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Atlantic Tropical Weather Discussion



000
AXNT20 KNHC 201753
TWDAT 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1805 UTC Mon Sep 20 2021

Tropical Weather Discussion for North America, Central America
Gulf of Mexico, Caribbean Sea, northern sections of South
America, and Atlantic Ocean to the African coast from the
Equator to 31N. The following information is based on satellite
imagery, weather observations, radar and meteorological analysis.

Based on 1200 UTC surface analysis and satellite imagery through
1720 UTC.

...SPECIAL FEATURES...

The center of Tropical Storm PETER, at 20/1500 UTC, is near 
19.5N 60.9W. Peter is moving toward the west-northwest, or 290 
degrees, 13 knots. The estimated minimum central pressure is 
1007 mb. The maximum sustained wind speeds are 45 knots with 
gusts to 55 knots. Precipitation: scattered to numerous strong 
in clusters is within 210 nm of the center in the NE semicircle. 
Widely scattered moderate to isolated strong is elsewhere, from 
T.S. Peter and the Greater Antilles to the 31N58W-to-29N69W cold 
front, between 54W and 70W. Please, read the latest NHC Public 
Advisory at:
https://www.nhc.noaa.gov/text/MIATCPAT1.shtml, and the 
Forecast/Advisory at: 
https://www.nhc.noaa.gov/text/MIATCMAT1.shtml, for more details.

The center of Tropical Storm ROSE, at 20/1500 UTC, is near 17.3N 
33.4W. Rose is moving toward the northwest, or 320 degrees, 14 
knots. The estimated minimum central pressure is 1007 mb. The 
maximum sustained wind speeds are 35 knots with gusts to 45 
knots. Precipitation: numerous strong is within 135 nm of the 
center in the western quadrant. Isolated moderate is elsewhere 
within 660 nm of the center in the northern semicircle. Please, 
read the latest NHC Public Advisory at:
https://www.nhc.noaa.gov/text/MIATCPAT2.shtml, and the 
Forecast/Advisory at: 
https://www.nhc.noaa.gov/text/MIATCMAT2.shtml, for more details.

...TROPICAL WAVES...

An Atlantic Ocean tropical wave is along 20W/21W, from 19N 
southward, moving westward 10 to 15 knots. A 1009 mb low 
pressure center is along the tropical wave, near 09.5N. The 
precipitation pattern is showing some signs of organization. 
Upper level winds are expected to become more conducive for 
further development by the middle of the week. A tropical 
depression is likely to form by Friday, while the system moves 
westward 10 to 15 mph, through the eastern and central sections 
of the tropical Atlantic Ocean. Precipitation: widely scattered 
moderate to isolated strong is within 360 nm of the center in 
the NW quadrant. Please, refer to the Tropical Weather Outlook, 
at www.nhc.noaa.gov/gtwo.php?basin=atlc&fdays=2, for more 
details.

...MONSOON TROUGH/ITCZ...

The monsoon trough passes through the coastal plains of 
Guinea-Bissau near 12N16W, to the 1009 mb low pressure center 
that is along the 20W/21W tropical wave, to 07N30W and 07N38W. 
The ITCZ continues from 07N38W to 08N42W, and to the coastal 
plains of NE French Guiana. Precipitation: widely scattered 
moderate to isolated strong is from 02N to 07N between 50W and 
56W, mostly inland in parts of Brazil, French Guiana, and 
Suriname, and elsewhere in the coastal waters of those 
countries. 

GULF OF MEXICO...

A surface trough extends from the Florida Panhandle to the 
eastern sections of Texas. Precipitation: widely scattered 
moderate to isolated strong is within 180 nm of the coast of the 
U.S.A. from 90W eastward. Isolated moderate is within 180 nm of 
the coast of the U.S.A. and Mexico, from 23N northward from 90W 
westward. 

Weak high pressure will extend across the eastern and central 
Gulf of Mexico through Tue. This pattern will support continued 
gentle to moderate winds and mostly slight seas across the Gulf. 
An early season cold front is expected to enter the NW Gulf 
early Wed and reach from the NE Gulf to
central Bay of Campeche by late Thu.

CARIBBEAN SEA...

An upper level trough passes through the SE Bahamas near 22N73W, 
across SE Cuba, to the central coast of eastern Nicaragua. 
Precipitation: isolated moderate to locally strong is to the 
north of the line that runs from 15N70W to the central coast of 
eastern Nicaragua. 

The eastern extension of the eastern Pacific Ocean monsoon 
trough is along 09N/10N, between 74W in Colombia, beyond 
southern Costa Rica, and into the eastern Pacific Ocean. 
Precipitation: scattered to numerous strong in individual 
clusters is within 60 nm on either side of the monsoon trough in 
the SW corner of the Caribbean Sea. 

Tropical Storm Peter is northeast of the Leeward Islands near 
19.5N 60.9W 1007 mb at 1500 UTC moving WNW at 13 kt. Maximum 
sustained winds are 45 kt with gusts to 55 kt. Peter will 
continue to move WNW and reach near 20.8N 64.8W Tue morning, 
then begin to turn more NW and slowly weaken, reaching near 
22.7N 67.9W Wed morning, then weaken to a tropical depression as 
it continues to move northward toward Bermuda through the rest 
of the week. As this occurs, trade winds over the south-central 
Caribbean will diminish through Thu night. Look for associated 
showers and thunderstorms to affect the NE Caribbean and 
adjacent waters through tonight.

ATLANTIC OCEAN...

Information about Tropical Storm Peter, and about Tropical Storm 
Rose, is given in the SPECIAL FEATURES section, .

A cold front passes through 31N58W to 29N69W. A stationary front 
continues from 29N69W, northwestward, beyond NE Florida/SE 
Georgia. An upper level cyclonic circulation center is about
420 nm to the northwest of T.S. Peter. Precipitation: scattered 
to numerous strong is from 29N to 32N between 77W and 80W. 
Widely scattered moderate to isolated strong is elsewhere within 
120 nm on either side of the frontal boundary, and from Cuba to 
28N between 75W and Florida. Widely scattered moderate to 
isolated strong also covers the waters that are from T.S. Peter 
and the Greater Antilles to the 31N58W-to-29N69W cold front, 
between 54W and 70W.

The Cumbre Vieja volcano, that is on the island of La Palma in 
the Canary Islands, has been erupting since 19/1410 UTC. Marine 
and aviation interests should monitor this on-going situation by 
reading the Volcanic Ash Advisory, that is issued by Meteo-
France, at http://vaac.meteo.fr/volcanoes/la-palma/.

Tropical Storm Peter is northeast of the Leeward Islands near 
19.5N 60.9W 1007 mb at 1500 UTC moving WNW at 13 kt. Maximum 
sustained winds are 45 kt with gusts to 55 kt. Peter will 
continue to move WNW and reach near 20.8N 64.8W Tue morning, 
then begin to turn more NW and slowly weaken, reaching near 
22.7N 67.9W Wed morning. Peter will weaken to a tropical 
depression near 23.5N 68.6W Wed evening, then move to 24.5N 
68.7W by Thu morning. Peter will change little in intensity as 
it moves northward toward Bermuda throughout the rest of the 
week. Elsewhere west of 70W, gentle to moderate winds and slight 
to moderate seas will persist over open waters through the early 
part of the week, with swell to 8 ft associated with the 
tropical storm reaching the waters east of 72W by Wed. 

$$
MT