An incoming front brought high winds to several locations in southwest and south central Oregon.
Every event with a place to put it; 2 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
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 several locations in southwest and 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 25, 8:41 AM PST, 3 hours 6 minutes earlier.
Area Forecast Discussion
National Weather Service Medford OR
841 AM PST Fri Dec 25 2020
.UPDATE...Updated wind gusts in Klamath Basin and the central-
southern Rogue Valley.
&&
.DISCUSSION...The surface inversion has broke here in the central
Rogue valley, temperatures went from around 32 degrees to 51
degrees and gusty winds have begun to mix down. At the southern
end of the valley winds have been gusting for a while and are
expected to only increase over the next six hours. Have increased
gust speeds here into the lower 30s (kt) to better line up with
some of our aviation products. Similar increases to wind gusts
were applied in the Klamath Basin and for the same reason, where
so far this morning gusts are being reported in the mid-to-upper
20s and also will be steadily increasing into the afternoon.
Light rain accumulations are being reported in the southern coast
range (0.38" by a trained spotter) and at the coast (0.09 at the
Brookings airport). Stronger radar returns are just now nearing
the Siskiyous and snow is expected to start in about 2 hrs time
around 6+ kft and about 3 hrs at 5+ kft, although we have gotten a
few reports of light snow in the Mt. Shasta City area already.
Snow will start out heavier and wet as warm air moves in the
central third of the troposphere cools. It will take about 5 to
9 hours from the start before most places begin to see a lighter,
fluffier snow.
This all puts the forecast well on track. More details can be
found in the previous discussion below. -Miles
&&
.AVIATION...For the 25/18Z TAFs...Conditions are still mainly
VFR this morning, but they have begun to deteriorate. A strong front
will bring increased southerly winds, intensifying precipitation,
lowering snow levels, areas of MVFR, mountain obscurations, and (at
elevations above 3000 to 4000 ft) areas of snow and blowing snow.
These hazardous conditions will continue through this evening with
blowing snow producing areas of much lower visibilities.
Low level wind shear (LLWS) will remain a concern for all of our
area through this afternoon, and from the Cascades eastward through
this evening with very strong southwest winds aloft advance and
along the front with the gusty south to southwest at the surface.
Terrain channeling will produce stronger winds in the southern Rogue
Valley, the Shasta Valley, and many valleys of the East Side. Winds
will gradually ease later this evening and overnight. But, the next
disturbance will continue areas of MVFR and mountain obscuration
with a new burst of rain and snow on Saturday morning. -DW
&&
.MARINE...Updated 800 AM PST Friday 25 Dec 2020...A low centered
offshore of northern California will deepen as it moves north
through the Oregon waters today, creating strong winds and very
steep and hazardous seas through this evening. Coastal influences
combining with a slow moving front and the deepening low are likely
to cause winds to peak at storm force over most areas this morning
through early this evening, before easing late in the evening and
overnight. But, seas will remain very high and very steep into
Saturday morning while wind seas gradually diminish.
Seas will remain steep through the rest of the weekend as moderate
west swell continues, but will finally drop below 10 feet late
Monday. The break in the active pattern will be short however, as
the next front is expected to arrive late Tuesday into Wednesday,
with another round of gusty south winds and steep wind-driven seas.
Models are in good agreement that the active pattern will continue,
with multiple systems expected through the rest of the week,
although the details of winds and seas for each individual system
remains uncertain due to considerable spread in the model solutions.
-BPN/DW
&&
.PREV DISCUSSION... /Issued 651 AM PST Fri Dec 25 2020/
DISCUSSION...
A powerful frontal system is on our doorstep this Christmas
morning poised to bring gusty, strong southerly winds to some of
the forecast area as well as areas of moderate to heavy
precipitation today into Saturday. Returns have been increasing
rapidly on the radar this morning, though most of the these
returns have been elevated, as not much has been observed reaching
the surface as of yet.
These elevated returns on the radar are an indication that our
area will some evaporational cooling this morning, which will be a
significant player for snow levels. For instance, it's currently
41 degrees with a dewpoint of 16 degrees at Mount Shasta City as
of 6 AM PST. A trained spotter called around 2 AM PST from around
3790 feet in Mount Shasta City indicating light snow falling with
the temperature in the upper 30s. With a drier low level
southeast wind flowing into the Mount Shasta area today we expect
temperatures will gradually cool as precipitation gets going.
