AXPZ20 KNHC 242135
Tropical Weather Discussion
NWS National Hurricane Center Miami FL
2205 UTC Mon Oct 24 2016
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 1800 UTC surface analysis and satellite imagery through
Hurricane Seymour is rapidly intensifying and it is expected to
become a major hurricane tonight or Tue. At 24/2100 UTC, it is
located near 15.3N 111.3W, moving west-northwest or 285 deg at 13
kt. Maximum sustained winds have increased to 85 kt with gusts to
105 kt. Minimum central pressure is 984 mb. Numerous strong
convection is noted within 60 NM of the center of Seymour while
scattered moderate to strong convection is seen elsewhere from
12N to 18N between 109W and 114W. Conditions remain favorable for
continued intensification during the next few days as Seymour
continues moving W-NW. A turn toward the northwest should occur by
Wednesday. Although the forecast track keeps Seymour just outside
of the Mexican offshore zones, fresh to strong winds and seas in
the 8-10 ft range are expected to affect the southern part of
zones PMZ023 through tonight and PMZ015 through late Tue. For
additional details on Seymour, refer to the latest NHC
forecast/advisory under AWIPS/WMO headers MIATCMEP5/WTPZ25.
A gale warning will remain in effect for the Gulf of Tehuantepec
during the next 48 hours, as strong northerly winds will persist
throughout the week across this region. By Thursday night into
early Friday morning, the aerial extent of the gale force winds
will increase as high pres builds across the western Gulf of
Mexico. At that time, seas are expected to build to 10-14 ft.
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
The monsoon trough extends across the Gulf of Panama near 08N79W
to 07N90W to 09N100W. It resumes W of hurricane Seymour from a
1010 mb low pres near 18N118W to 1011 mb low pres near 15N127W to
beyond 11N140W. Scattered moderate isolated strong convection is
from 04N to 07N between 78W and 85W. Similar convection is from 06N
to 10N between 98W and 102W.
OFFSHORE WATERS WITHIN 250 NM OF MEXICO...
See special features for details on the Gulf of Tehuantepec gap
wind event. High pres of 1018 mb is centered near 27N120W and is
producing light anticyclonic winds across the waters W of the Baja
California Peninsula. Combined seas there are 4-6 ft across
southern portions of the peninsula, and 5 to 8 ft N of 27N due to
long period NW swell moving into the region. Seas here will
subside below 8 ft by Tuesday. The high pres will shift slightly
N-NE during the next 24 hours. This will result in moderate NW
winds across the offshore waters.
Inside the Gulf of California, mainly gentle southerly winds
prevail across the north half, while gentle N to NW winds prevail
across far southern portions. By this evening, gentle to moderate
NW winds will dominate all the waters S of 27N extending SE to
between Los Cabos and Las Tres Marias Islands. On Tuesday, as the
high center shifts farther N-NE, NW winds will spill down the
entire length of the Gulf of California.
OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND
WITHIN 750 NM OF ECUADOR...
Gulf of Papagayo: Winds will pulse over the Gulf of Papagayo over
the next couple of days. Winds will peak near 20 kt during the
late night and early morning hours and diminish to near 15 kt
during the afternoon and early evening hours.
Elsewhere gentle to moderate S to SW winds are noted S of the
monsoon, while mainly gentle W to NW winds prevail N of the
monsoon trough. Combined seas are in the 4 to 6 ft range, primarily
in long period SW swell which is dominating the offshore waters.
These marine conditions will persist over the few days.
REMAINDER OF THE AREA...
A weak ridge dominates most of the north waters N of 20N, and is
producing mainly light and variable winds between 20N and 30N.
Outside Seymour, two weak low pres centers are noted along the
monsoon trough near 18N118W and near 15N127W. Seas of 8-10 ft in
NW swell are observed per a pair of altimeter passes N of 15N
between 117W and 121W. Seas over this area are forecast to subside
to less than 8 ft by Tuesday.
A cold front is over the NW waters and extends from 30N135W to 28N140W.
Moderate to fresh SW winds are noted N of 28N ahead of the front
to 130W. This front will become stationary tonight extending from
30N134W to 27N140W. A second and stronger cold front will reach
the NW waters by early Tue afternoon. The merging cold front is
forecast to extend from 30N132W to 24N140W by early Wed afternoon.
SW winds ahead of the second front will increase to 20-25 kt on
Tue with seas building to 8-10 ft across most of the NW waters NW
of a line from 30N131W to 27N136W.