An intensifying Tropical Storm Gamma was barreling ashore in Mexico’s Yucatan Peninsula early Saturday afternoon with top winds of 70 mph, just below hurricane strength. Gamma was bringing heavy rains in excess of an inch per hour to portions of the Yucatan Peninsula on Saturday, and flash flooding from these torrential rains is the greatest threat from the storm. Some 24-hour rainfall amounts from Gamma at Weather Underground personal weather stations as of noon EDT Saturday included:
Puerto Morelos, Mexico: 15 inches
Cozumel, Mexico: 11.15 inches
Cancun, Mexico: 5.64 inches
Roatan, Honduras: 4.79 inches
The 2020 parade of record-early named storms continues
Gamma developed into a tropical storm on Friday evening, and its October 2 arrival marked the earliest date that any Atlantic season has produced its 24th tropical storm, topping the record held by Beta from October 27, 2005.
With the Atlantic hurricane season three-quarters done, we’ve already had 24 named storms, eight hurricanes, two intense hurricanes, and an accumulated cyclone energy (ACE) index of 106 (24% above average for the date). Only one Atlantic hurricane season since 1851 has had more named storms during an entire season: 2005, with 28 named storms. According to Colorado State University hurricane scientist Phil Klotzbach, the averages for this point in the season are nine named storms, five hurricanes, two intense hurricanes, and an ACE index of 85.
Gamma’s landfall in Mexico gives the “Greek” storms of 2020 three consecutive landfalls, along with Alpha in Portugal and Beta in Texas. The only other year with Greek-named storms, 2005, also had three of these late-season storms make landfall: Alpha, Beta, and Gamma, all in the Caribbean.
Forecast for Gamma
Conditions for development were less favorable on Saturday than on Friday, with wind shear a moderately high 15-20 knots and a drier atmosphere (a mid-level relative humidity near 60%). Despite these factors, satellite images showed that Gamma continued to grow more organized right up until landfall, with an eye beginning to appear.
The trough of low pressure pulling Gamma to the northwest is expected to move eastwards on Sunday and leave the storm behind, putting Gamma in an area of weak steering currents. As a result, Gamma’s forward motion is expected to slow to less than 5 mph Saturday night through Monday, resulting in very heavy rains across much of Mexico’s Yucatan Peninsula, portions of Central America, and western Cuba. The current model consensus is that a weak ridge of high pressure will build to the north of Gamma on Sunday and Monday, forcing the storm to move west or west-southwest Monday through Wednesday.
Conditions for development of Gamma will become more hostile on Sunday and Monday, when high wind shear of 20-30 knots and dry air over the Gulf of Mexico will interfere with development, as will land interaction with the Yucatan Peninsula. Because of these obstacles, the top intensity models generally show weakening of Gamma over the next five days.
Central Caribbean tropical wave 92L may develop
Further complications on predicting Gamma’s track may arise by Monday or Tuesday as another tropical wave, now moving through the central Caribbean, arrives in the western Caribbean and potentially develops into a tropical depression or tropical storm. This wave, which was designated 92L by NHC on Saturday morning, was located south of Haiti on Saturday afternoon and was moving west-northwest at about 10 mph. Satellite images showed the wave had a modest amount of heavy thunderstorms that were poorly organized and the wave was under a moderate 10-15 knots of wind shear, which was slowing development.
When 92L reaches the western Caribbean on Monday, the shear is expected to drop to a low 5-10 knots, ocean temperatures beneath its path will warm to 30 degrees Celsius (86°F), and 92L will be in a moist environment — conditions that favor development. The top three models for predicting tropical cyclone genesis were giving modest support for development to occur on Monday or Tuesday in the western Caribbean, and in an 8 a.m. EDT Saturday Tropical Weather Outlook, the National Hurricane Center gave 92L two-day and five-day odds of development of 20% and 50%, respectively.
There were two other areas of interest in the central Atlantic that were being given low odds of development by NHC on Saturday morning, but neither of these two systems are a threat to any land areas.
