Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
357 AM EDT Tue May 17 2022

Valid 00Z Wed May 18 2022 - 00Z Wed May 25 2022

The latest guidance continues to show good agreement on a central
Pacific upper trough with embedded low approaching Hawaii early
this week. Winds will shift to a more south/southeasterly
direction, helping to advect a significant increase of moisture
towards the state ahead of the attendant cold front. More
widespread and heavier rainfall is becoming increasingly likely
across Kauai and western islands around Wednesday to Friday as the
cold front could linger for a few days causing possible localized
flooding concerns as well. Details regarding amounts and intensity
remain uncertain and highly dependent on exactly where the cold
front sets up with the GFS continuing to show a slightly farther
east placement and heavier rainfall over Kauai. Elsewhere across
the main islands, the increased moisture should result in mainly
scattered showers and typical sea breeze enhancements. By the end
of this week and into the weekend, the trough will begin to lift
out and upper ridging once again builds across the region with
more typical breezy easterly trades resuming and lasting into
early next week.

Santorelli