The National Hurricane Center gave a low-pressure area forecast to form south of the coast of Guatemala a 70 percent chance of becoming a tropical cyclone within seven days in its eastern Pacific outlook of Friday, Oct. 9, 2026. The chance within 48 hours was near zero, so the odds sit entirely in the middle of next week and after.
If it forms, the system would join Tropical Storm Rachel and Hurricane Simon, both already active in the basin on the same outlook.
The 70 Percent Figure in the Evening Outlook
The outlook issued at 5:00 PM PDT on Oct. 9 by forecaster Adams described an area of low pressure that is expected to form south of the Guatemalan coast early next week, moving generally west-northwest at about 10 mph. Formation chance through 48 hours was low, near 0 percent, and through seven days it was high, at 70 percent.
The same number appeared six hours earlier. The 11:00 AM PDT text outlook, written by forecaster Brown, carried the 70 percent figure, and its wording is a plain statement of timing: “An area of low pressure is forecast to form south of the coast of Guatemala early next week.” The outlook added that a tropical depression was likely by late next week. The earlier 5:00 AM PDT issuance had stood at 60 percent, a medium chance, so the odds rose by 10 points over the course of the day and then held through the evening update.
The center’s marine product for waters within 250 nautical miles of Central America reached the same conclusion. Its bulletin timed at 2205 UTC on Oct. 9 placed the low south of Guatemala early next week, a tropical depression by late next week and a high chance of tropical cyclone formation through seven days.
The center’s categories explain how much weight the figure carries. The center rates chances below 40 percent as low, 40 to 60 percent as medium and above 60 percent as high, so the area moved from medium to high between the morning and midday issuances and has stayed there. The outlook assigns the odds to a low that has not yet formed, and it names no storm until a tropical depression or tropical storm exists.
Tropical Storm Rachel and Hurricane Simon in the Same Basin
The new area would arrive while two named storms are still on the map. Intermediate Advisory 50A for Tropical Storm Rachel, issued at 11:00 AM PDT, put the storm near 23.1 degrees north, 124.5 degrees west, about 930 miles west of the southern tip of Baja California, with 50-mph winds, a pressure of 994 millibars and tropical storm watches for the Southern California coast and both coasts of Baja California.
Hurricane Simon, per Intermediate Advisory 10A, was a 110-mph hurricane about 190 miles south of Manzanillo, Mexico, under a hurricane warning from Punta San Telmo to Punta Mita.
The disturbance south of Guatemala sits in a different place from either storm. It is forecast to form near Central America, to the southeast of Simon’s position off Mexico’s west-central coast and far to the east of Rachel, which sits in the open ocean west of Baja California and has no connection to the new area beyond sharing the outlook map.
An El Niño Season in the Background
The season has unfolded under a strengthening El Niño. The Climate Prediction Center’s ENSO discussion of Oct. 8 kept the alert system at an El Niño Advisory and said a strong-to-very strong El Niño was likely through January-March 2027, with Niño-3.4 at +2.1 degrees Celsius and Niño-1+2 at +3.9 degrees. The discussion does not assign any single storm to that pattern, and the hurricane center’s outlook gives no such attribution either.
What the outlook does fix is the schedule. A low forming early next week, beginning around Monday, Oct. 12, and a tropical depression by late next week puts any resulting storm well past the 48-hour window in which the center currently shows nearly no chance, which is why the outlook rates the same area at near 0 percent for two days and 70 percent for seven. The gap between those two numbers is the forecast: nothing is expected to organize this weekend, and the odds build only after the low develops. The Atlantic side of the outlook, issued by forecaster Kelly at 8:00 AM EDT, listed no formation expected, so the Pacific outlook carried the only 7-day area on the page.
The next update to the 70 percent figure is the center’s following Tropical Weather Outlook. A move toward 90 percent, a drop back to the medium category or a low that forms ahead of schedule would each change the picture for the Pacific coast of Central America and southern Mexico, where Simon’s heavy rain is already forecast through Sunday.
This article was produced with the assistance of AI and reviewed by Morning Overview editors prior to publication.
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