Good day everyone!
Since “resurrected” FAY and INVEST 90L are far out in the Atlantic and pose no threat to the CONUS or Caribbean islands, this synopsis will focus on the U. S. east coast probable threat.

Regarding the regeneration of FAY…during analysis yesterday, FAY was ingesting dry air, and sitting in a very dry environment. This was noted in WV imagery, and visible imagery with the presence or “arc” clouds. These clouds form near or at the surface when a system takes in dry air, which causes the thunderstorms to collapse, which produce strong downdrafts. These downdrafts when they hit the surface produce these clouds. With forecast analysis, she should have remained dissipated. Did I get this wrong? Not necessarily. The NHC was thinking along the same lines based on 2 of their discussions. First, this is regarding arc clouds: When a tropical system ingests dry air, arc clouds mean the storm is actively choking, destabilizing, and likely weakening. On satellite imagery, these distinct, thin, curved lines of clouds racing away from the storm’s center serve as a visible warning sign that dry air has penetrated the core.

From the NHC SEP 22:
Fay remains mainly comprised of a swirl of low- to mid-level clouds,
although a few isolated patches of convection are occurring in the
eastern semicircle. There has been no organized convection for more
than 18 h, and based on this it appears than Fay has degenerated to
a remnant low pressure area. There is a possibility of convective
bursts occurring during the next few days. However, the cyclone will
be embedded in a dry air mass with strong upper-level convergence,
and these factors should keep organized convection from
re-developing.

SEP 24
Fay is traversing sea surface temperatures around 27-28C in an
environment of low vertical wind shear. However, the system is
embedded within a dry air mass, which should prevent significant
strengthening. In about 24-48 hours, vertical wind shear is forecast
to increase, which should cause the system to gradually weaken and
limit deep convection.

The only thing I can think of, is that FAY somehow became somewhat of a “Marsupial Paradigm” package:
https://met.nps.edu/~mtmontgo/marsupial.html

If anyone has any questions regarding tropical systems, please feel free to email me at the email address at the end of the synopsis. Please title it WEATHER QUESTION.

The following changes have been made. The forecast center is still closed on Sunday, and will be closed on Saturday as well (unless there is a threat from a tropical system). Please refer to the Storm Prediction Center for severe weather information.
SPC LINK
https://www.spc.noaa.gov/

These forecasts can be lengthy, however I want to always give a full perspective on the tropics.
STORM W SEASONAL FORECAST
TOTAL NAMED STORMS: 9 – 11
TOTAL HURRICANES :      3 – 4
MAJOR HURRICANES:      1 – 2

AVERAGE HURRICANE SEASON:
TOTAL NAMED STORMS: 14
TOTAL HURRICANES:         7
MAJOR HURRICANES:       3

2026 SEASON TOTALS
TOTAL NAMED STORMS: 6
TOTAL HURRICANES:       0
MAJOR HURRICANES:     0

The following is the list of storm names for the 2026 Atlantic Hurricane Season. Storm names will be marked in RED for active and already named systems with subtropical systems marked in PURPLE:
Arthur Bertha Cristobal Dolly Edouard Fay Gonzalo Hanna Isaias
Josephine Kyle Leah Marco Nana Omar Paulette Rene Sally Teddy Vicky
Wilfred

Satellite loop imagery indicates about the same as yesterday over the Atlantic, with dry air being the dominant feature.
GOES 19 ATLANTIC IR AND WV SATELLITE LOOP

DEVELOPING EAST COAST SYSTEM, T.S. FAY, AND INVEST 90L SATELLITE LOOP IMAGES



The NHC has increased the development of the INVEST 90L near Africa to a HIGH (70%) probability during the next 7 days. The NHC is issuing advisories on “regenerated” FAY
NHC 7 DAY GTWO (LINKED TO OUTLOOK)

The NHC Surface Analysis indicates the location of Tropical Waves
06Z NHC SURFACE ANALYSIS IMAGE

The following is the ECMWF EPS Cyclone Formation Probabilities forecast during the next 5 days.
ECMWF EPS CYCLONE PROBABILITY 24 – 72 HOURS


72 – 120 HOURS

Analysis this morning of the ECMWF global model indicates development of a closed low off the U.S. east coast early Fri., and eventually becoming more symmetric and consolidated. The area is currently associated with a trough of low pressure currently attached to a stationary frontal boundary off the NC/SC offshore area. Analysis of TPW (surface moisture), relative humidity values (700 mb – 500 mb), and wind shear forecast indicate limited surface moisture, but ample values of mid level moisture throughout the lifespan, with wind shear forecast to remain over the system. By early Sunday, the shear pattern is forecast to briefly become somewhat more favorable with a reduction in shear and a weak, semi radial flow pattern which may remain for approximately 18 – 24 hours. Based on analysis of the recent thermal diagram, the area has been designated as a shallow warm core, asymmetric low and becoming a symmetric, shallow warm core.

