000 AXPZ20 KNHC 062155 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 2205 UTC Mon Feb 6 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 1800 UTC surface analysis and satellite imagery through 2100 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The ITCZ axis extends from 03N110W to 02N120W to 01N130W to 03N136W. Scattered moderate convection is from 03N to 05N between 110W and 115W. Similar convection is noted from 07N to 09N between 122W and 125W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Winds have diminished to 20-25 kt across the Gulf of Tehuantepec and is forecast to be 20 kt or less by this evening. The next Gulf of Tehuantepec gap wind event, with gale conditions possible, is expected late Thursday night as strong high pressure builds southward across the Gulf of Mexico in the wake of a cold front. High pressure of 1021 mb centered near 26N121W extends a ridge southeastward to near the Revillagigedo Islands. The pressure gradient between the ridge, and weak troughing over the Gulf of California is supporting gentle to moderate northerly winds off the west coast of the Baja California peninsula. Seas in this area are in the 5-6 ft range. Light to gentle winds and seas 2 ft or less prevail over the Gulf of California, while gentle to moderate winds and seas 4-6 ft prevail off the southwest coast of Mexico. The 1021 mb high is forecast to remain nearly stationary through Tuesday, but strengthen slightly. It is then forecast to lift northward to near 32N122W by Wednesday afternoon. As this takes place, the pressure gradient between the associated ridging and the trough over the Gulf of California will tighten some allowing for fresh to locally strong northwest winds to materialize off the west coast of the Baja California peninsula as well as portions of the Gulf of California Tuesday night and Wednesday. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... The pressure gradient between high pressure centered over the southeast United States and the equatorial trough over the eastern north Pacific is supporting fresh to strong gap winds over the Gulf of Papagayo. The area of high pressure will weaken over the next couple of days which will help loosen the pressure gradient and diminish winds below advisory criteria over the Gulf of Papagayo by midweek. Northerly winds in the 15-20 kt range are expected across the Gulf of Panama and downstream to near 4N-5N. Otherwise, light and variable winds and 4-6 ft seas will prevail elsewhere. REMAINDER OF THE AREA... A ridge, associated with the aforementioned high pressure of 1021 mb continues to dominate the northern waters. Long period NW swell propagating through the northwest portion of the area is producing seas in the range of 8-10 ft range there. This swell train with a leading edge period of 17 to 18 seconds will reach from Los Cabos to the Equator at 128 tonight, and the Revillagigedo Islands late tonight into Tuesday morning, and to near 100W on Wednesday. A tight pressure gradient between the above mentioned high pressure center of 1021 mb and lower pressure in the vicinity of the ITCZ associated with a trough analyzed from near 09N135W to 03N138W is supporting an area of fresh to strong northeast trades west of the trough from 06N to 11N W of 132W, with resultant seas in the 8-10 ft range. Otherwise, moderate to fresh trades are present north of the ITCZ to near 20N and elsewhere west of 120W. The gradient west of the trough is forecast to weaken through Wednesday. This will allow for the fresh to strong trades to diminish. A recent scatterometer pass shows SW winds in the 20-25 kt range across the NW waters, particularly NW of a line from 30N136W to 26N140W. These winds are ahead of a 1010 mb low pressure located near 32N141W with a cold front extending SW from the low center. The tight pressure between this front and the high pressure over the NE forecast waters will allow winds to increase to near 35 kt across the far NW waters tonight into Tuesday morning with seas building to near 15 ft. The area of low pressure will lift out to the northeast this evening and tonight. A tight pressure gradient is forecast to persist across the NW corner through Wednesday as another deep low pressure system approaches from the west. This will maintain strong to near gale force southerly winds and seas up to 15-16 ft over the NW waters. The associated cold front is forecast to enter the NW part of the forecast area by Wednesday afternoon, reaching from 30N135W to 24N140W by Wednesday evening. At that time, expect fresh to strong winds on either side of the front. $$ GR