TS Melissa

[hawkeye_wx]

12z Euro is similar to past runs.... stays relatively weak and is able to not get pulled north early, then blows up south of Jamaica and is quickly yanked north by the next trough.

[Amped]

Surprised to see no models caving in yet.  Gfs clearly shows too much intensification given the amount of shear, even if it's track ends up correct.

Euro and Icon seem to have the middle of the road tracks where it stalls near Jamaica thats my current leaning.

Cmc and Ukmet have a west bias, so they are the least likely Imo.

Edit: The 12z eps has a lot of members with strong lows near the Honduras coast so maybe that solution has a better chance than I originally thought.

 

 

[GaWx]

1. 12Z UKMET (goes to 168) maps once again have the low stay in the S Car and go west into Nicaragua; low is a bit stronger with it down to 1003 at strongest, which should easily be strong enough to be a TD although the textual output doesn’t show that.

Will UK for 98L be a miserable fail, the big winner, or in between? Stay tuned!

 

2. 12Z JMA (goes to 192): has a cat 1 hurricane headed due west to just offshore the Nicaragua/Honduras border

[GaWx]

0Z runs: all are now out

-Icon cat 2 H W. Haiti

-CMC first moves W and then WNW/NW to Jamaica as a TS followed by SW and then abrupt turn to N and then NNE/NE over C Cuba/NC Bahamas as a cat 3 H followed by a turn back to the N with it ending on a heading toward Cape Cod as it gets caught on the E side of a strong trough/upper low

-GFS very consistently hits Hispaniola again (cat 2 H)

-Euro just W of Jamaica, EC Cuba to C Bahamas (MH)

-UKMET remains quite consistent with the track and this time the text has it as a TC through hour 156, after which it weakens on approach to the NE Nicaraguan coast. The direction of movement starts off mainly WNW (with the furthest N being at 15.3N, which is actually furthest N of recent runs) followed by W and then WSW; strongest it gets is a minimal TS and lowest SLP 1004. At hour 156, the 0Z UKMET is a whopping 1,500 miles WSW of the 0Z GFS!

TROPICAL STORM 98L ANALYSED POSITION : 11.1N 69.0W

ATCF IDENTIFIER : AL982025

LEAD CENTRAL MAXIMUM WIND
VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS)
-------------- ---- -------- ------------- -------------
0000UTC 21.10.2025 0 11.1N 69.0W 1009 30
1200UTC 21.10.2025 12 14.0N 71.5W 1008 35
0000UTC 22.10.2025 24 14.0N 73.6W 1006 31
1200UTC 22.10.2025 36 14.2N 74.3W 1005 34
0000UTC 23.10.2025 48 15.3N 75.2W 1004 31
1200UTC 23.10.2025 60 15.3N 75.8W 1005 33
0000UTC 24.10.2025 72 15.3N 76.8W 1005 28
1200UTC 24.10.2025 84 15.3N 77.3W 1005 27
0000UTC 25.10.2025 96 14.7N 78.0W 1005 25
1200UTC 25.10.2025 108 14.6N 79.1W 1006 26
0000UTC 26.10.2025 120 14.2N 80.6W 1004 23
1200UTC 26.10.2025 132 14.4N 81.8W 1005 25
0000UTC 27.10.2025 144 13.9N 82.5W 1004 20
1200UTC 27.10.2025 156 14.1N 82.8W 1005 18
0000UTC 28.10.2025 168 CEASED TRACKING

[GaWx]

1. 6Z Euro 144: significant shift NE vs 0Z 150 and 12Z 162 (which were both 150-200 miles SSW to SW of Jamaica) with the 6Z 40 miles E of Jamaica. That’s a 200-250 mile NE shift from the 0Z/12Z!

