Pacific Discussion

  • NHC East Pacific Tropical Weather Discussion
    by nhcwebmaster@noaa.gov (nhcwebmaster) on October 19, 2021 at 9:54 AM

    000 AXPZ20 KNHC 190954 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Tue Oct 19 2021 Tropical Weather Discussion for the eastern Pacific Ocean from 03.4S to 30N, east of 120W including the Gulf of California, and from the Equator to 30N, between 120W and 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 0930 UTC. ...TROPICAL WAVES... A tropical wave is along 84W north of 03N through Costa Rica, Nicaragua and E Honduras moving west at 10 to 15 kt. Scattered moderate convection is N of 06N between 80W and 86W. A tropical wave extends along 91W north of 02N to Guatemala, moving westward at 10-15 kt. Numerous moderate to strong convection is N of 10N between 86W and 94W. A tropical wave extends along 127W from 04N to 15N, moving westward at 15 kt. Scattered moderate convection is from 07N to 13N between 117W and 131W. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from 07N78W to 10N91W to 08N100W to 1011 mb low pressure near 11N111W to 09N127W to 13N140W. Aside from the convection associated with the tropical waves discussed in the section above, scattered moderate convection is observed from 05N to 14N between 96W and 104W, and from 07N to 14N between 106W and 114W. Scattered moderate isolated strong convection is from 11N to 15N W of 132W. OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Fresh to near gale force N to NE winds continue over the Gulf of Tehuantepec with seas to 8 ft N of 13N. Scattered showers and tstms are also in the Tehuantepec region due to a tropical wave approaching from the E. Farther north, a weak cold front continues to move across Baja California Norte and the northern Gulf of California where it is supporting fresh N winds. A weak pressure gradient across the region is supporting gentle to locally moderate NW winds across the remainder Mexican offshore waters with 3 to 5 ft seas primarily in SW swell. Winds over the Gulf of Tehuantepec will diminish to moderate to fresh on Wed. Fresh to strong NE to E winds will resume again Wed night through Thu night as a surface trough moves across the Bay of Campeche. An area of disturbed weather located a few hundred miles S of the coasts of Guatemala and El Salvador may undergo gradual development during the next several days, and a tropical depression could form late this week or this weekend while the system moves WNW to NW near or just off the coast of southern Mexico. The cold front will move to just S of Punta Eugenia late this afternoon before stalling and dissipating tonight. NW swell associated with the front supporting seas to 7 ft N of Cabo San Lazaro will subside tonight. Otherwise, another larger set of NW swell will start to move into the waters near Guadalupe Island by Thu, bringing seas in excess of 8 ft to all the offshore waters of Baja California Fri and Sat. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, and WITHIN 750 NM OF ECUADOR... Moderate to locally fresh E winds are N of the monsoon trough and across the Nicaragua, El Salvador and Guatemala offshore waters associated with an area of disturbed weather that have the potential of undergoing gradual development during the next several days. To the S of the monsoon trough, gentle to moderate SW winds prevails along with seas to 5 ft in SW swell. A tropical depression could develop from the disturbance late this week or this weekend while the system moves WNW to NW near or just off the coast of southern Mexico. Regardless of development, moderate to locally fresh winds will affect the Guatemala and Nicaragua offshore waters through early Thu. Otherwise, gentle to moderate SW winds will dominate the remainder offshore waters S of the monsoon trough through the forecast period. REMAINDER OF THE AREA... Moderate to locally fresh NE winds continue over the waters N of the monsoon trough and west of 120W, with gentle to moderate winds south of the monsoon trough. Gentle to moderate N to NE winds and seas in the 5-7 ft range will change little today. A NW swell expected to raise seas to 8 ft will move into the waters N of 27N between 120W-130W today into Wed, then subside. Looking ahead, another round of NW swell will accompany a cold front that will move into the waters N of 28N and W of 130W tonight, with seas in excess of 8 ft dominating the waters NW of a line from Guadalupe Island to 14N140W by late Thu. Reinforcing NW swell will follow over the same area through Sat. $$ Ramos