FXUS66 KPQR 310533
AFDPQR

Area Forecast Discussion
National Weather Service Portland OR
1033 PM PDT Sat May 30 2026

.UPDATED AVIATION DISCUSSION...

&&

.SYNOPSIS...Dry conditions and seasonable temperatures with 
north to northwesterly winds expected through Sunday. A warming 
trend expected early next week, with Moderate HeatRisk likely on
Tuesday for many urban areas as there is around a 50% chance of
exceeding 90 degrees. Temperatures cool again to near or 
slightly above average by Wednesday as high pressure shifts 
east. Chances for rain remain low (less than 10%) through 
Thursday before increasing late next week into next Saturday.

&&

.SHORT TERM...Now through Tuesday night...Water vapor satellite 
imagery this afternoon reveals upper level troughing extending from 
the Gulf of Alaska into the Pacific Northwest. At the same time, 
surface high pressure remains strong over the NE Pacific centered 
well offshore off the northern CA coast, while lower level ridging 
maintains onshore northwesterly flow. This overall set-up for today 
will maintain seasonably cool and dry conditions with shallow 
cumulus this afternoon across the forecast area. With skies becoming 
mostly clear tonight, expect another round of cool temperatures 
overnight into early Sunday morning. Minimum temperatures in the 
Upper Hood River Valley near Parkdale are expected to be similar to 
last night, falling to around 36-38 degrees, while a few rural 
inland locations may also dip into the upper 30s, including northern 
Clark County, Coast Range valleys, including Vernonia and Grand 
Ronde, as well as pockets within the central and southern Willamette 
Valley. Confidence for widespread frost is low.  

Similar conditions into Sunday, except lower level flow turning more 
northerly as high pressure over the NE Pacific builds northward, 
allowing for slightly drier and warmer conditions across the area. 
With plenty of sunshine on Sunday, expect afternoon temperatures to 
increase around 3-6 degrees warmer than today, as the final day of 
May returns to seasonably average temperatures. Also expect diurnally 
induced northerly winds to become breezy by late afternoon, with 
gusts up to 25-30 mph along the coast and 20-25 mph inland. 

Will see warmer temperatures as the calendar changes to June. By 
Monday, upper level ridging attempts to amplify just offshore, while 
ensembles show the upper level troughing pinching off into a weak 
cut-off low over western Montana. This should keep the potential for 
the hottest temperatures at bay on Monday, but the warming trend is 
expected to continue into Tuesday. Light offshore flow develops 
early Monday while 850 mb temps warm to around 12-14C by Monday 
afternoon. Expect afternoon temperatures to jump into the lower to 
potentially mid-80s inland, while coastal locations may see high 
temps into the mid 60s to near 70 degrees, before the seabreeze 
moderates temps a bit. The latest NBM guidance continues to show ~5 
degree spread between the 25th and 75th percentile for the 
Portland/Vancouver metro (81-86F). There is around a 10-20% chance 
that some locations within the metro reach 90 degrees, including the 
Beaverton to Wilsonville corridor, as well as in the Clackamas area. 

Tuesday is still expected to be the warmest day this week as the 
upper low shifts northeast into Canada and upper shortwave ridging 
moves onshore across the PacNW. 850 mb temps peak at around 13-16C 
allowing for afternoon temperatures inland to warm into the mid-80s 
to potentially the lower-90s. Latest probs suggest there is around a 
40-60% chance of exceeding 90 degrees along the I-5 corridor from 
Castle Rock, WA south to Salem. A Moderate HeatRisk is likely (60-
80% chance) for Tuesday within the greater Portland/Vancouver Metro 
area, which means those without access to sufficient cooling and 
hydration may be impacted by the heat. Therefore, take precautions 
on Tuesday if participating in outdoor activities, especially during 
peak afternoon heating. The heat is not expected to last long, 
though as a decent marine push is expected by later Tue evening 
ahead of an upper shortwave trough. /DH

