000 AXPZ20 KNHC 201002 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 657 UTC Fri Jan 20 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 0900 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The intertropical convergence zone extends from 04N91W to 05N101W to 04N113W to 07N135W to 07N140W. No significant convection. ...DISCUSSION... ...A series of strong cold fronts and a prolonged period of unusually large swell will affect much of the area during the coming week... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A cold front crossing Baja California Norte extends from 31.5N114W to 28N117W. The front will sweep across the northern Gulf of California and weaken today. Large northwest swell associated with the front will push southeastward and arrive along the west coast of Baja California today. Strong southwest winds ahead of the front north of 29N over the Gulf of California will diminish slightly today. A stronger cold front will sweep eastward over Baja California Norte tonight, accompanied by even stronger winds and higher seas. Large northwest swell will cause seas to build to 14-22 ft in the Pacific waters north of 25N through Sunday morning. Mariners can expect hazardous marine conditions in both the near shore and coastal waters. Very dangerous surf conditions will spread southward along the entire Pacific coast of Baja California. High pressure building in behind the front will support strong northerly flow off the southern Gulf of California and off Cabo Corrientes by late Sunday as the leading edge of the large NW swell event reaches the coast near Manzanillo. Another front will push into the waters off Baja California Norte by Monday morning. This front will bring another round of strong northwest winds and 12 to 18 ft northwest swell. Farther south, a cold front moving through the western Gulf of Mexico will prompt strong gap winds in the Gulf of Tehuantepec Sunday night and Monday morning. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Light to gentle southeast to east winds will generally prevail across the region through Tuesday. Seas will be generally 3-5 ft in the forecast waters. REMAINDER OF THE AREA... A ridge extends eastward along 24N to the southern tip of the Baja peninsula. The gradient between the ridge and low pressure associated with the ITCZ is supporting a decreasing area of fresh northeast trade winds west of 133W, with 8-10 ft seas. Moderate to fresh trades are observed elsewhere from 07N to 20N west of 122W. Seas where fresh trades are present range between 7 and 8 ft in mixed NE and NW swell. Expect the trades to decrease in areal coverage and shift westward through Saturday as the ridge to the north weakens. A second cold front is expected to quickly sweep southeastward across the northern waters today and tonight. Wave model guidance shows unusually large northwest swell propagating southeastward into the waters north of 20N behind the second front, with seas building to 16-22 ft north of 25N Saturday. Yet another cold front will move into the far northwest waters on Saturday, preceded and followed by strong to near gale force winds. NW winds behind the front could reach gale force N of 28N and W of 130W on Sunday and Sunday night. This front will generate another set of large northwest swell through the northwest waters, with wave model guidance indicating seas in the 14-22 ft range. $$ cam