My current thinking with this is, as this hits the warmer waters of the Gulfstream, we could see rapid feedback, and the system should become more symmetric. This will probably remain baroclinic in nature most of the forecast period, however based on analysis of mid level temperature forecasts, reduction in shear, and what appears to be a change in structure near the end of the period, this system could possibly try to transition to subtropical. Another item that points toward this is, as the system gets over the warmer waters, it intensifies, and as it moves out of the Gulfstream into cooler waters, it begins to weaken. Not unlike a tropical system.

Regardless, portions of the coastal NEUS area may experience some localized coastal flooding, minor beach erosion, and possible localized power outages.

The model at the moment indicates forecast sustained surface winds of mid grade tropical storm intensity (45 – 50 mph) with gusts of (60 – 65 mph), and significant wave height along portions of the east coast on the order of around 8 – 10 ft., and 14 – 16+ ft offshore.

I will continue to monitor this for the next 72 – 96 hours
ECMWF MSLP ANOMALIES FORECAST 120 HOURS

EAST COAST MSLP ANOMALIES FORECAST

ECMWF SURFACE WINDS FORECAST ANIMATION

WAVEWATCH SIGNIFICANT WAVE HEIGHT FORECAST

Elsewhere, based on the current forecast of the MJO,and Global Tropical Hazards outlook from the CPC, I cannot rule out possible development in the Gulf during the first week of Oct.
ECMWF EPS MJO PHASE SPACE DIAGRAM FORECAST

GLOBAL TROPICAL HAZARDS OUTLOOK

EXCESSIVE RAINFALL
https://www.wpc.ncep.noaa.gov/qpf/excessive_rainfall_outlook_ero.php

SIGNIFICANT RIVER FLOOD OUTLOOK
https://www.wpc.ncep.noaa.gov/nationalfloodoutlook/index.html

Please click on the following map to access the current statements, advisories and warnings from the NWS. Once you click the map, click on your area of interest.
NWS WATCH / WARNING DISPLAY (LINKED…CLICK MAP, THEN YOUR AREA)
NWS RADAR

RAP RADAR (CLICK IMAGE THEN GO TO LOOP DURATION AND PICK LENGTH OF LOOP, THEN CLICK RADAR SITE)WUNDERGROUND RADAR SUMMARY MAP (CLICK FOR UPDATES)PRECIPITATION TYPE (CLICK TO ACCESS ANIMATION FEATURE)CARIBBEAN RADAR (CLICK IMAGE TO ACCESS ANIMATION)

You may direct any questions to me by contacting me personally, ANYTIME, at: [email protected]

Have a blessed day!

T. F. “STORM” WALSH III
GMCS, USCG (ret)
METEOROLOGIST / HURRICANE SPECIALIST / SEVERE WEATHER SPECIALIST
CoCoRAHS OBSERVER

About West Central Florida Hurricane and Severe Weather Forecast Center

I am a Meteorologist, Hurricane Specialist and Severe Weather Specialist, providing hurricane forecasts during the Atlantic Hurricane Season, severe weather forecasts during and off season, as well as winter weather and coastal storm forecasts. I retired from the U.S. Coast Guard in July of 2001. Meteorology became my passion in high school, and I have continued my educational background in meteorology since 1996, when I undertook the study of Tropical Meteorology. While working toward my degree, I had to unexpectedly withdraw from college due to my oldest sons medical reasons. I do however, meet the educational criteria of the AMS to be recognized as a meteorologist. Studies include, but are not limited to the Navy Aerographers Mate course, Naval METOC meteorology course, Meteorology 2010 Sophomore level course while attending St. Petersburg College, Clearwater, FL., Basic Forecasting course for operational meteorologists from Rapid WX meteorology institute, a four month meteorological internship at FOX 13 News, and extensive research on numerous meteorological topics. I have been forecasting Tropical Weather (Tropical Storms and Hurricanes) since 1996, with my main clients at the time being three different Coast Guard Commands.