NHC: Tropical Depression Likely to Form Southeast of Hawaii
The remnants of Tropical Depression Fifteen-E, located southeast of the Hawaiian Islands, are showing signs of organization and are forecast to develop into a tropical depression around midweek. There is a 60 percent chance of formation in 48 hours and a 90 percent chance within 7 days.
For the eastern and central North Pacific east of 180 longitude, the National Hurricane Center at 500 PM PDT Mon Sep 21 2026 is issuing advisories on Tropical Storm Odalys, well west-southwest of the southern tip of Baja California, and on Hurricane Polo, a few hundred miles south-southeast of Manzanillo, Mexico. Southeast of the Hawaiian Islands, the remnants of Former TD 15-E continue to generate showers and thunderstorms that are beginning to show signs of organization. Conditions are forecast to remain conducive for further development, and a tropical depression is likely to form around midweek as it moves slowly west-northwestward or northwestward.
Interests in the Hawaiian Islands should monitor the system. Formation chance through 48 hours is medium at 60 percent, and formation chance through 7 days is high at 90 percent. South of the Gulf of Tehuantepec, an area of low pressure could form in a few days. Thereafter, Environmental conditions appear favorable for gradual development, and a tropical depression could form late this week or this weekend as the system moves slowly west-northwestward to northwestward, parallel to the coast of southern and southwestern Mexico.
Formation chance through 48 hours is low, near 0 percent. Formation chance through 7 days is medium, at 50 percent.