerates north-northeast into southwestern Newfoundland through 48 hours while losing identity to low pressure field of approaching eastern Canada frontal system

**For area of interest #17... surface trough makes landfall over central US Gulf coast at 12 hours... becomes entangled with upper trough crossing eastern Canada and northeastern US and as such moves east-northeast across the southeastern US and into waters east of North Carolina by 72 hours while transitioning into a frontal low supported by divergence at the southeast end of the upper trough... frontal low drifts east to the waters west of Bermuda through 144 hours without tropical development... shortly thereafter loses identity to low pressure field of Erin incoming from the southeast

**For area of interest #18... no development shown

**Tropical wave emerges from west coast of Africa at 54 hours and becomes a tropical low just southwest of the Republic of Cabo Verde Islands at 114 hours... the tropical low opens back to a wave while crossing 40W longitude at 168 hours

**Additional tropical wave emerges from west coast of Africa at 144 hours... becomes a large tropical low centered just offshore of Africa and near 15N-19.5W by 168 hours

1200Z (Aug 12) ECMWF Model Run...

**Checked this ECMWF model run at tropical tidbits as the above-mentioned source had data from several forecast timestamps missing (https://www.tropicaltidbits.com/analysis/models/?model=ecmwf&region=atl&pkg=mslp_pcpn&runtime=2025081212&fh=-3)

**For Tropical Storm Erin... gradually intensifies into a hurricane through 99 hours while reaching waters just northeast of the northern Lesser Antilles... through 168 hours turns increasingly northwest and reaches 26.5N-68W while becoming a larger and stronger hurricane

**For area of interest #14... no development shown

**For area of interest #15... northwest Atlantic surface low accelerates north-northeast and passes just offshore of the eastern tip of Nova Scotia by 42 hours... while making landfall on the southwest coast of Newfoundland at 48 hours loses identity to low pressure field of approaching eastern Canada frontal system

**For area of interest #17... no development shown

**For area of interest #18... no development shown

**Tropical wave emerges from west coast of Africa at 132 hours... becomes a large tropical low centered just east of the Republic of Cabo Verde Islands at 156 hours... centroid of tropical low positioned just southwest of the islands at 168 hours

1800Z (Aug 12) GFS Model Run...

**For Tropical Storm Erin... gains hurricane strength near 19N-54.5W at 78 hours... increasingly turns north then north-northeast while becoming a larger and stronger hurricane and reaches the waters just east-southeast of Bermuda by 168 hours

**For area of interest #14... no development shown

**For area of interest #15... northwest Atlantic surface low accelerates north-northeast and while positioned just offshore of the eastern tip of Nova Scotia at 33 hours loses identity to low pressure field of approaching eastern Canada frontal system

**For area of interest #17... no development shown

**For area of interest #18... no development shown

**Tropical wave emerges from west coast of Africa at 123 hours... becomes a north-south oblong tropical low just southwest of the Republic of Cabo Verde Islands at 156 hours... centroid of tropical low positioned near 13N-28W at 168 hours

1800Z (Aug 12) NAVGEM Model Run...

**For Tropical Storm Erin... becomes a hurricane while reaching 19N-56W at 96 hours... while curving increasingly north into the waters just south-southeast of Bermuda becomes a larger and stronger hurricane

**For area of interest #14... no development shown

**For area of interest #15... northwest Atlantic surface low accelerates north-northeast and while positioned just offshore of the eastern tip of Nova Scotia at 36 hours loses identity to low pressure field of approaching eastern Canada frontal system

**For area of interest #17... no development shown

**For area of interest #18... no development shown