[ W WA | SW WA and W OR | SE WA and NE OR | NE WA and N ID ]

Western Washington


067 
FXUS66 KSEW 200359
AFDSEW

Area Forecast Discussion
National Weather Service Seattle WA
900 PM PDT Tue Mar 19 2019

.SYNOPSIS...A strong upper level ridge with low level offshore 
flow will result in one more sunny day Wednesday - with likely 
record high temperatures. Lower upper level heights and weakening 
low level offshore flow will keep conditions a bit cooler - but 
still dry on Thursday. A front will spread light rain northeast 
across the area on Friday. There will be a chance of showers next 
weekend with near normal temperatures.

&&

.SHORT TERM /TONIGHT THROUGH FRIDAY/...Gusty easterly winds tonight 
will ease, with clear skies. Wednesday will be another warm day over 
the interior with the thermal trough right over Puget Sound. The 
coast will have a bit of onshore surface flow, which will keep highs 
there around ten degrees lower than today.

Offshore flow decreases Wednesday night into Thursday and a weak 
southerly surge will develop over the Oregon coast - bringing late 
night and morning stratus to the coast and portions of the interior 
by Thursday morning. Low temperatures will drop into the 40s, with 
highs on Thursday reaching into the mid 60s through the interior -
well above normal. High temperatures along the coast will remain 
near normal on the coast, in the mid 50s. Southerly flow aloft may 
allow isolated showers over southern sections in the afternoon and 
evening. 

On Friday a weakening trough will move inland helping to spread 
light rain onto the coast in the afternoon and inland Thursday 
evening. 

.LONG TERM /SATURDAY THROUGH TUESDAY/...from previous 
discussion...Showers will follow on Saturday. Models are generally 
dry on Sunday, then more weak systems arrive Monday and Tuesday. 
Have generally followed the models as far as pops. Temperatures will 
still be a few degrees above normal each day, with highs generally 
55-60. Burke

&&

.AVIATION...Low level offshore flow continue tonight with VFR 
conditions. The air mass will remain dry and stable with 
southeasterly flow aloft. Breezy to gusty easterly surface winds 
will persist across portions of the southern Sound this evening, 
easing after midnight.  

KSEA...VFR conditions with easterly winds 10-15 knots through this 
evening. Gusts still possible over the next few hours, but winds 
will east after 06Z.

&&

.MARINE...Offshore flow will persist into Wednesday afternoon. 
Breezy winds near the gaps of the coastal terrain - strongest 
easterly winds will be along the Central Strait of Juan de Fuca. 
Light onshore flow developing on Thursday ahead of a weakening front 
spreading into the region on Friday.

&&

.HYDROLOGY...River flooding is unlikely over the next seven days.

&&

.SEW WATCHES/WARNINGS/ADVISORIES...
WA...None.
PZ...Small Craft Advisory until 5 AM PDT Wednesday for Coastal Waters 
     From Cape Flattery To James Island 10 To 60 Nm-Coastal 
     Waters From Cape Flattery To James Island Out 10 Nm-West 
     Entrance U.S. Waters Strait Of Juan De Fuca.

     Small Craft Advisory until 2 AM PDT Wednesday for Central U.S. 
     Waters Strait Of Juan De Fuca.

&&

$$

www.weather.gov/seattle

[ W WA | SW WA and W OR | SE WA and NE OR | NE WA and N ID ]

Southwestern Washington and Western Oregon


091 
FXUS66 KPQR 200410
AFDPQR

Area Forecast Discussion
National Weather Service Portland OR 
909 PM PDT Tue Mar 19 2019

.SYNOPSIS...Low pressure passing by to the south will bring a small
chance of showers to the southern part of the forecast area Wed.
Otherwise, conditions will generally remain dry, with above normal
temperatures and breezy offshore flow. Will see a better chance for
rain on Fri or Sat as a Pacific frontal system moves onshore, with
additional chances for rain early next week.

&&

.SHORT TERM...Tonight through Friday...Visible satellite imagery
shows some high clouds moving across the forecast area this afternoon
as an area of low pressure approaches the region from the south. This
may help to keep temps slightly cooler than yesterday for some areas,
but they will still be unseasonably warm. As of 2 PM Salem and
Astoria have already broken their daily record high, with several
stations within a degree or two of the record.

