Heavy Snow in Oregon, January 13 to 14, 2020

Area Forecast Discussion
National Weather Service Medford OR
411 AM PST Mon Jan 13 2020

.DISCUSSION...

We're in a lull between systems this morning, but rain and snow
showers will pick up in intensity later this morning around 10 am.
Snow levels are slightly higher than 2000 feet this morning and
those snow levels will continue to rise throughout the morning
hours as warmer air moves in ahead of the next approaching low.
Snow levels should top out around 3500 feet this evening. As the
snow levels rise, the flow will also turn more southwesterly. This
should allow Siskiyou Summit and areas near Mt Shasta City to see
a little more snow than they have been seeing during this entire
event. Look for around 3 to 5 inches around Siskiyou Summit and 2
to 4 inches around Mt Shasta City over the next 24 hours.

 Downed trees and significant snow accumulation over the Cascades
will significantly impact travel today through Tuesday. As for
other locations, the snow will be more of a nuisance and
shouldn't significantly impact travel. For more information on
detailed storm total snow accumulation, read the winter storm
warning(WSW) product.

We'll finally get a break in the weather from late Tuesday to
about mid day Wednesday. Guidance is showing a strong storm in the
Pacific from Wednesday into Thursday. The flow will turn more
southerly and put the Mt Shasta region and the Klamath Mountains
under focus for significant snowfall Wednesday night. Interstate 5
will likely be impacted near Mt Shasta City during this time. We
should also mention that the latest deterministic models are
showing some very strong winds over the outer waters, so high
winds along the coast are possible Wednesday into Wednesday night.
Snow levels will be around 2500 to 3000 feet for most of this
event.

Some thunderstorms are possible over the waters and along the
coastline Wednesday night. We're not expecting those storms to
push that far onto land on the other hand.

-Smith

&&

.AVIATION...For the 13/12Z TAF Cycle....VFR cigs and vsbys will be
most common across the area through early morning, but there will be
also be areas of both IFR and MVFR conditions near showers and snow
showers with higher terrain obscured, especially along the Cascade
crest.

Conditions will deteriorate again mid-morning (about 18 UTC) through
Monday night. MVFR cigs/vsbys will dominate with widespread
obscuration of higher terrain, occasional IFR, and southwest to west
low levels winds becoming gusty and strong (especially from the
Cascades eastward) as the next front brings more precipitation to
the area. For west side valleys including KMFR and KRBG, the valleys
may be sheltered enough to cause wind shear concerns as winds near
2000 ft will be noticeably stronger.

Freezing levels will be near 2000 feet msl through Monday morning,
then briefly rising to 3500 feet msl during Monday afternoon. The
next front will bring lowering freezing levels Monday night down to
1500 feet msl by early Tuesday morning. -miles

&&

.MARINE...Updated 210 AM PST Monday 13 Jan 2020...A series of
strong fronts will continue to bring high to very high and steep to
very steep seas through the week.

Very high seas will continue into Monday morning and a high surf
advisory is now in effect until mid-morning. Winds will let up to
below advisory strength early Tuesday morning through Tuesday night,
but seas will remain steep and hazardous to small craft.

The strongest of the fronts looks to be Wednesday into Wednesday
night with very heavy seas possible. Have issued a Gale watch for
Wednesday afternoon and evening as most models agree a surface low
will strengthen as it approaches the Oregon coast causing winds to
near Gale force. There is some difference between models in the
possible track for this surface low. Therefore, some fine tuning in
where and for how long the strongest winds will persist still
requires further attention, so stay tuned for emerging details.

More fronts will follow into the weekend creating more periods of
heavy seas, with very strong winds. -miles

&&

.MFR WATCHES/WARNINGS/ADVISORIES...
OR...Winter Weather Advisory until 10 AM PST Tuesday for ORZ029-030.
     Winter Storm Warning until 10 PM PST Tuesday for ORZ027-028-030.
     Winter Weather Advisory until 10 AM PST Tuesday for ORZ031.
     Winter Weather Advisory until 10 AM PST Tuesday above 2000 feet
     in the for ORZ023>026.
     High Surf Advisory until 10 AM PST this morning for ORZ021-022.
     Winter Storm Warning until 10 AM PST Tuesday above 2500 feet in
     the for ORZ024.
     Winter Storm Warning until 10 AM PST Tuesday above 3000 feet in
     the for ORZ025-026.
     Winter Weather Advisory until 10 AM PST Tuesday for ORZ028.

CA...Winter Weather Advisory until 10 AM PST Tuesday for CAZ085.
     Winter Weather Advisory until 10 AM PST Tuesday above 3500 feet
     in the for CAZ080.
     Winter Weather Advisory until 10 AM PST Tuesday for CAZ082-083.
     Winter Storm Watch from Wednesday afternoon through Thursday
     morning above 3000 feet in the for CAZ082-083.

Pacific Coastal Waters...Gale Watch from Wednesday morning through Wednesday evening for
     PZZ350-356-370-376.
     Small Craft Advisory from 1 AM Tuesday to 10 AM PST Wednesday
     for PZZ350-356-370-376.
     Hazardous Seas Watch from Wednesday morning through Wednesday
     evening for PZZ350-356-370-376.
     Hazardous Seas Warning until 1 AM PST Tuesday for
     PZZ350-356-370-376.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE MEDFORD OR
554 AM PST MON JAN 13 2020

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0553 AM     SNOW             7 W TOKETEE FALLS       43.29N 122.58W
01/13/2020  U0.0 INCH        DOUGLAS            OR   DEPT OF HIGHWAYS

            SNOW ACCUMULATING ON HIGHWAY 138 AROUND 1700
            FEET.

&&

CZS