Issued at 2100 UTC WED SEP 29 2021

000
WTNT25 KNHC 292042
TCMAT5

TROPICAL STORM VICTOR FORECAST/ADVISORY NUMBER

2
NWS NATIONAL HURRICANE CENTER MIAMI FL

AL202021
2100 UTC WED SEP 29 2021

THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT.

TROPICAL STORM CENTER LOCATED NEAR 8.3N 25.5W AT 29/2100Z
POSITION ACCURATE WITHIN 30 NM

PRESENT MOVEMENT TOWARD THE WEST-NORTHWEST OR 290 DEGREES AT 11 KT

ESTIMATED MINIMUM CENTRAL PRESSURE 1005 MB
MAX SUSTAINED WINDS 35 KT WITH GUSTS TO 45 KT.
34 KT....... 50NE

0SE

0SW 40NW.
12 FT SEAS..120NE 90SE

0SW

0NW.
WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL
MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT.

REPEAT...CENTER LOCATED NEAR 8.3N 25.5W AT 29/2100Z
AT 29/1800Z CENTER WAS LOCATED NEAR 8.1N 25.1W

FORECAST VALID 30/0600Z 8.8N 26.9W
MAX WIND 45 KT...GUSTS 55 KT.
34 KT... 60NE 40SE 20SW 50NW.

FORECAST VALID 30/1800Z 9.5N 28.9W
MAX WIND 55 KT...GUSTS 65 KT.
50 KT... 30NE

0SE

0SW

0NW.
34 KT... 90NE 70SE 30SW 60NW.

FORECAST VALID 01/0600Z 10.3N 30.8W
MAX WIND 65 KT...GUSTS 80 KT.
64 KT... 15NE

0SE

0SW

0NW.
50 KT... 30NE 20SE 10SW 30NW.
34 KT...100NE 70SE 40SW 80NW.

FORECAST VALID 01/1800Z 11.4N 32.4W
MAX WIND 70 KT...GUSTS 85 KT.
64 KT... 15NE

0SE

0SW 15NW.
50 KT... 30NE 20SE 20SW 30NW.
34 KT...100NE 70SE 40SW 80NW.

FORECAST VALID 02/0600Z 12.8N 34.1W
MAX WIND 70 KT...GUSTS 85 KT.
50 KT... 30NE 20SE 20SW 30NW.
34 KT...100NE 80SE 40SW 80NW.

FORECAST VALID 02/1800Z 14.7N 35.8W
MAX WIND 60 KT...GUSTS 75 KT.
50 KT... 30NE 20SE

0SW 30NW.
34 KT...100NE 80SE 40SW 80NW.

EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 150 NM
ON DAY 4 AND 175 NM ON DAY 5...AND FOR INTENSITY NEAR 15 KT EACH DAY

OUTLOOK VALID 03/1800Z 19.3N 38.9W
MAX WIND 50 KT...GUSTS 60 KT.

OUTLOOK VALID 04/1800Z 24.9N 40.9W
MAX WIND 40 KT...GUSTS 50 KT.

REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 8.3N 25.5W

NEXT ADVISORY AT 30/0300Z

$$
FORECASTER CANGIALOSI

000

ABNT20 KNHC 291743

TWOAT

Tropical Weather Outlook

NWS National Hurricane Center Miami FL

200 PM EDT Wed Sep 29 2021

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

The National Hurricane Center is issuing advisories on Hurricane

Sam, located several hundred miles east-northeast of the northern

Leeward Islands, and on newly formed Tropical Depression Twenty,

located over the eastern tropical Atlantic.

Showers and thunderstorms remain disorganized in association with a

trough of low pressure located several hundred miles southwest of

the Cabo Verde Islands. Some slow development of this system is

possible during the next couple of days while it drifts

west-northwestward across the central tropical Atlantic.

* Formation chance through 48 hours...low...30 percent.

* Formation chance through 5 days...low...30 percent.

An area of low pressure associated with the remnants of Peter

located several hundred miles south of the coast of Newfoundland

continues to produce disorganized showers and thunderstorms. This

system is moving northeastward over cooler waters and into a region

of very strong upper-level winds, and significant development is

not anticipated. Additional information on this system can be found

in High Seas Forecasts issued by the National Weather Service.