Snow levels in the Shasta area are looking a bit tricky for today,
as they could range anywhere between 2500 and 4000 feet based on
the guidance. A good indicator is usually dewpoints on the MOS
guidance. This morning the MOS guidance does not show dewpoints
getting above freezing until mid to late Saturday morning. Based
on that and the dynamical model guidance it now appears snow
levels are most likely to settle in the 2500 to 3500 foot range
in the Mount Shasta area, so the Winter Storm Warning there has
been lowered to 3kft elevations. Snowfall rates and temperatures
will be critical to how much snow falls there, but models suggest
1.2 to 2.2 inches of water there, so expect 6 inches in the lower
areas of the warning area to around 20 inches up higher where it's
all snow. The heaviest precipitation rates will be this afternoon
into this evening when snowfall rates of 1 to inches per hour
are expected along and near I-5. Higher rates are possible on the
SW side of Mount Shasta.
A number of wind advisories were also added to the forecast for
today and a high wind warning was added for much of the east side.
Models show 700mb winds today of 60 to 75 mph, which usually is
close to what we get for gusts at the high blower sites. One area
we spent a good amount of time looking at was the Siskiyou
Mountains. It appears there will be a 3 to 9 hour period of time
there when winds will gusts 60 to 80 mph. This coupled with
periods of light to moderate snowfall mean localized blizzard
conditions are likely in exposed areas. Thus, if you're venturing
into the mountains today, be sure you know where you're going and
how to get back in case you lose visibility. Saturday will be a
better visibility day with more snow on the ground for those
wanting to check out the new snow.
We'll be updating graphics on our web site to be consistent with
our forecast updates, but, in the meantime, please check out our
text products for the Winter Storm Warning Product and our wind
headlines.
The current weather system will continue into Saturday with
periods of snow for mid-upper elevations. Guidance suggests rising
snow levels Saturday, but temperatures are cooling at 700mb and
500mb and there will be precipitation falling from those layers.
Therefore, have hedged snow levels lower than the guidance, as
it's unlikely they'll rise even if surface temperatures do.
After a break Sunday into Monday ensembles and deterministic
models are suggesting a series of strong and wet frontal systems
pushing into the area beginning on the 29th or 30th and continuing
well into the first week of January. Snow levels with that one
look a to waver between 4kft and 7kft, but moisture amounts look
more significant than we've seen since at least mid-December for
the 7 day period. Also, rain amounts look like they could be very
healthy along the coast- enough to put a dent in the drought that
we're still very much in. ~BTL
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...High Wind Warning until 4 AM PST Saturday for ORZ030-031.
Winter Weather Advisory until 10 AM PST Saturday for ORZ030.
Wind Advisory from noon today to 10 PM PST this evening for
ORZ029.
High Wind Warning until 4 PM PST this afternoon for ORZ021-022.
Wind Advisory until 10 PM PST this evening for ORZ023>025.
Winter Weather Advisory until 10 AM PST Saturday above 4500 feet
in the for ORZ027-028.
Wind Advisory until 7 PM PST this evening for ORZ026.
CA...High Wind Warning until 4 AM PST Saturday for CAZ085.
Wind Advisory from noon today to 10 PM PST this evening for
CAZ084.
Winter Storm Warning until 10 AM PST Saturday above 3500 feet in
the for CAZ080.
Winter Storm Warning until 10 AM PST Saturday above 3000 feet in
the for CAZ082-083.
High Wind Warning until 7 PM PST this evening for CAZ081.
Pacific Coastal Waters...Storm Warning until 7 PM PST this evening for
PZZ350-356-370-376.
Gale Warning until 7 PM PST this evening for PZZ350-356.
Hazardous Seas Warning from 7 PM this evening to 1 AM PST
Saturday for PZZ350-356-370-376.The national radar mosaic for the moment the first event began.
2 high wind. Local standard time, as filed.
The ODOT sensor on US 395 at Valley Falls recorded a gust to 61 mph at 25/1335 PST and 25/1341 PST. The Lakeview BLM Fuels QD#1 sensor, located just west of Valley Falls, recorded a gust to 60 mph at 25/1246 PST.
The ODOT sensor on US 101 at Humbug Mountain recorded several gusts exceeding 57 mph during this interval. The peak gust was 68 mph recorded at 25/1346 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: 926378, 926376.