NHC Tropical Weather Discussion (East Pacific) National Hurricane Center - Tropical Weather Discussion (East Pacific)

  • NHC East Pacific Tropical Weather Discussion

    000 AXPZ20 KNHC 230257 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Sat Mar 23 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 0000 UTC surface analysis and satellite imagery through 0230 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A surface trough extends from the northern Costa Rica coast near 10N85W to 07N87W, where scatterometer from late Fri afternoon indicates that it transitions to the ITCZ and continues to 03N100W to 03N114W to 04N128W to beyond 05N140W. Scattered moderate convection is noted within 120 nm south of the ITCZ between 89W and 91W, within 30 nm of the ITCZ between 92W and 98W and also between 114W and 119W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Gulf of California: Fairly quiet conditions will continue through early next week, with seas remaining in the 1-3 ft range. The pressure gradient between high pressure of 1026 mb centered near 28N127W and troughing along the Baja California Peninsula will continue to generate fresh winds along the Pacific coast and offshore waters of the Baja Peninsula through this weekend before diminishing slightly by early Sun. Seas west of the Baja Peninsula are currently in the 7-9 ft range in a northwest swell. These seas will slowly subside through early Sat before a new set of NW swell propagates into the area, building seas to the 8-11 ft range by Sun. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gulf of Papagayo: Strong to near gale force northeast to east winds are currently blowing off the northern Costa Rican terrain to across the Gulf of Papagayo. A container ship with call sign "BKKF" reported northeast winds of 25-30 kt near 10N87W or about 80 nm west-southwest of Cabo Blanco, Costa Rica a few hours ago. These winds are forecast to pulse to near gale force during the late night and early morning hours tonight into Sat and again on Tue and Wed. Winds will be mainly at strong speeds during the remainder of the afternoon and night time hours for the next several nights. Gulf of Panama: Moderate to fresh north to northeast winds across the Gulf of Panama will increase to strong tonight and into early Sat afternoon reaching southward to near 05N, at which time they will diminish to mainly fresh speeds. These winds will again pulse to strong speeds on Sat night and into early Sun afternoon and diminish again to fresh speeds, and change little from those speeds into early next week. Seas are expected to reach a peak of 8 or 9 ft with these winds tonight and into early Sat afternoon. then be at about 8 ft afterwards. Between Ecuador and the Galapagos Islands, 4-5 ft seas in mixed swell will build to the range of 5-7 ft during the upcoming weekend as both long period SW and NW swell arrive. Light to moderate winds and 3-5 ft seas will be the general rule elsewhere through the upcoming weekend. REMAINDER OF THE AREA... A cold front has moved into the far northwest part of the area, and as of 00Z extends from near 32N130W to 27N140W. The front has ushered in a new set of northwest long-period swell, with seas currently peaking near 15 ft west of the front. The swell will propagate southeastward while slowly subsiding during the next several days. The cold front will slowly shift eastward before dissipating by Sun. A new cold front will approach a position from near 32N137W to 30N140W early on Sun, and move across the northwest waters Sun through Mon followed by yet another large set of long-period swell, with seas expected to peak near 13 ft Sun. In the tropical zone, the pressure gradient between high pressure of 1025 mb centered near 29N125W and lower pressure in the vicinity of the ITCZ is supporting fresh to strong northeast to east trade winds from 08N to 12N west of 127W. These winds are expected to diminish slightly by early Sat evening as the high pressure weakens slightly. Scattered moderate convection, being maintained by a mid to upper- level shortwave trough, is within 30 nm of 07N128W. Elsewhere, northwest swell propagating across the forecast waters is maintaining seas of 8 ft or greater across much of the forecast waters W of 110W. The areal coverage of 8 ft seas will slowly subside through Sat before the next swell once again builds seas above 8 ft across this area. $$ Aguirr […]