000 AXPZ20 KNHC 060322 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 150 UTC Tue Feb 6 2018 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 0000 UTC surface analysis and satellite imagery through 0245 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from 08N73W to 06N77W to 07N85W to 06N90W. The ITCZ continues from 06N90W to 05N100W to 07N109W to 06N116W to 09N125W. The ITCZ resumes from 10N128W to 09N136W to beyond 08.5N140W. Scattered moderate convection is noted from 07N to 10N between 135W and 140W. A surface trough reaches from 09N127W to 19N124W. This trough is the surface reflection of a mid to upper-level low centered near 22N129W. Scattered moderate and strong convection associated with this trough is occurring within an area bounded by 11N126W to 16N116W to 19N124W to 11N126W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A 1029 mb high pressure center remains located over the NE Pacific near 41N134W. A weak and elongated ridge extends SE into the offshore waters to SE of the Revillagigedo Islands. The pressure gradient along and offshore of the Baja California peninsula is yielding gentle to moderate NW winds this evening, with seas generally running 3 to 5 ft. This fairly quiet pattern should prevail through Wednesday. Long period NW swell will cause seas to build to 5-7 ft along the offshore waters N of 20N Tue and Wed. Seas in this region will then begin to subside on Thu. Light to gentle winds and 3 to 5 ft seas will prevail along the Pacific coast of Baja Fri and Sat. Gulf of California: Light to gentle winds and 1 to 3 ft seas will generally prevail through Wednesday. A modest increase in NW winds during mid week will cause seas to build to 3-4 ft, possibly as high as 5 ft Wed evening through Thursday. A low pressure trough will develop over the Baja Peninsula on Fri and Sat. S to SW winds over the Gulf of California E of the trough could become strong on Sat in advance of an approaching cold front. Gulf of Tehuantepec: Strong N winds will taper to light and variable by Tue evening. The pressure gradient over the Isthmus of Tehuantepec will tighten by early Thu as high pres builds southward along the Sierra Madre Oriental mountains of Mexico, while a cold front enters the NW Gulf of Mexico. Another gale force gap wind event may commence over the Gulf of Tehuantepec Thu evening through Fri night as this pattern develops. This event will peak on Fri morning and produce an area of 8 ft seas that will merge with the area of 8 ft seas propagating downwind from the Gulf of Papagayo. The merged area will spread as far S as 06N and as far W as 105W. Winds over the Gulf will decrease once again to light and variable by Sat night. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Fuego Volcano in Guatemala: Intermittent expulsions of volcanic ash from the volcano occurring during the past several days have not been detected since Sun. No lingering ash is evident in satellite imagery extending W or SW across the regional waters. Nocturnal winds will pulse to between fresh and strong speeds each night over the Gulf of Papagayo through the week. Areal coverage of gap winds near the Gulf of Papagayo will increase Thu and Fri. This will allow the wind generated seas of 8 ft to propagate further downwind from the Gulf of Papagayo and merge with the area of 8 ft seas downwind from the Gulf of Tehuantepec on Fri and Sat. Elsewhere N of 09N, gentle to moderate offshore flow will prevail. Moderate to fresh winds will pulse to strong during overnight hours in the Gulf of Panama as well through Wed morning, becoming moderate to fresh Thu and Fri. Otherwise, light to gentle S to SW winds will generally prevail S of 09N through Fri night. REMAINDER OF THE AREA... The ridge of high pressure mentioned above also extends S across the NW part of the discussion area this evening, and will persist during the next several days. NW swell generated by a fetch of winds to the W of a nearly stationary frontal boundary currently NW of the Hawaiian Islands has spread across the W portion of the discussion area and is generating seas of 8 to 9 ft W of a line from 30N128W to 18N129W to 05N140W. The NW swell will continue to propagate SE and decay. This will allow the associated area of seas to subside below 8 ft by Tue night. A residual area of 8 ft seas will linger from 07N to 15N between 115W and 121W by Wed evening. The next significant pulse of NW swell is not expected to enter the area waters until Fri night. Weather for the remainder of the week looks benign with only light to moderate winds and 4-7 ft seas anticipated beyond 250 nm offshore. A persistent surface trough currently extending from 09N127W to 19N124W is producing active convection along and E of the trough, described above and supported by a broad upper level cyclone centered near 22N129W. The trough will remain near its current location and eventually dissipate by Sat as the mid to upper-level low to the NW weakens, with associated convection gradually diminishing in coverage. $$ CAM