AXPZ20 KNHC 262205

2205 UTC THU MAY 26 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 1800 UTC surface analysis and satellite imagery through 2145 UTC.


The monsoon trough axis extends from 09N84W to 07N92W to 10N105W to low pres near 10N115W 1012 mb to 08N124W. ITCZ axis extends from 08N124W to 08N138W. Scattered moderate to isolated strong convection is seen within 180 nm south of the axis between 95W and 100W, also between 101W and 105W, within 120 NM south of the axis between 86W and 88W and removed to the southeast of the convergence zone from 03N to 08N between 78W and 81W and within 30 nm of 13N106.5W. Scattered moderate convection is within 60 NM of the axis between 88W and 94W, and within 60 NM north of the axis between 117W and 122W.


High pressure centered well north of the area extends a ridge southeastward to 32N133W to 27N128W to 23N119W to near 20N110W. High pressure is present roughly north of 14N and west of 112W. Scatterometer data from last night showed fresh NE winds north of the convergence zone between 122W and 138W, with highest winds to 27 kt within 90 nm west of a trough axis analyzed from 12N136W to 08N139W. The trough is moving west about 15 kt. The trough and its associated winds and seas are forecast to move west of 140W by Fri morning.

Weak low pressure of 1012 mb is embedded along the monsoon trough near 10N115W. Latest satellite imagery shows that the low is elongated east to west in structure with small clusters of scattered moderate to isolated strong convection within 120 nm of low in the southeast quadrant and within 60 nm of the low in the northeast quadrant. Global model guidance suggests that the low will remain weak as it slowly moves west-northwestward through late Friday, then begin to become somewhat more organized late Friday into Saturday as it passes 120W. The strong high pressure north of the area is forecast to shift southwest over the next 48 hours while weakening.

Near gale to gale force NNW winds along the California coast are expected to produce an area of N swell that will sweep south of 32N Fri night and affect north-central waters N of 28N between 121W and 130W through Saturday. An area of seas to 8 feet in south swell located from 10N to 13N between 124W and 127W based on recent altimeter data is forecast to subside to just below 8 feet by early on Friday. Otherwise, rather benign marine conditions are expected to prevail across the remainder of the forecast area through Sun.

$$ Aguirre