000 AXPZ20 KNHC 080247 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 0405 UTC Mon May 8 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 0000 UTC surface analysis and satellite imagery through 0200 UTC. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 04.5N80W to low pres near 07.5N89.5W 1008 MB to low pres near 10.4N104W 1009 MB TO 04N113W. The ITCZ extends from 04N113W TO 07N125W to beyond 06N140W. Scattered moderate to strong convection is noted from 04.5N to 07.5N between 92W and 102W. Widely scattered moderate isolated strong convection is noted within 90 nm N and 150 nm S of axis between 105W and 127W. Scattered moderate to strong convection is noted from 03N to 10N between 83W and 92W associated with low pres near 07.5N89.5W. Scattered moderate to strong convection is noted from 09N to 13.5N between 98W and 106W associated with low pres near 10.5N104W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Weak low pressure is developing across the northern Gulf of California this evening, with fresh winds across the N semicircle and strong winds across the S semicircle to near 29N. Seas are estimated to be 3-6 ft in this area. Little change is expected during the next several hours before the low moves N and inland and dissipates shortly after sunrise. Due to this, winds and seas will gradually diminish late tonight through Monday morning. Fresh to strong NWly winds prevail over the coastal waters off the coast of Baja California Norte with seas in the 8-13 ft range in northerly swell. Elsewhere moderate to fresh NW winds with seas in the 4-7 ft range prevail over the open waters from Baja California Sur to Cabo Corrientes. Winds off the coast of Baja California Norte will diminish to 20 kt or less on Monday. Seas will peak near 13 ft over this area during the next several hours then start to subside Monday morning, falling below 8 ft by midweek. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Gentle to moderate winds prevail over the forecast waters with seas in the 4-6 ft range. An elongated cyclonic circulation has developed over the region. Upper atmospheric conditions will remain conducive for sustained deep convection through the middle of next week across central America and adjacent offshore waters to southeastern Mexico, as abundant moisture converges about the elongated trough. Global models are in good agreement with the development of a low pressure area within this larger gyre, but disagree on the precise location, and strength, of this low. However, within this broad gyre, active convection over a large area could lead to periods of heavy rainfall across portions of the region from Costa Rica to SW Guatemala. Evening satellite imagery and afternoon ASCAT data suggest that a broad cyclonic circulation has begun to develop across this area, centered near 07.5N89.5W and is moving little. As mentioned above, scattered moderate to strong convection is noted from 03N to 10N between 83W and 92W within this broad developing circulation. This area will continue to be monitored for improved organization and heavy rainfall potential along adjacent coastal zones. REMAINDER OF THE AREA... High pressure of 1032 mb centered north of the area near 34N138W extends a ridge southeast to just SE of the Revillagigedo Islands. The pressure gradient between this area of high pressure and lower pressure over the southwest United States is supporting fresh to strong winds over the northern waters east of 130W. Large northerly swell generated by gale force winds off the coast of California is bringing seas up to 15 ft into the northern waters east of 127W. This northerly swell is producing seas greater than 8 ft over the of the waters north of 20N and west of 113W. Elsewhere, gentle to moderate winds with seas in the 5-7 ft range prevail. The area of high pressure will weaken early this week which will diminish winds over the northern waters. Seas peaking near 16 ft today into Monday will start to subside, falling below 8 ft by midweek. $$ Stripling