Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
111 AM EDT Mon Sep 14 2026

Valid 00Z Tue 15 Sep 2026 - 00Z Tue 22 Sep 2026

A tranquil pattern will linger through the first half of the weak
with light trade winds modest moisture aloft. By mid-week, the
pressure gradient begins to tighten and trades look to increase,
at the same time as Norbert's remnants approach Big Island and
Maui. PWs by Wednesday night and into both Thursday and Friday 
rise to as high as +2.0 standard deviations above normal, and the 
increase in trades will support stronger upslope enhancement. This
will result in an unsettled second half of the week with numerous
showers and locally heavy rainfall in the mountains. By the 
weekend, the bulk of Nortbert's remnants will exit to the west 
and, while some lingering moisture content will still be present, 
trades will decreases slightly and reduce the coverage of showers 
for the weekend. Only typical windward facing elevations would 
likely contend with occasional showers. 

Focus will then shift to the status of newly formed Tropical 
Depression Fifteen-E, as its anomalous moisture source could make 
its way into the central Pacific early next week.

Mullinax