Hawaii Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
345 AM EDT Sun Sep 10 2023

Valid 00Z Mon Sep 11 2023 - 00Z Mon Sep 18 2023

Today's guidance is fairly consistent and agreeable for the
expected pattern through next weekend.  Trades should strengthen
to moderate-brisk levels early-mid week as high pressure bridges
across the mid-latitude Pacific, while below-climatology
precipitable water values generally favor light rainfall totals
from showers favoring windward/mountain locations and occasionally
straying to a few leeward areas.  Trades will likely trend lighter
after midweek, first due to a cold front producing a break in
surface ridging to the north and then a surface trough (originally
associated with tropical cyclone Jova) moving through from east to
west during the weekend.  Upper ridging should prevail over the
islands for most of the week and then rapidly collapse after
Friday as shortwave energy descends from the north during the
weekend.  This energy could also help to weaken the surface
pressure gradient.  Meanwhile after midweek the guidance continues
to suggest that the trades will bring in pockets of greater
moisture, some having its origins with Jova, raising precipitable
water values to near or somewhat above normal.  Thus expect a
somewhat higher trend for rainfall late week into the weekend.

Rausch