MY 2024 ATLANTIC HURRICANE SEASON BIRDSEYE VIEW POST #38

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

...WEDNESDAY JULY 10 2024 2:54 PM EDT...

See area of interest #10 section below for an update on the tropical wave of low pressure that is moving into central Mexico from the Bay of Campeche. Elsewhere... a tropical disturbance appears to be materializing offshore of the southeastern United States with the formation of a surface trough... and the tail end of the cold front being driven by ex-Beryl will add to this disturbance in the next 24 hours... see area of interest #11 section below for more information.

AREA OF INTEREST #10... The surface tropical wave of low pressure that was over the Bay of Campeche and Isthmus of Tehuantepec of southeastern Mexico has continued west across south-central Mexico and adjacent eastern Pacific waters. However it appears the wave has left behind a mid-level spin which has only recently made landfall over the northern Veracruz coast... confirmed by the CIMSS 850 mb vorticity product (https://tropic.ssec.wisc.edu/real-time/windmain.php?&basin=atlantic&sat=wg8&prod=vor&zoom=&time=). The original thunderstorm activity tied to the mid-level spin... which was over central Veracruz about 24 hours ago... dissipated overnight while renewed thunderstorm activity roared across the Isthmus of Tehuantepec... western Bay of Campeche... and into central and northern Veracruz as well as southern Tamaulipas. However given that the southwest side of surface ridging building behind ex-Beryl will be scooting the mid-level spin west-northwestward into east-central Mexico... tropical cyclone formation is no longer possible and this is my final statement on this area of interest. Final note... even though tropical cyclone formation has not occured periods of heavy rainfall with flash flooding potential are possible across east-central Mexico (northern and central Veracruz... southern Tamaulipas... and vicinity) within the next 24 hours.

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

IOH 24 Hr Outlook (1200Z Jul 11)... 0% chance of tropical cyclone formation (inland over east-central Mexico near 22N-99.5W)

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

Not in the official outlook

AREA OF INTEREST #11... A tropical disturbance is materializing offshore of the southeastern United States from a couple of surface features which will soon be merging together... the first being the surface cold front currently driven driven by ex-Beryl which will soon move into the waters offshore of the southeastern United States... the second being a new offshore surface trough with associated north-south thunderstorm axis that has been generated by divergence between the northwest side of upper vorticity approaching from the east and south side of the regional upper ridge axis. The thunderstorms are currently biased to the west side of the new surface trough due to easterly shear imparted by the south side of the upper ridge. Upper winds may become more conducive for tropical development of this new disturbance right around the time it makes landfall with the southeastern United States coast... and the NHC has added the disturbance as an area of interest in their tropical weather outlook. This marks the eleventh tropical Atlantic area of interest tracked on this site this year.

The atmosphere around this disturbance will undergo a complex evolution during the forecast period. In the upper-levels the lengthy upper trough currently supporting ex-Beryl splits into a northeastern trough that merges with a larger upper trough sliding across northern Canada... and a southwestern trough that hangs around the Great Lakes region of North America for a period of time... noting convergence on the back side of the northeastern upper trough builds a surface ridge in the vicinity of the northeastern US and Atlantic Canada. Meanwhile the aforementioned upper vorticity that approaches from the east eventually hooks north somewhere in the vicnity of the United States east coast while pulled in by the Great Lakes upper trough... and when the north side of the upper vorticity opens up while merging with the Great Lakes trough it will resemble another mid-latitude upper trough whose western suppressive convergence zone could negatively affect this tropical disturbance.

Regarding forecast track... the emerging global model consensus is that the disturbance does not become trapped between the Atlantic surface ridge and aforementioned northeastern US surface ridge... instead the emerging consensus shows the northeastern US surface ridge pushing the disturbance into the southeastern United States at some point (the outlier remains the CMC model which insists that the eastern divergence zone of the aforementioned upper trough feature near the US east coast creates a narrow weakness between the two surface ridges that allows for the disturbance to move along the Carolina coast then out to sea). My forecast track in the outlook below is quasi-stationary over the next 24 hours as the offshore surface trough merges with the cold front being driven into the region by ex-Beryl... followed by a westward drift into the southeastern US beyond that time while in agreement with the emerging model consensus. Regarding odds of tropical cyclone formation... I agree with the current NHC outlook of low odds due to potential exposure to suppressive upper convergence on the west side of the upper trough feature that sets up along the US east coast... and even if upper winds are more favorable for development the surface low pressure field of the disturbance initially starts out broad while becoming a merger between two surface features... and thus may never consolidate into a well-defined center needed for cyclone formation. Albeit at around 60 hours I briefly increase odds of tropical cyclone formation to 20% when this system drifts west away from the US east coast upper trough feature and directly below the regional upper ridge axis (area of lowest shear and maximal upper outflow) as it makes landfall. Regardless of tropical cyclone formation or not... this disturbance has potential to produce periods of heavy rain across the southeastern United States through late this week and into the weekend... incidents of flash flooding in the region cannot be ruled out.

