AXPZ20 KNHC 240233

0405 UTC TUE MAY 24 2016

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.


The monsoon trough extends from 09N76W to 08N94W to 11N111W to low pres 1010 mb near 09N119W to 08N127W then ITCZ continuing on to low pres 1009 mb near 06N138W to beyond 05.5N140W. Widely scattered to scattered moderate to strong convection is from 05N- 11N between 80W and 110W. Widely scattered moderate to strong convection is within 150 nm of axis between 118W and 137W.


A surface trough extends from southern California to far north portions of Baja California Norte and the adjacent Gulf of California. Gentle to moderate W to SW winds are expected across the northern Gulf early tonight while variable light to gentle winds are expected across the southern Gulf. Global models continue to forecast a small area of low pressure developing across the northern Gulf tonight and persisting through Tuesday morning before dissipating, then redeveloping again Tuesday night. Southwest to south winds across the southeastern half of the low are expected to increase to 20 kt tonight and again tomorrow night, with seas building 4-5 ft.

Farther west, the persistent eastern Pacific ridge has weakened during the past 24 hours as a new cold front is moving southward to along 31N and approaching the northern boundary of the discussion area. The ridge now extends from a 1028 mb high center near 36N148W, southeastward over the remainder of the area to near 16.5N108W. The pressure gradient between the ridge and lower pressure across Baja California is producing moderate to fresh north-northwest winds across the near and offshore waters of the Baja Peninsula. The late afternoon and evening thermal contrast across the region is producing a fresh seabreeze across segments of the Pacific waters near the peninsula, where seas are running 6-7 ft, with small isolated areas to 8 ft. Winds and seas will diminish slightly later tonight as the peninsula quickly cools after sunset. The cold front will sink south into north portions of the waters during the next 24-36 hours and dissipate, with moderate high pressure sinking southward along 140W. This will maintain similar ridging across the area through Wednesday before the ridge strengthens modestly Wednesday night through Friday, which will act to freshen northwesterly winds along the Baja Peninsula.

The pressure gradient between the ridge and the monsoon trough to the south and southeast is promoting moderate to fresh trade winds generally south of 22N and west of 120W. Several weak and transient areas of low pressure are currently present along the monsoon trough, and forecast to continue along the monsoon trough through the week. Trade winds near these low centers may occasionally increase to fresh to strong across the northern portion, especially as convection flares up near the lows. Seas across this trade wind zone will remain 5-7 ft through Wednesday night before the ridge strengthens and winds and seas increase slightly to near 20 kt and 6-8 ft through Thursday.

S OF 15N E OF 110W...

Light to moderate winds are expected to continue across the forecast area south of the monsoon trough through the week, with light and variable winds north of the trough. Combined seas of 3 to 5 feet will prevail through Wednesday morning, and then will build to 4 to 7 feet for the remainder of the week as new cross- equatorial southwesterly swell arrives. Active convection is expected to continue about the monsoon trough through mid week.

$$ Stripling