A strong, cold, slow-moving low produced heavy snow as it moved southeast from the Gulf of Alaska into Oregon then northern California.
Every event with a place to put it; 8 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 strong, cold, slow-moving low produced heavy snow as it moved southeast from the Gulf of Alaska into Oregon then northern California.
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 Feb 26, 9:41 PM PST, 19 minutes earlier.
Area Forecast Discussion
National Weather Service Medford OR
941 PM PST Sun Feb 26 2023
.DISCUSSION...Another period of wet, wintry weather will affect northern
California and southern Oregon starting tonight. A substantial
frontal system (an occlusion) will approach the coast overnight into
Monday morning.
This will bring a period of hazardous winds and periods of rain to
the Oregon Coast south of Bandon, with sustained southerly wind
speeds of 40 to 50 mph likely. Gusts of up to 65 mph are possible,
with the highest winds affecting Cape Blanco. These winds are
expected to decrease by 7 am Monday. A High Wind Warning is out to
highlight these hazardous winds. Total precipitation quantities for
the coast of about 0.75 inches forecast north of Bandon and an inch
or more at Bandon and southward through Monday.
A period of very heavy snowfall is expected in the Coast Ranges and
into portions of Siskiyou County, especially the Mt. Shasta region,
during the wee hours of Monday morning, lasting through at least
around noon. Additional snowfall, albeit lighter, will occur for
much of the remainder of the area, though once again it's not a
guarantee. Some locations (like here in the Rogue Valley) could get
completely missed due to potential downslope (south) flow associated
with the front. Even so, snow levels will be down to as low as 500
feet Monday morning and we want to make sure we're not caught
offguard. Please take a look at the multiple Winter Weather
headlines we have in effect (warnings and advisories) at WSWMFR for
specific timing and amounts for your location. It does appear there
will be a several hour period of 1-2"/hour snowfall rates that could
significantly impact I-5 near and south of Weed Monday morning.
Please check road conditions before venturing out.
Eventually, precipitation will become more showery behind the front
Monday afternoon and snow levels will rise some, probably to around
1500 feet or so. This should allow for melting of snow on roadways
in most west side valley locations, but elevations above 1500 feet
could still see some road snow, especially where showers are most
persistent. This is most likely over western Siskiyou County and the
SW Oregon Coast Ranges. Over the East Side, it will get windy too
with the front and with some light snow, there may be blowing and
drifting snow at times.
Even though there may be a break for some Monday afternoon, we do
expect low elevation snow potential to continue Monday night into
Tuesday as multiple disturbances rotate around a deep cold core
upper level low. Snow levels are expected to once again fall down to
around 500 feet, so many western valleys could have accumulating
snow. That's the reason, we are continuing the winter weather
products through at least Tuesday. The system looks to move away
from our area Tuesday night, with a brief period of mild conditions
following. -Spilde/TAD
&&
.AVIATION...27/00Z TAFs...A front has moved east of the area and
scattered showers continue in its wake, mainly from the Cascade
crest west. Brief MVFR ceilings and visibility can be expected in
any of these showers through the evening, otherwise, conditions will
be VFR. Mountain obscurations will continue on west facing slopes.
Another front brings widespread precipitation and gusty south winds
by tomorrow morning. LLWS is possible as the front approaches with
the highest likelihood near KMFR, so that was included in the TAF.
Confidence in that is lower elsewhere. Conditions will deteriorate
rapidly as the front moves inland tomorrow morning with rain below
roughly 1000 feet MSL and snow above that. Visibilities and ceilings
will be worst (possibly LIFR) where snow falls. -Wright
&&
.MARINE...Updated 800 PM Sunday, February 26, 2023...A strong front
will bring south gales to the waters late this evening into Monday
morning. This will be followed by a secondary front Monday afternoon
and evening that will bring another round of gales, this time from
the southwest to west. The gale warning has been extended through
Monday evening to cover this. While not all areas are expected to
get sustained gales with this second front, portions of all waters
likely will, and there is enough uncertainty regarding the exact
orientation and intensity of this front as it moves through to err
on the side of caution and include all areas in the gale warning.
Conditions will improve Tuesday, but additional fronts are expected
next week into the following weekend. -Wright
&&
PREV DISCUSSION... /Issued 255 PM PST Sun Feb 26 2023/
SHORT TERM... After a brief break, Winter Weather headlines return
for portions of southern Oregon and northern California tonight
through Tuesday. The front is currently reaching eastern portions
of the area, and that is where snow is still falling.
The next system Monday will be a colder, windier, and wetter system.
Colder air and a showery air mass will follow Monday night into
Tuesday night. The latest update has been an issuance of a Winter
Weather Advisory for Monday morning in parts of Jackson County, and
this includes Ashland and Butte Falls. As with today, heavier showers
could bring snow to areas lower than these areas, but 1 to 3
inches is possible here. The end time on winter weather products
has been extended through Tuesday afternoon, with lighter
lingering snow showers expected Tuesday night.
As related in the previous discussion, similar to our most recent
event, models are focusing the heaviest precipitation for Curry,
Josephine, and western and central Siskiyou County, secondarily for
Coos, Douglas, Jackson, and western Klamath counties. Snow levels
look to bottom out around 1000 feet Monday morning and nudge up to
around 1800 feet by the end of the afternoon with day-time heating.
