FXUS66 KPQR 152115
AFDPQR

Area Forecast Discussion
National Weather Service Portland OR
215 PM PDT Wed Apr 15 2026

.SYNOPSIS...Post-frontal rain and mountain snow showers continue
but will decrease coverage through Thursday night. Any heavier
shower may produce small hail, while there is also a 15-30% 
chance of isolated thunderstorms this afternoon and evening. 
Accumulating snow continues above 2500 feet and Winter Storm 
Warnings remain in effect in the Cascades through tonight. The 
cooler airmass will also favor frost/freeze conditions tonight 
and possibly Thursday night.

&&

.SHORT TERM...Now through Friday Night...The potent cold front
which crossed the region last night through this morning has
exited the region to the south and east. Behind the front, 
scattered to numerous rain and mountain snow showers will linger
into Thursday as a closed upper-level low passes overhead. With
the cold core low aloft, any surface heating during sun breaks 
between showers will easily destabilize the column, generating 
perhaps 200-500 J/kg of SBCAPE. When combined with low freezing 
levels around 2500 ft, even a heavy shower could result in small
hail reaching the surface. There is additionally a 15-30% 
chance of isolated thunderstorms this afternoon and evening, 
although limited instability will cap overall thunderstorm 
intensity. These chances will decrease after sunset, but may 
linger later into the evening as the coldest air within the 
upper low shifts overhead. Meanwhile in the Cascades above 2500 
ft, snow showers will continue to produce accumulating snowfall.
Winter Storm Warnings remain in effect until 5 AM Thursday as 
another 9-12 inches of snow may fall, resulting in storm total 
accumulations of 1-2 feet at and above pass level.

As the upper low exits eastward and heights begin to rise aloft, 
rain showers will tend to dwindle in coverage tonight through 
Thursday and the cooler air mass will see temperatures fall to 
near-freezing across portions of the region. Despite morning 
low temperatures of 32-36 degrees across the lower elevations of
NW Oregon and SW Washington, the combination of partly cloudy 
skies and persistent light winds tonight may inhibit widespread 
frost formation. Frost Advisories nonetheless remain in effect 
from 1-9 AM Thursday west of the Cascades with the exception of 
the immediate coast, Portland/Vancouver metro, and Columbia 
Gorge where temperatures will remain relatively warmer. East of 
the Cascade crest in the Upper Hood River Valley, temperatures 
will more likely fall into the upper 20s to low 30s, and a 
Freeze Warning has therefore been issued for 1-9 AM Thursday. 
Agricultural interests and those with sensitive outdoor plants 
should plan to take protective action to prevent plant damage. 
Conditions will be even more supportive of radiational cooling 
on Thursday night, however the slowly moderating air mass may 
counteract that tendency. A Freeze Watch has been issued from 
1-9 AM Friday for the areas most likely to see temperatures fall
below freezing, namely the Upper Hood River Valley and the 
Cascade foothills of Marion, Linn, and Lane Counties.

As upper-level ridging builds on Friday, drier and warmer
weather is expected across the region, although there remains
some uncertainty in the progression of yet another upper low
over the Northeast Pacific. This low or open trough may move
nearer to the region and bring clouds and rain, although
confidence is relatively low and rainfall chances only reach
5-10% by late Friday night. -36


.LONG TERM...Saturday through Wednesday...An upper-level low or
open trough tracking from the Gulf of Alaska over the Northeast
Pacific will be the driver of sensible weather this weekend and
into early next week, and the forecast remains sensitive to its
low-confidence evolution. An upper low located nearby will 
favor cloudy skies and rainfall chances, while a position well 
to the west would see continued warm and dry weather. If it is
located off the northern CA or southern OR coast, the pattern
could allow sufficient moisture to move northward on its 
eastern flank to support convection along the Cascades. -36

