When Is Flu Season in Hawaii?

The Short Answer

Flu circulates year-round in Hawaii. The Hawaii Department of Health says influenza is most common during fall and winter and that activity usually begins to increase in October. Hawaii can also have meaningful flu activity outside the mainland’s usual winter peak.

For the current weekly signal—not just the typical calendar pattern—open the Hawaii flu dashboard.

What Months Are Flu Season in Hawaii?

There is no single start-and-stop month that captures every Hawaii flu season. A practical way to think about it is:

• Flu can spread in any month. Hawaii health officials describe influenza as circulating year-round.
• Fall and winter are the more common high-activity period. Hawaii activity usually starts rising in October, but the exact timing and height of the peak can change.
• Hawaii does not always mirror the mainland. The state’s influenza surveillance program notes that Hawaii’s peak can differ from the continental United States and that islands can show different patterns.

Across the United States, the CDC describes flu season as primarily fall and winter, with activity most often peaking between December and February. That national pattern is useful context, but it should not replace Hawaii’s own surveillance.

Is Flu Going Around Hawaii Right Now?

The answer changes week to week. The Hawaii flu activity page shows the latest available CDC FluView/ILINet signal, including:

• the share of participating outpatient visits that meet the influenza-like-illness definition;
• whether that signal is rising, falling, or stable;
• how Hawaii compares with the national signal; and
• a trend chart that puts the latest week in context.

ILI surveillance is an early public-health signal, not a count of laboratory-confirmed flu cases and not a diagnosis. Reporting can also vary from week to week, so read the date and trend together rather than relying on one number.

Planning a Trip to Hawaii

Because flu can circulate year-round in tropical destinations, the CDC’s travel guidance recommends considering influenza risk even outside the usual mainland season. Use the Travel Health Check for a destination overview, and consult a healthcare professional for personal vaccination or treatment decisions.

Other Health Data for Hawaii

• What’s going around in Hawaii? — statewide overview
• Hawaii COVID-19 activity — weekly hospital-admission signal
• Hawaii RSV activity — weekly hospital-admission signal
• Hawaii measles cases — current national and approximate state context
• Hawaii MMR vaccination rate — Kindergarten coverage