GeoColor satellite image of an area of disturbed weather over the western Caribbean (95L) at 11:20 a.m. EDT Friday, October 23, 2020. (Image credit: RAMMB/CIRA/Colorado State University)

An area of disturbed weather over the western Caribbean, designated 95L by the National Hurricane Center on Friday morning, was bringing heavy rains to Cuba, Jamaica, and the Cayman Islands. This system had grown much more organized since Thursday, and it is likely to become Tropical Storm Zeta by early next week. A NOAA Hurricane Hunter aircraft is scheduled to investigate 95L on Saturday afternoon.

Figure 1. Radar image of 95L at 11 a.m. EDT October 23. (Image credit: National Weather Service, Cayman Islands)

Satellite imagery on Friday afternoon showed a steady increase in the intensity and areal coverage of 95L’s heavy thunderstorms, and it appeared to be developing a surface circulation near the Cayman Islands. The system was developing low-level spiral bands, and had excellent upper-level outflow to the north. Conditions favored development, with wind shear a moderate 5-15 knots, sea surface temperatures a very warm 29.5 Celsius (85°F), and a moist atmosphere (a mid-level relative humidity near 75%).

Figure 2. Track forecasts out to seven days for 95L from the 6Z (2 a.m. EDT) Friday, October 23, run of the GFS ensemble model (GEFS). The black line is the mean of the 31 ensemble members; individual ensemble member forecasts are the thin lines, color-coded by the central pressure they predict for 95L. Most of the ensemble members predicted a tropical depression or weak tropical storm would form in the western Caribbean or Gulf of Mexico. (Image credit: Tropical Tidbits)

Forecast for 95L

Steering currents are weak in the western Caribbean, and 95L is expected to move slowly northwest or north at less than 5 mph through Sunday. When 95L pushes north of Cuba, a more rapid motion at 10 mph or higher to the north is likely. There is high uncertainty on where 95L might end up: it could push into the Gulf of Mexico, or wind up over the Bahamas, to the east of Florida.

Conditions are predicted to remain favorable for development through Monday, with wind shear a moderate 10-20 knots, sea surface temperatures a very warm 29.5 Celsius (85°F), and plenty of moisture (a mid-level relative humidity of 70-75%). There was modest support for development of 95L from the Friday morning runs of the GFS and European models and their ensembles, showing 95L could become a tropical depression or weak tropical storm by Sunday in the western Caribbean.

Regardless of whether a tropical cyclone forms, heavy rains of 2-5 inches from this system will affect Cuba, the Bahamas, the Cayman Islands, South Florida, the northeast Yucatan Peninsula, and Jamaica through Monday. In a 2 p.m. EDT Friday tropical weather outlook, NHC gave the system two-day and five-day odds of development of 70%. The next name on the Atlantic list of storms is the sixth letter in the Greek alphabet, Zeta.

Figure 3. GeoColor satellite image of Hurricane Epsilon at 9:10 a.m. EDT Friday, October 23. Smoke from Colorado’s second largest fire on record, the 170,000-acre East Troublesome Fire, was carried by the jet stream to the northeast of Epsilon (upper right of image).

Hurricane Epsilon recurving out to sea

Hurricane Epsilon brushed the island of Bermuda overnight, passing about 190 miles to the east of the island. Winds gusted near tropical storm-force at the Bermuda airport, with a peak wind gust of 38 mph. Rainfall amounts on the island were less than an inch.

At 11 a.m. EDT Friday, Epsilon was a category 1 hurricane with top sustained winds of 85 mph and a central pressure of 968 mb, headed north at 10 mph. A large storm, Epsilon had tropical storm-force winds that extended up to 255 miles to the north of the center, with a wind field that will expand as Epsilon heads to the north. The large wind field is generating large swells, which will be affecting the U.S. East Coast, Atlantic Canada, and the north-facing shores of the Caribbean islands through this weekend.