&&

.AVIATION...Post frontal showers are expected to persist through 
the day with increasing chances for convection in the afternoon 
through at leas 01Z Thu. Highest probabilities lie along the 
Cascade foothills and to the north with around a 25-35% chance 
inland within the Willamette Valley. Have already observed 
thunder within the vicinity of some Willamette Valley terminals,
but has yet to be widespread. Thunder is challenging here as 
often it may be one storm that pops up, while other times it can
be a wide swath. In this case, because the flow is 
northwesterly (not as favorable) behind the previous system, 
would trend towards a more isolated thunderstorm scenario. 
Overnight, showers will slowly dissipate and clear. Dropping 
temperatures mean that there is a slight chance for frost 
formation over exposed surfaces. If skies remain cloudy though, 
those chances decrease significantly. Another limiting factor 
will be that winds are just slightly above what we would like to
see for more widespread frost formation. 

KPDX AND APPROACHES...Combination of MVFR and VFR conditions
with showers. Around a 30% chance of thunderstorms through 06Z
Thu. Thunderstorms will trend towards an isolated scenario. 
With passing storms, expect gusty outflow winds leading to LLWS 
type conditions. Note that atmospheric LLWS is not expected, but
rather environment induced conditions. -27

&&

.MARINE...Post frontal showers will increase probability for 
lightning over the waters through around 1700 today. Small Craft 
Seas persist due to a westerly swell combined with a westerly 
wind wave. These small craft seas are hovering right around 9-10
ft at 8 seconds. Have extended the advisory through Thursday 
morning, though will see a steady decline in seas shifting from 
west to east. In addition, there will be a strong ebb early 
Thursday morning for the Columbia River Bar. The inner waters 
will see lowering seas as early as early Thursday morning. Winds
will remain westerly through Friday morning, then shift to the 
north as a high pressure ridge sets up over the waters. This 
summer time pattern will bring increased winds to PZZ253 in the 
afternoon. While not quite a low- level jet, we could see a 
short burst of gusts up to 25 kt.

High pressure over the area will maintain more settled
conditions through early next week. -27

&&

.PQR WATCHES/WARNINGS/ADVISORIES...

OR...Frost Advisory from 1 AM to 9 AM PDT Thursday for ORZ104>110-
     114>118-123>125.

     Freeze Warning from 1 AM to 9 AM PDT Thursday for ORZ121.

     Freeze Watch from late Thursday night through Friday morning 
     for ORZ121-124-125.

     Winter Storm Warning until 5 AM PDT Thursday for ORZ126>128.

WA...Frost Advisory from 1 AM to 9 AM PDT Thursday for WAZ203>205-
     208.

     Winter Storm Warning until 5 AM PDT Thursday for WAZ211.

PZ...Small Craft Advisory until 5 AM PDT Thursday for PZZ210.

     Small Craft Advisory until 5 PM PDT Thursday for PZZ251>253-
     271>273.

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FXUS66 KMFR 151953
AFDMFR

Area Forecast Discussion
National Weather Service Medford OR
1253 PM PDT Wed Apr 15 2026

.DISCUSSION...The front is passing through the area this
afternoon, with rain, gusty winds, and mountain snow. Steady
rain will taper off as the front passes to the south and east
later today, with showers continuing overnight, and potentially
some isolated showers persisting into Thursday morning along the
coast and the northern Cascades.

The cold air mass behind the front looks to bring cool overnight 
lows from tonight into Thursday morning and again from Thursday 
night into Friday morning. A Frost Advisory will be in place for 
the Rogue, Applegate, and Illinois valleys for tonight into 
Thursday, as lingering cloud cover looks to keep temperatures just
above freezing concerns. Localized freezing conditions may be 
possible in some areas, notably in the southern Illinois Valley. A
Freeze Watch covers the Thursday night-Friday morning timeframe, 
as there's some question how cold that night will get.

A number of hazard products are in place to further communicate the 
impacts of this active period. A Winter Weather Advisory for the 
Cascades from Crater Lake northward and above 4000 feet remains in 
place through Thursday morning. A Wind Advisory for most of Lake 
County as well as the Warner Mountains and areas north of Alturas in 
Modoc County highlights dangerous travel conditions in these areas.