Expect conditions to gradually change tonight and Wed as our upper
level ridge moves out of the area and low pressure moves into
southern Oregon. Guidance continues to show some wraparound moisture
impacting portions of the forecast area Wed, with a slight chance of
showers possible generally south of Salem. Otherwise, Wed should
remain mostly dry, with breezy offshore flow weakening through the
day. Temps will also be slightly cooler Wed as mid and high clouds
increase due our proximity to the area of low pressure.

Cooler temps will persist into Thu as onshore flow increases, with
some post-frontal showers lingering around through the day. Expect
conditions to generally remain dry, but there are enough ensemble
members showing slight chance PoPs over the area that we can't remove
it from the forecast. Suspect this moisture will generally keep the
area cloudy rather than wet. Guidance then shows another frontal
system moving across the region on Fri. There is still some
uncertainty with the timing and strength of this front, but the
general trend is to bring the return of widespread wetter weather on
Fri.

.LONG TERM...Friday Night through Tuesday...Guidance continues to
show a modest frontal system moving onshore late Fri, with post-
frontal showers lingering into Sat. Snow levels will likely lower to
around pass level over the weekend as the upper level trough moves
over the region. A passing shortwave ridge may allow conditions to
briefly dry out on Sun, but another series of frontal systems look to
move across the Pac NW early next week as the pattern starts to
become more active.

&&

.AVIATION...Dry offshore flow will allow widespread VFR
conditions to prevail through most of the region over the next 24
hrs. One caveat is that southerly winds have begun to develop
along the central Oregon coast, bringing IFR stratus and fog from
KONP southward this evening. The IFR is looking like it may
continue through the night at KONP, although it is also possible
that it will temporarily pull just off the coast for a while
overnight if any light offshore winds are able to develop. The 
southerly winds will work up the north Oregon and south 
Washington coast during the day Wednesday, spreading the IFR cigs
northward as well. Expect IFR conditions to reach KAST sometime 
during the late afternoon or evening hours. 

KPDX AND APPROACHES...Minimal impacts the next 24 hours as 
offshore flow and dry low levels will allow VFR conditions to
prevail. Gusty winds will continue, especially east of the
terminal out toward the Gorge. Pyle

&&

.MARINE...Southerly winds have begun to develop over the central
Oregon waters this evening, while offshore winds continue north 
of Cape Lookout. The southerly winds should spread north through
the north Oregon and south Washington coastal waters on
Wednesday. The next organized front is expected to arrive on Fri.
This system should be a round of solid small craft advisory
southerly winds, with the potential for a brief period of low-end
gales. Another system is possible late in the weekend or early
next week.

Seas remain 6 to 8 ft  through Thu, mainly as a result of two 
swell trains. First is a westerly swell of 6 to 7 ft, with other 
coming from the southwest at 4 to 6 ft. Seas will increase a bit 
more later in the week, pushing above 10 ft later Fri afternoon, 
and holding at 12 to 14 ft Fri night through Sat night. Seas 
subside on Sunday, but still near 10 ft. Pyle

&&

.PQR WATCHES/WARNINGS/ADVISORIES...
OR...None.
WA...None.
PZ...None.
&&

$$

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This discussion is for Northwest Oregon and Southwest Washington 
from the Cascade crest to 60 nautical miles offshore. This area is 
commonly referred to as the forecast area.

[ W WA | SW WA and W OR | SE WA and NE OR | NE WA and N ID ]

Southeastern Washington and Northeastern Oregon


164 
FXUS66 KPDT 200520
AFDPDT

Area Forecast Discussion
National Weather Service Pendleton OR
1020 PM PDT Tue Mar 19 2019

Updated aviation discussion

.SHORT TERM...Tonight and Wednesday...High pressure continues over 
the region but is being undercut by a low pressure system that will 
eventually move into California on Thursday. Meanwhile, there will 
be some increasing high level clouds over central Oregon overnight 
that will slowly spread northward Wednesday. Some of the moisture 
associated with the low pressure will begin to move into southern 
Oregon Wednesday and could make its way into central Oregon late in 
the day or evening. Otherwise, forecast area remains warm and dry 
through Wednesday.

