AXPZ20 KNHC 280247

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0405 UTC Sun May 28 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 0215 UTC.


A tropical wave has an axis that extends from 06N92W to 15N93W, moving westward at 10 to 15 kt. Convection associated with this wave has diminished in coverage during the evening hours. Latest satellite imagery shows scattered moderate to isolated strong convection to the southeast of the axis from 04N to 07N between 90W and 92W. The wave remains under a broad inverted trough at 700 mb, and is embedded within a large area of very deep atmospheric moisture per latest TPW animation. Convection is expected to increase later tonight into Sunday morning with the wave. It is forecast to continue in a west to west-northwest motion through Monday.

A tropical wave has an axis that extends along 99W from 06N to 15N, moving westward at about 10 kt. The TPW animation depicts the wave to be embedded within an atmospheric environment of very deep moisture. Both model data and satellite water vapor suggest that a sharp 700 mb trough is located within the general vicinity of this wave. Latest satellite imagery shows scattered moderate to isolated strong convection from 06N to 10N between 96W and 100W, and also within 30 nm of a line from 09N99W to 10N101.5W.


The Monsoon Tough axis extends from far NW Colombia to 09N78W to 09N901. It resumes to the west of the western most tropical wave described above at a location near 09N101W to 09N110W. The ITCZ axis then begins at 09N110W, and continues to 08N130W to beyond 07N140W. Other than convection associated with the tropical waves described in the tropical waves section, scattered strong convection is within 45 nm of 09N86W. Scattered moderate to isolated strong convection is seen from 10N to 13N between 109W and 113W.



A trough extends from a 1007 mb low over far southeastern Nevada south to across the northern portion of the Gulf of California and to near 27N110W. Winds and seas have diminished over the northern portion of the Gulf have diminished, with seas down to around 2 ft and winds light and variable there. Gentle to moderate winds are expected over the Gulf the remainder of the weekend and into early next week. Low pressure will develop over the western United states during the middle portion of next eek, supporting moderate to fresh winds over the northern Gulf.

High pressure west of the region will support moderate to fresh northwest winds offshore Baja California the next several days with seas generally ranging from 5 to 7 ft. Elsewhere, mainly light to gentle winds are expected over the Mexico offshore waters south of Baja California through the middle of next week. The only exception to the winds will be along a pair of tropical waves that will pass along and south of the Tehuantepec area with associated scattered showers and thunderstorms along with brief gusty moderate to fresh east to southeast winds. A broad area of low pressure may develop to the southwest of southeastern Mexico and Gulf of Tehuantepec region during the middle portion of next week.


The Monsoon Trough will continue to intersect the region from west to east the next several days, supporting convection mainly north of around 03N. North of the trough axis mainly light to gentle winds will prevail with seas of 4 to 6 ft. To the south of the trough axis, moderate to locally fresh south to southwest winds can be expected with seas of 5 to 7 ft.


A weak ridge is forecast to meander over the northwestern waters near 30N133W over the weekend and into early next week which will continue to support gentle to moderate winds over the northern waters west of the Mexico offshore waters with seas of 5 to 7 ft. Moderate to fresh northeast to east winds prevail over the waters south of 20N, and also to the north of the ITCZ and Monsoon Trough. These winds will support seas of 6 to 7 ft. Another area of high pressure, a bit stronger, is forecast to build west over the northwest waters beginning on Tuesday. The pressure gradient between it and lower pressure near the ITCZ should allow for northeast trades to increase to 20 kt, with locally winds to 25 kt from 07N to 15N west of 130W. These winds should build the seas up to 8 to 9 ft there before winds diminish Wednesday. Seas are expected to linger up to 8 ft in mixed swell late Wednesday through Thursday night

$$ Aguirre