An upper ridge will bring drier conditions and warmer daytime highs 
on Friday and Saturday. Long-term guidance shows a low pressure 
system approaching from the northwest. Details for this system 
remain coarse, with some variations between the ECMWF and GFS 
outcomes. This system may bring a southerly flow pattern that tends 
to focus precipitation at Curry County as well as parts of western 
Siskiyou County, per ECMWF imagery. Or it might bounce off a ridge 
and linger over the Pacific before moving inland on Monday, per GFS 
imagery. Initial snow levels are in the 5000-7000 foot range, which 
would limit winter impacts. Showers may continue beyond Monday, 
depending on how this system behaves.


&&

.AVIATION (18Z TAFs)...

A front continues to pass through the region bringing rainfall, 
breezy winds, and ceilings just above MVFR. This will likely 
continue through early this afternoon, but we are expecting showers 
to become more isolated this afternoon with skies clearing behind 
the front. The big questions is how much clearing will occur 
tonight. At this time, we have omitted any visibility restrictions 
and low clouds overnight, and this may need further evaluation for 
subsequent TAFs. That said, at this time KRBG has the relatively 
highest probability for visibility restrictions at about 25% 
overnight. 

-Guerrero

&&

.MARINE...Updated 1200 PM PDT Wednesday, April 15, 2026...A passing 
front will continue to bring breezy winds and steep seas across all 
waters through tomorrow afternoon. Isolated showers are possible 
tonight through tomorrow morning, and there could be an embedded 
thunderstorm tonight (20%-25%) around and north/northwest of Cape 
Blanco. Localized areas of very steep and hazardous seas are 
possible north of Cape Blanco tonight. Conditions improve late 
Thursday afternoon; however, a weak thermal trough may bring gusty 
northerly winds to the waters south of Cape Blanco late Thursday 
into Friday. Another active system may bring additional rainfall and 
steep seas this weekend. 

&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...Frost Advisory from 3 AM to 9 AM PDT Thursday for ORZ024-026. 

     Freeze Watch from late Thursday night through Friday morning for 
     ORZ024. 

     Wind Advisory until 8 PM PDT this evening for ORZ030-031. 

     Winter Weather Advisory until 5 AM PDT Thursday for ORZ027. 

CA...Frost Advisory from 3 AM to 9 AM PDT Thursday for CAZ080. 

     Freeze Watch from late Thursday night through Friday morning for 
     CAZ080. 

     Wind Advisory until 8 PM PDT this evening for CAZ085. 

PACIFIC COASTAL WATERS...Small Craft Advisory until 5 PM PDT Thursday 
     for PZZ350-356-370-376. 

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

FXUS66 KPDT 152033
AFDPDT

Area Forecast Discussion
National Weather Service Pendleton OR
133 PM PDT Wed Apr 15 2026

.KEY MESSAGES...

- Mountain snow into Thursday

- Breezy to windy through Thursday

- Near- to sub-freezing morning lows Thursday and Friday for the 
  lowlands

&&

.DISCUSSION...
Satellite imagery shows a closed upper low centered over
southwest British Columbia early this afternoon. Meanwhile, a
robust cold front is trekking across eastern Oregon and far
southeast Washington. In the wake of the front, skies have
become clear to partly cloudy across much of the Columbia Basin
and vicinity, with upslope convective showers noted across the
Cascade crest. Winter weather headlines remain in effect, and 
confidence is high (80 percent) in an additional 2-6 inches of 
snowfall for the Washington Cascades and northern Blue
Mountains, and 4-8 inches for the Oregon Cascades. While the 
bulk of the steady snowfall has ended for the Cascades -- and 
will end through this afternoon for the Blues as the front sags 
southeast -- snow showers will persist through tonight into 
Thursday morning as the aforementioned upper low moves over
northeast Washington.

Breezy westerly to northwesterly winds have developed in the 
wake of the front and remain diurnally breezy to windy through 
Thursday. While winds of 20-30 mph coupled with gusts of 30-40
mph have developed in climatologically wind-prone locations,
confidence in the need for any wind headlines is low-medium 
(30-60 percent), highest for the Kittitas Valley, eastern 
Columbia River Gorge, lower Columbia Basin, and foothills of the
Blue Mountains. Winds will be locally stronger along exposed
ridges within the Columbia Plateau region.