.AVIATION...06Z TAFS...VFR conditions will prevail through the 
period with some very isolated patchy fog late tonight and early 
Wednesday for some possible MVFR/IFR conditions which will burn off 
by midday.  A system over northern California will spread some mid 
and high level clouds over the area late tonight and Wednesday. 
Winds will generally be less than 10 kts. 

&&

.PREV DISCUSSION... /issued 420 PM PDT Tue Mar 19 2019/ 

SHORT TERM...Tonight through Friday. Upper level ridge centered
to our northeast providing another fair weather day. Temperatures
in most locations are up a few degrees from yesterday. Satellite
shows an upper low is moving toward California. Mid and high level
clouds from this system are slowly overspreading central Oregon
this afternoon. For tonight the mid and high level clouds remain
over central Oregon. Mainly clear further to the north. As the low
moves into California on Wednesday expect clouds to overspread the
forecast area. Slight chance of rain along the Oregon Cascades.
Not much change for Thursday as the systems are slow moving due to
a blocking high in the center of the country. The low will be in 
Nevada with clouds spreading northward across the region. Still a
chance of light rain for central Oregon and especially the
Cascades with a southeasterly upslope flow. Temperatures remain
mild the next few days with highs in the 50s and freezing levels
6-9k feet. This will continue the snowmelt with many rivers and 
streams running high. Another upper level trough approaching the
Pacific northwest will push a cold front through the area Friday
afternoon into Fri night with rain likely. 94

LONG TERM...Friday night through Tuesday...Models continue to be in 
good agreement in the overall pattern with only minor spatial and 
temporal differences.  An upper level trough will move across the 
area Friday night and Saturday producing widespread precipitation 
over Oregon with lighter amounts over Washington.  Snow levels 
are expected to be around 6000 feet but fall to near 4000-4500 
feet by Saturday evening.  Some lingering showers are expected 
Sunday over the mountains of Northeast Oregon as the system slowly 
exits the region.  A shortwave upper level ridge is expected to move 
over the region Sunday night.  GFS is a little faster with the 
approach of the next upper level low off the coast of Oregon Monday. 
Most of the energy with this system remains on the west side 
of the Cascades as the main low moves northward into western BC by 
Tuesday afternoon.  As a result, most of the precipitation will be 
over our western zones, but embedded shortwaves in the southwest 
flow will allow for some precipitation moving across the eastern CWA 
as well, especially by Tuesday.  Snow levels are expected to rise 
again to around 5500-6000 feet by Tuesday.  Daytime highs will 
remain near to slightly above normal through the period.  Earle



&&

.PRELIMINARY POINT TEMPS/POPS...
PDT  31  56  34  57 /   0   0   0   0 
ALW  29  60  37  56 /   0   0   0   0 
PSC  27  60  36  58 /   0   0   0   0 
YKM  31  59  35  60 /   0   0   0   0 
HRI  29  60  36  59 /   0   0   0   0 
ELN  27  57  33  58 /   0   0   0   0 
RDM  27  55  31  54 /   0  10  20  20 
LGD  27  57  31  58 /   0   0   0   0 
GCD  33  63  33  56 /   0   0  10  10 
DLS  32  58  37  56 /   0   0  10  10 

&&

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

$$

91/91/91

[ W WA | SW WA and W OR | SE WA and NE OR | NE WA and N ID ]

Northeastern Washington and Northern Idaho


006 
FXUS66 KOTX 200552
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
1052 PM PDT Tue Mar 19 2019

.SYNOPSIS...
Dry and mild conditions will continue through Friday. Clouds and
the chance for showers will increase late Friday and persist into
the weekend. Temperatures over the weekend into early next week 
will be pretty close to average with most locations climbing into 
the 50s.

&&

.DISCUSSION...
Tonight through Thursday: The high pressure and dry conditions
will continue for this period. No major weather impacts are 
expected. This will be the warmest stretch of days for the year 
so far as highs creep up into the upper 50s and low 60s for the 
region. The lows will be in the near freezing range. The warmer 
temps are expected to melt low land snow and create rises on area 
small streams and creeks. As of now, any rises are expected to be 
below action stage. 

