301 

FXHW01 KWNH 200715

PMDHI 



Hawaii Extended Forecast Discussion

NWS Weather Prediction Center College Park MD

315 AM EDT Wed May 20 2026



Valid 00Z Thu 21 May 2026 - 00Z Thu 28 May 2026



Broad high pressure anchored north of the Islands through the

forecast period will maintain moderate to occasionally strong E-NE

trades. Wind speeds will pick up early in the period, possibly

reaching advisory level in areas by Thu. Deep-tropospheric 

stability and seasonably dry airmass (PWAT values near 1.0-1.2") 

will persist as well, maintaining PoPs near climatological norms 

with the highly-predictable, spatial and diurnal distribution of 

fast-moving trade showers. PoPs will range from 30-60% over 

windward and mauka locations and generally less than 15% across 

leeward areas.



Hurley