AXPZ20 KNHC 301527

1005 UTC MON MAY 30 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 1200 UTC surface analysis and satellite imagery through 1500 UTC.


A tropical wave along 91W south of 14N is moving westward at 15 kt. Scattered moderate isolated strong convection is within 240 nm east of the wave axis from 07N to 13N between 87W and 91W. The surface pressure gradient near the wave is forecast to become weaker during the next 36-48 hours as the wave becomes more diffuse.

A tropical wave along 77W-78W south of 15N is moving westward at 10-15 kt. The wave will cross Panama and move into the eastern Pacific this evening.


The monsoon trough extends from 10N93W to low pres near 09N107W 1010 mb to 14N117W to low pres near 14N120W to 09N127W, then ITCZ from 09N127W to beyond 08N140W. Scattered moderate isolated strong convection from 07N to 11N between 108W and 113W.


The subtropical ridge prevails over northern waters N of 17N and west of 115W. Cold front NW of the area from 36N144W to 27N148W is being blocked by high pressure north of the area, and is expected to become stationary west of 140W during the next 36-48 hours. A persistent low pressure area near 14N120W is nearly stationary, and scatterometer data showed 20 kt winds near the circulation center. The low is expected to weaken and transition to a trough during the next 24-48 hours. Convection associated with the low has been spotty and unorganized during the past 24 hours. Scatterometer data from last night indicates gentle trade winds over most of the area north of the convergence zone, and mainly light southerly winds to the south. Model guidance shows multiple weak transitory cyclonic circulations embedded in the monsoon trough the next few days, with little possible tropical development expected until late this week - based on the ECMWF.

$$ Mundell