Friday: The omega block that was over region will shift East as a
shortwave trough presses into the region from the West. The 
models are fairly consistent with the the timing of the system. 
The areas of precip differ. The GFS is brining showers over the 
Cascades by Friday afternoon, while the ECMWF is keeping the 
precip out the Inland Northwest until later in the evening. 
Increasing cloud cover will keep the highs a few degrees cooler 
then the previous days highs with most locations reaching into the
50s. /JDC

Friday Night through Sunday: Precipitation chances will be
increasing Friday night into Saturday as a weak low pressure
trough moves inland. Rain amounts this weekend look to be light
and showery. Forcing with the weak trough is not impressive. The
best forcing associated with the upper level jet is expected to be
over central California and the Great Basin. Ensemble mean
precipitation amounts suggest a tenth or two across the Idaho 
Panhandle and mountains of northeast Washington with lesser 
amounts across the Columbia Basin, Palouse and West Plains. Light 
rain amounts are good news. So far, the melt of our late season 
snow across the lowlands has been gradual with minimal impacts. At
this time, the rain expected this weekend will not make any 
significant contribution to snow that is melting.

Monday and Tuesday: Our forecast for Monday remains dry under the
influence of a short-lived high pressure ridge. There is a good
chance that showery weather will return Monday night into Tuesday
as a large upper low settles off the coast. We will be watching
moisture wrapping around this large upper low closely. At this
time, it looks like the most significant rains will be focused
over California. Temperatures early next week look to be at or
slightly above average. By early next week, a good deal of the
snow across the Palouse, Spokane area, and Upper Columbia Basin
will be melted. And at this time, the pattern early next week
isn't raising any red flags for excessive rain. /GKoch

&&

.HYDROLOGY...

So far the melting of our lowland snowpack has been gradual with
warm days, light winds, and chilly nights. Some of our creeks and
streams are starting to respond to runoff with small to moderate 
rises. Streams fed by runoff from the Palouse are often first to
respond and we are seeing some rises on Hangman Creek (south of 
Spokane), Paradise Creek (Moscow), and the Palouse River near
Potlatch. Since these creeks were running lower than normal last
week, there has been ample capacity for the increased runoff. We 
expect more water to enter creeks and small streams over the next 
36 to 48 hours as lowland snow over the Palouse and West Plains 
ripens and the rate of snowmelt increases. Some minor field 
flooding may occur across the Palouse which is a fairly frequent 
occurrence late in the winter. So far, we haven't seen gauges 
rise in far north Idaho, northeast Washington or along the 
Cascades. It may take more time for the deeper snow at higher 
elevations to ripen, melt and enter our creeks and streams.

The Hydrologic Outlook on our web page was allowed to expire this
morning. It served its purpose raising awareness of potential
hydrologic hazards as our lowland snow melts. If any specific 
flooding hazards develop in upcoming days, advisories or warnings 
will be issued to highlight the impacts. Overall, this dry weather
pattern is just what we needed to begin releasing runoff without
causing flooding. At this time, we don't see any big rain events 
coming the next 7 to 10 days which is also good news. /GKoch

&&

.AVIATION...
06Z TAFS: VFR conditions with clear skies and light winds is
expected for at least the next 24 hours.


&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        31  61  31  61  31  59 /   0   0   0   0   0   0 
Coeur d'Alene  32  62  33  62  30  57 /   0   0   0   0   0   0 
Pullman        30  59  31  59  31  57 /   0   0   0   0   0   0 
Lewiston       34  65  35  63  33  61 /   0   0   0   0   0   0 
Colville       29  63  30  62  29  59 /   0   0   0   0   0   0 
Sandpoint      34  61  34  62  32  57 /   0   0   0   0   0   0 
Kellogg        33  61  34  63  32  57 /   0   0   0   0   0   0 
Moses Lake     30  64  34  63  34  62 /   0   0   0   0   0   0 
Wenatchee      33  57  34  58  35  56 /   0   0   0   0   0  10 
Omak           34  61  35  61  34  58 /   0   0   0   0   0   0 

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
ID...None.
WA...None.

&&

$$

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