Tropical Weather Discussion
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AXNT20 KNHC 220020 CCA

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
805 PM EDT Sun May 21 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 1800 UTC surface analysis and satellite imagery through
2315 UTC.


A tropical wave is in the eastern Atlantic with axis extending
from 12N32W to 03N33W, moving west at 10 kt. Based on current
SAL analysis from UW-CIMSS, african dust is N and W of the wave.
Scattered showers are confined to the ITCZ.

A tropical wave is over the E Caribbean with axis extending from
18N65W to N Venezuela near 08N65W, moving west at 15 kt.
Scattered showers are within 120 nm of the wave axis.


The Monsoon Trough enters the tropical Atlantic near 09N13W and
continues to 07N22W. The ITCZ extends from 07N22W to 07N32W,
then resumes west of a tropical wave at 07N35W to the coast of N
Brazil near 04N51W. Scattered moderate to strong convection is
along the coast of western Africa along the monsoon trough from
03N-12N between 12W-16W. Isolated moderate convection is along
the ITCZ from 03N-09N between 39W-55W.



As of 21/2100 UTC, A 1021 mb High is located over the W Atlantic
near 31N76W. A ridge axis extends W to Lousiana. 10-15 kt SE
surface winds are over the Gulf of Mexico. A quasi-stationary
front is inland over S Louisiana, and S Texas with scattered
moderate convection extending 60 nm into the Gulf of Mexico.
Also, scattered moderate convection is over the NE Gulf N of 26N
between 85W-90W. Elsewhere, isolated moderate convection is
inland over central and N Florida. In the upper levels, an upper
level trough is over Texas. Upper level diffluence is over the N
Gulf N of 27N enhancing convection over the N Gulf States.
Expect over the next 24 hours for the front to remain inland,
thus little change is expected over the Gulf of Mexico.


A tropical wave is over the E Caribbean. Please see above.
Elsewhere, 15-25 kt tradewinds are over the Caribbean Sea.
Strongest winds are over the central Caribbean. Widely scattered
moderate convection is over the SW Caribbean and Central America
S of 16N. Scattered showers are over E Cuba, Jamaica,
Hispaniola, and Puerto Rico. Expect little change over the next
24 hours.

Daytime heating, local sea breezes and mountain upslope lifting
will combine with available moisture to produce scattered
showers and isolated thunderstorms mainly during the afternoon
and early evening hours.


A 1021 mb high is located over the W Atlantic near 31N76W. A
1016 mb low is located N of the Leeward Islands near 24N60W. A
1025 mb high is centered over the E Atlantic near 28N24W. Of
note in the upper levels, an upper level low is centered near
25N60W. Upper level diffluence E of the low center is producing
scattered moderate convection from 25N-28N between 54W-57W.
Expect in 24 hours for a cold front to move into the central
Atlantic and extend from 31N44W to 29N54W to 31N62W with

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