Tropical Weather Discussion
Issued by NWS
AXNT20 KNHC 191806
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
205 PM EDT Sun Mar 19 2017
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
A cold front that moved over the far northwest portion of the
Atlantic this morning has reached a position from near 32N72W to
the NW Bahamas and to South Florida early this afternoon, from
near 32N68W to 28N73W to near 26N80W this evening and from near
32N62W to 26N67W to 23N79W by early on Monday, and from near
32N57W to near 24N60W and stationary to eastern Cuba. Strong
high pressure will build in behind the front through tonight,
with the resultant tight gradient leading to near gale to
minimal gale force northwest winds north of 30N between 71W and
74W. The near gale force to minimal gale force are forecast to
last into early Monday. Strong to near gale force winds
northwest winds are expected elsewhere northwest of the front
through Monday morning before lifting northeast of the area
The Monsoon Trough axis extends from the African coast near
06N10W to 02N14W to 01S30W. The Intertropical Convergence Zone
axis extends from 01S30W to the South American coast near
02S44W. Scattered moderate to isolated strong convection is from
00N-04N between 00W-06W. Isolated moderate convection is within
90 nm either side of the axis between 11W-25W.
GULF OF MEXICO...
As of 1500 UTC, a 1027 mb high is centered over the NW Gulf near
27N92W 1027 mb, with a ridge southeast to the southeast gulf.
The western portion of a cold extends across central Florida
from near Tampa Bay west to 28N85W, and northwest to southeast
Louisiana where it becomes stationary northwest to the north of
the area. 15-20 kt anticyclonic surface flow is over the Gulf
with lightest winds near the high and strongest winds over the
northeast waters in the wake of the front. Latest satellite
imagery shows scattered to locally broken low clouds south of
27N between 84W and 88W, and between 88W and 93W. Scattered low
clouds are over the southwest gulf and lower Straits of Florida.
Isolated showers are possible over the far south-central gulf.
Broken to overcast stratus clouds are noted over southeastern
Louisiana where observations are reporting visibilities in the
range 5-10 nm. Strong subsidence aloft with the surface high
pressure is keeping clear skies elsewhere. The surface high
pressure is forecast to remain nearly stationary over the next
24 hours, then gradually shift eastward through Wednesday. The
cold front will quickly sweep across the remainder of the
eastern gulf through tonight.
A quasi-stationary front extends from eastern Cuba near 21N76W
southwest to far northeast Honduras near 15N83W. Scattered
showers are within 120 nm of the front, except for scattered
showers and isolated thunderstorms noted within 60 to 90 nm
northwest of the front west of 82W. 10-15 kt northeast surface
winds are present to the northwest of the front, while south of
15N west of 72W trade winds are 15-20 kt Northeast to east 10-15
kt trade winds are present across the remainder of the sea.
Satellite imagery shows patches of broken to scattered low
clouds over much of the western Caribbean south of 20N and west
of the frontal boundary. Isolated showers are possible with some
of these clouds. Similar clouds with possible isolated showers
are moving westward over much of the central part of the sea,
and over portions of the sea including over the waters adjacent
to the Leeward and Windward Islands. Broken low clouds with
isolated showers are along and just offshore the southern coast
of Haiti. Strong subsidence providing for generally fair
conditions is present elsewhere over the Caribbean. Little
change is expected over the next couple of days.
Scattered to locally broken low clouds with possible isolated
showers are developing over some sections of the interior of the
island with the combination of present low-level moisture
embedded in the tradewinds. This pattern is expected to change
little over the next 48 hours.
As of 1500 UTC, a cold front is over the western Atlantic from
near 32N75W to inland central Florida just south of Cape
Canaveral. A pre-frontal trough extends from near 32N74W to the
northwest Bahamas. A strong upper trough is moving quickly
eastward from near 32N75W to 26N77W. Scattered strong convection
is occurring north of 25N between 59W and 66W. A quasi-
stationary front is over the central Atlantic from 31N49W to
26N60W to 24N70W to E Cuba near 21N76W. Scattered showers are
within 90 nm of the stationary front. A surface ridge axis
extends from 32N31W to southwest to 27N46W. A large upper level
low is centered over the tropical Atlantic near 19N32W. Upper
level diffluence E of this center is producing scattered showers
within 600 nm E of the center. Another upper level low is
centered over the Canary Islands near 30N15W with showers.
For additional information please visit