AXNT20 KNHC 040552
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
120 PM Tue Aug 04 2020
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 0000 UTC surface analysis and satellite imagery through
Doppler radar imagery and surface observations indicate that eye
of Hurricane Isaias made landfall in southern North Carolina
around 1110 PM EDT (0310 UTC) near Ocean Isle Beach, with
maximum sustained winds of 75 kt or 85 mph (140 km/h).
At 04/0300 UTC, Isaias was centered near 33.8N 78.5W or about 22
nm ENE of Myrtle Beach, South Carolina moving NNE at 19 kt. The
estimated minimum central pressure is 988 mb. Maximum sustained
winds are 75 kt with gusts to 90 kt. Scattered to numerous
moderate convection is noted north of 31N between 75W-80W.
Maximum seas expected with this system can reach 26 ft.
On the forecast track, the center of Isaias will move across
eastern North Carolina for the rest of the night. The center
move near or along the coast of the mid-Atlantic states on
Tuesday, and continue across the northeastern United States
Please read the latest NHC Public Advisory at
https://www.nhc.noaa.gov/text/MIATCMAT4.shtml for more details.
A far eastern Atlantic tropical wave has its axis along 21W from
03N-18N, moving westward at 10-15 kt. The majority of this
wave is embedded with deep tropical moisture associated with the
African monsoon trough that extends into the eastern Atlantic.
Scattered moderate convection is noted from 07N-14N between
An eastern Atlantic tropical wave has its axis along 34W
from 02N-18N, moving westward at about 10-15 kt. This wave is
embedded within deep tropical moisture also associated with
the monsoon trough in that area of the Atlantic. Scattered
showers are noted along the wave axis mainly south of 10N.
A central Atlantic tropical wave has been repositioned based
on current satellite signature and wave diagnostics data. The
wave's axis is analyzed along 45W from 00N-16N. Scattered
showers are noted along the wave axis and within 45 nm on
either size of it.
A central Caribbean tropical wave has its axis along 77W from
00N-19N. Scattered moderate convection is noted south of 12N
between 73W-78W. There are scattered showers in the vicinity
of the northern portion of the wave also. This activity is
enhanced by a diffluent flow aloft.
The monsoon trough axis extends from the coast Africa near
20N16W to 10N30W to 09N44W. The ITCZ extends west of a tropical
wave from 07N49W to 06N58W. Aside from the convection described
in the Tropical Waves section above, scattered moderate
convection is within 300 nm south of the monsoon trough and
along the whole ITCZ.
GULF OF MEXICO...
Surface ridging prevails across the basin, ancjored by a 1015 mb
high centered near 28N93W. Latest scatterometer data depicts
light to gentle anticyclonic winds across the whole area, with
seas ranging between 2-4 ft. Scattered showers and tstorms are
noted over the Bay of Campeche, moving west with the thermal
trough that develops across the Yucatan peninsula every night.
This activity will dissipate during the morning hours.
The weak high pressure ridge will persist over the N Gulf this
week, maintaining gentle flow across much of the region with
moderate winds expected in the southwestern Gulf.
Refer to the section above for details on the tropical wave over
the central part of the basin.
Scattered showers and thunderstorms prevail north of 18N and
west of 75W enhanced by a diffluent pattern aloft. To the
south, the EPAC monsoon trough extends along 10N between 75W-83W
enhancing shower activity across this area. Scatterometer data
depicts gentle to moderate trades across the basin except south
of 15N between 66W-72W, where moderate to fresh easterly winds
The Bermuda High north of the area along with the eastward
extension of the NE Pacific monsoon trough will contribute
toward fresh to strong E trades over the central Caribbean
through Fri. Elsewhere, winds and seas are quiescent. No
tropical cyclone formation is expected in these waters for the
next several days.
Refer to the sections above for details on Hurricane Isaias and
the tropical waves moving across the basin.
Scattered showers are noted over the west Atlantic mainly west
of 74W. To the east, a surface trough extends from 28N65W to
24N65W. Although a weak area of low pressure is expected to form
over the next day or so from this trough, abundant dry air
surrounding the system is likely to limit significant tropical
development. A stationary front enters out area from 31N51W to
29N59W. Scattered showers are noted along the front. Surface
ridging prevails across the remainder of the basin, anchored by
a 1022 mb high centered near 22N50W.
Large seas north of 29N associated with Hurricane Isaias will
spread northward across the waters west of 75W during the next
few hours and then gradually subside late tonight through Tue
night. The trough along 65W will move NW across the west
Atlantic through today.