Tropical Weather Discussion

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Tropical Weather Discussion NWS National Hurricane Center Miami FL 1005 UTC Mon Jul 13 2026 Tropical Weather Discussion for the eastern Pacific Ocean from 03.4S to 30N, east of 120W including the Gulf of California, and from the Equator to 30N, between 120W and 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 0700 UTC. ...SPECIAL FEATURES... Offshore of Southwestern Mexico: A tropical wave is producing a large area of disorganized thunderstorms and gusty winds a couple of hundred nautical miles south of the coast of southern Mexico as described with the monsoon trough below. Currently, winds are 20 to 25 kt with this system, along with seas of to 8 ft. Environmental conditions appear favorable for continued gradual development, and a tropical depression is expected to form in the next 2 or 3 days while the system moves generally west- northwestward, well off the coast of Mexico. The latest Tropical Weather Outlook gives this system a medium chance of tropical cyclone formation in the next 48 hours, and a high chance through 7 days. Please read the latest Tropical Weather Outlook issued by the National Hurricane Center at www.hurricanes.gov for further details. ...TROPICAL WAVES... The axis of a tropical wave is near 79W, and extends from near the NW border of Colombia and Ecuador at 02N northward to near the Panama Canal and into the Caribbean Sea, moving westward at around 15 to 20 kt. Any nearby convection is described below in the ITCZ/monsoon trough section. The axis of a tropical wave is near 99.5W, from 04N northward over portions of southern and SW Mexico, moving westward at around 10 to 15 kt. Any nearby convection is described below in the ITCZ/monsoon trough section, with additional details also in the Special Features section regarding the potential for tropical cyclone formation. The axis of a tropical wave is along 133W from 04N to 19N, moving westward at around 10 kt. A 1008 mb low pressure is analyzed along the wave axis near 15N132W. Any nearby convection is described below in the ITCZ/monsoon trough section. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... The monsoon trough extends from 11N74W to 10N86W to 09N94W. The ITCZ extends from 09N94W to 09N98.5W, then resumes west of a tropical wave from 09N101W to 04N119W to 12N131W. Another monsoon trough segment extends from 12.5N133.5W to 08N140W. Scattered moderate isolated strong convection is noted from 05N to 09N between 77W and 83W, within 300 nm either side of the ITCZ between 95W and 114W, and from 12N to 17N between 128W and 132W. Similar convection is found within 120 nm of the coast between 87W and 95W. Scattered moderate convection is noted from 06N to 12N between 133W and 140W. ...OFFSHORE WATERS WITHIN 250 NM OF MEXICO... A ridge dominates the offshore forecast waters of Baja California supporting gentle to moderate winds per recent ASCAT scatterometer data, with moderate seas observed by a pair of recent altimeter passes, in mixed swell. Light to gentle winds are in the Gulf of California where slight seas prevail. Moderate to increasing northerly winds are blowing in the Gulf of Tehuantepec with moderate seas. An area of fresh to strong winds extends from the coast of Oaxaca to about 11N between 96W and 101W along with mainly rough seas. Over the remainder of the Mexican offshore waters, winds are gentle to moderate from the NW and seas are generally moderate, primarily in SW swell. Active convection is present offshore of the majority of southern and SW Mexico as described above. For the forecast, a tropical wave is producing a large area of disorganized thunderstorms and gusty winds a couple of hundred nautical miles south of the coast of southern Mexico. Please, see the Special Features section for more details. A ridge will continue to dominate the offshore forecast waters of Baja California through early Thu, allowing for gentle to moderate NW to N winds to continue along with moderate seas in mixed swell. In the Gulf of California, mainly gentle winds will prevail through Tue night, increasing to moderate to locally fresh in the central and northern portions midweek. Fresh to strong northerly winds will pulse in the Gulf of Tehuantepec during the week, strongest during the late night and early morning hours, with locally rough seas at times. ....OFFSHORE WATERS WITHIN 250 NM OF CENTRAL AMERICA, COLOMBIA, AND WITHIN 750 NM OF ECUADOR... Fresh easterly winds in the Papagayo region observed by an earlier ASCAT pass have likely increased to fresh to strong in the past few hours, with moderate to fresh easterly winds elsewhere from 10N to 12N. Winds are light to gentle across the remainder of the waters per ASCAT and OSCAT scatterometer passes. Moderate seas dominate the waters. Areas of convection associated with the monsoon trough are described above with locally higher winds and seas. For the forecast, fresh to strong gap winds will prevail in the Papagayo region mainly at night through at least Fri night along with moderate to locally rough seas. Fresh to locally strong winds and rough seas are forecast to impact the offshore waters of El Salvador and Guatemala today due to the departing presence of a tropical wave several hundred nautical miles south of the coast of southern Mexico. Moderate or weaker winds and moderate seas in SW swell will prevail elsewhere, except in the lee of the Galapagos Islands where slight seas are expected. ...REMAINDER OF THE AREA... A surface ridge prevails across the waters N of 20N W of 110W. Under the influence of the ridge, mainly moderate or weaker winds are observed by recent ASCAT scatterometer passes, with moderate seas in mixed swell. South of 20N, there are two tropical waves and a surface trough. The surface trough runs from 21N121W to 09N121W, while the tropical waves are near 99.5W and 132W as mentioned above. Any associated convection is described above. A 1008 mb low pressure area analyzed on the tropical wave near 132W is supporting locally fresh winds and locally rough seas within about 150 nm in the northern semicircle. Moderate or weaker winds are elsewhere, locally fresh south of the ITCZ between 97W and 120W, along with moderate seas. For the forecast, the National Hurricane Center (NHC) is monitoring several areas with the potential for tropical cyclone development across the eastern and central Pacific. Three of those disturbances are located in the eastern Pacific region. One is a tropical wave a couple of hundred miles south of the coast of southern Mexico. Please, see the Special Features section for more details. The second area is an area of low pressure located well west-southwest of the Baja California Peninsula, which continues to produce disorganized showers and thunderstorms, primarily east of its center. This system is expected to move west-northwestward into less favorable environmental conditions during the next couple of days, and its development chances appear to be decreasing with a low chance of tropical cyclone formation in the next 48 hours, and also through 7 days. Finally, an area of low pressure is expected to form by the middle of the week several hundred nautical miles south of the coast of southern Mexico. Environmental conditions appear conducive for gradual development of this system thereafter, and a tropical depression could form by the end of the week or next weekend while it moves generally west-northwestward well offshore of Mexico. This system has a low chance of tropical cyclone formation through 48 hours and a medium chance through 7 days. Otherwise, expect little change except for freshening winds in the northwestern open waters by the end of the week as the pressure gradient tightens, resulting in building seas to rough.