Dr. Levi Cowan
@tropicaltidbits
Owner/developer of . PhD in meteorology from FSU. Opinions are mine alone. Follow for expert, factual, no-hype hurricane analysis
Gradual pressure falls are being observed at Buoy 42036 at about 28.5N, 84.5W, indicating that slow organization likely continues.
#TD2 remains broad and weak for now, with dry air entrainment evident west of the circulation, clearly limiting the intensity and coverage of deep thunderstorms near the center of circulation.
🌀 Regardless, a period of heavy rains is expected to spread through southeast #Texas, #Louisiana, and other northern gulf coast states. The NWS Weather Prediction Center outlines a wide swath of slight to moderate risk for excessive rainfall and flash flooding mid-week.
🌀 Ensemble guidance outlines this scenario as a distinct but minority possibility, with most members either keeping the disturbance inland over Texas or otherwise failing to organize. The National Hurricane Center currently puts odds of storm development at 30%.
🌀 The associated subtropical jet will impose westerly winds aloft, pushing thunderstorm activity offshore, possibly dragging the disturbance back over water off the Texas coastline. While the system would be sheared, time over water would open an opportunity for a brief tropical cyclone to form.
Tropical Depression Two-E has formed just south of Guerrero, #Mexico. The storm is expected to quickly move inland on Monday, bringing heavy rains, flash flooding, and mudslide hazards to the region.
The Eastern Pacific is waking up, with two tropical cyclones expected to develop near the coastlines of #Mexico and #CentralAmerica over the next couple days, bringing primarily heavy rainfall and flash flooding hazards to the region.
🧵(4/5) Other models, notably most AI-based models, show a less amplified upper-level pattern with northwesterlies dominating the region. This would suppress moisture transport & the migration of the monsoonal vorticity pocket. The result is much less cyclone activity in the Gulf on these model runs.
🧵(3/5) However, much will depend on support from large-scale flow to the north. In some models, an amplified upper-level trough digs over the Gulf, dredging tropical moisture northward and assisting migration of the monsoon lobe into a position that facilitates cyclone formation over the Gulf.
🧵(2/5) The eastern lobe of the monsoon trough, perhaps even taking the form of a weak gyre, is expected to attempt to migrate northwestward into the western Caribbean or southern Gulf, a scenario which often creates potential for messy cyclones to develop and ultimately approach the Gulf coast.
🧵(1/5) Some possibility of tropical activity in the Gulf exists beginning late next week. The Central American monsoon is becoming active as multiple equatorial waves (MJO, Kelvin, Rossby) overlap next week near 90W longitude.
Tropical Storm #Andrea has formed over the North Atlantic, the first of the Atlantic season. Andrea is already moving into cold waters and will be short-lived, expected to dissipate over the next 24 hours. Andrea is not a threat to any populated areas.
The Eastern Pacific is getting going with their first Tropical Storm of the season, named #Alvin 🐿️ The NHC predicts a track northward towards northern Mexico, but fortunately, Alvin will hit some cold water on its way there, likely causing it to mostly dissipate prior to arrival.