Sunday, January21, 2018 L-36.com


Marine Weather and Tides
Winthrop, WA

Version 3.4
What's New / NOTES
6/25/2017 - NOAA is having a major issue that impact the 7 day forecast load times. Many users are reporting problems. The issue has been reported.
5/23/2017 - Worked with NOAA again to speed up the 7 day forecast load times. Thanks to them for being responsive.
5/19/2016 - There were issues with the 3 day airport observation history. I switched to another data source. Let me know if you see any issues with the data feeds.

Sunrise 7:36AMSunset 4:49PM Sunday January 21, 2018 10:11 AM PST (18:11 UTC) Moonrise 10:04AMMoonset 9:42PM Illumination 25% Phase: Waxing Crescent; Moon at 5 days in cycle
NOTE: Some of the data on this page has not been verified and should be used with that in mind. It may and occasionally will, be wrong. The tide reports are by xtide and are NOT FOR NAVIGATION.
Marine Forecasts
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7 Day Forecast for Marine Location Near Winthrop, WA
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location: 48.47, -120.18     debug


Area Discussion for - Spokane, WA
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Fxus66 kotx 211140
afdotx
area forecast discussion
national weather service spokane wa
340 am pst Sun jan 21 2018

Synopsis
An active weather pattern is expected through the week. Snow and
rain will develop today over the region. More weather systems
will bring significant precipitation Tuesday night into Wednesday
and again next weekend with a mix of rain and snow across the
lower elevations and snow in the mountains. Travel impacts are
expected at times, especially over the mountain passes.

Discussion
Today and tonight... The next pacific storm system will envelope
the region today. Satellite indicates a deep upper low just off
the bc and northwest us coast this morning. The baroclinic region
just ahead of this cold core low pressure features a moderately
deep fetch of moisture that will enhance along the front into
widespread mountain snow... Valley rain or wet generally minorly
accumulating snow and mostly basin rain... Beginning in the
morning over the cascades and western basin and during the
afternoon over the eastern basin and idaho panhandle.

Significant mountain snow accumulation is a near certainty... With
8 to 12 inches in the high cascades and 6 to locally 10 inches in
the northeast washington and north idaho ranges... With a bit less
in the central panhandle since the moisture feed will become
attenuated by a long southerly overland trajectory by the time
the front reaches this area this afternoon and evening.

Still... Slippery conditions crossing lookout pass are possible
tonight... And travelers heading across the cascade and okanogan
highland passes will encounter serious winter driving conditions.

The areas of uncertainty as far as winter conditions will be the
valleys near the cascades including the western columbia and
okanogan river valleys... And the valleys of the northeast
mountains and the purcell trench. An early onset of snow this
morning before temperatures have time to recover from morning lows
may bring a couple inches to the okanogan valley floor today and
the benches along the columbia river in chelan county. The winter
weather advisories will be expanded to include these lower
elevation locations... In addition to the existing advisories for
the waterville plateau... Okanogan highlands and the cascades. In
the northeast mountains and north idaho accumulating snow will
begin later in the day when valley temperatures may be high enough
to limit accumulations to generally minor 1 to 2 inches of wet
slush on area roads... So there is guarded optimism that the
advisories will not have to be expanded this afternoon to these
locations.

The basin east of the waterville plateau will likely see mainly
rain or non-accumulating wet snow from this system. The front will
move rather slowly and take well into the evening tonight to track
into idaho with a downslope precipitation shadow beginning late
today in the cascades lee and deep basin.

Late tonight through Monday night a general moist westerly zonal
regime will set up with frequent snow showers near the cascade
crest and driving into the idaho panhandle. A few minor waves
embedded in this flow may allow some scattered snow showers to
backfill into the eastern and northern basin on Monday but no
further organized systems of significant snow accumulations are
expected until the next storm system on Tuesday. Fugazzi
Tuesday through next weekend: it will be quite the roller coaster
of weather throughout the week as a pair of warm and wet storm
systems impact the region. The first to pass through Tuesday into
Wednesday with a second Saturday into Sunday. The air mass will
cool enough prior to the arrival of each slug of moisture to allow
for some snow for the northern valleys but snow levels look to
migrate back into the mountains as each system pushes inland. This
has been the trend for most storms this month and it does not
look like we are going to deviate much this week. The good news is
that moisture will continue to pile up in the mountains, mainly
in the form of snow, not only welcome by winter recreationists but
for our summer water supply.

Precipitation will envelope the region early Tuesday ahead of a moist
laden warm front. Precipitation is expected to start off as snow
for most communities along and north of highway 2, potentially
becoming moderate to heavy at times while transitioning to rain
from south to north Tuesday afternoon through early Wednesday.

There is ample cooling left behind Monday's wave to knock 850mb
temperatures near -3c or cooler for my northern zones but details
are still wavering regarding what surface temperatures will be
sitting at during the first 6 hours of precipitation, especially
below 2500 feet and along the highway 2 corridor and just north.

It is not a matter if it will change to rain but when. Confidence
by Wednesday is above average that most valleys warm above
freezing and transition to rain. Locations that can hold snow
until Wednesday will have the potential to pick up 3-6 inches of
wet snow. Otherwise a few tenths to 2 inches will be more common.

Heavier amounts are expected in the cascades and across the
northern mountains toward the selkirks.