Also see: How climate change is making hurricanes more dangerous

Moderate wind shear of 10-20 knots will combine with sea surface temperatures (SSTs) along Epsilon’s path that will fall from 25.5 Celsius (78°F) on Friday to 24 Celsius (75°F) on Saturday, likely keeping Epsilon at a steady intensity, or cause a slow weakening. Epsilon is expected to recurve on Saturday to the northeast. On Sunday, it may pass close and bring rains of 1-2 inches and wind gusts near tropical storm-force to the southeastern portion of Newfoundland, Canada.

Epsilon will merge with a trough of low pressure to its north on Sunday and transition to a very powerful extratropical storm. Its central pressure on Tuesday, October 27, when it will be a few hundred miles south of Iceland, could be between 931-941 mb, according to the 0Z Friday runs of the GFS and European models.

Website visitors can comment on “Eye on the Storm” posts (see below). Please read our Comments Policy prior to posting. (See all EOTS posts here. Sign up to receive notices of new postings here.)

Posted on October 23, 2020(1:15pm EDT).

Jeff Masters, Ph.D.

Jeff worked as a hurricane scientist with the NOAA Hurricane Hunters from 1986-1990. After a near-fatal flight into category 5 Hurricane Hugo, he left the Hurricane Hunters to pursue a safer passion -...

26 replies on “Disturbance in the western Caribbean likely to become Tropical Storm Zeta”

  2. A lot going on out there. On the right Epsilon at 957mb, causing waves and rip currents along the seaboard. Over Colorado near Utah the pressure is 1023mb. There is a front draped over the east with storms. The square low over Arizona is at 1010mb. 95L has pulled together some this morning.

  6. ZCZC MIATWOAT ALL
TTAA00 KNHC DDHHMM

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
200 AM EDT Sat Oct 24 2020

For the North Atlantic...Caribbean Sea and the Gulf of Mexico:

The National Hurricane Center is issuing advisories on Hurricane 
Epsilon, located over the west-central Atlantic a couple of hundred 
miles northeast of Bermuda.

1. Satellite and surface observations indicate that a broad area of low 
pressure has redeveloped just south of Grand Cayman Island.  Shower 
and thunderstorm activity continues to increase in organization,  
and environmental conditions are expected to remain conducive for 
further development. A tropical depression will likely form during 
the next day or two while the low drifts toward the northwest or 
north.  The system could move near western Cuba by Sunday and move 
slowly across the southeastern Gulf of Mexico by early next week.  
Interests in western Cuba, the Florida Keys, and southern Florida 
should monitor the progress of this disturbance.  Regardless of 
development, locally heavy rainfall will be possible over portions 
of the Cayman Islands, Jamaica, Cuba, southern Florida, the Florida 
Keys, and the northwestern Bahamas through the weekend and into 
early next week.
* Formation chance through 48 hours...high...80 percent.
* Formation chance through 5 days...high...90 percent.

Forecaster Stewart

  7. well at this early time, Euro and Navy models put the storm into La-new orleans area..while Gfs and Canadian have the storm go into panhandle of Fla…lets wait this out as no model put it to hurricane strength..but lets see what happens as it builds up today,just my opinion ok..nothing official

  8. Japan Meteorological Agency
    Tropical Cyclone Advisory #43 – 15:00 PM JST October 24 2020
    SEVERE TROPICAL STORM SAUDEL (T2017)
    =============================================
    South China Sea

    At 6:00 AM UTC, Severe Tropical Storm Saudel (985 hPa) located at 17.8N 112.6E has 10 minute sustained winds of 55 knots with gusts of 80 knots. The cyclone is reported as moving west slowly.

    Storm Force Winds
    ====================
    30 nm from the center

    Gale Force Winds
    =====================
    180 nm from the center in northwestern quadrant
    150 nm from the center in southeastern quadrant

    Dvorak Intensity: T4.0-

    Forecast and Intensity
    =========================
    24 HRS: 17.5N 108.5E – 45 knots (CAT 1/Tropical Storm) Gulf of Tonkin
    48 HRS: 17.3N 104.4E – Tropical Depression Over land Thailand

    ——————————————————————————-

    Tropical Cyclone Advisory #7 – 15:00 PM JST October 24 2020
    TROPICAL DEPRESSION 21
    =============================================
    Sea East of the Philippines

    At 6:00 AM UTC, Tropical Depression (1004 hPa) located at 13.1N 130.1E has 10 minute sustained winds of 30 knots. The depression is reported as moving northwest at 15 knots.

