An incoming front brought high winds to at least one location in south central Oregon.
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Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS MFR wrote it up.
An incoming front brought high winds to at least one location in south central Oregon.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Medford, OR wrote its last area forecast discussion before the first event at Dec 30, 3:00 AM PST, 2 minutes earlier.
Area Forecast Discussion
National Weather Service Medford OR
300 AM PST Wed Dec 30 2020
.DISCUSSION...30/06Z NAM/GFS in. 30/00Z EC in.
The northern hemispheric projection shows a wave number of five
around the globe this morning. This is normally a progressive
pattern and that is what will be happening over the next week as
system after system will move into the Pacific Northwest.
The ridge that brought the recent dry weather is now moving out of
the area and the upstream trough will move onshore Wednesday. The
warm front associated with the incoming system is now moving north
through the area. It is mostly dry, but cloud cover has increased
quite a bit over the past 24 hours. The trailing cold front will
move onshore Wednesday, and it will bring precipitation to most,
if not all, of the Medford forecast area Wednesday into Wednesday
night. Amounts will not be excessive, with 0.75 to 1.50 inches
falling along the coast and in the Coast Range. It will be a
significant snow event in the Cascades above 4000 feet or so. Snow
levels are forecast to fall from 4000 to 5000 feet Wednesday
afternoon to 3500 to 4000 feet early Thursday morning. 6 to 12
inches of snow are forecast for the southern Oregon Cascades. The
higher terrain of the east side will see up to 6 inches of snow,
but amounts in the east side valleys will mostly be below 2
inches.
The front will also bring strong winds east of the Cascades
Wednesday afternoon and evening, and a High Wind Warning is in
effect for highway 31 from Paisley to Summer Lake, as well as the
higher terrain of Lake county and far eastern Klamath county. It
also includes the Warners in Modoc county. Southwest gusts to 65
mph are possible. There is also a Wind Advisory for the southern
Shasta Valley near Weed from Wednesday afternoon through Wednesday
evening with south wind gusts up to 50 mph expected.
Post-frontal showers will gradually diminish, with only light
shower activity expected Thursday. There will be a break
Thursday night as the next ridge in the train moves through, and
the ridge axis will break to the east of the Medford forecast area
Thursday night. The next trough will move onshore Friday evening
and the associated front will move onshore Friday afternoon. This
will bring another round of rain, snow, and wind to the area.
Precipitation amounts will not be excessive, and they will
diminish quite a bit moving inland from the the coast. Little of
the precipitation will make it to the east side, with a few
inches of snow for the Cascades.
A wetter front will arrive late Saturday, and this one will be
stronger than the Friday front and similar to the Wednesday/
Wednesday night system. This means that another round of wind
related warnings and advisories may be needed for the east side,
Shasta valley, and possibly the coast.
Turning to precipitation, Integrated Vapor Transport (IVT), a
good measure of how much moisture is pointed at our region, is
forecast to be in the top 10 percent for this time of year. This
is especially significant considering we're around the wettest
time of year now. Snow levels are expected to be around 5000 feet
at the onset of precipitation, lowering to around 4000 feet behind
the front. Periods of heavy rain are expected Saturday night and
Sunday morning, and rivers and streams are expected to rise.
Showers will diminish late Sunday behind the front, and after
that point, confidence in the forecast decreases. The pattern will
remain active, but there is uncertainty regarding the storm
tracks, and differences in the storm tracks can make a big
difference in the amounts of rain and snow and the strength of the
winds.
While the precipitation amounts from any one system will not be
excessive, the cumulative effects of this series of storms may
lead to flooding issues in coastal basins such as the Coquille.
&&
.AVIATION...For the 30/06Z TAFs...Low clouds and fog/freezing
fog of the LIFR to IFR variety are likely this evening in the
Scott Valley and Grants Pass area, gradually lifting overnight
into Wednesday morning as it cools and winds increase above the
boundary layer. Additionally, some MVFR visibilities in haze are
expected along the Curry county coast. Otherwise, incoming mid-
high level clouds and low surface dewpoints should keep other
areas VFR tonight.
A strong cold front pushing in from the west Wednesday is expected
to bring low level wind shear for a period of time at all TAF
locations at some point on Wednesday. While directional shear is
anticipated initially, strong winds pushing in just above the
surface along and the coast Wednesday from 18Z onward will result in
some speed shear, as well, continuing wind shear conditions longer.
Rain is likely to begin at the coast and Umpqua Basin in the
morning, spreading inland over the course of the day. Snow level is
likely to be near 4kft MSL as precipitation moves in. The consensus
of the guidance suggests that KLMT has a 70% probability of
precipitation beginning as snow. It appears that KLMT is likely to
get an inch or more of snow Wednesday evening. ~BTL
&&
.MARINE...Updated 230 AM PST Wednesday, 30 Dec 2020...A cold
front will move through the waters today bringing gale force winds
to areas north of Gold Beach (Gusts of 40-45 kt). Steep to very
steep short period wind waves (10-13 feet) will develop and
combine with a long period west swell (also 10-13 feet) resulting
in very hazardous seas and dangerous bar crossings. The front is
likely to move onshore early this afternoon, with winds becoming
westerly and easing some after frontal passage. Seas will still
remain high and steep behind the front, however, averaging 14-17
feet at 16 seconds after frontal passage tonight. Waves will then
gradually lower into Friday night.
Another strong low will move through this weekend bringing another
strong cold front. Seas will likely remain high and steep with
another round of gale forecast winds possible. Some data suggests
seas reaching 24 to 26 feet next Monday and Tuesday. Beyond this
weekend, the forecast looks exceptionally active as more storm
systems move through. -Spilde
&&
.BEACH HAZARDS...Updated 230 AM PST Wednesday 30 Dec 2020...
Westerly swell will peak around 17 feet at 16 seconds this afternoon
and tonight. This will result in waves that run up farther on the
beach than usual. As a result, a high surf advisory is in effect
this afternoon through Thursday morning. These large breaking waves
will create hazardous conditions along and within the surf zone, and
could inundate beaches and low lying shorelines. Stay away from the
surf zone and off of jetties. Area beaches may become hazardous due
to dangerous surf conditions. Additional long period waves late this
week, this weekend and into next week will likely result in
additional "high surf" headlines. -Spilde
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...High Surf Advisory from 1 PM Wednesday to 10 AM PST Thursday for
ORZ021-022.
High Wind Warning from 10 AM Wednesday to 1 AM PST Thursday for
ORZ030-031.
Winter Weather Advisory from 1 PM Wednesday to 7 AM PST Thursday
for ORZ027-028-030.
CA...High Wind Warning from 10 AM Wednesday to 1 AM PST Thursday for
CAZ085.
Wind Advisory from 1 PM to 10 PM PST Wednesday for CAZ081.
Pacific Coastal Waters...Small Craft Advisory until 4 AM PST Saturday
for PZZ356-376.
Gale Warning from 7 AM to 4 PM PST Wednesday for
PZZ350-356-370-376.
Small Craft Advisory until 7 AM PST Wednesday for PZZ350-370.
15/15/18The national radar mosaic for the moment the first event began.
1 high wind. Local standard time, as filed.
A CWOP observer at Summer Lake recorded a gust to 59 mph at 30/0315 PST.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Oregon in 2020Every state in 2020This day in weather historyWarnings in Oregon, December 2020
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 926787.