.LONG TERM...Wednesday through Saturday...There is relatively high 
confidence that temperatures cool back into the 70s on Wednesday and 
persist through the end of the week, remaining near to slightly 
above average temps for early June. Models and their ensembles are 
in fairly good agreement that a low pressure system in the NE 
Pacific weakens as it moves toward the Gulf of Alaska on Wednesday. 
An associated frontal band well ahead of the surface low will 
approach the coast, but guidance continues to trend down with much, 
if any, precipitation spreading inland. In fact, NBM guidance 
generally shows less than a 10% chance of rain through Thursday. 
But, there remain a handful of ensemble members that do show some 
QPF, so we cannot rule out some precipitation yet. Uncertainty in 
the forecast increases late next week as cluster mean analysis shows 
varying degrees of troughing offshore, leading to increasing chances 
for precipitation later Friday into Saturday. /DH  

&&

.AVIATION...VFR conditions generally persist tonight into Sunday
morning at all terminals as the flow aloft turns northerly.
However, we'll have to watch some low clouds shown by satellite
(as of 05-06z) building along the west flanks of the Cascades.
These have to potential to shift towards I-5/The Portland Metro 
during the 12-17z period Sunday morning before dissipating with a
15-25% chance for MVFR conditions at KPDX/KUAO and a 30-40% 
chance a KTTD. Otherwise, higher confidence in VFR conditions the 
remainder of the forecast period. Winds along the coast and in the
central/southern Willamette Valley increase as Sunday progresses 
with gusts around 20-25 knots possible. 

KPDX AND APPROACHES...VFR conditions are favored through the TAF 
period with persistent northwesterly winds. These winds likely
increase around 17-19z Sunday with occasional gusts around 18-20
knots in the afternoon. It's worth noting there is a 15-20% 
chance for MVFR cigs between 12-17z Sunday morning as clouds slosh
towards the terminal from the east - something to watch. -99

&&

.MARINE...High pressure builds through the weekend which will 
lead to a typical summer like pattern through the weekend. High 
pressure will start to move eastward tonight and through Sunday,
which will result in increasing north/northwesterly winds 
across all waters. Gusts up to 25 kt are expected across zones 
PZZ272, PZZ252, PZZ271 and PZZ251. Gusts up to 30 kt are 
expected in zones PZZ273 and PZZ253, with a 15-25% chance for 
gusts up to 35 kt. Therefore have issued a series of Small Craft
Advisories across all waters starting late Sunday morning in 
our southern waters and spreading northward through the early 
afternoon. Seas 6 to 8 ft expected through the weekend. 

The ridge continues to shift eastward and intensify through
Tuesday but overall will have minimal impact to the marine
environment. By Monday, conditions are expected to be below Small
Craft Advisory thresholds across all waters. A pattern change 
expected on Wednesday as a series of systems look to dive down out
of the northeastern Pacific through the latter part of next week,
but minimal impacts are expected with these systems at this time.
/42

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...None.
WA...None.
PZ...Small Craft Advisory from 2 PM Sunday to 2 AM PDT Monday for 
     PZZ251-252.
     Small Craft Advisory from 11 AM Sunday to 2 AM PDT Monday for 
     PZZ253.
     Small Craft Advisory from 5 PM Sunday to 2 AM PDT Monday for 
     PZZ271.
     Small Craft Advisory from 2 PM Sunday to 9 AM PDT Monday for 
     PZZ272.
     Small Craft Advisory from 11 AM Sunday to 9 AM PDT Monday for 
     PZZ273.
--------------------------------------------------------------------

FXUS66 KMFR 310506
AFDMFR

Area Forecast Discussion
National Weather Service Medford OR
1006 PM PDT Sat May 30 2026

...Updated Aviation Discussion...

.DISCUSSION...