 

2. Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 AM EDT Tue Oct 21 2025

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

1. Caribbean Sea (AL98):
Satellite, radar, and surface observations indicate that the area 
of low pressure over the central Caribbean Sea appears to be 
developing a well-defined center, and is already producing winds up 
to 45 mph.  A tropical storm is expected to form later today while 
it slows down over the central Caribbean Sea.   Heavy rainfall and 
gusty winds are possible over portions of the ABC Islands during the 
next day or two.  Interests in Puerto Rico, Hispaniola, Jamaica, and 
Cuba should monitor the progress of this system as there is a risk 
of heavy rain and flooding, strong winds, and rough surf later this 
week.  The Air Force Hurricane Hunters are scheduled to investigate 
the system later today.  For additional information on this system, 
including Gale Warnings, please see High Seas Forecasts issued by 
the National Weather Service. 
* Formation chance through 48 hours...high...near 100 percent.
* Formation chance through 7 days...high...near 100 percent.



High Seas Forecasts issued by the National Weather Service
can be found under AWIPS header NFDHSFAT1, WMO header FZNT01 
KWBC, and online at ocean.weather.gov/shtml/NFDHSFAT1.php


Forecaster Cangialosi

[GaWx]

 Whereas the 6Z Euro shifted 200-250 miles NE of the 0Z/12Z runs for that forecast time, keep in mind that the 6Z Euro op is near the NE most 6Z EPS members:

6Z Euro op 144: 40 miles E of easternmost point of Jamaica

 

6Z EPS 144: large majority are 300-500 miles WSW to SW of the Euro op!

[GaWx]

The 12Z position is estimated to be near 14.3N, 71.3W, per this:

AL, 98, 2025102112, , BEST, 0, 143N, 713W, 45, 1003, LO

Thus we now know with more confidence that the 6Z GFS’ 6 hour position near 14.3N, 70.4W is ~60 miles too far east.

