ABPZ20 KNHC 190516
Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 PM PDT Mon Sep 18 2017
For the eastern North Pacific...east of 140 degrees west longitude:
The National Hurricane Center is issuing advisories on Tropical
Storm Norma, located a couple of hundred miles west-southwest of the
southern tip of the Baja California peninsula, and on Tropical Storm
Otis, located more than 1000 miles west of the southern tip of the
Baja California peninsula.
An area of low pressure is expected to form toward the end of the
week south of southeastern Mexico. Some subsequent development is
possible as the system moves slowly west-northwestward near the
coast of Mexico.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 5 days...medium...50 percent.
AXPZ20 KNHC 190943
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1005 UTC Tue Sep 19 2017
Tropical Weather Discussion for the eastern Pacific Ocean from
the Equator to 32N, east of 140W. The following information is
based on satellite imagery, weather observations, radar, and
Based on 0600 UTC surface analysis and satellite imagery through
The center of Tropical Storm Otis at 19/0900 UTC is near 19.0N
127.9W, or about 1035 nm to the west of the southern tip of the
Baja California peninsula. Otis is moving WSW or 240 degrees, 3
knots. The estimated central pressure is 1005 mb. The maximum
sustained wind speeds are 35 knots with gusts to 45 nm. A move
toward the south is expected during the next 24 hours. Otis is
forecast to weaken into a post-tropical remnant low pressure
center in 24 hours, and to dissipate in 36 hours. The maximum
sea heights are 14 feet, and forecast to reach be less than 12
feet around sunset today, and to reach 8 feet by sunset on
Wednesday. Precipitation: convective debris clouds and possible
rainshowers from 19N to 22N between 125W and 130W. Please read
the latest NHC Forecast/Advisory under AWIPS/WMO headers
MIATCMEP5/WTPZ25 KNHC for additional details.
The center of Tropical Depression Norma at 19/0900 UTC is near
21.6N 113.9W, or about 235 nm WSW of Cabo San Lucas, Mexico.
Norma is moving W or 280 degrees, 05 knots. The estimated
minimum central pressure is 1007 mb. The maximum sustained wind
speeds are 30 knots with gusts to 40 knots. Norma will continue
to move NW during the next 36 hours. Norma is forecast to weaken
into a post-tropical remnant low pressure center in 36 hours,
and to dissipate in 48 hours. The sea heights will be less than
12 feet by sunrise of today. The area around Norma eventually
will continue to experience sea heights that will range from 9
feet to 10 feet by early Friday, because of NW swell that will
enter the forecast area by sunset today. Precipitation:
scattered moderate to isolated strong from 20N to 24N between
110W and 115W. Please read the latest NHC Forecast/Advisory
under AWIPS/WMO headers MIATCMEP2/WTPZ22 KNHC for additional
A tropical wave is along 91W/94W from 22N in the SW corner of
the Gulf of Mexico, across the Isthmus of Tehuantepec, into the
eastern Pacific Ocean. The wave is moving W 10 knots.
Precipitation: scattered strong from 12N to 16N between 94W and
99W. Scattered moderate to isolated strong is in the SW corner
of the Gulf of Mexico, and in Guatemala and Mexico from 15N to
20N between 90W and 96W.
INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
The monsoon trough passes through Panama near 10N85W, to 12N94W,
13N105W, to 12N117W, 15N124W, 15N131W, and beyond 12N140W.
Precipitation: scattered moderate to strong within 180 nm S of
the monsoon trough between 87W and 90W, within 60 nm N of the
monsoon trough between 87W and 92W, and within 120 nm N of the
monsoon trough W of 136W. scattered moderate to isolated strong
within 180 nm to 300 nm S of the monsoon trough between 105W and
OFFSHORE WATERS WITHIN 250 NM OF MEXICO...
Please refer to the special features section for more
information about Tropical Depression Norma. The wind speeds
that are in the area where Norma is now will reach 20 knots or
less starting after midnight on Wednesday, and remain at that
level through Saturday. Northwesterly swell of 8-11 ft will
reach the zones that are to the W of Baja California on
Wednesday and Thursday, and then they will diminish around
Saturday. Southwesterly swell of 8 to 9 feet, that is associated
with the monsoon trough, should reach the zones that are to the
south of southern and southeastern Mexico on Saturday.
Gulf of California...The winds will remain 20 kt or less, and
the sea heights will be less than 8 feet, through Saturday.
OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND
WITHIN 750 NM OF ECUADOR...
The winds will remain 20 knots or less, and the sea heights
will be less than 8 feet, through Saturday.
REMAINDER OF THE AREA...
Please refer to the special features section for details about
on Tropical Storm Otis. The wind speeds will remain 20 knots or
less through Saturday, after Otis has weakened on Wednesday.
A NW swell event will begin moving across our northern border
this afternoon at 30N with heights ranging from 8 to 11 feet.
This swell will propagate southward and reach 15N on Thursday,
diminishing to less than 8 feet on Friday and Saturday.