* Formation chance through 48 hours...low...10 percent.

* Formation chance through 5 days...low...10 percent.

&&

Public Advisories on Tropical Depression Twenty are issued under

WMO header WTNT35 KNHC and under AWIPS header MIATCPAT5.

Forecast/Advisories on Tropical Depression Twenty are issued under

WMO header WTNT25 KNHC and under AWIPS header MIATCMAT5.

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

Issued at 1100 AM AST Wed Sep 29 2021

000
WTNT43 KNHC 291441
TCDAT3

Hurricane Sam Discussion Number 28
NWS National Hurricane Center Miami FL

AL182021
1100 AM AST Wed Sep 29 2021

Sam has a well-organized cloud pattern on satellite imagery, with a
90 n mi-wide Central Dense Overcast surrounded by numerous
convective banding features. Upper-level outflow has now become
better established to the southeast of the hurricane. A NOAA
Hurricane Hunter mission from a couple of hours ago reported a 20 n
mi-wide diameter circular eye. The current intensity is held at 115
kt for this advisory, which is a little higher than the maximum
winds observed in the earlier aircraft mission. However, since the
estimated minimum central pressure of 949 is a little lower than it
was earlier this morning and Sam's intensity has been fluctuating,
it is considered prudent not to lower the winds at this time. An
Air Force Hurricane Hunter aircraft is scheduled to investigate the
hurricane soon and will provide another intensity estimate.

Sam continues its slow northwestward trek with the current motion
remaining near 310/8 kt. Sam should move northwestward and then
northward around the western portion of the subtropical ridge over
the eastern Atlantic during the next few days, and turn toward
the north-northeast and northeast later in the forecast period.

The track guidance models are in very good agreement through 72
hours or so, with some increase in model spread thereafter. This
increase in spread is largely due to how Sam will interact with a
strong mid-latitude trough moving through Atlantic Canada. Some
of the guidance suggests that this trough could partially bypass
the hurricane around the end of the period and beyond, but this
is not yet clear. The current NHC forecast track is not much
different from the previous one and is in good agreement with the
dynamical model consensus, TVCA.

The hurricane will continue to move over warm waters and in an
environment of low vertical shear and diffluent upper-level flow
for the next 1-2 days. Thus, it would not be surprising to soon
see some restrengthening. The official intensity forecast is
essentially a blend of the latest Decay-SHIPS and LGEM predictions,
and is very similar to the previous NHC forecast. Sam is likely to
remain a major hurricane into this weekend.

Key Messages:

1. Large swells generated by Sam are affecting the Leeward Islands
and will spread to portions of the Virgin Islands, Puerto Rico,
Hispaniola, the Bahamas, and Bermuda by Thursday or Friday.
Significant swells will likely reach the east coast of the United
States and Atlantic Canada by the weekend. These swells will likely
cause life-threatening surf and rip current conditions, and
beachgoers and other interests along these coasts are urged to
follow the advice of lifeguards and local officials through the
upcoming weekend.

FORECAST POSITIONS AND MAX WINDS

INIT 29/1500Z 19.4N 57.0W 115 KT 130 MPH
12H 30/0000Z 20.3N 58.1W 120 KT 140 MPH
24H 30/1200Z 21.8N 59.6W 120 KT 140 MPH
36H 01/0000Z 23.9N 61.0W 120 KT 140 MPH
48H 01/1200Z 26.6N 61.8W 115 KT 130 MPH
60H 02/0000Z 29.4N 61.8W 110 KT 125 MPH
72H 02/1200Z 32.0N 60.9W 105 KT 120 MPH
96H 03/1200Z 36.2N 57.3W

90 KT 105 MPH
120H 04/1200Z 39.5N 53.0W

75 KT 85 MPH

$$
Forecaster Pasch

5-Day Uncertainty Track last updated Wed, 29 Sep 2021 14:38:28 GMT



Wind Speed Probabilities last updated Wed, 29 Sep 2021 14:38:28 GMT