000 AXPZ20 KNHC 312153 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2153 UTC Thu Jan 31 2019 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 1800 UTC surface analysis and satellite imagery through 2100 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The ITCZ extends from 03N95W to beyond 09N140W. No significant shower or thunderstorm activity is observed. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Broad and weak ridging extends SE from near 32N136W southeastward through the Revillagigedo Islands. The weak pressure gradient between the ridge and a surface trough along Baja California supports gentle to moderate NW winds over the offshore waters N of Cabo San Lazaro. Light and variable winds prevail off Baja California Sur through the waters off of southern Mexico. Wave heights are 3 to 5 ft, with the highest off Baja California Norte. Winds will weaken slightly today as a weak cold front approaches the area from the NW, and moves into Baja California Norte tonight where it will stall and dissipate. Gulf of California: Gentle S flow across most of the Gulf will be replaced by a brief pulse of fresh S to SW winds north of 29N this evening, as a mid/upper level disturbance moves southeast along the coast of southern California, transporting a weakening cold front over the northern Gulf of California. This front will dissipate by dawn on Fri. Winds will shift NW early Fri behind the front, then diminish as the front continues southward and weakens. Seas will peak around 5 ft overnight across far north portions of the Gulf. Looking ahead, the next cold front moving across Baja California Norte and the northern Gulf of California Sat evening through early Sun night will bring another pulse of strong S to SW winds to the northern Gulf of California during this time frame. The front will also be accompanied by longer period NW swell of 8 to 11 ft reaching Guadalupe Island and the northern portion of Baja California Norte by Sat afternoon. The swell will decay as it moves southward, but seas of 8 to 10 ft will cover the waters off Baja California through Tue morning. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: Fresh to strong NE winds are expected during the overnight and early morning hours through early next week with these winds peaking around 30 kt tonight. Gulf of Panama: Expect fresh to strong N to NE winds especially at night through Fri night. Seas downstream of the Gulf are expected to reach 6 to 8 ft as far SW as 07N100W Wed through Fri. A modest SW swell will begin to move into the regional waters late this afternoon through this weekend and augment sea heights a few feet. REMAINDER OF THE AREA... A prominent deep layer cutoff low centered ENE of the Big Island of Hawaii near 23N144W continues to support a surface trough west of 140W. The pressure gradient between the surface trough and high pressure farther north will support E to SE fresh to strong winds from 15N to 25N W of 135W until this afternoon, when the ridge weakens and shifts E as the area of low pressure lifts N and weakens. Diffluent flow to the east of the middle to upper level low along with abundant moisture in the tropics continues to support scattered showers and thunderstorms in this region as well. Scattered moderate and isolated strong convection associated with this system is occurring over the forecast waters from 17N to 25N and W of 135W. Seas of 8 to 11 ft in this area will subside to between 8 and 9 ft through early Fri as the winds diminish, but persist into Fri night due to NW swell continuing to move into the region. Farther north, a cold front north of 29N today will sweep east and dissipate tonight over Baja California and the northern Gulf of California. Another cold front is approaching the area from the west, and will move into the discussion area this evening. The front will reach from 30N130W to 24N140W by late Fri accompanied by fresh to occasionally strong NW winds. Long period NW swell of 8 to 12 ft will also accompany the front as it moves across the waters north of 20N and approaches Baja California Norte by Sat evening. High pressure building in the wake of the front will support fresh to strong trade winds from 20N to 25N west of 135W early next week. $$ Christensen