Plenty of cumulus clouds are still around this afternoon as we
transition to a more zonal flow pattern with some short waves
traversing the forecast area. This will result in a low chance of
showers in northern California today. A thunderstorm is not out of
the question, although the probability is less than 10% based on
the latest HREF lightning probabilities. With a little more 
clearing tonight, temperatures should actually drop into the lower
40's west of the Cascades and lower 30's east of the Cascades. 
Those overnight low temperatures were warmer last night because of
the cloud cover, although that shouldn't be a problem tonight.

We'll begin the gradual warm up on Sunday as highs push about 5 
degrees warmer compared to today. No weather impacts are 
anticipated as high pressure begins to build.

By Sunday night, a short wave links up with another wave in the
northern Rockies and becomes briefly cutoff. We will see light 
east flow develop over the higher terrain Sunday night and that 
will warm us up further Monday into Tuesday. One could also 
analyze a weak thermal trough on Monday through Tuesday. 
Temperatures along the coast will warm notably on Monday with 
highs in the upper to mid 70's near Brookings.

By Wednesday afternoon or evening, another upper level wave will
arrive along the Oregon coast. Models are predicting spotty
showers and perhaps a few thunderstorms in the region. It looks 
like the best chances will be east of the Cascades Wednesday
afternoon. There is still variance in the ensemble forecasts, 
specifically the amount of precipitation. It's worth noting about 
15% of ENS ensemble members have no precipitation over all of 
Oregon on Wednesday, so it could still be a very dry day even with
this wave moving onshore.

Between Thursday and Saturday, the flow pattern looks zonal and
still very progressive with another trough arriving around 
Saturday evening of next week. The models look fairly wet and the 
PoP forecast is around 20 to 40 percent for the coast and areas 
around the Umpqua Valley. The PoP drops off notably farther to the
south and east during the day. The thunderstorm threat comes to 
mind Saturday afternoon and evening, although the convective
available potential energy(CAPE) looks fairly low on the 
ensembles. It will be something to watch in future forecasts.

&&

.AVIATION...31/06Z TAFs...VFR should prevail for most locations into 
Sunday morning, but some patchy IFR ceilings are possible in the 
Umpqua and Coquille Basins late tonight and early Sunday between 09-
16z. Saturday afternoon and evening, expect VFR conditions areawide. 
Afternoon/evening  breezes will be fairly typical, and strongest 
along the coast where peak winds in the 25-30 kt range are
expected. 

&&

.MARINE...Updated 1200 PM PDT Saturday, May 30, 2026...A thermal 
trough pattern will maintain gusty north winds and steep to very 
steep seas into Monday. For today, hazardous conditions are expected 
south of Cape Blanco, with very steep seas expected south of Pistol 
River. North winds will peak Sunday afternoon and evening, reaching 
gales from Gold Beach southward and beyond 2 nm from shore. This 
will also bring worsening conditions north of Cape Blanco, with 
conditions hazardous to small craft expected for all areas and very 
steep seas expected from Bandon southward. 

Winds ease some Sunday night and even moreso on Monday, but steep to 
very steep seas are likely to continue through Monday. Conditions 
improve for all areas by Tuesday as the thermal trough pushes inland 
and north winds weaken below advisory levels. Below advisory 
conditions likely persist through the remainder of the week with a 
low west-northwest persistent swell. /BR-y

&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...CA...None.

PACIFIC COASTAL WATERS...Small Craft Advisory until 11 PM PDT Sunday 
     for PZZ356. 

Small Craft Advisory from 11 AM to 11 PM PDT Sunday for PZZ350-
     370. 

     Hazardous Seas Warning until 11 AM PDT Sunday for PZZ356-370-
     376. 

     Gale Warning from 11 AM to 11 PM PDT Sunday for PZZ356-376. 

     Small Craft Advisory until 11 AM PDT Sunday for PZZ376. 

