Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
317 AM EDT Sat Apr 19 2025

Valid 00Z Sun 20 Apr 2025 - 00Z Sun 27 Apr 2025

Models and ensembles again seem reasonably well clustered, 
bolstering forecast confidence in a favored composite solution 
that again should tend to mitigate lingering smaller scale 
variances consistent with individual predictability. An upper 
trough lingering atop Hawaii will slowly lose influence today 
along with trade disrupting inverted troughing. Winter weather 
advisories for the Big Island summits linger in the short term. 
For the weekend, the upper trough is forecast to further weaken 
and slowly shift away to the east, while Pacific surface high 
pressure develops/bridges well to the north of the state and allow
trades to gradually increase. Expect a generally wet trade 
pattern through early next week as fueled by lingering moisture. 
Then from around the middle to later next week, another upper 
trough and possible closed low is forecast to dig just to the west
of the state. This will once again cause the mean flow to veer 
for southeasterly/southerly winds that may be stronger this round
so there is potential for moisture and showers to again increase.

Schichtel