Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
355 AM EDT Sat Mar 14 2026

Valid 00Z Sun 15 Mar 2026 - 00Z Sun 22 Mar 2026

...Powerful Kona Storm to begin to weaken, but heavy rain and 
flash flood threat will continue over the next week...

The high-impact and life-threatening Kona Storm pattern will 
continue across Hawaii through the weekend as this storm remains 
centered near approximately 35N and 165-170W. Model consensus is 
for this storm to begin to weaken by Monday as the associated mid 
to upper level trof becomes more elongated and sheared in a west 
to east direction. However, this will not affect the placement of 
an axis of very anomalous PW values to the southeast of the low, 
with values 2 to 4+ standard deviations above the mean, remaining 
centered across the Islands through much of the upcoming week.

There is some model consensus that for the day 1 and day 2 
periods, 0000 UTC Sun Mar 15 to 0000 UTC Mon Mar 16 and 0000 UTC 
Mon Mar 16 to 0000 UTC Tue Mar 17, that the axis of the greatest 
PW anomalies will be centered more over the eastern portion of 
the state from Maui to the Big Island. Subsequently, consensus is
for the heaviest rains these days across these islands, with less
westward across the remainder of the islands.

After this, with the weakening trend to the upper and surface low
to the northwest of the island, the forecast model precip axes
diverge more, leading to low confidence in details. However, with
agreement that the anomalous PW axis will remain across the
islands, and expand back to the west across the remaining islands,
there is greater confidence for additional heavy rains extending 
into mid to late week.

With soils already saturated from recent heavy rains, the multi 
day threat of heavy rains will support the continued risk of
life-threatening flash flooding statewide into all of next week


Oravec