The cold air mass associated with the low has prompted concerns
for near- to below-freezing morning temperatures. NBM 
calibrated probabilities still suggest medium-high chances 
(60-90 percent) of freezing temperatures for the Yakima and 
Kittitas valleys, medium probabilities (30-70 percent) along the
foothills of the Blue Mountains, and low-medium (20-50 percent)
for the lowest elevations including the eastern Columbia River 
Gorge and lower Columbia Basin. Freeze Warnings remain in effect
for tonight into Thursday morning where chances of freezing are
highest (Kittitas and Yakima valleys and the foothills of the 
northern Blue Mountains of Oregon). Will note there is still  
uncertainty in how much cloud cover will persist and how windy 
conditions will remain overnight into the morning hours, so
confidence in widespread freezing temperatures is shaky (50-60 
percent), but think areas of freezing temperatures still have a
high enough chance of developing to retain the warnings.

An upper-level ridge will likely (90 percent confidence) build 
into the Pacific Northwest Friday into the weekend, yielding 
lighter winds and mostly dry conditions. The main headline- 
worthy consideration for Friday will be near- to sub-freezing 
temperatures for the lowlands. This set-up looks more favorable 
for mostly clear to clear skies and lighter winds relative to 
Thursday morning, so while the coldest air mass will have exited
the region to the east, radiational cooling should be more 
efficient. Have not issued any Freeze Watches to avoid confusion
given the existing Freeze Warnings for Thursday morning.

Uncertainty in the 500-hPa pattern grows through the weekend, 
but some flavor of a 500-hPa closed low is advertised by all 
ensemble clusters to be in the vicinity of the Pacific 
Northwest Saturday through the remainder of the period.
Precipitation chances increase Sunday, but especially Monday and
Tuesday, in what is looking increasingly like a potential
convective set-up for portions of the forecast area. Another
deformation band similar to what was observed earlier in the
week is also looking like a potential outcome should the closed
low track inland along a supportive path, but confidence in 
that solution is currently low (20-25 percent).

&&

.AVIATION /18Z TAFS THROUGH 18Z THURSDAY/...
A cold front is moving across the area today, which will create 
gusty west wind and IFR ceilings in the vicinity of the frontal 
boundary, most notably at ALW and PDT early in the TAF period. 
Periods of light to moderate rain will obstruct visibility as 
low as 2 to 3SM in the vicinity of any of these aforementioned 
terminals and to around 3-5sm at BDN and RDM. Momentum behind 
the frontal boundary will maintain gusty winds of 20 to 30 knots
into the evening hours. 

&&

.Preliminary Point Temps/PoPs...
PDT  31  53  32  57 /  30  10   0   0 
ALW  34  54  36  57 /  50  30   0   0 
PSC  34  61  34  63 /  20   0   0   0 
YKM  30  59  31  61 /  10   0   0   0 
HRI  32  59  34  62 /  20   0   0   0 
ELN  29  51  30  57 /  10   0   0   0 
RDM  22  48  21  57 /  40  10   0   0 
LGD  28  46  29  54 /  70  40  10   0 
GCD  25  45  25  54 /  70  40   0   0 
DLS  35  56  35  63 /  40   0   0   0 

&&

.PDT WATCHES/WARNINGS/ADVISORIES...
WA...Winter Weather Advisory until 11 PM PDT this evening for 
     WAZ030-522.
     Freeze Warning from 11 PM this evening to 9 AM PDT Thursday 
     for WAZ026-027.
OR...Winter Weather Advisory until 11 PM PDT this evening for 
     ORZ502.
     Freeze Warning from 11 PM this evening to 9 AM PDT Thursday 
     for ORZ507.
     Winter Storm Warning until 5 AM PDT Thursday for ORZ509.

