May 28, 2026

The most notable weather event in the Pacific region this week is the magnitude 6.0 earthquake that struck the Island of Hawai'i on the evening of May 22. The earthquake was centered about 13 kilometers south of Hōnaunau-Nāpōʻopoʻo on the Big Island's west coast at a depth of approximately 23 kilometers. The U.S. Geological Survey (USGS) Hawaiian Volcano Observatory reported strong to very strong shaking on the west side of the island, with the potential for light to moderate infrastructure damage. Over 2,500 residents submitted felt reports to the USGS. Aftershocks have continued in the days since, though most have been below magnitude 3 and unlikely to be felt.

Across the mainland Pacific states, conditions are dry and warm. Arizona and Nevada are seeing above-average temperatures. California is dry with no active weather advisories. Strong trade winds are expected in Hawaii late this week into the weekend, with above-average wind speeds.

No active tropical cyclones in either the Eastern Pacific or Central Pacific basins.

The NIFC Southwest Coordination Center (SWCC) reports 4 active incidents across approximately 36,800 acres in the Southwest — the most active geographic area for wildfire in the country. Arizona and New Mexico are the primary areas of activity. Households in the wildland-urban interface across Arizona should be maintaining defensible space and monitoring local fire conditions.

In California, the California Department of Public Health (CDPH) issued an advisory on May 23 regarding a hazardous materials incident in Garden Grove involving the potential release of Methyl Methacrylate (MMA), a flammable and potentially toxic chemical. Mandatory evacuation orders were issued for the immediate area. Check with Orange County emergency management for current status if you're in the Garden Grove area.

Hawaii households in the area affected by the May 22 earthquake should report any structural damage to the County of Hawai'i Civil Defense Agency. Inspect your home for cracks in walls, foundations, and chimneys. If you notice damage, photograph it and keep records for potential insurance claims.

No broad public health advisories for the Pacific region. Air quality may be affected locally by wildfire smoke in parts of Arizona. The Garden Grove hazmat incident in California may affect air quality in the immediate vicinity — follow local evacuation guidance.

At the national level, the Centers for Disease Control and Prevention (CDC) has two active Health Advisory notices. The first, issued May 19, concerns an Ebola disease outbreak in the Democratic Republic of the Congo and Uganda caused by the Bundibugyo virus. The World Health Organization declared a Public Health Emergency of International Concern on May 17. The risk of spread to U.S. households is considered low. The second, updated May 18, monitors an Andes virus (hantavirus) cluster linked to a cruise ship in the Atlantic. No confirmed U.S. cases have been reported, and the domestic risk remains extremely low. Neither advisory requires household action beyond general awareness.

In Hawaii, no volcanic eruption is currently underway at Kīlauea or Mauna Loa. The Hawaiian Volcano Observatory continues to monitor all Hawaiian volcanoes for changes following the May 22 earthquake.

NOAA forecasts an above-average 2026 Eastern Pacific hurricane season, driven by the developing El Niño pattern. The agency predicts 15 to 22 named storms, 9 to 14 hurricanes, and 5 to 9 major hurricanes in the Eastern Pacific basin. An active Eastern Pacific could put Hawaii at increased risk of tropical systems this year. Hawaii households should review their hurricane preparedness plans.

Wildfire season is building across Arizona, California, and Nevada. The NIFC seasonal outlook projected above-normal fire risk for much of the Southwest. As temperatures rise and humidity drops, fire conditions will intensify through the summer.

Southern California earthquake clusters near Brawley (M4.7 and M4.5, May 9-10) and Santa Rosa (M4.4, May 7) earlier this month are reminders that seismic activity is a constant in the Pacific region. A M5.2 earthquake also struck near Reno, Nevada on May 1. Secure heavy items that could fall, know how to shut off your gas, and keep shoes near your bed.