*******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.*********
...UPDATE...JUNE 26 2024 3:55 PM EDT...
The following is an updated birdseye view chart of the Atlantic basin (satellite image only included at this time... the corresponding surface and upper air charts will be added later tonight):

Update as of 11:00 PM EDT... the surface and upper air charts have been added as seen above.
The Atlantic tropics are heating up as a few changes have already occurred since my previous full update. My next full update is schedule for tonight... however noting the following in this short update:
(1) Area of Interest #8... continues to be characterize as a fast-moving low-amplitude surface tropical wave of low pressure which has already made its way into the central Caribbean... faster than my previous forecasts. As such this system will be arriving early into Central America... southeastern Mexico... and southwestern Gulf of Mexico earlier... and its potential for tropical development is decreasing as the unfavorable and slowly decaying Gulf upper vorticity will now be in position when this wave arrives early. However any heavy rainfall this wave produces across western Central America and southeasern Mexico in the days ahead could be detrimental and cause flooding hazards... as grounds here are already saturated from the passage of previous tropical systems.
(2) Area of Interest #9... tropical wave of low pressure in the eastern tropical Atlantic... this is a new area of interest recently added into the NHC official outlook as computer models have quickly switched to now develop this wave as it moves across the eastern and central tropical Atlantic... and into the southern Lesser Antilles through day 5. Interests in the southern Lesser Antilles should begin monitoring the progress of this tropical wave... will have more information on this situation in my next full update tonight.
(3) A cut-off upper vortex has been left behind over the southeastern United States while the parent upper trough has moved on into the northwest Atlantic. This cut-off feature is forecat to accelerate northeast into the waters between Bermuda and Atlantic Canada in the next 48 hours... where its eastern divergence zone could trigger a surface tropical disturbance over the narrow ribbon of warm Gulf stream waters in this region. A new area of interest may need to be declared for this region of the Atlantic in future updates.
(4) Another tropical wave of low pressure is forecast to emerge from the west coast of Africa and behind area of interest #9 in the next 48 hours... and some computer models are also latching on to developing this wave. As such the future wave may also need upgrading area of interest status in future updates.
...TUESDAY JUNE 25 2024 10:38 AM EDT...

See area of interest #8 section for information on the current Lesser Antilles tropical wave of low pressure which may later develop as it moves across the Caribbean Sea in the days ahead. Elsewhere... upper winds in the eastern and central tropical Atlantic (between Africa and the Lesser Antilles) will remain favorable for tropical activity over the next few days due to low shear and outflow provided by the tropical upper ridge axis in the region. However recent tropical waves of low pressure passing through the region have not developed due to ongoing outbreaks of dry Saharan air kicked up by each wave when they depart Africa. However there is a developing model consensus that in 72+ hours the dry Saharan air may let up enough to allow for tropical development in the eastern or central tropcial Atlantic... as such a new area of interest may need to be declared in this region in future updates.
For the mid-latitudes of the Atlantic... the southern part of the current eastern US upper trough is forecast to seperate over the next 24 hours. Through 72 hours the upper trough fragment then moves northeast across the western Atlantic from the southeastern US and passes north of Bermuda in the flow ahead of the next upper trough now approaching from central Canada. There is a possiblity the eastern divergence zone of the upper trough fragment triggers a tropical area of interest over the narrow band of warm Gulf Stream waters between Bermuda and Atlantic Canada... and yet another tropical area of interest may need to be declared in this region in future updates should computer models converge on this idea and/or future satellite observations warrant.
AREA OF INTEREST #8... The currently strong Atlantic surface ridge has recently pushed a series of central Atlantic tropical waves of low pressure toward the southeastern Caribbean Sea. Each wave has been observed to slow down while reaching weaker steering at the southwestern periphery of the ridge... allowing the wave(s) behind it to catch up. As such two of the waves have recently merged over the southern Lesser Antilles island chain... since I was using the eastern of the two waves in the merger to mark this area of interest I am now relocating this area of interest further west to the position of the merged wave and my updated forecast track in the outlook below is adjusted accordingly. The National Hurricane Center within the last 24 hours has also added this area of interest into their tropical weather outlook as some model runs continue to recognize the wave's development potential underneath an expanding Caribbean upper ridge cell (environment of low shear and upper outflow) in the days ahead. Upper ridging in the Caribbean is currently suppressed toward western Central America by a lengthy string of upper vorticity across the Gulf of Mexico and western Atlantic. However the upper ridge is forecast to expand back across the Caribbean as much of the western Atlantic upper vorticity becomes swept away by the approaching upper trough currently over the eastern US in the next 24 hours... with the remainder Gulf of Mexico upper vorticity gradually decaying from prolonged isolation from high-latitude cold air (albeit the decay process is slowed while some upper vorticity is deposited over the Gulf by the current eastern US upper trough and also the next upper trough currently moving across central Canada... however enough decay still occurs through day 5 to allow the upper ridge to expand across the Caribbean). Although some favorable upper ridging expands over this area of interest in the next 24 hours with the aforementioned departure of the western Atlantic upper vorticity... by 48 hours this area of interest incurs southerly shear from the remainder Gulf of Mexico upper vorticity and this area of interest would need at least 24 hours to organize further based on its current satellite apperance... therefore I hold 0% odds of tropical cyclone formation for the first 48 hours. I pull odds of development above 0% for 72+ hours... when this system tracks near western Central America and across the western Caribbean... while this system potentially takes advantage of better upper winds as the Gulf upper vorticity continuously decays. At this time I agree with the NHC's 20% peak odds of development as not all models agree on developing this area of interest... and curiously the CMC/GFS consensus is to not develop this system in the western Caribbean but instead develop it in the Bay of Campeche in the longer range (toward day 7)... which could be questionable should the Gulf upper vorticity have too slow of a decay rate.