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

FXUS65 KBOI 152036
AFDBOI

Area Forecast Discussion
National Weather Service Boise ID
236 PM MDT Wed Apr 15 2026

.KEY MESSAGES...
- Gusty winds and a chance of thunderstorms this evening, then 
  snow level lowering to valley floors tonight.

- Subfreezing morning temperatures tonight, Friday, and 
  Saturday in the agricultural areas.

- Warmer and drier over the weekend, with another chance of 
  precipitation early next week.

&&

.SHORT TERM /Through Friday Night/...
Afternoon radar and satellite imagery showing a well defined
cold front stretching through central Oregon. The front will 
push through SE Oregon late this afternoon and across southwest
Idaho this evening. Showers and isolated thunderstorms will
develop ahead of the front with enhancement possible as it 
pushes into the west-central ID mountains. The wind gust 
potential along the front is 30-40 mph with higher end gusts of 
up to 50 mph from stronger showers/storms.

Colder air will be quick to move in behind the front tonight,
allowing for a changeover to snow down to valley floors. This
will mostly impact the western Magic Valley where showers 
linger into Thursday morning. Otherwise lower elevations dry out
behind the front overnight while mountains see a continued 
chance of snow showers. Light accumulations (1 to 3 inches) are 
expected across mountain valleys through mid-morning Thursday
while higher elevations pick up an additional 3 to 8 inches of
snow. In the Snake Plain temperatures will drop to around 
freezing Thursday morning so have opted to go with a Freeze 
Warning. The highest confidence for freezing temperatures is 
across the Upper Treasure Valley (Boise metro and points east) 
and western Magic Valley. Feel less certain about a freeze in 
the lower Treasure Valley where continued northwest winds could 
keep temperatures above freezing, especially near the ID/OR
border.

Friday is notably cooler with high temperatures around 15 
degrees below normal and breezy northwest winds making it feel 
colder. Even warmer spots in the lower Snake Plain will see wind
chill values only top out in the mid 30s to low 40s. With the 
cold air mass in place have much higher confidence in widespread
freezing temperatures Friday morning across the Snake Plain. 
This will be a colder and longer duration freeze than what we 
see tonight. Otherwise, Friday is dry across most of the area, 
with scattered snow showers lingering in the west-central Idaho 
mountains. Temperatures will warm 5 to 10 degrees from Thursday 
and lighter winds lessen the chill. Another frost/freeze is 
possible Friday night, but will hold off on any products for 
now.

&&

.LONG TERM /Saturday through Wednesday/...
A ridge building into the northwest region will bring warmer 
and drier conditions Saturday through Sunday. Saturday morning 
will still see temperatures hovering near freezing in the lower 
Treasure Valley and 5-10 degrees below freezing over other 
areas. Sunday is expected to see peak temperatures 5-10 degrees 
above normal. 

Guidance uncertainty remains over the arrival timing of a closed 
upper low digging into the region from the Gulf of Alaska early next 
week. Overall ensemble guidance has delayed the arrival to late 
Monday, with a chance of precip over the SE OR areas. A slight 
warming trend should stay intact through midweek due to the south-
southwest flow expected from this system. For now, precipitation 
chances will increase to 20-40% area-wide Tuesday and Wednesday. 
Guidance consensus generally projects higher precip coverage over 
the entire CWA on Wednesday as the low passes over the area. Breezy 
south/southwest winds are anticipated early next week as the low 
inches closer, becoming W-NW following its passage.

&&

.AVIATION /18Z Wednesday through Thursday/...
Issued 1154 AM MDT WED APR 15 2026
Low VFR/MVFR ceilings in rain and IFR/LIFR in mtn snow. Snow levels 
5-7kft MSL. A cold front will bring sharp wind shifts and intensify 
precip after 20Z, with MVFR/IFR in heavier rain showers. A 25% 
chance of thunder with small hail/graupel along the front. Snow 
levels rapidly lowering to valley floors following the front. 
Scattered light snow showers expected Thursday morning through 
afternoon. Surface winds: SE-SW 10-20 kt with gusts 20-35 kt, then W-
NW 15-30kt with gusts up to 40 kt this afternoon with the frontal 
passage. Winds aloft at 10kft MSL: W-SW 25-40 kt. 


