000 AXPZ20 KNHC 250902 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 902 UTC Fri Aug 25 2017 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 0900 UTC. ...SPECIAL FEATURES... Gale Warning associated with the remnant low of Kenneth: The remnant low of Kenneth was analyzed near 28N136W at 1009 mb. The pressure gradient between the low and high pressure ridging to the N and NE continues to support gale force winds in the NW semicircle along with large seas of 10 to 14 ft. Gale conditions are forecast to diminish to fresh to strong during the next 24 hours, with winds continuing to diminish to 20 kt or less by 48 hours along with any residual seas. Please refer to the High Seas Forecast issued under WMO/AWIPS headers FZPN03 KNHC/MIAHSFEP2 for more information. ..TROPICAL WAVES AND TROPICAL LOWS... A tropical wave is analyzed to the N of 06N along 88W moving W at 15 to 20 kt. Scattered moderate and isolated strong convection accompanies the tropical wave from 05N to 10N between 88W and 93W, and also from 11N to 14N between 86W and 90W. Model guidance suggests that a surface low may develop along this tropical wave during the next few days. A tropical wave is analyzed to the N of 11N along 103W/104W moving W at around 10 kt. Only isolated convection is occurring near the wave. This wave is forecast to become less defined during the next day or so. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough axis extends from 13N87W to 10N96W to 14N114W to 12N130W to low pressure near 11N138W to 08N140W. Scattered moderate and isolated strong convection is from 08N to 11N between 104W and 111W, and also from 09N to 12N between 113W and 123W. Scattered moderate convection is from 09N to 12N between 127W and 133W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A NW to SE oriented low level trough will meander E to W across the Baja California Peninsula and adjacent Gulf of California through the upcoming weekend, with a weak surface low developing intermittently along the trough over the central portion of the Gulf of California. A NW to SE oriented ridge extends across the Pacific waters just beyond 250 nm. The pressure gradient will support a moderate NW breeze across the waters W of the Baja California Peninsula through Sun, except becoming a fresh NW breeze during the evenings within about 90 nm of the Pacific Coast. Expect mainly 3 to 6 ft seas through the weekend. A weak cold front will move SE across the Baja Peninsula and Gulf of California on Mon night. Otherwise in the Gulf of California, light to gentle southerly flow will persist, except a brief moderate southerly breeze will develop intermittently just S of the developing low pres over the Gulf waters, roughly along 30N. A moderate NW breeze will follow the cold front on Mon night, which should stall along 28.5N on Mon evening. In the Gulf of Tehuantepec, gentle N drainage winds are forecast through the weekend at night, with gentle onshore flow during the day. Strong southwesterly monsoon flow and long period cross- equatorial swell, in the form 7 to 10 ft seas, will develop across the waters W of 98W at about 250 nm seaward on Sun, spreading toward coastal locations thereafter. By then a surface low may have developed along the N extension of a tropical wave. The low will move NW on Mon and Tue. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... In the Gulf of Papagayo, moderate nocturnal drainage is forecast to begin on Sun night. Otherwise, light and variable flow is expected N of the monsoon trough through early Mon, while moderate to locally fresh southerly winds are expected S of the monsoon trough axis, with 4 to 7 ft seas by early next week. REMAINDER OF THE AREA... Except as discussed in the special features paragraph, the subtropical ridge extends from 32N130W to near 18N116W, and is accompanied by moderate anticyclonic winds and 4 to 7 ft seas. Moderate to locally fresh southerly winds are forecast S of the monsoon trough today, increasing to a strong breeze from roughly 06N to 11N between 98W and 118W on Sat, and expanding out from 05N to 12N between 97W and 120W on Sat night, with seas building 7 to 10 ft. $$ Lewitsky