A couple of strong, slow moving fronts brought a combination of heavy swell and large wind waves to the southern Oregon coast.
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.
A couple of strong, slow moving fronts brought a combination of heavy swell and large wind waves to the southern Oregon coast.
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 27, 2:59 PM PST, 1 hour 1 minute earlier.
Area Forecast Discussion
National Weather Service Medford OR
259 PM PST Wed Dec 27 2023
.SHORT TERM...Tonight through Friday night...Winds have begun to
diminish but will remain gusty and strong into this evening. Weed,
in the southern Shasta Valley, recorded a peak south-southeast gust
of 65 mph this morning, while Acorn Woman Peak, in the Siskiyou
Mountains of southern Jackson County, had a peak gust of 80 mph.
A cold front over the area will continue to diminish in strength
overnight with decreasing coverage of showers. The snow level is
around 5500 to 6000 feet with precipitation mainly on and near
south facing slopes.
A break between systems will be short, late tonight into Thursday
morning. The next frontal system will be similar in its track, and
a bit weaker. A warm front will lift north through the area
Thursday afternoon and evening with increasing southerly winds. A
cold front will follow early Friday into Friday evening. A Wind
Advisory has been issued for the southern Rogue Valley, from
Ashland to Medford for Thursday evening through Friday evening,
with gusts again expected to reach 45 mph. Winds elsewhere do not
look to reach advisory strength, with a peak gust of around 40 mph
forecast for the Weed area and 25 to 35 mph across the east side.
Snow levels will rise to 8000 feet Thursday with very light rain
limited mainly to the coast and southern Siskiyou County. More
widespread light rain will be primarily Friday afternoon and
Friday night from the coast to the Cascades and into Klamath and
eastern Siskiyou counties, with a snow level around 6500 feet.
Rainfall amounts will be highest in southern Siskiyou County, at
around a half inch.
.LONG TERM...Saturday through Wednesday...Synoptic model forecasts
are similar in the overall pattern being somewhat benign during this
period. Initially, a late-week wind-producing trough weakens and
exits the region Saturday. Then following are a couple of weaker
upper lows to come into the west coast. The first comes through
Sunday through Sunday night as a splitting weak system that should
direct most of its impacts into California, leaving our region
mainly dry (Pops 15-30% coast and 5-10% east side). High pressure
takes hold soon after for Tuesday and Tuesday night. Another trough
impacts the region with higher rain potential (Pops 50% coast to 15
percent far east side) Tuesday night through Wednesday. Looking at
the ensemble situational awareness tables, nothing unusual is
jumping out in the percentiles to indicate significant impacts in
this weekend through mid-week period. Stavish
&&
.AVIATION...27/18Z TAFs...VFR levels under overcast ceilings and
clear visibility continue for most of northern California and
southern Oregon. Gusty southerly winds continue along the surface,
and wind shear is still a concern. Southerly winds of 40 to 50 kts
at 2000 feet are possible through the day, especially west of the
Cascades and over higher elevation terrain. These winds will start
to decrease in coverage this afternoon, but remain over higher
terrain through the TAF period.
Showers are continuing over Josephine, Jackson, and Siskiyou
counties and a few scattered showers are getting east of the
Cascades. Snow levels will remain at 5000 to 6000 feet through the
TAF period, keeping most precipitation as rainfall rather than snow.
Showers look to continue into this evening before dissipating into
the nighttime. Showers may locally lower ceilings and visibilities
as well as obscuring terrain, and extra caution is encouraged with
the continuing combination of showery activity and gusty winds. -TAD
&&
.MARINE...Updated 230 PM Wednesday December 27, 2023...Elevated
southerly winds and fresh swell are sustaining very steep and
hazardous seas in all waters. Gale winds are possible through the
evening, especially in waters beyond 15 nm from the coast. Waves of
17 to 21 feet at 15 to 17 seconds are expected. A Gale Warning will
remain in place for all waters until 10 PM this evening.
Winds will calm through the day Thursday, but very steep westerly
swell arriving overnight will sustain dangerous and chaotic seas in
all waters. Waves of 20 to 25 feet at 16 to 17 seconds are possible
through Thursday evening. A Hazardous Seas Warning is in place from
10 PM this evening through 5 PM Thursday evening to reflect
continuing dangerous conditions.
Seas will calm slightly through Friday morning, although steep seas
are likely to continue. Southerly winds will return Friday
afternoon, bringing the possibility of gale winds to outer waters as
well as very steep and hazardous seas in all waters. Confidence is
not complete in areas that may be affected by gale winds, but extra
observations and model guidance will build confidence in Friday's
conditions. Conditions are forecast to improvoe through the weekend,
although some amount of steep seas will continue through Saturday.
Another approaching area of low pressure may bring more strong
southerly winds early next week. -TAD
&&
.BEACH HAZARDS...Updated 230 PM Wednesday December 27, 2023...Large
breaking waves are expected to continue through at least Thursday,
which will create dangerous conditions along and within the surf
zone, and could inundate beaches and low lying shorelines.
Increasing the hazards of these breaking waves is the occurrence of
King tides. These very high tides peaked early Monday but will
continue higher than normal through Thursday. So far the tides have
come in 0.3' to 1.2' higher at Port Orford and Charleston
respectively. While there still likely won't be coastal flooding,
this does increase the chance just a little more; and so some low
lying areas especially around Coos Bay may see high water from tidal
overflow combined with the action of the high surf.
Regarding high surf, the high surf advisory has been upgraded to a
High Surf Warning through Thursday. Large breaking waves of 20 to 25
ft are expected through this afternoon. With the arrival of a very
heavy southwest swell, seas will build and this will lead to
dangerously large breaking waves of 25 to 35 ft tonight into
Thursday. This high surf action will increase the inundation of
beaches and increase the risk of beach erosion, especially when
combined with the effects of King tides. /BR-y
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...High Wind Warning until 7 PM PST this evening for ORZ029>031.
Wind Advisory until 7 PM PST this evening for ORZ029>031.
High Surf Warning until 10 PM PST Thursday for ORZ021-022.
Wind Advisory until 7 PM PST this evening for ORZ024>026.
Wind Advisory from 7 PM Thursday to 7 PM PST Friday for ORZ026.
CA...High Wind Warning until 7 PM PST this evening for CAZ081.
High Wind Warning until 7 PM PST this evening for CAZ084-085.
Wind Advisory until 7 PM PST this evening for CAZ084-085.
PACIFIC COASTAL WATERS...Gale Warning until 10 PM PST this evening
for PZZ350-356-370-376.
Hazardous Seas Warning from 10 PM this evening to 4 PM PST
Thursday for PZZ350-356-370-376.
&&The national radar mosaic for the moment the first event began.
2 high surf. Local standard time, as filed.
The Point Saint George buoy (46027) and the Umpqua Offshore buoy (46229) reported swell sufficient to generate high surf. Port Orford reported heavy surf. Surf heights reached 25 to 35 feet, highest on the morning of 12/27.
The Point Saint George buoy (46027) and the Umpqua Offshore buoy (46229) reported swell sufficient to generate high surf. Port Orford reported heavy surf. Surf heights reached 25 to 35 feet, highest on the morning of 12/27.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Oregon in 2023Every state in 2023This day in weather historyWarnings in Oregon, December 2023
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: 1151814, 1151815.