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Posted on October 3, 2020 (12:44pm EDT).
good rain around here this morning, its been kinda dry lately… http://radar.weather.gov/lite/N0R/TBW_loop.gif?9a6a6dd51097704144416d63b5adfe17
And the 21z 850mb…..
Morning everyone….we have some conflicting steering winds for Gamma right now which is causing the stand-off…..forecasted 21z 500mb level winds still favor a NNE pattern and the 850mb level winds favor a SW pattern….see attached for 500mb….
this one after Gamma is maube the one we around the gulf need to watch..https://www.baynews9.com/content/dam/News/2020/10/03/next_low.jpg
bullpucky … is there a way to report this garbage? AFAIK Dems are behaving, I couldn’t say the same for JE.
My latest birdseye view post of the Atlantic tropics up at this link, discuss how Gamma could become a strong hurricane in the SW Gulf over the next few days, and also the other areas of interest peppering the Atlantic tropics elsewhere.
yes we need to stay alert this month for sure
northern gulf keep a watch on the 2nd Low pressure system…..https://www.tropicaltidbits.com/analysis/models/gfs/2020100318/gfs_z850_vort_us_26.png
https://www.nhc.noaa.gov/xgtwo/two_atl_5d0.png
https://uploads.disquscdn.com/images/f91394dff862ab7bcadc3da6eefef48a7831f0c0ad01d2657316f3364acd9410.gif?w=600&h=348
http://www.weather.gov/images/tbw/graphicast/image3.png?3f5ee345fdf565bc28043b6698bdaaf2
But this isn’t the other blog so why keep bringing it up?
What are your requirements for a season to be a bust?
Seems to be a stormy start to october huh
https://www.nhc.noaa.gov/xgtwo/two_atl_2d0.png
GOM loop…
https://cdn.star.nesdis.noaa.gov/GOES16/ABI/SECTOR/GM/GEOCOLOR/GOES16-GM-GEOCOLOR-1000×1000.gif?hash=42323
Atlantic basin….
https://cdn.star.nesdis.noaa.gov/GOES16/ABI/SECTOR/TAW/GEOCOLOR/GOES16-TAW-GEOCOLOR-900×540.gif?hash=29160
SST’s last 30 days….notice how Paulette and Teddy churned up cooler waters on the way towards Bermuda…..
https://coralreefwatch.noaa.gov/data/5km/v3.1/current/animation/gif/sst_animation_30day_crb_930x580.gif
Thanks for another great update, Dr. Masters! Have a good Saturday!
Thank you Dr. Masters.
With that tenuous, weird and wandering post-Yucatan path projection for Gamma, still hard to be certain of much about it, other than the likely weakening. If it does steer further west, given saturation from Laura and Beta, not good for central Gulf Coast.
Tropical Storm Gamma Tropical Cyclone Update
NWS National Hurricane Center Miami FL AL252020
1200 PM CDT Sat Oct 03 2020
…GAMMA MAKES LANDFALL NEAR TULUM, MEXICO…
Surface observations and satellite images indicate that the center
of Tropical Storm Gamma made landfall in the northeast Yucatan
Peninsula near Tulum, Mexico, around 1145 AM CDT. The storm was
very close to hurricane strength at landfall, with maximum
sustained winds near 70 MPH (110 MPH) with higher gusts.
A weather station at Xel-Ha Park, along the Yucatan coast just
north of Tulum, reported a sustained wind of 55 mph (89 km/h) and a
gust to 68 mph (109 km/h) within the past hour.
SUMMARY OF 1200 PM CDT…1700 UTC…INFORMATION
—————————————————
LOCATION…20.2N 87.5W
ABOUT 0 MI…0 KM N OF TULUM MEXICO
MAXIMUM SUSTAINED WINDS…70 MPH…110 KM/H
PRESENT MOVEMENT…NW OR 315 DEGREES AT 9 MPH…15 KM/H
MINIMUM CENTRAL PRESSURE…980 MB…28.94 INCHES
$$
Forecaster Pasch
https://www.nhc.noaa.gov/storm_graphics/AT25/refresh/AL252020_3day_most_likely_toa_no_wsp_34+png/150003_most_likely_toa_no_wsp_34.png