KBOI...Showers continuing with periods of MVFR ceilings and reduced 
visibility this afternoon. A strong cold front will arrive this 
afternoon around 22Z. The front will bring a sharp NW wind shift, 
heavier precip, temporary MVFR/IFR, and potential for 
graupel/lightning. Conditions returning to VFR following the front. 
Surface winds: SE 10-15 kt this morning, then NW 15-25 kt with gusts 
up to 35 kt following frontal passage this afternoon/evening.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...Freeze Warning from 4 AM to 10 AM MDT Thursday for IDZ012-014-
     016.
     Freeze Warning from midnight Thursday night to 10 AM MDT 
     Friday for IDZ012-014-016.
     Wind Advisory until 8 PM MDT this evening for IDZ015-030.
OR...Freeze Warning from 4 AM MDT /3 AM PDT/ to 10 AM MDT /9 AM 
     PDT/ Thursday for ORZ064.
     Freeze Warning from midnight MDT /11 PM PDT/ Thursday night to 
     10 AM MDT /9 AM PDT/ Friday for ORZ064.
     Wind Advisory until 8 PM MDT /7 PM PDT/ this evening for 
     ORZ061-063.
--------------------------------------------------------------------

FXUS66 KSEW 151056
AFDSEW

Area Forecast Discussion
National Weather Service Seattle WA
356 AM PDT Wed Apr 15 2026

.SYNOPSIS...
A cold front continues to shift eastward today, with steady snow
coming to an end in the Cascades. However, expect widespread
showers Wednesday across the area in the cool, unstable post-
frontal air mass. A few isolated thunderstorms are possible this
afternoon. Drier but cool conditions then develop later this
week until the next frontal system approaches the region
offshore this weekend.

&&

.SHORT TERM /TODAY THROUGH FRIDAY/...
A cold front passed through western Washington yesterday 
evening/this morning. This is being driven by an upper level 
low/trough that will dig southward today across the state. The radar 
remains active this morning with precipitation continuing in the 
lowlands and Cascades this morning. A convergence zone is keeping 
showers going between Seattle and Everett. Snow has been falling at 
all of the Cascade passes, and the surface temperatures up there 
have been just below freezing. The winter storm warning will 
continue through 11 PM this evening, with a couple additional rounds 
of snow expected through the day today. A couple of the snow-bands 
later may be able to produce heavier snow rates.

For the remainder of the area today, the cold air aloft with the 
trough sinking over will create an unstable airmass for a chance of 
convection today. SPC has the coastal areas in a general risk of 
thunder today, although the thunder risk will encompass the entire 
coverage area today. The risk is capped at 30% (with the coastline 
and interior/Puget Sound areas having the best chance of seeing 
thunder). These showers/thunderstorms are expected to be scattered 
in nature, with any breaks of sun during the morning able to add to 
the 200-300 J/kg of CAPE in place. The window for thunder will be 
from late morning through early evening. The main concerns are 
lightning, and downpours containing heavy rain and graupel/small 
hail. No organized severe weather is expected. Highs today remain 
cool - upper 40s to low 50s in the lowlands, and 30s/40s in the 
mountains. Winds will remain light out of the west 5-10 mph.

The trough moves out going into Thursday. North flow behind the 
trough will bring in cooler Canadian air into the region. Conditions 
will be dry going into Thursday/Friday. Main concern will be the 
potential for any fog/frost/freeze conditions next couple mornings 
to finish the week. Mitigating factors will be the potential for 
some cloud coverage overnight, boundary layer conditions and the wet 
grounds from recent rains may favor some patchy fog development in 
spots. Light to calm winds and any clearing that does take place 
will allow temperatures to fall into the low 30s and upper 20s 
Thursday and Friday morning. Probabilities for a hard freeze are 
greatest in the Chehalis Valley/South Interior areas, with remaining 
lowland areas more likely to see frost at this point. If 
frost/freeze conditions do form, it will be important to protect any 
plants/crops outside susceptible to the cold conditions.