--------------------------------------------------------------------

FXUS66 KPDT 310444
AFDPDT

Area Forecast Discussion
National Weather Service Pendleton OR
944 PM PDT Sat May 30 2026

.KEY MESSAGES...
- Warming temperatures through midweek.

- Dry conditions for much of the week, with the potential for
  mainly mountain showers and thunderstorms around midweek.

&&

.DISCUSSION...
A more zonal flow is expected to develop over the region as an
upper low over the northern Rockies moves northeast. By Sunday,
a weak upper low will move over the area, but is expected to be
dry. This low will then help carve out a broader trough that 
will shift eastward with the upper low moving to northern 
Montana/southern Canada by Monday night. Can't rule out a 
passing shower with the low, especially over the mountains, but 
overall chances are low (<20 percent). 

As this low spins to the northeast, weak ridging will build in
for Tuesday. A weak trough and some shortwave energy will then
move across the region Wednesday into Thursday. With this
feature will come the best chances for precipitation and
thunderstorms in the next 7 days. Thunderstorm chances, although
low (<20 percent) look to be highest over the mountains of
central and eastern Oregon).   

Dry and a bit cooler weather returns for Thursday and Friday. 
By Saturday, precipitation may start to return, especially to 
the Cascades as an upper low off the coast approaches the 
region. There is still some uncertainty with the timing of this 
system, and we are a week away but it will bear watching. 
Additionally, depending on the track and timing, winds may begin
to increase as early as Friday, or into Saturday across 
portions of the area.

&&

.AVIATION /06Z TAFS THROUGH 06Z MONDAY/...

Regional satellite imagery showed clear sky other than some 
high level thin clouds over PSC/ALW/PDT, with no impacts to 
terminals. Breezy winds with gusts around 20 knots will continue
though around 10z at YKM and DLS, but are expected to be below 
12 knots elsewhere. 


&&

.Preliminary Point Temps/PoPs...
PDT  42  71  45  76 /   0   0   0   0 
ALW  47  72  50  76 /   0   0   0   0 
PSC  43  77  48  80 /   0   0   0   0 
YKM  42  77  48  80 /   0   0   0   0 
HRI  43  75  47  79 /   0   0   0   0 
ELN  39  71  45  75 /   0   0   0   0 
RDM  29  67  34  73 /   0   0   0   0 
LGD  37  68  41  72 /   0   0   0   0 
GCD  34  70  37  75 /   0   0   0   0 
DLS  45  76  49  83 /   0   0   0   0 

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
WA...None.
OR...None.

--------------------------------------------------------------------

FXUS65 KBOI 310517
AFDBOI

Area Forecast Discussion
National Weather Service Boise ID
1117 PM MDT Sat May 30 2026

.UPDATE...Updated aviation discussion.

&&

.KEY MESSAGES...
- Slightly warmer Sunday, but continued cool and drier with
  breezy conditions across the Magic Valley area.

- Temperatures warming to around 5-10 degrees above normal next
  week.

- Breezy Wednesday and Thursday with a 20-40% chance of showers
  and thunderstorms across the north.

&&

.SHORT TERM /Through Monday Night/...
Issued 219 PM MDT SAT MAY 30 2026
An upper low centered over western Wyoming will move north into 
Montana tonight and Sunday, then merge with a trough over the 
Pacific Northwest on Monday. The main impact from the low will 
be breezy west-northwest winds through early this evening and 
again on Sunday, although winds aren't expected to be as strong 
Sunday. Winds will subside on Monday. Most areas will be dry as 
the low pulls away, except the eastern half of Valley County and
headwaters of the Boise River Basin which will see a 20-50% 
chance of showers and embedded thunderstorms late this afternoon
and a 20-30% chance on Monday. It will remain cool the rest of 
the weekend but high temperatures will trend up 1-3 on Sunday, 
then around 5 more degrees on Monday. Low temperatures will be 
cool through the period, with 40s in the lower valleys and 30s 
in the mountains.

