[Tropical] Tropical Weather Discussion

[EMWIN Server]

AXNT20 KNHC 241755
TWDAT

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1805 UTC Sun Jan 24 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 32N. The following information is based on satellite
imagery, weather observations, radar and meteorological analysis.

Based on 1200 UTC surface analysis and satellite imagery through
1745 UTC.

...SPECIAL FEATURES...

Caribbean Gale Warning: The combination of high pressure located
north of the Caribbean Sea and low pressure over Colombia and
Panama will continue to lead to northeast to east winds to pulse
to gale force within about 90 nm of the coast of Colombia during
the overnight and early morning hours through at least Wed. Wave
heights generated by these winds are forecast to be in the range
of 8-12 ft, mainly around daybreak each day. Please read the
latest NWS High Seas Forecast issued by the National Hurricane
Center at the website
https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml for more details.

...MONSOON TROUGH/ITCZ...

The monsoon trough axis extends from the coast of Liberia near
05N09W to 05N15W, where latest scatterometer data indicates that
it transitions to the ITCZ to 04N25W to 03N36W and to near 01N46W.
Scattered moderate to isolated strong convection is seen within
120 nm north of the ITCZ between 34W-39W. Scattered moderate
convection is within 180 nm south of the monsoon trough between
07W-13Wm, within 120 nm north of the ITCZ between 29W-34W and
within 60 nm north of the ITCZ between 21W-27W.

GULF OF MEXICO...

As of 15Z, a stationary front extends from near Fort Myers,
Florida northwestward to 27N84W, where it becomes a warm front
continuing northwestward to inland far southwestern Mississippi.
Satellite imagery shows patches of low stratus type clouds and
sea fog over the NE Gulf and over the southeastern Gulf from 25N-
28N between 82W-87W. Smaller patches of similar type clouds and
fog are advecting northward over the most of the western Gulf.
Small isolated showers moving northward are over some sections of
the central and western Gulf. Sky conditions are mostly clear
over the far southeastern Gulf south of 25N and over sections of
the south-central Gulf.

As for the forecast: the stationary front will gradually weaken
through this evening as the warm front continues to lift
northward. The area of fog over the NE Gulf will remain through
tonight, while the fog over the southeastern Gulf slowly erodes.
Building high pressure over the southeastern U.S. will bring
increasing southerly return flow and building seas over the
western Gulf during today and through Mon. The ridge will weaken
late Mon as a weak cold front moves into the western Gulf and
becomes stationary by early Tue. The front will then get
reinforced on Wed and progress eastward across the basin into Thu
night. In the wake of this front, gale force north winds are
expected Wed afternoon through Thu over sections of the western
Gulf.

CARIBBEAN SEA...

Pulsing winds to gale force are expected during the overnight and
early morning hours near the coast of Colombia through the next
few days.  Please, refer to the Special Features section above
for details.

Elsewhere, latest ASCAT and buoy data indicate that mainly
moderate to fresh trades are present, with the exceptions of
fresh to strong trades over the southern part of the central
Caribbean near the gale wind area and gentle to moderate trades
over the eastern and northwestern Caribbean. Moderate to fresh
northeast winds are over the Windward Passage. Very stable
atmospheric conditions present throughout, both aloft and at the
low-levels, is allowing for only small patches of rather shallow
moisture in the form of scattered to broken low clouds to exist
across the basin. These clouds are quickly moving westward and
some may be attendant by brief passing isolated showers. Small
patches of low-level clouds with isolated showers that are also
moving quickly westward are near Puerto Rico and the Lesser
Antilles.

As for the forecast: High pressure north of the Caribbean Sea will
continue to allow for the fresh to strong trades over the south-
central Caribbean through at least Wed night. Winds elsewhere will
change little in speeds through Tue night, except winds will pulse
to fresh to strong speeds over the Gulf of Honduras during that
time. North swell will propagate through the Tropical North
Atlantic waters late Mon night through Thu night. A cold front
will approach the Atlantic waters of Puerto Rico and Hispaniola
Mon night. Another cold front will reach the Yucatan Channel late
Thu followed by fresh to strong northerly winds into the weekend.

ATLANTIC OCEAN...

A central Atlantic cold front is analyzed from near 32N46W to
25N59W and to 24N69W, where it transitions to a stationary front
to the NW Bahamas and to South Florida. Broken to overcast low
and mid-level clouds, with patches of rain and possible scattered
showers are along and within 90-120 nm north of the front. A pre-
frontal trough extends from 33N44W to 25N54W. Scattered moderate
to isolated strong convection is within 180 nm east of the trough
north of 28N, while scattered moderate convection is within about
120 nm east of the trough from 25N-28N. This activity is being
enhanced by upper divergence occurring east of a broad upper
trough that reaches from well north of the area southward to near
21N and between 47W-65W. Latest ASCAT data shows fresh to strong
southwest winds east of the pre-frontal to near 42W. Another cold
front is along a position from near 32N54W to 29N61W, where it
begins to weaken to 28N70W. Scattered to broken low clouds, with
possible isolated showers are along and within 60 nm north of the
front east of 61W, while scattered low clouds mark the front west
of 61W. Satellite imagery, quite impressively, shows cold-air
stratocumulus covering the waters north of the second front
between 54W-73W. Latest ASCAT data passes depict strong northwest
to north winds within the area of stratocumulus clouds.

A weak trough extends from 21N52W to 15N54W. Isolated showers are
possible near the trough.

Remnants of old frontal boundaries are presently identified as
weak convergence lines: one extends from 25N50W to the northern
Leeward Islands, and the other one extends from near 24N56W to
21N61W to 20N64W and to the northern part of the Mona Passage and
to inland the east coast of the Dominican Republic. Mostly
scattered low clouds, with possible isolated showers are along and
near these convergence lines.

The remainder of the Atlantic forecast area is under the influence
of a ridge anchored by a high pressure of 1024 mb located just
south of the Madeira Islands near 31N16W. Moderate to fresh winds
are along the southern periphery of the ridge.

As for the forecast: The stationary front will gradually weaken
through this evening, while the cold front that extends from near
32N46W to 25N59W and to 24N69W is overtaken by a reinforcing surge
of high pressure. This will tend to push the front south to along
21N by Sun night and into the Greater Antilles Mon night. Southerly
flow will increase across the waters east of north-central
Florida Mon into Tue. Low pressure near Bermuda will bring strong
west winds to the northeast waters Tue night into Wed. A stronger
cold front will move off the southeastern U.S coast Wed night,
while the associated low pressure rapidly intensifies north of
the area through the end of the week. Gale force winds and very
large seas are expected with this system, mainly to the north of
27N. This could lead to hazardous marine conditions over those
waters.

$$
Aguirre
This weather bulletin was brought to you by:
www.nashvilleweather.net