HPR

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
Ensemble guidance continues to bring the next low pressure
system south from the Gulf of Alaska offshore past the region
this weekend. There remains a significant spread in the 
eastward extent of the associated front across the region, which
would impact the potential for additional rainfall this weekend.
While there remains some mention across most of the area, the
chances remain highest across the Olympic Peninsula and
coastline. Regardless, this looks to be a weaker system than
the currently passing front and a more seasonable air mass with
lowland temperatures returning to the 60s and snow levels
returning back above the Cascade passes.

12

&&

.AVIATION...
A cold front moved through the terminals this morning, with a post-
front convergence zone producing additional showers in Puget Sound. 
The showers were rotating around an anti-cyclonic meso-low, with 
some outflow turning the winds northeasterly at KSEA and KBFI this 
morning. The convergence zone is expected to last through 16-18Z, 
with winds turning back to the southwest 4-8 kt. Ceilings this 
morning have ranged between MVFR/VFR, but will trend towards VFR 
through the day. A trough will dig southward today, with north flow 
increasing late tonight/Thursday aloft. Breaks in the clouds with 
sun today will help destabilize the atmosphere for convection during 
the day. There is a 20-30% chance of thunder in the terminals this 
afternoon (most likely window is from 20Z-00Z this afternoon denoted 
with PROB30). Cloud tops on any storms are likely to remain under 
20,000 ft. Coverage will be scattered in nature. Main concerns are 
lightning, heavy downpours that may contain graupel/small hail, and 
gusty/variable outflow winds. Conditions will dry going into 
Thursday with an increased likelihood of MVFR ceilings Thursday 
morning. Winds become light out of the northwest tonight/Thursday 
less than 5 kt.

KSEA...Vicinity showers with a convergence zone to continue through 
late this morning. Brief NE winds with this feature will switch to 
the SW 4-8 kt around 16-18Z (few gusts up to 20 kt before the 
switch). MVFR ceilings improving to VFR this morning, with MVFR 
likely Thursday morning. Showers to continue through the day and a 
30% chance of thunder (most likely window is from 21Z-00Z). Drier 
conditions into Thursday morning. Lightning, graupel/downpours, and 
variable breezy winds are possible with storms in/near the terminal. 
Winds to become light under 5 kt later this evening (brief variable 
period possible from 22Z-02Z).

HPR

&&

.MARINE...
Winds have peaked over the waters this morning in the wake of
the passing cold front. Widespread showers can be expected
through the day with a few stronger ones potentially bringing
lightning and stronger wind gusts. Meanwhile, seas remain 7 to
12 ft over the coastal waters as they increase today. Even if
short of 10 ft, conditions will be rather steep with a dominant
period around 8 seconds over the coastal waters.

Conditions begin to subside later in the week with weak high
pressure building over the waters Thursday through Saturday. The
next front will approach the waters over the weekend bringing
another round of gusty winds and building seas over the waters
into the weekend.

12

&&

.HYDROLOGY...
No river flooding is expected during the next seven days.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...Winter Storm Warning until 11 PM PDT this evening for Cascades 
     of Pierce and Lewis Counties-Cascades of Snohomish and 
     Northern King Counties-Cascades of Southern King County-
     Cascades of Whatcom and Skagit Counties.

PZ...Small Craft Advisory until 10 AM PDT this morning for Grays 
     Harbor Bar.

     Small Craft Advisory until 5 AM PDT Thursday for Coastal 
     Waters From Cape Flattery To James Island 10 To 60 Nm-
     Coastal Waters From Cape Flattery To James Island Out 10 
     Nm-Coastal Waters From James Island To Point Grenville 10 
     To 60 Nm-Coastal Waters From James Island To Point 
     Grenville Out 10 Nm-Coastal Waters From Point Grenville 
     To Cape Shoalwater 10 To 60 Nm-Coastal Waters From Point 
     Grenville To Cape Shoalwater Out 10 Nm.

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