AXPZ20 KNHC 060911

Tropical Weather Discussion
NWS National Hurricane Center Miami FL
1005 UTC Mon Jul 6 2020

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.


A broad low pressure system located several hundred miles south- southwest of the Gulf of Tehuantepec is producing a disorganized area of showers and thunderstorms. However, environmental conditions are expected to be conducive for development over the next several days, and a tropical depression is likely to form by the middle of the week while the system moves west-northwestward, well south of the coast of southern Mexico. This area of low pressure has a medium chance of becoming a tropical cyclone during the next 48 hours. Please, refer to the latest NHC Tropical Weather Outlook at www.hurricanes.gov for more details.

This system could bring an increase in winds and seas across the offshore waters of Mexico between Puerto Angel and Cabo Corrientes during the middle to latter part of the week. Looking ahead, global models have this system, possibly as tropical cyclone crossing near the Revillagigedo Islands toward the end of the work week, although predictions of potential track and intensity are uncertain at this time.


A tropical wave is analyzed along 98W north of 07N into southern Mexico, moving west at 10 to 15 kt. A 1009 mb low pressure is near the southern end of the wave axis at 09.5N98W. Scattered moderate isolated strong convection is noted from 09N to 14N between 95W and 102W.

A tropical wave is along 106W north of 07N, moving west at 10 kt. o Convection is limited near the wave axis.

A tropical wave is analyzed along 119W south of 20N, moving west at 10 kt. A stationary 1010 mb surface low is just east of the wave axis near 15N116W, along the monsoon trough. Scattered moderate convection is from 10N to 15N between 110W and 116W. Scattered moderate isolated strong convection is from 14N to 16N between 118W and 120W.


The monsoon trough extends from northern Colombia near 09N74W to 11N88W to 1009 mb low pressure near 09.5N98W to 1010 mb low pressure near 15N116W to 1010 mb low pressure near 12N124W to beyond 10N140W. A cluster of moderate to strong convection is noted N of the monsoon trough from 11N to 14N between 88W and 92W. This convective activity is affecting El Salvador and regional waters. Scattered moderate isolated strong convection can be found within 60-75 nm off the coast from western Panama to Nicaragua. Scattered moderate convection is seen from 10N to 15N between 120W and 130W, and from 08N to 10N between 134W and 137W.


Please see Special Features section for information on developing low pressure south-southwest of the Gulf of Tehuantepec region.

A ridge dominates the offshore forecast waters of Baja California producing mainly gentle to moderate NW-N winds. This weather pattern will persist through at least the middle of the week. A new swell event from the north will reach the forecast waters north of Punta Eugenia late today into tonight, building seas to 8-9 ft. This swell event will propagate across the waters north of Cabo San Lazaro through Wed with seas of 5-7 ft.

Expect fresh to locally strong southerly winds over the northern Gulf of California tonight through Wed as the pressure gradient tightens across the area between the ridge over the offshore waters of Baja California and lower pressures over the lower Colorado River Valley. Mainly gentle to moderate southerly winds are expected elsewhere across the Gulf of California.


Moderate to fresh NE-E winds are expected in and downstream of the Gulf of Papagayo during the next several days. Moderate to occasionally fresh SW winds will prevail over the waters south of 09N-10N E of 100W. Seas of 7-8 ft will persist over the offshore waters of Guatemala and El Salvador through Tue night in a mix of swell generated from the developing low pressure west of the area, and residual SW swell.


Please see Special Features section for information on developing low pressure south-southwest of the Gulf of Tehuantepec region.

A surface ridge dominates the waters north of 20N and west of 115W. As previously mentioned, a pair of low pressure areas are noted along the monsoon trough west of 110W. The eastern one located near 15N116W continues to produce a large area of disorganized showers and a few thunderstorms. Any development of this system should be slow to occur over the next couple of days while it moves slowly west-northwestward. The latest Tropical Weather Outlook states that this system has a low chance of tropical cyclone formation through 48 hours. The western one located near 12N124W is forecast to develop slightly into mid week. The most recent scatterometer data indicate the presence of these two low pressure areas.

The pressure gradient between the ridge and the aforementioned low pressure areas will support a large area of moderate to fresh trade winds north of the monsoon to about 20N between 115W and 130W. Moderate to locally fresh SW winds will also converge into the southern sides of lows south of the monsoon trough roughly between 110W and 125W.

Long period cross-equatorial S to SW swell dominates most of the forecast area. This will gradually subside over the next couple of days.

$$ GR