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

IOH 24 Hr Outlook (1200Z Jul 11)... 10% chance of tropical cyclone formation (offshore of the southeastern United States near 30.5N-78W)

IOH 48 Hr Outlook (1200Z Jul 12)... 10% chance of tropical cyclone formation (just offshore of Georgia near 31N-80W)

IOH 60 Hr Outlook (0000Z Jul 13)... 20% chance of tropical cyclone formation (coastal Georgia near 31.2N-81.2W)

IOH 72 Hr Outlook (1200Z Jul 13)... 0% chance of tropical cyclone formation (south-central Georgia near 31.5N-83W)

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

Formation chance through 48 hours... 10%

Formation chance through 7 days... 10%

...COMPUTER MODEL SUMMARY...

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

0000Z (Jul 10) CMC Model Run...

**For area of interest #10... no development shown

**For area of interest #11...Tail end of cold front attached to ex-Beryl develops into another frontal low over northeastern South Carolina at 36 hours due to split flow upper divergence between the flow ahead of the upper trough supporting ex-Beryl and northwesterly upper winds flowing into upper vorticity offshore of the southeastern US... through 60 hours the original surface center shifts southwestward into southeastern Georgia while dissipating under suppressive upper convergence on the west side of the offshore upper vorticity while divergence on the east side of the upper vorticity produces another possibly more tropical and broad surface low pressure area offshore of the Georgia/South Carolina border... the potentially tropical surface low continues north-northeast across the North Carolina Outer Banks through 84 hours... through 108 hours the surface low accelerates east-northeast across the northwest Atlantic while weakening to a surface trough that gradually loses identity to frontal system approaching from eastern Canada.

0000Z (Jul 10) ECMWF Model Run...

**For area of interest #10... no development shown

**For area of interest #11... tail end of cold front attached to ex-Beryl develops into a broad surface low offshore of South Carolina at 36 hours while supported by anticyclonic outflow between offshore upper vorticity to the southeast and upper trough supporting ex-Beryl to the northwest... through 60 hours the surface low drifts west-southwest to the waters offshore of Georgia due to steering surface ridge that builds in wake of ex-Beryl which allows it to escape the suppressive upper convergence on the west side of the offshore upper vorticity approaching from the east... surface low then makes landfall on coastal Georgia and South Carolina as a surface trough by 84 hours which then dissipates shortly thereafter

0600Z (Jul 10) GFS Model Run...

**For area of interest #10... no development shown

**For area of interest #11... tail end of cold front attached to ex-Beryl develops into a broad surface low just offshore of South Carolina coast at 27 hours while supported by anticyclonic outflow between offshore upper vorticity to the southeast and upper trough supporting ex-Beryl to the northwest... through 48 hours the surface low drifts west-southwest into the coast of Georgia due to steering surface ridge that builds in wake of ex-Beryl which allows it to escape the suppressive upper convergence on the west side of the offshore uppr vorticity approaching from the east... as a weak surface low/trough continues west across the interior southeastern US and reaches Mississippi through 96 hours... dissipates at this location through 120+ hours.

0600Z (Jul 10) NAVGEM Model Run...

**For area of interest #10... no development shown

**For area of interest #11... tail end of cold front attached to ex-Beryl develops into a surface low over southeastern North Carolina at 30 hours while supported by anticyclonic outflow between offshore upper vorticity to the southeast and upper trough supporting ex-Beryl to the northwest... drifts west-southwest while becoming a rather broad surface low covering the Carolinas and Georgia through 60 hours after which time it dissipates.