| HOME | ARCHIVES | FORECASTS | IMAGERY | ABOUT NHC | RECONNAISSANCE |

Eastern North Pacific Tropical Weather Discussion (Text)



000
AXPZ20 KNHC 170922
TWDEP 

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1005 UTC Sun Dec 17 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
meteorological analysis.

Based on 0600 UTC surface analysis and satellite imagery through 
0830 UTC.

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

The ITCZ extends from 06.5N92W TO 10N120W TO 08.5N134W TO beyond 
09.5N140W. Scattered moderate isolated strong convection is 
noted within 120 nm of the ITCZ between 102W and 117W. Scattered 
weak to moderate convection is noted from 07N to 17N W of 131W.

...DISCUSSION...

OFFSHORE WATERS WITHIN 250 NM OF MEXICO...

Gulf of California: A deep layered low pressure system has moved 
SE across the Pacific waters of Baja California Norte tonight 
and into the northern Gulf of California. This system supports a 
1004 mb surface low near 32N114W 1004 mb with a cold front 
extending SSW across Baja California Norte to 28N114W then 
continues SW and then W TO 25N124W TO 27N130W. The upper low has 
intensified in recent hours and is producing scattered moderate 
convection aloft to the N of 27N and within 75 nm E of the cold 
front. The front is expected to continue moving SSE and 
gradually dissipate over the S central Gulf on Mon. S to SW 
winds over the northern and central Gulf ahead of the front have 
strengthened. The main issue tonight will be the likelihood of 
strong W to NW winds over the northern Gulf as the surface low 
pressure shifts eastward into the Sonora Desert. While the fetch 
across the northern Gulf will be too limited to develop large 
seas, mariners should be aware of the possibility of strong 
gusty winds funneling through low lying areas of Baja California 
Norte through early Sun. Winds will diminish through early next 
week after the front dissipates. 

Across the Pacific offshore waters, NW winds have strengthened 
behind the front to 20-25 kt, and seas have built to around 15 
ft along 120W. Seas are expected to build to as high as 16 ft in 
NW swell by Sunday morning, then start to subside by afternoon. 
Seas of 8 to 10 ft will cover most of the waters beyond 60 nm of 
the Baja coast through early next week. Elsewhere gentle to 
moderate winds and 3 to 5 ft seas will persist along the coast 
of Mexico outside of the Gulf of Tehuantepec through mid week.

Gulf of Tehuantepec: A small plume of strong northerly winds 
continues across the Gulf of Tehuantepec tonight but will 
diminish quickly this morning through the afternoon. Starting 
tonight, nocturnal drainage winds will pulse to strong through 
midweek.

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

Strong offshore winds are occurring across the Gulf of Papagayo 
tonight and extend downwind to near 89W. These strong gap winds 
are expected to continue across the Papagayo region for the the 
next few days. Fresh N winds are funneling across the Gulf of 
Panama currently and will do so again tonight. 

REMAINDER OF THE AREA...

Fresh to strong winds prevail over the waters N of 24N, with 
seas 9 to 15 ft in northerly swell. Seas associated with this 
swell will peak near 16 ft early this morning before starting to 
subside. Moderate to fresh tradewinds prevail elsewhere over the 
forecast waters north of the ITCZ to 20N and west of 125W, and 
have diminished W of 135W tonight as a trough to the W of the 
area has moved farther W and away from the area. High pressure 
across the NE Pacific will dominate the regional waters for the 
next few days with little change in tradewinds. However the 
latest northerly swell event across the region will fade through 
Tue and allow seas to gradually subside to 6 to 9 ft areawide.

$$
Stripling

Standard version of this page

Alternate Formats
About Alternates - E-Mail Advisories - RSS Feeds

Cyclone Forecasts
Latest Advisory - Past Advisories - About Advisories

Marine Forecasts
Latest Products - About Marine Products

Tools & Data
Satellite Imagery - US Weather Radar - Aircraft Recon - Local Data Archive - Forecast Verification - Deadliest/Costliest/Most Intense

Learn About Hurricanes
Storm Names Wind Scale - Prepare - Climatology - NHC Glossary - NHC Acronyms - Frequently Asked Questions - AOML Hurricane-Research Division

About Us
About NHC - Mission/Vision - Other NCEP Centers - NHC Staff - Visitor Information - NHC Library

Contact Us


NOAA/ National Weather Service
National Centers for Environmental Prediction
National Hurricane Center
11691 SW 17th Street
Miami, Florida, 33165-2149 USA
nhcwebmaster@noaa.gov
Disclaimer
Privacy Policy
Credits
About Us
Glossary
Career Opportunities
Page last modified: Sunday, 17-Dec-2017 09:22:30 UTC