&&

.LONG TERM /Tuesday through Saturday/...
Issued 219 PM MDT SAT MAY 30 2026
Temperatures will continue to rise Tuesday and Wednesday from
high pressure building in aloft from upper-level shortwave 
ridging. This will be short lived, as another upper-level 
shortwave trough will move through Wednesday afternoon into 
Thursday afternoon. The potent area of this trough is favored to
move across our northern areas, bringing a 20-40% chance of 
showers and thunderstorms to Baker County and the west-central 
Idaho mountains. Elsewhere, precipitation chances will be lower.
Breezy conditions will develop across the area with the passage
of the trough. Highs are forecast to warm a few degrees before 
the arrival of the trough, reaching 5-10 degrees above normal. 
Temperatures will cool slightly (back to near-normal temps) 
Thursday behind the trough. 

On Friday, significant cluster disagreement exists for an
incoming intense upper-level low moving down the Pacific NW 
coast. GEFS members cluster around stronger southwest flow 
aloft, while the EC ensemble is closer to zonal/weaker southwest
flow. Regardless of the solution, warmer temperatures and 
continued breezy conditions are expected. This trough is 
expected to move inland over the weekend, although there are 
similarly timing and strength differences between ensemble 
members. For now, the forecast trends cooler on Saturday with a 
10-20% chance of showers across the north.

&&

.AVIATION /06Z Sunday through Monday/...
Issued 1113 PM MDT SAT MAY 30 2026

Mainly VFR. Areas of mountain obscuration NE of KMYL and patchy 
mountain fog overnight. Surface winds: W-NW 5-15kt with gusts to 
25kt near KJER KTWF Sun afternoon. Winds aloft at 10kft MSL: 
W-NW 20-30kt easing to 10-20 kt Sun afternoon.

KBOI...VFR. Surface winds: NW 5-10kt, gusts to 20kt during the 
afternoon.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...None.

OR...None.

--------------------------------------------------------------------

FXUS66 KSEW 310243
AFDSEW

Area Forecast Discussion
National Weather Service Seattle WA
743 PM PDT Sat May 30 2026

.SYNOPSIS...
An upper level ridge will slowly build across the
Pacific Northwest this weekend, resulting in a gradual warming
trend into early next week. Temperatures will peak on Tuesday,
resulting in Minor to Moderate HeatRisk. Onshore flow will
increase Wednesday with upper troughing approaching Western
Washington late in the week.

&&

.SHORT TERM /TONIGHT THROUGH MONDAY NIGHT/...
No evening updates for the short/long term discussions. -HPR

A mix of clouds and sunshine this afternoon with continued weak
onshore flow across Western Washington. Temperatures remain 
relatively cool today, with highs in the upper 50s to mid 60s. 

Upper level ridging will gradual build into Western Washington
beginning Sunday and continuing into early next week. This will
result in a warming trend across the area. Highs on Sunday will
peak in the 60s to low 70s, with Monday afternoon temperatures
reaching the 70s, with low 80s south of Olympia and near
interior Grays Harbor County. An upper level low located over
Montana on Monday will also spread high clouds into Western
Washington, particularly during the afternoon.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
The upper ridge will
remain situated over Western Washington on Tuesday before the
ridge begins to flatten midweek. A brief thermal trough will
build into the region on Tuesday, which results in Tuesday being
the warmest day of the week with light offshore flow. 
Widespread highs in the upper 70s to mid 80s are expected. The 
potential for low 90s Tuesday afternoon will also exist from 
Olympia southwards and into interior Grays Harbor and Mason 
Counties. Widespread Minor to Moderate HeatRisk will exist on 
Tuesday. Despite the warm air temperatures, rivers and lakes 
remain cold. If you're heading out on the water, always wear a 
life jacket and take precautions for the cold water. In addition
to the warm temperatures, daytime RH values will dip between 20
to 30% with light east flow - see fire weather section for more
details. 

