000 AXPZ20 KNHC 100949 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Fri May 10 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 0600 UTC surface analysis and satellite imagery through 0845 UTC. ...SPECIAL FEATURES... Gulf of California Gale Warning: The pressure gradient between deepening low pressure over the SW United States and an offshore high pressure ridge is enhancing gap winds over the northern Gulf of California. These SW gap winds are assumed to have recently reach at or near gale conditions, from the waters along the western coast in the area from near Isla El Muerto towards the coast near Puerto Penasco. A 0406 UTC ASCAT pass across portions of the northern Gulf showed 25-30 kt winds across central portions there. Computer models guidance suggests that strongest winds are currently along the west coast, and this area was not sampled. These strong winds will persist over the northern Gulf Fri and Fri night north of 29.5N, then gradually diminish as the ridge west of Baja California breaks down Sat morning. Otherwise, light to moderate winds will prevail over the central and southern Gulf through early next week. Please read the latest High Seas Forecast issued by the National Hurricane Center under AWIPS/WMO headers FZPN03 KNHC/HSFEP2 or at website https://www.nhc.noaa.gov/text/MIAHSFEP2.shtml for further details. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... A trough extends from 10N74W TO 09N90W TO 11N104W. The ITCZ continues from 09.5N105W TO 07N116W TO 08.5N131W to beyond 06N140W. Widely scattered moderate to strong convection is present from 03N to 07.5N E of 84W, and from 03.5N to 09.5N between 87W and 96W. Scattered moderate to strong convection is noted from 05N to 09.5N between 105W and 138W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... See above in Special Features for Gale Warning and forecast discussion for Gulf of California. A broad high pressure ridge extends from 30N140W to just southeast of the Revillagigedo Islands. A weak pressure gradient to the east of the ridge is supporting generally moderate westerly winds across the waters of Baja California Norte, and moderate NW to N winds to the south of Punta Eugenia. Seas across the area are generally 4-5 ft in mixed NW and SW swell, except around 6 ft offshore and south of Cabo San Lucas, where winds are slightly stronger at 15-20 kt. While agricultural fires persist over southern Mexico, low level winds are presently transporting the smoke northward toward the Gulf of Mexico. Therefore, no visibility restrictions are expected over the Pacific waters at this time. Low pressure developing off the coast of southern California will pull a weak surface trough across the northern waters on Fri. This will displace the ridge farther south into the weekend with fresh NW to N winds developing near the entrance to the Gulf of California and over the waters west of Cabo Corrientes. The surface ridge will become re-established along the northern boundary by Mon. Long-period cross equatorial SW swell will impact the open waters through early next week, with seas expected to peak at 6-8 ft Sun from Punta Eugenia to Cabo Corrientes. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Agricultural fires continue over Central America, but the low level flow is transporting the smoke northward over the Gulf of Mexico. Therefore, no visibility impacts are expected over the Pacific waters at this time. Widely scattered showers and thunderstorms are active south of 10N in the vicinity of the seasonal low pressure trough, and along the Pacific coasts from Guatemala to NW Costa Rica. A significant S to SW Southern Hemisphere swell event is reaching the Ecuador offshore waters tonight and will spread northward across the waters off Central America through Sat night. Another round of SW swell will move across the region Sun and slowly diminish through Tue. This will raise regional seas from 4-6 ft tonight, to 6-8 ft Sun through Mon. High and powerful surf should be expected along much of the coastlines during this time, with dangerous rip currents prevailing. No significant gap wind events are expected over the Gulf of Papagayo and Gulf of Panama through early next week, as gentle onshore wind flow is generally forecast through this period. REMAINDER OF THE AREA... A broad high pressure ridge extends from the NE Pacific through 30N140W to just southeast of the Revillagigedo Islands. A weak pressure gradient to the south of the ridge is supporting generally moderate or weaker NE tradewinds. Little change is expected during the next several days. Large, long period cross equatorial SW swell over the far southern waters will steadily propagate northward through this weekend. Recent altimeter data over the southern waters near 118W confirmed 10 ft seas moving across the Equator. Seas will build to 12 ft south of the Equator between 90W and 115W this morning with 8 ft seas spreading as far north as 13N by midday Sun. Seas will subside beginning Mon as the long period swell gradually decays in this region. $$ Stripling