A cold front will press through Wednesday night driving snow levels
back toward the valley floors. Precipitation will wane in the lee
of the cascades and travel impacts will once again switch back
toward the idaho panhandle to lookout pass, camas prairie, and
higher elevations in between like deary and clarkia. Snow will
also continue along the cascade crest and at stevens pass. May
even see some light snow accumulations on the elevated terrain of
the palouse.

Models continue to indicate the coolest air mass arriving behind
this cold front with 850mb temperatures dipping near -4c in the
columbia basin to -7c along the canadian border. If this does not
change, the next slug of moisture arriving over the weekend will
likely start as snow for most locations outside the lower basin.

However, as mentioned above, it will be another warm system with a
gradual south to north warm-up. Depending where the surface low
track, the warmer air may arrive just as the precipitation ends so
a 6-12 hour period of mild conditions is expected but it may be a
dry and breezy warmth... Stay tuned. Sb

Aviation
12z tafs: increasing and thickening mid level clouds will suppress
low stratus and fog formation this morning and while some patchy
brief ifr conditions are possible before sunrise the threat is not
high enough to include in any tafs. A moist meridional cold front
will sweep the forecast area west to east today. Light snow will
move into the keat area by 16z with MVFR cigs, followed by a
rain snow mix by afternoon. Mainly light rain will spread across
the columbia basin and reach the kpuw and kgeg area TAF sites by
21z-22z with -ra or -rasn with MVFR cigs. Partial clearing is
expected from west to east behind the front this evening... But
light upslope flow may promote low stratus ceilings in the kgeg
area late tonight and through 12z Monday. Mjf

Preliminary point temps pops
Spokane 39 29 36 27 35 33 10 90 20 10 20 90
coeur d'alene 39 30 35 27 35 32 10 90 50 20 20 80
pullman 41 32 38 29 38 35 10 80 30 20 10 80
lewiston 45 34 44 32 43 35 10 50 20 20 10 50
colville 39 29 35 24 34 31 60 90 30 10 40 80
sandpoint 39 30 34 26 33 31 20 90 60 40 20 80
kellogg 39 29 34 27 34 31 10 80 60 50 20 70
moses lake 42 30 41 28 39 33 100 10 10 10 40 80
wenatchee 36 27 39 25 32 30 90 20 10 10 70 90
omak 35 26 34 23 31 30 100 60 10 10 60 90

Otx watches warnings advisories
Id... None.

Wa... Winter weather advisory from 7 am this morning to 7 pm pst this
evening above 1500 feet for wenatchee area.

Winter weather advisory from 7 am this morning to 10 pm pst this
evening for okanogan highlands.

Winter weather advisory until 10 pm pst this evening for east
slopes northern cascades.

Winter weather advisory from 7 am this morning to 7 pm pst this
evening above 2000 feet for okanogan valley-waterville
plateau.



Weather Reporting Stations
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Airport Reports
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AirportDistAgeWind ktVisibilitySky/WeatherTempDewPtHumidityPressure
Omak Airport, WA35 mi19 minSW 910.00 miOvercast37°F30°F79%1016.4 hPa

Wind History from OMK (wind in knots)
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Last 24hrS5SE6SE3CalmSW5SE5SE4CalmCalmCalmCalmCalmCalmCalmCalmCalmS5CalmS6SW10S9SW6SW8SW9
1 day agoSE4S5S7S6S6S4S5SE4SE5SE3SE3E3CalmS4SE4S5SE5S3S5CalmSE3SE4CalmSE5
2 days agoS6S4S6S3SE4S8S9S8S9SW6SW6S7SW5E4S4S3S3SE5CalmS3S5SE4S4S3

Tide / Current Tables for
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Tide / Current Tables for
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Weather Map and Satellite Images
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Weather Map
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IR Satellite Image from GEOS
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GOES Local Image of PacificNorthwest    EDIT
Geos

Wind Forecast for Spokane, WA (13,3,4,5)
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Ground Weather Radar Station Spokane, WA
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Disclaimer:
The information on this web site has not been checked for accuracy. It is for entertainment purposes only and should be independently verified before using for any other reason. There are five sources. 1) Documents and manuals from a variety of sources. These have not been checked for accuracy and in many cases have not even been read by anyone associated with L-36.com. I have no idea of they are useful or accurate, I leave that to the reader. 2) Articles others have written and submitted. If you have questions on these, please contact the author. 3) Articles that represent my personal opinions. These are intended to promote thought and for entertainment. These are not intended to be fact, they are my opinions. 4) Small programs that generate result presented on a web page. Like any computer program, these may and in some cases do have errors. Almost all of these also make simplifying assumptions so they are not totally accurate even if there are no errors. Please verify all results. 5) Weather information is from numerious of sources and is presented automatically. It is not checked for accuracy either by anyone at L-36.com or by the source which is typically the US Government. See the NOAA web site for their disclaimer. Finally, tide and current data on this site is from 2007 and 2008 data bases, which may contain even older data. Changes in harbors due to building or dredging change tides and currents and for that reason many of the locations presented are no longer supported by newer data bases. For example, there is very little tidal current data in newer data bases so current data is likely wrong to some extent. This data is NOT FOR NAVIGATION. See the XTide disclaimer for details. In addition, tide and current are influenced by storms, river flow, and other factors beyond the ability of any predictive program.