*******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 16 2019 2:20 PM EDT...
<<Insert Birdseye view Chart Here>>
The emerging area of disturbed weather in the central tropical Atlantic has become introduced into the National Hurricane Center 5-day tropical weather outlook due to some potential for tropical cyclone formation. See area of interest #1 section below for additional details.
AREA OF INTEREST #1...The long-awaited central tropical Atlantic disturbance appears to be materializing as the latest upper trough in the region sharpens in response to amplifying upper ridging over the Caribbean and western Atlantic bolstered by the warm sector of the frontal low intensifying just offshore of the southeastern United States. The sharper upper trough is producing a stronger area of upper divergence on its east side that has increased the squalls of showers and thunderstorms in the central tropical Atlantic as well as the consolidation of a surface trough of low pressure. Based on the latest ASCAT-A descending pass...it appears the maximum spin of the surface trough is near 16N-54W...which places the surface trough on the west side of the squally weather as the upper trough is also shearing the thunderstorm squalls eastward from the surface trough. My forecast track in the outlook below is based on this current position...and shows this disturbance curving increasingly northwestward and then northward while rounding the west side of the Atlantic subtropical ridge and east side of the frontal low offshore of the southeastern US. After this frontal low ejects northward into Atlantic Canada during the middle of the forecast period...the upper trough currently over the western US will have arrived into the western Atlantic and produced another frontal low...which guarantees this disturbance will continue northward...followed by a northeastward acceleration by 120 hours as the cold front of the second frontal low absorbs this disturbance. The usually conservative Euro (ECMWF) model support has significantly increased over the last 24 hours and suggests this disturbance may become a hurricane before becoming absorbed by the cold front. Meanwhile the also-reliable GFS shows no tropical cyclone formation...and the NAVGEM which had been in days prior showing a hurricane now still shows no development. I speculate the recent Euro model solutions maybe why this disturbance has been introduced into the National Hurricane Center 5-day tropical weather outlook today. I think whether or not this disturbance develops into a tropical cyclone will depend on whether or not this disturbance produced enough thunderstorm latent heat release to defeat the cold core shearing central Atlantic upper trough just to the west...and eastern Atlantic cut-off upper vortex which will soon approach from the northeast while pushed by the aforementioned upper ridge. Therefore I show peak odds of development of only 10% at this time due to the lackluster intensity of thunderstorms in the latest colorized infrared satellite...and show the peak odds between 72 and 96 hours as this is when this disturbance if it survives the short term effects of the aforementioned cold core upper vorticity will be moving into the lower shear of the aforementioned upper ridge...but the shear may not be completely absent if the central Atlantic upper trough still lingers by that timeframe and if the southwesterly winds of the absorbing cold front's upper trough impenges too much from the west.
******Infohurricanes.com outlook. Visit hurricanes.gov (hurricanes dot gov) for official outlook***********
IOH 24 Hr Outlook (1200Z Nov 17)...0% chance of tropical cyclone formation (central Atlantic near 17N-54W)
IOH 48 Hr Outlook (1200Z Nov 18)...0% chance of tropical cyclone formation (central Atlantic near 20N-57.5W)
IOH 72 Hr Outlook (1200Z Nov 19)...10% chance of tropical cyclone formation (central Atlantic near 24N-61W)
IOH 96 Hr Outlook (1200Z Nov 20)...10% chance of tropical cyclone formation (central Atlantic near 27.5N-61W)
IOH 120 Hr Outlook (1200Z Nov 21)...0% chance of tropical cyclone formation (absorbed by cold front near 32N-55W)