Cedar Mill, Oregon Weather Forecast Discussion

294
FXUS66 KPQR 021735 AAA
AFDPQR
Area Forecast Discussion...UPDATED
National Weather Service Portland OR
1034 AM PDT Thu Oct 2 2025
Updated short term discussion and aviation discussion.
.SYNOPSIS...Conditions will remain cool and showery today as
a low pressure system over the far northeast Pacific slowly moves
southward and weakens. Friday and Saturday will be seasonable along
with mainly dry conditions aside from a few stray showers. Low-level
offshore flow develops Sunday and continues into early next week,
bringing an extended period of dry weather with daytime high
temperatures in the 70s for most inland valley locations.
&&
.UPDATE...Thursday morning and afternoon...Radar and surface weather
observations from Thursday morning depicted a persistent slow-moving
band of light to moderate rain extending from COrvallis to Salem to
McMinnville to the greater Portland/Vancouver metro and Columbia
River Gorge/adjacent Cascade foothills. Hourly NBM PoPs are much too
low at 5-10% in these areas. Therefore, have updated the forecast to
increase PoPs significantly where rain is occurring and better
reflect current observations. Expect this band of rain to remain in
place through approximately 1 PM, before becoming more intermittent
and showery thereafter. -59
&&
.DISCUSSION...Now through Wednesday...The deep low which has
been the primary synoptic feature for our area over the past 72
hours will continue to impact the region. Models are in
excellent agreement that this low, current sitting just east of
Vancouver island, will continue to weaken as it slowly drifts
southward through the weekend. As this low meanders southward,
it will continue to send weak fronts over the Pac NW. This will keep
showers in the forecast. Expect an uptick in shower activity each
afternoon through Saturday, but with the Probability of
Precipitation (PoP) and rainfall totals continuing to decrease as
the weekend approaches.
Friday and Saturday, the forecast is trending mainly dry with
Sunday being dry as northerly flow aloft continues to develop
under a shortwave, upper level ridge. Also, temperatures will
become noticeably warmer Sunday through Tuesday as low-level
offshore develops. The NBM continues to suggest widespread
highs in the mid to upper 60s along the coast and low to upper
70s for inland locations. Current guidance is showing that
Tuesday will be the warmest from Sunday through Wednesday.
Lastly, overnight lows in the Upper Hood River Valley near the
Parkdale area will likely see morning lows today near 40
degrees and upper 30s on Friday morning. Cannot completely rule
out patchy frost Friday morning given the clear skies and light
winds, however the probability for this to occur is at 10-25%.
Probabilities drop to less than 5% in Odell and Hood River.
Given the marginal temperatures in place and the fact that
temperatures will most likely stay above 36-37 degrees, have
decided not to issue a Frost Advisory. However, given that this
is the growing season and October is upon us, the likelihood of
frost developing is increasing. /42-TK
&&
.AVIATION...Light to moderate rain over the Willamette Valley with
southwesterly winds. Winds are generally light, though periods of
isolated gusts with heavier bouts of rain. In general, VFR
conditions over the whole forecast area except in the central
Willamette Valley where conditions are bouncing between MVFR and
VFR. Have trended towards VFR as this will be the predominate CIG
level. Cannot rule out a period of reduced MVFR VIS with heavier
rain, but again, not expected to be widespread. Overnight, recent
hi-res models suggest around a 45-65% chance of MVFR CIG after 09Z
Fri along the coast with areas inland through the valleys of the
Cascades and lower I-5 corridor around KKLS. These CIGs will
likely be marginal. If clearing does occur before the sun sets,
there is a chance for radiational fog but those probabilities are
low.
KPDX AND APPROACHES...VFR conditions through the TAF period.
Moderate showers in the morning, easing through the afternoon. Less
than a 10% chance of MVFR CIGS/VIS, but will greatly depend on
clearing in the afternoon. -27
&&
.MARINE...A deep surface low pressure will linger west of Vancouver
Island and steadily weaken as it slowly moves inland through
Friday night. Winds will continue to subside through today,
falling below 15 kt by tonight. Seas remain elevated, but are
slowly subsiding and are expected to fall below 10 ft by Thursday
night. A Small Craft Advisory has replaced the Hazardous Seas
Warning and will persist through tonight. May see periodic
hazardous seas in the early afternoon, but will not be widespread.
High pressure rebuilds late in the week and through the weekend,
and will result in relatively benign winds and seas. -27/42
&&
.PQR WATCHES/WARNINGS/ADVISORIES...
OR...None.
WA...None.
PZ...Small Craft Advisory until 8 PM PDT this evening for PZZ210-
     251>253-271>273.
&&
$$
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NWS PQR Office Area Forecast Discussion