Pacific Discussion

  • NHC East Pacific Tropical Weather Discussion
    by nhcwebmaster@noaa.gov (nhcwebmaster) on January 28, 2020 at 3:29 AM

    000 AXPZ20 KNHC 280329 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 242 UTC Tue Jan 28 2020 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 08N84W to 02N92W to 05N104W. The ITCZ begins near 05N104W and continues along 06N120W to 07N140W. Scattered moderate convection is from 06N to 09N between 80W and 86W, and from 02N to 10N W of 120W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Long period NW swell, with seas in the 8-12 ft range will continue to affect the forecast waters west of the Baja California through Fri. A strong and nearly stationary ridge extending across the forecast waters west of the Baja California peninsula supports moderate to fresh NW winds. A surface trough will develop along western Mexico Tue night, which will increase the pressure gradient in the region, thus resulting in fresh to strong NW winds N of Punta Eugenia and moderate to fresh winds along the Gulf of California through Thu. A cold front will enter the Gulf of Mexico Tue night and reach the Bay of Campeche Wed afternoon. Strong winds behind the front will funnel through the Chivela pass into the Gulf of Tehuantepec where nocturnal drainage flow will enhance the winds to near gale force through Thu morning. Looking ahead, the next Gulf of Tehuantepec gap wind event is forecast to begin Fri night with winds possibly reaching gale force Sat afternoon. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... A weak pressure pattern across Central America will prevail through Friday, which will support light to gentle variable winds across the offshore waters. Nocturnal drainage flow, however, will support moderate to locally fresh winds in the Gulf of Panama and in the Gulf of Papagayo. Seas across the region will be in the range of 4-6 ft. Otherwise, SW swell will propagate into the forecast waters between the Galapagos Islands and Ecuador, building seas to 7 ft Wed night into Thu. REMAINDER OF THE AREA... High pressure of 1030 mb is centered N of the area near 32N129W. The pressure gradient between the ridge and lower pressure in the vicinity of the ITCZ is supporting fresh to strong tradewinds N of the ITCZ to 20N and W of 125W. This area of high pressure will remain nearly stationary through Fri, with only minor fluctuations in strength. This will maintain the area of fresh to strong trades through Fri morning. The area of high pressure will weaken afterwards, which will loosen the pressure gradient and diminish the areal coverage of fresh trades over the weekend. Long period NW swell dominates the forecast waters N of the equator and W of 110W, with seas in the 8-11 ft range. Additional pulses of NW swell will propagate into the forecast waters, maintaining these seas through Sat. $$ Ramos