 It’s likely going to be designated as TS Melissa at 11AM per this:

```AL, 13, 2025102112, , BEST, 0, 143N, 713W, 45, 1003, TS, 34, NEQ, 100, 70, 0, 40, 1009, 150, 35, 55, 0, L, 0, , 0, 0, MELISSA, M, 0, , 0, 0, 0, 0, genesis-num, 035, TRANSITIONED, alB82025 to al132025,```

 Melissa’s center is on the W edge of the convection meaning nearly half naked as has been expected initially while the shear is strong.

[WxWatcher007]

11 hours too late for my forecast but them’s the breaks.

[GaWx]

Tropical Storm Melissa Discussion Number 1
NWS National Hurricane Center Miami FL AL132025
1100 AM EDT Tue Oct 21 2025

Satellite images, regional Caribbean radar data, and surface
observations indicate that invest 98L has developed a well-defined
center and organized deep convection to be designated a tropical
cyclone. A ship report that recently passed near the center of the
system reported a minimum pressure of about 1003 mb. Satellite
imagery shows the system is asymmetric, with the low-level center
near the western edge of the central dense overcast. The initial
intensity is set at 45 kt, based on a blend of the latest satellite
intensity estimates, marking the formation of Tropical Storm
Melissa. An Air Force Hurricane Hunter aircraft is scheduled to
investigate the system this afternoon, and their data should provide
a better assessment of Melissa's strength and structure.

The system was moving very quickly westward over the past several
days, but it has slowed down significantly this morning, which has
likely helped Melissa form. The initial motion is estimated to be
280/12 kt. Melissa should continue to slow down and gradually turn
to the northwest and then north during the next couple of days
toward a weakness in the subtropical ridge. This motion will likely
take the storm very near the southwestern tip of Haiti and Jamaica
by Thursday. After that time, the guidance diverges significantly
with some models like the GFS and HWRF showing a motion to the
northeast into the weakness, while the other solutions show a stall
or a westward drift on the south side of a building ridge. An
examination of the GFS, ECMWF, and Google DeepMind ensemble suites
suggest that the majority of the members show Melissa not moving
into the weakness and remaining in the Caribbean Sea throughout the
week and into the weekend. The NHC official track forecast lies
between the Google DeepMind ensemble mean track and the correct
consensus aid, HCCA.

Melissa is expected to be over the very warm waters of the
Caribbean, but the models suggest that vertical wind shear will be
moderate with some dry air in the vicinity of the storm during the
next few days. Based on these mixed signals, the strengthening
trend is expected to be slow and steady, not rapid. However, the
future intensity of Melissa is linked to the track and since that is
quite uncertain beyond a couple of days, the strength of the storm
is also quite uncertain. The NHC intensity forecast is in best
agreement with the HCCA model.

Key Messages:

1. Melissa is expected to bring heavy rainfall and the risk of
significant flash flooding and the danger of landslides to portions
of Haiti and the Dominican Republic through the weekend.

2. A Hurricane Watch has been issued for the southern coast and
Tiburon peninsula of Haiti. A Tropical Storm Watch has been issued
for Jamaica. Preparations to protect life and property should be
completed by Thursday.

3. There is significant uncertainty in the track and intensity
forecast of Melissa. Interests elsewhere in Hispaniola and Cuba
should continue to monitor the latest forecasts.


FORECAST POSITIONS AND MAX WINDS

INIT 21/1500Z 14.3N 71.7W 45 KT 50 MPH
12H 22/0000Z 14.4N 72.8W 50 KT 60 MPH
24H 22/1200Z 14.8N 73.5W 55 KT 65 MPH
36H 23/0000Z 15.3N 74.2W 60 KT 70 MPH
48H 23/1200Z 15.7N 74.5W 60 KT 70 MPH
60H 24/0000Z 16.1N 74.6W 60 KT 70 MPH
72H 24/1200Z 16.5N 74.5W 60 KT 70 MPH
96H 25/1200Z 16.9N 74.5W 65 KT 75 MPH
120H 26/1200Z 17.2N 74.9W 70 KT 80 MPH

$$
Forecaster Cangialosi/Bucci

[hawkeye_wx]

The surface center is leaving the convection behind again this morning.

[Floydbuster]

 

[Amped]

1 hour ago, hawkeye_wx said:

The surface center is leaving the convection behind again this morning.

Yeah it does not look like it's going to strengthen much in the near term.

[GaWx]

12Z 

-GFS (Hisp.), CMC (C Cuba), Icon (weaker than recent runs but still E of Jamaica to Jamaica) and UKMET (Nic/Honduras border) are pretty similar to recent runs.

UK:

TROPICAL STORM MELISSA    ANALYSED POSITION : 14.7N  70.8W

     ATCF IDENTIFIER : AL132025

                        LEAD                 CENTRAL     MAXIMUM WIND
      VERIFYING TIME    TIME   POSITION   PRESSURE (MB)  SPEED (KNOTS)
      --------------    ----   --------   -------------  -------------
    1200UTC 21.10.2025    0  14.7N  70.8W     1007            36
    0000UTC 22.10.2025   12  14.7N  73.1W     1005            33
    1200UTC 22.10.2025   24  15.0N  74.3W     1005            36
    0000UTC 23.10.2025   36  15.5N  75.0W     1004            35
    1200UTC 23.10.2025   48  16.1N  76.4W     1005            35
    0000UTC 24.10.2025   60  16.4N  76.4W     1005            27
    1200UTC 24.10.2025   72  16.6N  76.7W     1005            30
