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Marine Weather and Tides Mount Shasta, CA Version 3.4

NOTICE 8/26/2020 The 7 day forecast is taking about 5 seconds to load but it will eventually load. NOAA is still working on it. 8/18/2020 NOAA continues to have trouble. Wind guest will occasionally be left off graphs. I am working with NOAA to resolve the issue. 12/16/2019 NOAA is having trouble with requests that include wind gusts. I am posting graphs without wind gusts until it gets fixed. 10/9/2019 Updated the Marine Zones. 9/4/2019 Fixed the weather maps due to NOAA moving them. 7/25/2019 New feature in the Airports section gives a link to 5 minute updates for data reports.

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Sunrise 7:28AM

Sunset 5:11PM

Sunday January 17, 2021 2:16 AM PST (10:16 UTC)

Moonrise 10:30AM

Moonset 10:06PM

Illumination 16%

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.

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7 Day Forecast for Marine Location Near Mount Shasta, CA

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Area Discussion for - Medford, OR

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FXUS66 KMFR 170456 AFDMFR

Area Forecast Discussion National Weather Service Medford OR 856 PM PST Sat Jan 16 2021

UPDATE. We issued a dense fog advisory for the Klamath Falls Basin this evening due to low visibilities observed at the Klamath Falls Airport and along US Highway 97. Satellite is also suggesting there are some low visibilities in the Shasta Valley tonight. Look for these poor driving conditions to continue for most of the night. There could be some freezing fog in the mix as well with temperatures falling below 32 degrees in some spots east of the Cascades tonight.

Aside from that, the forecast looks pretty good. It's hard to say if the fog will really build into some of these other valleys west of the Cascades tonight. The upper level clouds should inhibit some of that fog formation. We could very well see some dense fog a few hours before sunrise around Medford, Roseburg and Grants Pass.

-Smith

SHORT TERM. /Issued 251 PM PST Sat Jan 16 2021/ Through Monday Night . Here in the Rouge Valley and most other west side valleys, Shasta Valley is the exception, the clouds have eroded and the sun has finally broken through. Roseburg, which broke out sooner than the Rogue Valley, has already exceeded the expected maximum temperature, with other west side valleys are still on pace to meet theirs. The Klamath Basin is far less fortunate. Fog has remained locked in there through the morning and is not eroding with much pace, it is unlikely to erode completely before filling back in tonight. The Klamath Basin and Shasta Valley are not going to meet their respective maximum temperatures.

A short wave will flatten out the ridge Saturday night into Sunday. The front associated with this one will move onshore Sunday morning, and it looks to be weaker than the Friday front. Just a few hundredths of an inch of precipitation will fall late Saturday night through Sunday along the north coast and the Umpqua Basin. Snow levels will be above 7000 feet ahead of the front, and will drop down to 3500 to 4000 feet behind the front. Patchy fog is possible in west side valleys, mainly the Rogue, Illinois and Umpqua, with others developing a stratus deck just above the surface instead.

Strong northerly flow will develop Sunday night after the front passes, first impacting areas on the Coast Range and in the Mount Shasta City area. Winds will gust to around 30 mph along the coast and coast ranges. This will also mark the start of prolonged drying conditions. Can not rule out patchy fog in the Umpqua and upper Rogue Valley with the front possibly producing a few hundreths of rain. Inversions that support fog will delay these winds from reaching the surface until they break late Sunday morning.

The northerly winds turn east-northeast and flow offshore Monday. This will accelerate drying in the region, especially at the southern coast range. The east winds will create downslope warming in Brookings. This will be most prominent on Monday because the marine layer is slower to erode, compared to the summer, on Sunday. Temperatures may approach 70 on Monday, but currently 67 is the expected MaxT. Winds east of the Cascades will peak Monday afternoon as the upper-level low moves over southern Nevada/central California. -Miles

LONG TERM. /Issued 251 PM PST Sat Jan 16 2021/ Tuesday January 19th through Saturday January 23rd . The extended period begins under deep north to northeasterly flow with the area under the eastern periphery of an upper level ridge and a closed low over southern California. Deep east to northeasterly flow will be winding down as the day progresses Tuesday and pressure gradients relax. A fairly dry air mass will be in place due to this east to northeasterly flow, and this should limit fog and low cloud development for valleys both Tuesday and Wednesday mornings. With upper level ridging in place, dry conditions will continue through at least Thursday morning.

