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*** No direct impacts from current systems in the tropics for Jacksonville/NE Fl./SE Ga. Gonzalo will, however, impact the Southern Lesser Antilles then will move into the Caribbean before dissipating... Hanna will move into Texas... Douglas will move across Hawaii Sunday (near the bottom of the post). ***
(1) the tropical wave/disturbance that’s been moving northwest across the Gulf of Mexico strengthened into tropical depression #8 Wed. evening & tropical storm Hanna Thu. evening & into the Atlantic season’s first hurricane early Saturday (avg. first Atlantic hurricane is Aug. 10). Hanna is the fastest ever to the ‘H’ name beating “Harvey” on Aug. 3, 2005. Hanna has continued to organize with intense bursts of convection & notable banding on satellite & radar imagery while well ventilated (outflow) over the top. Now that the storm is developing a central core & the center is stabilizing (had been jumping around in its formative stage), steady intensification should continue right up to a Southeast Texas landfall Sat. night while bending some to the southwest to the south of Corpus Christi & to the north of Brownsville. Hanna is the 4th named storm for July which is just short of the record of 5 set in 2005. Two named storms over the Atlantic Basin at the same time in July last happened in 2018 (Beryl & Chris). Other times since 2000 (Klotzbach): 2011, 2008 & 2005. Hanna will pretty quickly weaken Sunday inland over the Rio Grande Valley.
(2) low pressure over the Central Atlantic became tropical depression #7 Tue. & then tropical storm “Gonzalo” Wed. This is the fastest ever to the 7th named storm over the Atlantic beating “Gert” in 2005 by two days. The avg. date of the 7th named storm is not until Sept. 16th. The forecast track is rather straight forward the next few days thanks to an expansive Bermuda high over the Central Atlantic so a steady, rather fast westward movement turning a little northwest over the Caribbean. Gonzalo will move through the Southern Windward Islands through Saturday night. Hurricane recon has been finding a rather disheveled tropical cyclone likely due to dry mid & upper level air as well as increasing shear not to mention close proximity to Valenzuela. The official forecast is for Gonzalo to rather rapidly “spin down” once over the Caribbean leading to eventual dissipation or at least weakening into an open wave & regeneration is not anticipated. Some heavy & gusty squalls will affect the Southern Lesser Antilles Saturday, but there is not likely to be significant damage.
(3) Tropical waves - one strong one in particular - are now rolling off the coast of Africa. Long range forecast models show the potential for some development while making a long track across the tropical Atlantic through early Aug. “underneath” the broad & strong Bermuda high. This one could be a “trouble maker” & the first classic tropical cyclone from the deep tropics of the season. Forecast models, of course, are at odds with one another & sometimes at odds with themselves (from one cycle run to the next). It’s way too early to get too caught up in the modeling or to start to panic(!). The European has the system in the Western Caribbean by next weekend... the GFS is faster & has the system near Fl. by late in the upcoming week... & the UKMET is faster, stronger & more west so somewhat similar to the European.
(4) A little upper level disturbance/trough of low pressure looks like it’ll be left behind from Hanna over the weekend/early next week over the Northern Gulf of Mexico. While not particularly likely, it’s not out of the question, clusters of t’storms could fester with this disturbance helping to induce surface low pressure. IF so, this could be an area to watch for rather sudden/short term tropical development - anywhere from Louisiana to the Fl. Panhandle. Not a likely scenario but something to keep an eye on. The low will then emerge over the Western Atlantic by the middle of next week where there could also be some potential for tropical development as the low rides on out northeast over the Atlantic.
There has also been a rather persistent cluster of t’storms over/near the Bahamas tied to an upper level disturbance. No surface development is indicated or expected while the system moves north/northwest.
Overall.... it looks like a much more active Atlantic into at least the first 10 days of Aug. More on that further down - see “Velocity Potential Anomalies”.
Gonzalo is now moving away from the dry air in the water vapor image below but little else is favorable (land & shear):
E. Atlantic tropical wave/disturbance spaghetti plots:
Meanwhile... “velocity potential anomalies” map below shows why we could - & should - see more tropical activity over both the E. Pacific & Atlantic in the coming weeks. The green lines indicate “upward” vertical velocities which are shown to be in a narrow but strong corridor spreading from the Eastern Pacific into the Atlantic Basini. This upward motion in the atmosphere often correlates with increased t’storm activity & sometimes tropical development & is right in concert with the development of tropical cyclone Douglas over the E. Pacific. I would expect to see at least a couple of named storms pop over the Atlantic Basin between now & August 10th & has likely already helped with the development of Hanna over the Gulf of Mexico.
Atlantic dust continues to spill west off of the Saharan desert over the E. Atlantic. Tropical waves continue to “fester” along the south edge of the dust & have the potential to thrive once away from the dust.
2020 names..... “Isaias” is next on the Atlantic list (names are picked at random by the World Meteorological Organization... repeat every 6 years... historic storms are retired (Florence & Michael last year) & Dorian is certain to be retired from the ’19 list....
Mid & upper level wind shear (enemy of tropical cyclones) analysis (CIMMS). The red lines indicate strong shear of which there is plenty across most of the Atlantic at the moment:
Water vapor imagery (dark blue indicates dry air):
Deep oceanic heat content is extreme over the NW Caribbean:
Sea surface temp. anomalies:
SE U.S. surface map:
Surface analysis centered on the tropical Atlantic:
Surface analysis of the Gulf:
In the East Pacific.... “Douglas” became a powerful Cat. 4 hurricane over the East Pacific Thu. after rapidly intensifying but has peaked... is leveling off.... & will now gradually weaken. Douglas should be near Hawaii by late in the weekend & may still be a formidable tropical storm or even low end Cat. 1 hurricane with the eye projected to go just north of the Big Island Sunday. Hurricane WATCHES are in effect.
Global tropical activity:
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