    0000UTC 25.10.2025   84  16.4N  78.0W     1005            27
    1200UTC 25.10.2025   96  15.7N  79.7W     1006            25
    0000UTC 26.10.2025  108  15.1N  81.5W     1005            23
    1200UTC 26.10.2025  120  15.0N  82.8W     1005            24
    0000UTC 27.10.2025  132  15.5N  84.0W     1006            22
    1200UTC 27.10.2025  144              CEASED TRACKING

[hawkeye_wx]

The new Euro is more like its ensembles.  It tracks a bit farther sw over the next couple days, which then allows it to get caught under the ridge and turned toward the wsw.  It also blows up south of Jamaica.

[Amped]

Recon not really finding a closed center. Clearly a low level circulation on the visible though at around 14.2N 72.8W and still zipping west. This would rule out the GFS solution if it keeps up for a few hours.

[hawkeye_wx]

12z Euro

[hawkeye_wx]

14 minutes ago, Amped said:

Recon not really finding a closed center. Clearly a low level circulation on the visible though at around 14.2N 72.8W and still zipping west. This would rule out the GFS solution if it keeps up for a few hours.

This is a very weak system.  As you say, if it's even closed it's just barely.  All of the convection was lost this morning, so it may even be weakening.  It will likely have another nice convective blow-up just east of the center tonight.

[Interstate]

If the Euro is right... Jamaica would be no more.

[GaWx]

BULLETIN
Tropical Storm Melissa Advisory Number 2
NWS National Hurricane Center Miami FL AL132025
500 PM EDT Tue Oct 21 2025

...HEAVY RAINS EXPECTED TO SPREAD OVER HISPANIOLA DURING THE
NEXT COUPLE OF DAYS...


SUMMARY OF 500 PM EDT...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...14.2N 73.0W
ABOUT 305 MI...495 KM S OF PORT AU PRINCE HAITI
MAXIMUM SUSTAINED WINDS...50 MPH...85 KM/H
PRESENT MOVEMENT...W OR 275 DEGREES AT 15 MPH...24 KM/H
MINIMUM CENTRAL PRESSURE...1003 MB...29.62 INCHES





Tropical Storm Melissa Discussion Number 2
NWS National Hurricane Center Miami FL AL132025
500 PM EDT Tue Oct 21 2025

Satellite data indicate that Melissa is struggling in strong shear,
which has been the theme for many systems over the deep tropics this
year. The low-level center of the storm is exposed to the west of
the main area of thunderstorms. Air Force Hurricane Hunters have
been investigating the system this afternoon and found that the
minimum pressure is around 1003 mb. Based on their observations,
ASCAT passes, and Dvorak estimates, the initial intensity is held at
45 kt. Melissa's wind field is also quite asymmetric, with most of
the tropical-storm-force winds occurring on the system's east side.
Some of the outermost northern bands are approaching Hispaniola, and
these heavy rains are expected to spread across that island during
the next couple of days.

Melissa is a little south of the previous track and it continues to
move westward at about 13 kt. There has been no change to the track
forecast scenario, which remains complicated. Over the next couple
of days, there is fair confidence that Melissa should slow down and
gradually turn to the northwest or north and approach Haiti and
Jamaica late this week. The motion after that appears to be linked
to how strong and vertically aligned the system gets, and
that is when the models diverge. If Melissa organizes like the GFS
predicts, it could turn northeastward into the weakness in the
ridge and move over Hispaniola. Conversely, if Melissa remains
sheared and lopsided, it will likely stall and eventually drift
westward as a ridge builds north of it. Given the expected
continued shear, the NHC track forecast leans toward the latter
scenario. This prediction is a little left of the previous forecast
and remains a blend of the latest Google DeepMind ensemble mean,
the corrected consensus aid HCCA, and simple consensus TVCA.

Although the ocean is very warm, the models suggest that the
vertical wind shear could persist over Melissa during the next few
days. In addition, there is also some dry air in the storm's
vicinity. Based on these mixed signals, the strengthening trend is
expected to be slow. In fact, the new guidance supports nudging the
short term intensity down a bit. If Melissa remains over the
Caribbean late this week and over the weekend, the upper-level winds
could become more conducive for more significant strengthening.
The NHC intensity forecast is in best agreement with the HCCA model.
 

FORECAST POSITIONS AND MAX WINDS

INIT 21/2100Z 14.2N 73.0W 45 KT 50 MPH
12H 22/0600Z 14.5N 73.7W 45 KT 50 MPH
24H 22/1800Z 15.0N 74.4W 50 KT 60 MPH
36H 23/0600Z 15.5N 75.0W 55 KT 65 MPH
48H 23/1800Z 16.1N 75.1W 60 KT 70 MPH
60H 24/0600Z 16.5N 75.0W 60 KT 70 MPH
72H 24/1800Z 16.9N 75.0W 60 KT 70 MPH
96H 25/1800Z 17.3N 75.0W 65 KT 75 MPH
120H 26/1800Z 17.5N 75.2W 75 KT 85 MPH

$$
Forecaster Cangialosi

[SI Mailman]

2 hours ago, Interstate said:

If the Euro is right... Jamaica would be no more.

I'm supposed to be in Jamaica 3 weeks from today as a stop on my cruise, so I'm monitoring this storm closely.  Figures this one is named after my crazy ex.  

[hawkeye_wx]

The surface center continues to track sw of the NHC forecast.

[Floydbuster]

This is a very complicated forecast, I feel for the NHC.