Ensembles are generally consistent in the upper ridge slowly
flattening by Wednesday, resulting in increasing onshore flow.
Temperatures will cool by midweek, with forecast high
temperatures on Wednesday in the 60s and 70s. Onshore flow will
continue on Thursday. Ensembles begin to show a deeper trough
developing across British Columbia by late next week into the
following weekend. There is a notable uptick in POPs by late
Friday into Saturday with the upper troughing, in addition to
cooler temperatures next weekend. JD

&&

.AVIATION... 
Upper level troughing over the northeastern Pacific will maintain 
southwesterly flow aloft tonight before becoming more westerly by 
early Sunday morning. Northwesterly flow aloft is expected to be in 
place by Sunday afternoon as an upper level ridge starts to build 
offshore. Onshore flow continues in the low levels with surface 
winds speeds generally ranging 5-10 kts for the TAF period. 

VFR conditions in place over W WA this early evening and while there 
may be some increase in mid-level cloudiness in some spots tonight 
and early Sunday morning, cloud bases expected to remain well within 
VFR thresholds with minimal impact to terminals expected. Any 
increase in cloud cover will diminish into the day Sunday as upper 
level ridging becomes a greater influence over the area.

KSEA...VFR conditions with scattered clouds between 6000-7000 ft for 
the TAF period.Some additional cloudiness possible at the terminal 
Sunday morning before clearing again by afternoon. Northerly winds 5-
10 kt for the period, although speeds in the overnight and early 
morning hours are more likely to inhabit the lower end of that 
range. North to northwesterly winds increase to 8-12 kt Sunday 
afternoon.

14/18


&&

.MARINE...
Small craft advisory strength westerlies will persist across 
the central and eastern Strait of Juan de Fuca tonight into 
early Sunday morning before easing. The increased onshore flow 
will also bring gusty northwesterly winds to 25 kt to Admiralty 
Inlet at times tonight. Winds will then ease across the majority
of the area waters on Sunday as high pressure builds across the
coastal waters, though portions of the coastal waters will see 
an increase of northwesterly winds which could approach small 
craft criteria at times Sunday afternoon and evening. This 
pattern will also allow for waves to rise and steepen to 7-9 ft  
at a period of around 7-9 seconds. Winds will gradually ease 
and waves will subside towards 5-7 ft heading into Monday as 
high pressure weakens over the region. A thermal trough then 
looks to develop along the coast Monday night into Tuesday, 
which will bring a brief period of offshore flow to the area 
waters- but will not be strong enough to have any significant 
marine impacts.

A frontal system will then move across the area waters
Wednesday into Thursday, resulting in the return of onshore 
flow. Additional headlines will be likely for the central and
eastern Strait of Juan de Fuca as onshore flow increases 
Wednesday night. Seas will primarily range between 6-8 ft.

14 

&&

.FIRE WEATHER...
An upper ridge will result in a drier pattern
Monday and Tuesday with maximum temperatures reaching the 80s
(and a few spots in the low 90s) by Tuesday. Light offshore flow
is expected late Monday into Tuesday as a brief thermal trough 
develops. At this time, winds are not expected to be strong,
however, a few locations within the Cascades could see gusts in
excess of 20 MPH. In addition, minimum RH values will lower 
into the 20 to 35 percent range for most locations away from the
water. However, this stretch of warm, dry conditions will be
short-lived as onshore flow resumes by Wednesday bringing higher
RHs for the second half of the week.

&&

.HYDROLOGY...
The daily hydrology discussion has ended until the
start of the next rainy season; it will only be updated during 
this time as needed.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...Small Craft Advisory until 7 AM PDT Sunday for Central U.S. 
     Waters Strait Of Juan De Fuca-East Entrance U.S. Waters 
     Strait Of Juan De Fuca.

     Small Craft Advisory until 5 AM PDT Sunday for Admiralty Inlet.

--------------------------------------------------------------------