000 AXPZ20 KNHC 310920 TWDEP Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Wed May 31 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... A broad area of low pressure south of southeastern Mexico is centered near 14N99W with an estimated pressure of 1008 mb. Scatterometer data at 0418 UTC showed 25 kt winds displaced northeast of the broad low level center along the Guerrero and Oaxaca state coasts of southern Mexico. Numerous moderate to strong convection is located mainly south of the circulation center within 75 nm of 12.5N99W. The low is expected to slowly become better organized today as it drifts northward. Abundant deep layer moisture associated with the low will be favorable for very active weather in the form of widespread shower and thunderstorm activity during the next 2-3 days. Locally heavy rain may cause life-threatening flash floods and mudslides. The hurricane center outlook says a tropical depression is likely to form in the next day or two as it slowly moves northward towards the coast of Mexico. ...TROPICAL WAVES... A tropical wave axis is north of 03N along 80W, moving west at 10 to 15 kt. Isolated showers and thunderstorms are noted within 60 nm of the axis. The wave is expected to help increase shower and thunderstorm activity over much of Honduras, Costa Rica and Panama through the next 48 hours or so as it interacts with the monsoon trough across central America. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 09N76W across Panama and Costa Rica to 10N86W, then along the west coast of Central America to 14N93W to 1008 mb low near 14N99W to 08N118W. The ITCZ continues from 08N118W to 06N140W. Numerous moderate to strong convection within 75 nm of 12.5N99W. Scattered moderate isolated strong convection elsewhere from 08N to 15N between 93W and 105W. ...DISCUSSION... OFFSHORE WATERS WITHIN 250 NM OF MEXICO... Moderate to fresh northwest winds will persist west of the Baja Peninsula through Friday. Stronger northwest winds off the coast of southern California will enhance combined seas north of 29N between 120W and 125W to around 8 ft through tonight, then decay to 6-7 ft by Thursday afternoon. Gentle to moderate southerly winds are expected over the Gulf of California today. Seas will be 1 to 2 ft, except 3 to 4 ft over the entrance to the Gulf of California. Mainly light to gentle winds and 5 to 7 ft seas will continue south of Baja California. OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Moist southerly flow associated with the monsoon trough will continue to support scattered showers and thunderstorms mainly north of 04N. Some of this activity may contain strong gusty winds and produce rough seas. Light to gentle winds will prevail north of the trough axis with 4 to 6 ft seas. Mainly moderate south to southwest winds are expected south of the trough axis with seas of 5 to 7 ft. REMAINDER OF THE AREA... Broad high pressure covers the area north of 15N and west of about 115W. The pressure gradient between this ridge and lower pressure associated with the convergence zone is supporting fresh northeast trades from 07N to 15N west of 130W, with seas of 7 to 8 ft in mixed northeast and southeast swell. This area will gradually shrink through Thursday as the ridge retreats westward. Gentle to moderate trade winds will continue over the remainder of the forecast waters through today with 5-6 ft seas. $$ Mundell