064 
AXPZ20 KNHC 220940
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1005 UTC Sun Oct 22 2023

Tropical Weather Discussion for the eastern Pacific Ocean from
03.4S to 30N, east of 120W including the Gulf of California, and
from the Equator to 30N, between 120W and 140W. The following
information is based on satellite imagery, weather observations,
radar, and meteorological analysis.

Based on 0600 UTC surface analysis and satellite imagery through
0930 UTC.

...SPECIAL FEATURES...

Tropical Storm Norma is centered near 24.5N 109.8W at 22/0900
UTC, moving north-northeast at 6 kt. Estimated minimum central
pressure is 990 mb. Maximum sustained wind speed is 50 kt with
gusts to 60 kt. Peak seas are around 24 ft. Scattered moderate 
convection and thunderstorms are ongoing in the southern Gulf of
California between Baja California Sur and Sinaloa. On the 
forecast track, the center of Norma is forecast to approach the 
west coast of mainland Mexico today and move inland within the 
tropical storm warning area on tonight or early Monday. Little 
change in strength is forecast today, and Norma is expected to 
approach the west coast of mainland Mexico as a tropical storm. 
Rapid weakening is anticipated once Norma moves inland over 
mainland Mexico. Please consult products from your local weather
office and read the latest HIGH SEAS FORECAST issued by the 
National Hurricane Center at website 
- https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml and the latest 
Norma NHC Forecast/Advisory and Public Advisory at 
www.hurricanes.gov for more details.

South of Southern Mexico (EP91): Recent satellite wind data 
indicate that the circulation associated with a broad area of low
pressure located several hundred miles south of the Gulf of 
Tehuantepec has become better defined. However, the associated 
shower and thunderstorm activity is displaced well to the 
northwest and west of the center. The upper-level winds are 
expected to become more conducive for development of this system,
and a tropical depression is likely to form during the next 
couple of days. The system is forecast to meander or drift 
generally northward through early next week. This system has a 
high chance of tropical cyclone formation through 48 hours. 
Please read the latest NHC Tropical Weather Outlook at 
www.hurricanes.gov for details.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...

The monsoon trough extends from the coast of Costa Rica near 
09N84W to low pres near 09N96W 1007 mb to 09N120W to 07N126W. 
The ITCZ extends from 07N126W to 05N135W to 06N140W. Scattered 
moderate convection is from 03N to 10N E of 93W, and from 06N to
12N between 102W and 120W. Numerous moderate to strong 
convection associated with Invest EP91 is ongoing from 07N to 13N
between 94W and 100W.
 
...OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

Please see the SPECIAL FEATURES section above for more details
on Tropical Storm Norma and Invest EP91.

The pressure gradient between the subtropical ridge to the west
of the Baja California Peninsula and Norma is supporting moderate
to fresh N to NW winds along the Baja Peninsula offshore waters.
Seas are 8 to 10 ft in mixed swell N of Cabo San Lazaro and 8 to
16 ft southward to the entrance of the Gulf of California and
Jalisco offshore waters. In the Gulf of California N of 27N, 
gentle to moderate SE winds are ongoing along with seas to 3 ft. 
EP91 is producing moderate to locally fresh winds in the southern
portions of the Tehuantepec offshore waters along with seas to 8
ft. The remainder SW Mexican offshore waters are under the
influence of light to gentle variable winds and seas to 9 ft in 
mixed swell.

For the forecast, Norma will move to 25.0N 109.2W this 
afternoon, inland to 25.3N 108.5W Mon morning, weaken to a 
remnant low near 25.7N 107.6W Mon afternoon, and dissipate Tue 
morning. Elsewhere, locally strong winds will develop this
evening across the Baja California offshore waters N of Cabo San
Lazaro and will continue through Mon morning. NW swell across 
the Baja California offshores along with swells generated by 
Norma will continue to result in confused and hazardous seas at 
the entrance of the Gulf of California through today. A new set 
of NW swell will enter the offshores of Baja California Norte N
of Punta Eugenia Mon night and subside Wed morning. Regardless of
development, EP91 is forecast to generate fresh to strong winds
into the Tehuantepec offshore waters Mon through Wed. 

...OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, 
AND WITHIN 750 NM OF ECUADOR...

Please see the SPECIAL FEATURES section above for more details
on Invest EP91.

The broad low pressure associated with EP91 located well south 
of the Gulf of Tehuantepec is supporting moderate to fresh E to 
SE winds across the offshore waters of Guatemala and El 
Salvador S of 12N. Otherwise, light to gentle winds are noted 
north of the monsoon trough. South of the monsoon trough, gentle 
to moderate S winds prevail. Seas range are 5 to 8 ft across the
offshore waters with the higher seas to 9 ft closer to EP91. 
Scattered showers and tstms continue across the offshore waters 
between Colombia and Costa Rica.  

For the forecast, winds will begin to increase to locally fresh 
across the South America and Galapagos Islands offshore waters 
briefly on Mon. Mixed swell may build slightly in offshore 
Galapagos Islands to Ecuador by tonight. NW swell will bring 
seas up to 8 ft west of the Galapagos Islands later today, with 
SW swell increasing seas to 7 ft in the Ecuador and portions of 
Central American offshores through Mon. Seas will subside by 
midweek. EP91 has the potential to develop into a tropical 
depression by early next week as it meander or drift generally 
northward. Expect moderate to locally fresh winds and seas to 8 
ft in the Guatemala and El Salvador offshore waters the next few 
days. 

...REMAINDER OF THE AREA...

Please see the SPECIAL FEATURES section above for more details 
on Tropical Storm Norma and Invest EP91.

Surface ridging extends across the northern forecast waters, N 
of 16N and W of 120W. This is supporting gentle to moderate N to
NE winds from 07N to 24N and W of 120W. S of the monsoon trough,
gentle to moderate S to SW winds are noted. Large NW swell 
continues to propagate across most of the waters between 92W and 
124W with 8 to 11 ft seas. 

For the forecast, other than the low pressure (EP91), Norma will
move to 25.0N 109.2W this afternoon, inland to 25.3N 108.5W Mon 
morning, weaken to a remnant low near 25.7N 107.6W Mon afternoon,
and dissipate Tue morning. 

Elsewhere, a weak pressure pattern will support mainly gentle to
moderate winds across the open waters through today. Winds may 
increase moderate to fresh on Mon as high pressure builds N of 
the area and tightens the pressure gradient. Meanwhile, a new set
of NW swell is forecast to spread S of 30N to the E of 130W by 
Mon morning, potentially building seas to 10 ft N of 25N.

$$
Ramos