    Dvorak Intensity: T1.5

    Forecast and Intensity
    =========================
    12 HRS: 13.5N 128.2E – 30 knots Tropical Depression in Sea East of the Philippines
    24 HRS: 13.8N 125.8E – 40 knots (CAT 1/Tropical Storm) Sea East of the Philippines
    48 HRS: 13.6N 120.8E – 50 knots (CAT 2/Severe Tropical Storm) Batangas province area (Luzon/Philippines)
    72 HRS: 14.0N 115.8E – 60 knots (CAT 2/Severe Tropical Storm) South China Sea

  10. India Meteorological Department
    Tropical Cyclone Advisory #11 – 5:30 AM IST October 24 2020
    WELL MARKED LOW PRESSURE AREA BOB03-2020
    =============================================

    At 0:00 AM UTC, The Depression moved north northeastwards, weakened into a well marked low pressure area and lays centered over central Bangladesh & neighborhood.

    As per satellite imagery, the system is over northeastern Bangladesh & neighborhood centered within half a degree of 24.5N 90.5E. Center not clearly defined in infrared imagery. Intense to very intense convection lay over eastern Bangladesh adjoining northeastern Bay of Bengal & northeastern states. Minimum cloud top temperature is -93C.

    3 minute sustained winds near the center is 15 knots with gusts of 25 knots. The estimated central pressure of the well marked low pressure area is 1001 hPa.

    This is the final tropical cyclone advisory on BOB03-2020 from RSMC New Delhi

  11. Tropical Weather Outlook
    NWS National Hurricane Center Miami FL
    800 PM EDT Fri Oct 23 2020

    For the North Atlantic…Caribbean Sea and the Gulf of Mexico:

    The National Hurricane Center is issuing advisories on Hurricane
    Epsilon, located over the west-central Atlantic a couple of hundred
    miles northeast of Bermuda.

    Satellite images and surface observations indicate that the broad
    area of low pressure located just west of Grand Cayman Island
    continues to show signs of organization. Environmental conditions
    appear conducive for further development, and a tropical depression
    will likely form during the next day or two while the low drifts
    toward the northwest. The system could move near western Cuba by
    Sunday and move slowly across the southeastern Gulf of Mexico by
    early next week. Interests in western Cuba, the Florida Keys, and
    southern Florida should monitor the progress of this disturbance.
    Regardless of development, locally heavy rainfall will be possible
    over portions of the Cayman Islands, Jamaica, Cuba, southern
    Florida, the Florida Keys, and the northwestern Bahamas through the
    weekend.
    * Formation chance through 48 hours…high…70 percent.
    * Formation chance through 5 days…high…70 percent.

    $$
    Forecaster Pasch

  13. Japan Meteorological Agency
    Tropical Cyclone Advisory #41 – 9:00 AM JST October 24 2020
    SEVERE TROPICAL STORM SAUDEL (T2017)
    =============================================
    South China Sea

    At 0:00 AM UTC, Severe Tropical Storm Saudel (980 hPa) located at 18.2N 113.3E has 10 minute sustained winds of 60 knots with gusts of 85 knots. The cyclone is reported as moving west northwest slowly.

    Storm Force Winds
    ====================
    40 nm from the center

    Gale Force Winds
    =====================
    180 nm from the center in northwestern quadrant
    120 nm from the center in southeastern quadrant

    Dvorak Intensity: T4.0-

    Forecast and Intensity
    =========================
    24 HRS: 17.6N 109.0E – 50 knots (CAT 2/Severe Tropical Storm) Gulf of Tonkin
    48 HRS: 17.5N 105.2E – Tropical Depression Over land Laos

    —————————————————————————-

    Tropical Cyclone Advisory #5 – 9:00 AM JST October 24 2020
    TROPICAL DEPRESSION 21
    =============================================
    Sea East of the Philippines

    At 0:00 AM UTC, Tropical Depression (1006 hPa) located at 11.8N 131.4E has 10 minute sustained winds of 30 knots. The depression is reported as moving west northwest at 12 knots.

