Tropical Discussion

272
axnt20 knhc 261748
twdat

Tropical weather discussion
NWS TPC/National Hurricane Center Miami FL
105 PM EST Thu Nov 26 2009

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...meteorological analysis...weather
observations...and radar.

Based on 1200 UTC surface analysis and satellite imagery through
1715 UTC.

...ITCZ...

The ITCZ axis is centered along 9n13w 5n30w 4n52w. Clusters of
widely scattered moderate convection are from 4n-13n between
23w-42w. Most of this activity is the result of W-SW upper level
flow across the tropical Atlc near the base of an upper level trough
with axis from 25n30w SW to 10n55w that is providing an upper level
diffluent environment E of 42w.

...Discussion...

Gulf of Mexico...
as of 1500 UTC...a stationary front crosses the Florida Peninsula
from near Delray Beach to south of Naples and into the se Gulf along
26n82w 24n85w then into the NW Caribbean through the Yucatan
Channel. A pre-frontal surface trough is also analyzed from the W
Atlc over the Florida Straits to western Cuba near 23n83w. Scattered
showers and isolated tstms are within 60/90 nm east of the front
with isolated showers lingering behind the front over the se Gulf S
of 26n E of 87w. Across the remainder of the Gulf...upper level
westerly flow is noted on water vapor imagery as a surface ridge
extends from central Texas along the se Texas and eastern Mexico
Gulf Coast to the Yucatan Peninsula. Northerly winds up to 25 kt are
forecast through late Friday as high pressure continues to build
into the N/central Gulf by early Saturday.

Caribbean Sea...
a stationary front extends from the se Gulf of Mexico through the
Yucatan Channel to the southern Belize coast near 16n88w. Low-level
convergence in the vicinity of the frontal boundary is generating
scattered showers from 15n-20n between 85w-89w. Farther se...low-
level convergence of easterly tradewinds is producing scattered
showers and isolated tstms within 60 nm either side of a line from
9n76w to 14n84w. This activity is continuing to be enhanced by an
upper level anticyclonic circulation centered over the SW Caribbean
near 13n79w providing an upper diffluent environment across the
western Caribbean. East of the ridge axis along 79w...the remainder
of the Caribbean Sea is under the influence of dry and stable upper
level nwly flow. This is providing strong subsidence and overall
fair skies E of 78w. However...a few isolated low-level showers are
occurring N of 16n between 64w-70w...including Puerto Rico...the
Mona Passage...and eastern Hispaniola.

Atlantic Ocean...
an upper level trough is located over the eastern conus with an
embedded upper level shortwave trough near Cape Hatteras North
Carolina. This shortwave supports a 1009 mb surface low centered
near 31n75w with a stationary front extending SW to near Delray
Beach Florida. A pre-frontal trough is analyzed from the low S-SW
across the NW Bahamas to The Straits of Florida near 24n80w.
Isolated showers are within 120 nm either side of the stationary
front across the Florida Peninsula and nearby coastal waters with
scattered showers occurring within 30 nm of the surface trough
across the Bahamas and Straits of Florida. The upper level trough
axis extends from North Carolina into the W Atlc along 74w. East of
this axis...upper level diffluence is generating scattered showers N
of 24n between 65w-74w. Farther east across the central Atlc...an
upper level low is centered near 29n54w and supports a dissipating
1015 mb surface low near 31n58w. Se of the surface low...a surface
trough is analyzed from 31n54w to 26n52w to 22n56w. Low-level
convergence near and east of the surface trough coupled with upper
level diffluence E of the upper level trough axis is generating
scattered showers and tstms from 21n-32n between 47w-53w. Overall
surface sely winds continue to feed into this area in the central
Atlc from the tropics focused near a surface trough that extends
from 10n50w to 19n46w. Scattered showers and tstms are from 11n-23n
between 42w-50w. The remainder of the eastern Atlc is under the
influence of a surface ridge anchored on 1026 mb high centered near
30n24w.

$$
Huffman