As we head into Thursday, models continue to have their differences but do agree that we'll be heading back into an active pattern. The next low pressure system moves into the region Thursday. The GFS clips the western portions of the forecast area, while the EC brings the bulk of the energy and moisture into California. Both models lean toward a drier trend with the Thursday system and wouldn't be surprised to see future runs trend even drier. Regardless, have leaned toward the National Blend of Models for the forecast, which keeps the area dry until Thursday afternoon with the best precipitation potential remaining along and west of the Cascades into Friday. Snow levels with this system look to be around 3500 to 4000 ft, but with light precipitation expected, snow impacts should be minimal. Then, a brief period of upper level riding nudges back into the area with dry conditions expected Friday into Saturday. Another system will approach the area Sunday morning and this will be a time period to monitor the potential for lower snow levels. It's much too soon to speak of any details or any level of confidence, but it will be something to keep an eye on. Stay tuned for updates as the time frame gets closer. /BR-y

AVIATION. For the 16/18Z TAFs . LIFR/IFR fog/stratus continues to impact most terminals this morning. While some lower conditions could persist much of the day (especially some of the deeper west side valleys), expect some improvement to VFR by early afternoon. LIFR/IFR conditions probably return though again tonight. A weak front could bring a little light rain to Coos and northwest Douglas Counties late tonight or first thing Sunday morning. -Spilde/BR-y

MARINE. Updated 230 PM PST Saturday, 16 Jan 2021 . Seas are diminishing but will remain high and steep this evening. Improvement late tonight will be very brief.

The next cold front will move through the waters early Sunday morning and a new long period west swell will build in. Behind the front, strong high pressure will build to the north and a thermal trough will set up along the coast. This will allow north winds to increase, and a gale warning has been issued, which covers south of Cape Blanco beyond 10nm from shore. Winds and seas are expected to peak late Sunday night, but the gales will persist into Monday morning with high and steep seas across all of the coastal waters. Also, elsewhere in the waters, north winds will be at advisory strength.

Of note, seas Sunday morning through Sunday evening will be a mix of two west swells, one 7 ft at 13 seconds and another 6 ft at 24 seconds Sunday morning building to 13 ft at 19 seconds Sunday night with steep to very steep wind seas. As the longer period swell builds in Sunday evening into early Monday, expect large breaking waves along the coast and dangerous bar crossings.

With high pressure offshore and a thermal trough at the coast, north winds will remain gusty and likely reach another peak on Monday afternoon with gales or near gale force winds possible again in the southern portion of the outer waters. Meantime, seas are likely to remain high and steep through Monday evening. This pattern will likely persist through Tuesday with northerly winds remaining strongest south of Cape Blanco.

BEACH HAZARDS. Updated 200 PM PST Saturday, 16 Jan 2021 . Another very long period swell will arrive late tonight and build into Sunday night. Due to the length of period (20-25 seconds), these high-energy waves will have the capability of running up much farther on the beach and could catch beachgoers off guard. A beach hazards statement is in effect for the potential of sneaker waves late tonight into Sunday afternoon. This long period swell will build further Sunday evening through early Monday, with large breaking waves expected of 20 to 25 feet. Thus, a High Surf Advisory is in effect for late Sunday evening into Monday morning.

Use extreme caution along and near the beaches. Observe the ocean from a distance. Jetties, rocks, logs and bar entrances are not safe places to be during these periods of significant waves. The Pacific Ocean is both cold and powerful. Large waves can easily sweep people and large objects into the water. NEVER turn your back on the ocean!

MFR WATCHES/WARNINGS/ADVISORIES. OR . Beach Hazards Statement from 3 AM PST Sunday through Sunday afternoon for ORZ021-022. High Surf Advisory from 10 PM Sunday to 7 AM PST Monday for ORZ021-022. Dense Fog Advisory until 9 AM PST Sunday for ORZ029-030.

CA . Dense Fog Advisory until 9 AM PST Sunday for CAZ081-084.

Pacific Coastal Waters . Small Craft Advisory until 10 PM PST this evening for PZZ350-356-370-376. Small Craft Advisory from 10 AM Sunday to 7 AM PST Monday for PZZ350-356-370-376. Gale Warning from 10 AM Sunday to 7 AM PST Monday for PZZ376.

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Weather Reporting Stations

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Airport Reports

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Airport	Dist	Age	Wind kt	Visibility	Sky/Weather	Temp	DewPt	Humidity	Pressure
Mount Shasta, CA	1 mi	20 min	N 0	10.00 mi	Fair	35°F	32°F	89%	1031.4 hPa

Link to 5 minute data for KMHS

Wind History from MHS (wind in knots)

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Tide / Current Tables for Trinidad Harbor, California

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Tide / Current Tables for

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Weather Map

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GEOS Local Image of CentralWestCoast    EDIT
NOTE: East coast views moved to GEOS-16. They are experimental and not well supported by NOAA so they may not be correct so be warned. This change required redoing a large amount of the GOES code. If the image you are expecting is not showing, please let me know. You may need to use the EDIT function to update your location.
Link to Loop

Other links: Northern Pacific     Contential US     Full GOES-East

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Ground Weather Radar Station

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