    Dvorak Intensity: T1.5

    Forecast and Intensity
    =========================
    12 HRS: 12.8N 129.6E – 30 knots Tropical Depression in Sea East of the Philippines
    24 HRS: 13.3N 127.5E – 35 knots (CAT 1/Tropical Storm) Sea East of the Philippines
    48 HRS: 13.6N 122.7E – 55 knots (CAT 2/Severe Tropical Storm) Quezon province area (Luzon/Philippines)
    72 HRS: 13.7N 117.8E – 55 knots (CAT 2/Severe Tropical Storm) South China Sea

  15. Imagine that even Levi Cohen’s agrees with me with his new video he just put out . S ridge will. Keep the 95l storm way west of Central Florida and the trough will make it go away east of Florida and other words central Florida no matter how you slice it will get nothing again…. looks like I will go 11 for 11 with my predictions this year… 100% accurate and correct all season long

  19. Japan Meteorological Agency
    Tropical Cyclone Advisory #39 – 3:00 AM JST October 24 2020
    TYPHOON SAUDEL (T2017)
    =============================================
    South China Sea

    At 18:00 PM UTC, Typhoon Saudel (975 hPa) located at 18.0N 113.9E has 10 minute sustained winds of 65 knots with gusts of 95 knots. The cyclone is reported as moving west slowly.

    Storm Force Winds
    ====================
    40 nm from the center

    Gale Force Winds
    =====================
    180 nm from the center in northwestern quadrant
    120 nm from the center in southeastern quadrant

    Dvorak Intensity: T5.0-

    Forecast and Intensity
    =========================
    24 HRS: 17.7N 110.0E – 55 knots (CAT 2/Severe Tropical Storm) South China Sea
    48 HRS: 17.8N 106.6E – 35 knots (CAT 1/Tropical Storm) Gulf of Tonkin
    72 HRS: 17.8N 103.0E – Tropical Depression Over land Thailand

    ————————————————————————————-

    Tropical Cyclone Advisory #3 – 3:00 AM JST October 24 2020
    TROPICAL DEPRESSION 21
    =============================================
    Sea East of the Philippines

    At 18:00 PM UTC, Tropical Depression (1004 hPa) located at 11.3N 132.5E has 10 minute sustained winds of 30 knots. The depression is reported as moving west northwest at 8 knots.

    Dvorak Intensity: T1.5

    Forecast and Intensity
    =========================
    24 HRS: 13.3N 128.9E – 35 knots (CAT 1/Tropical Storm) Sea East of the Philippines
    48 HRS: 13.6N 124.2E – 55 knots (CAT 2/Severe Tropical Storm) Sea East of the Philippines
    72 HRS: 13.7N 119.1E – 55 knots (CAT 2/Severe Tropical Storm) South China Sea

  20. India Meteorological Department
    Tropical Cyclone Advisory #10 – 23:30 PM IST October 23 2020
    DEPRESSION BOB03-2020
    =============================================

    At 18:00 PM UTC, The Depression moved north northeastwards with a speed of 15 km/h during past 6 hours and lay centered over central Bangladesh & neighborhood, near 24.0N 89.9E, about 230 km north northwest of Khepupara (Bangladesh), 50 km west northwest of Dhaka (Bangladesh) and about 140 km west of Agartala (Tripura).

    It is very likely to move further north northeastwards maintaining the intensity of depression for next 6 hours and weaken thereafter into a well marked low pressure area over northern parts of Bangladesh & neighborhood.

  22. Thanks for the update Dr. Jeff. I really hope the GFS is wrong. I liked it better when the NHC had it heading to the east coast of FL/Bahamas.

  23. Thank You for the Update Dr. Masters; we will probably have a better idea of what to expect with potential Zeta by Monday when it gets into the S Gulf or Florida Straits in terms of wind impacts. Looks to bring a nice rain punch regardless but it looks like potential shear will keep the brakes on in terms of a higher-end hurricane event.

Comments are closed.