The trajectory and strong winds anticipated with this next system
strongly suggests another heavy snow event for the Mt Shasta region,
but also for the Kalmiopsis Wilderness area of eastern Curry/western
Josephine Counties and western Siskiyou County where another 14 to
20 inches of snow is expected. Additionally, the Illinois Valley
area from roughly Hayes Hill southward is expected to see a
significant amount of snow with 8 to 10 inches in the current
forecast. Confidence was high enough for these areas to see
significant winter impacts that we have upgraded the Winter Storm
Watch to Warnings for these areas. We decided hold off on the
remainder of the Watches to see how far south the models trend with
the focus of precipitation. The pattern of this storm typically
favors lesser amounts along the Cascades and Douglas/Jackson County
foothills. So with lesser confidence in these areas, will let future
shifts re-evaluate over the coming forecast cycles. With snow levels
starting so low late Sunday night into Monday morning, it's likely
that west side valley floors will see some accumulating snow.
Currently, the forecast supports around 2 to 4 inches across the
Rogue Valley and Grants Pass area, as well as the Shasta Valley.
In addition to the snow impacts with the Monday system, there are
strong winds to consider, especially in the Shasta Valley, east of
the Cascades and even for the southern end of the Rogue Valley.
While 700 mb winds don't currently support warning level winds, they
certainly support advisory level, and maybe even high-end advisory
level wind speeds. For areas that will be covered under winter
weather products, any additional wind headlines will likely be
wrapped into those products. It should be noted that strong winds
coupled with heavy snowfall could lead severely limited
visibilities, particularly in the Shasta Valley and east of the
Cascades. Strong southerly flow could also lead to downsloping
effects for the Rogue Valley, which would tend to lower
precipitation amounts and also contributes to the lower confidence
in snow amounts for that particular area.
Active weather will continue for much of the day Monday, though
there will be a relative lull in precipitation intensity late in the
day Monday and winds will diminish during that time as well. Snow
levels look to fall back to down to valley floors Monday evening and
overnight, and with ongoing precipitation, winter weather impacts
are expected through Tuesday. The aforementioned lingering light low
level snow showers will taper off Tuesday night into Wednesday
morning. -DW
LONG TERM... High pressure will provide a break later Wednesday into
Thursday. Model agreement has increased relating to a very weak
front late Thursday into Thursday night with up to a few inches of
new snow possible for the Cascades, and snow levels forecast
around 3000 feet. Another break is most likely on Friday ahead of
the next unseasonably cold frontal system next weekend. -DW
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...Winter Weather Advisory from 4 AM Monday to 4 PM PST Tuesday for
ORZ029>031.
High Wind Warning until 7 AM PST Monday for ORZ021-022.
Winter Storm Warning until 4 PM PST Tuesday above 1500 feet for
ORZ021-022-024.
Winter Storm Warning from 1 AM Monday to 4 PM PST Tuesday above
1500 feet for ORZ023-025.
Winter Weather Advisory from 4 AM Monday to 4 PM PST Tuesday
above 500 feet for ORZ023.
Winter Weather Advisory from 1 AM Monday to 10 AM PST Tuesday
below 1500 feet for ORZ024.
Winter Storm Warning from 4 AM Monday to 4 PM PST Tuesday above
2000 feet for ORZ026.
Winter Weather Advisory from 4 AM Monday to 10 AM PST Tuesday
below 2000 feet for ORZ026.
Winter Storm Warning from 4 AM Monday to 4 PM PST Tuesday for
ORZ027-028.
CA...Winter Storm Warning from 1 AM Monday to 4 PM PST Tuesday for
CAZ080.
Winter Storm Warning from 4 AM Monday to 4 PM PST Tuesday for
CAZ081.
Winter Weather Advisory from 4 AM Monday to 4 PM PST Tuesday for
CAZ081.
Winter Storm Warning from 4 AM Monday to 4 PM PST Tuesday for
CAZ082-083.
Winter Weather Advisory from 4 AM Monday to 4 PM PST Tuesday for
CAZ084-085.
PACIFIC COASTAL WATERS...Hazardous Seas Warning until 10 PM PST this
evening for PZZ350-356-370-376.
Gale Warning until 10 PM PST Monday for PZZ350-356-370-376.
&&
MAS/TAD/CCThe national radar mosaic for the moment the first event began.
8 heavy snow. Local standard time, as filed.
The national gridded snowfall analysis indicated snowfall of 6 to 12 inches at elevations above 1500 feet, and 1 to 5 inches at lower elevations.
The national gridded snowfall analysis indicated snowfall of 12 to 30 inches at elevations above 1500 feet, and 1 to 8 inches at lower elevations. Gold Beach reported 8 inches.
The national gridded snowfall analysis indicated snowfall of 8 to 18 inches, except 15 to 30 inches at higher elevations.
The national gridded snowfall analysis indicated snowfall of 6 to 12 inches at elevations above 1500 feet, and 2 to 6 inches at lower elevations.
The national gridded snowfall analysis indicated snowfall of 7 to 15 inches.
The national gridded snowfall analysis indicated snowfall of 6 to 12 inches at elevations above 2000 feet, and 2 to 7 inches at lower elevations.
The national gridded snowfall analysis indicated snowfall of 8 to 18 inches.
The national gridded snowfall analysis indicated snowfall of 6 to 18 inches.
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, February 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: 1084090, 1084091, 1084093, 1084092, 1084094, 1084095, 1084096, 1084097.