Through day 3 the forecast track is steady to the west-northwest due to an extension of the steering Atlantic surface ridge located toward the Florida peninsula (the surface ridge extension is supported by convergence beneath the aforementioned Gulf upper vorticity). By day 4 my track projection is bent more northward while this system rounds the southwest periphery of the Atlantic surface ridge system... and then by day 5 the track is bent back more westward as a surface ridge builds over the central US beneath the convergent back side of a passing North America upper trough.
Main concern for this area of interest is that it could produce heavy rains across western Central America and southeastern Mexico in the 3 to 7 day window... over grounds previously saturated by previous Atlantic tropical systems. This would result in a flood risk in this region.
******Infohurricanes.com outlook. Visit hurricanes.gov (hurricanes dot gov) for official outlook***********
IOH 24 Hr Outlook (0600Z Jun 26)... 0% chance of tropical cyclone formation (southeastern Caribbean Sea near 13N-69W)
IOH 48 Hr Outlook (0600Z Jun 27)... 0% chance of tropical cyclone formation (south-southwest of Haiti near 14N-74W)
IOH 72 Hr Outlook (0600Z Jun 28)... 10% chance of tropical cyclone formation (southwest of Jamaica near 14.5N-79.5W)
IOH 96 Hr Outlook (0600Z Jun 29)... 20% chance of tropical cyclone formation (south-southwest of the Cayman Islands near 17N-82.5W)
IOH 120 Hr Outlook (0600Z Jun 30)... 20% chance of tropical cyclone formation (east of the Belize/Mexico border near 18N-86W)
*****National Hurricane Center (hurricanes.gov) official outlook as of 8 AM EDT**************************
Formation chance through 48 hours... 0%
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/).
0000Z (Jun 25) CMC Model Run...
**For area of interest #8... tropical wave currently crossing the Lesser Antilles evolves into a tropical low over east coast of Honduras at 66 hours... tropical low makes landfall on north coast of Belize at 90 hours and emerges into the eastern Bay of Campeche at 102 hours... tropical cyclone formation suggested offshore of southern Tamaulipas at 132 hours with landfall and inland dissipation forecast for 144+ hours
**Tropical wave emerges from west coast of Africa at 78 hours and evolves into tropical low near 10N-36.5W at 156 hours
0000Z (Jun 25) ECMWF Model Run...
**For area of interest #8... no development shown
**Tropical wave emerges from west coast of Africa at 72 hours... evolves into tropical low near 11.5N-36.5W at 162 hours
0000Z (Jun 25) GFS Model Run...
**For area of interest #8... tropical wave currently crossing the Lesser Antilles crosses through the Caribbean Sea and Yucatan peninsula... emerges into the southern Bay of Campeche by 126 hours as a tropical low... through 150 hours tropical low drifts west into southern Veracruz with possible tropical cyclone formation before landfall... inland dissipation shown shortly thereafter
**Tropical wave currently emerging into the Atlantic from west coast of Africa evolves into tropical low near 10.2N-34.5W at 63 hours... compact tropical cyclone formation suggested near 9.8N-52.5W at 126 hours... compact tropical cyclone makes landfall on Trinidad at 159 hours then continues west-northwest across the northeast coast of Venezuela through 168 hours
**Tropical wave emerges from west coast of Africa at 72 hours... evolves into broad tropical low near 8N-38.5W at 144 hours... broad tropical low curves northwest to 10.5N-43W through 168 hours
**Current upper trough over the eastern US leaves behind fragment over the southeastern US over the next 24 hours... from 24 to 72 hours the upper trough fragment continues northeast across the western Atlantic in the flow ahead of the next major upper trough in the mid-latitude westerlies with the eastern divergence zone of the trough framgent triggering tropical cyclone formation near 35N-65W at 78 hours... tropical cyclone continues northeast to 38N-60W through 105 hours then drifts north-northeast toward the cooler waters south of Newfoundland through 132 hours where it dissipates
1200Z (Jun 24) NAVGEM Model Run...
**For area of interest #8... tropical wave currently crossing the Lesser Antilles evolves into broad tropical low east-northeast of Nicaragua and Honduras by 90 hours... the tropical low makes landfall at the Belize/Mexico border by 120 hours... continues west-northwest across the southern Yucatan peninsula and southwestern Gulf of Mexico through 168 hours as a large surface trough.
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