Clearing skies and cold dry air combined to bring freezing temperatures to the southern Oregon coast.
Every event with a place to put it; 1 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.
Clearing skies and cold dry air combined to bring freezing temperatures 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 Feb 12, 7:37 PM PST, 2 hours 23 minutes earlier.
Area Forecast Discussion
National Weather Service Medford OR
737 PM PST Mon Feb 12 2018
.DISCUSSION...High pressure's in charge tonight, and clear and cold
conditions are expected. The forecast is on track, and no changes
have been made. Tomorrow will feature warmer temperatures, with
readings 5 to 10 degrees above today's high temperatures. Skies
will be sunny, and it will be one of the warmest days for the next
week+, so take advantage if you're looking for that kind of
weather.
Please see the previous discussion below for details on a system
arriving Wednesday, similar to Sunday's system with low snow levels,
and a potentially very cold pattern this weekend with low
elevation snow possible again.
&&
.AVIATION...13/00Z TAF CYCLE...VFR conditions will prevail through
Tuesday, except for patchy late night through early morning IFR
cigs/vsbys in low clouds and fog over the west side valleys. IFR
conditions are forecast for KRBG and around, but not at, KMFR.
&&
.MARINE...Updated 800 PM PST Monday 12 Feb 2018...Post-frontal
northerly winds will remain at advisory strength into Tuesday
morning with steep seas. Conditions will improve briefly Tuesday
afternoon. Another front will slide by the area early Wednesday
morning bringing another round of increased northerly winds and wind
driven seas into Wednesday night. High and steep seas are expected
north of Cape Blanco during Wednesday night after the front moves
through.
A thermal trough will redevelop Thursday into Saturday. This will
increase northerly winds south of Cape Blanco with advisory
conditions likely. The 00Z Wave watch bulletins continued to trend
higher with a NW swell train in the 10 to 15 foot range with a
period of 12 seconds Sunday into Monday with multiple storm systems
expected to move in from the Gulf of Alaska. -FB
&&
.PREV DISCUSSION... /Issued 250 PM PST Mon Feb 12 2018/
SHORT TERM...Tonight through Thursday Night...Current Satellite
imagery is showing mostly clear skies around southern Oregon and
northern California. A few clouds do exist around the south and
east portions of Modoc and Lake Counties. Temperatures will be
pretty cold for one more night with freezing conditions possible
across portions of the Coos and Douglas coasts. A freeze warning
has been issued for those areas (see NPWMFR for details).
Additionally, frost may be possible a bit further south on the
coast tonight and have issued a frost advisory for those areas
(also see the NPWMFR for details).
Tuesday will show a brief return to normal temperatures and
overall dry weather before a cutoff low is poised to arrive on
Tuesday night into Wednesday. This system will be similar to the
one that was seen Sunday. The current thought is that snow levels
will be about 2000 to 3000 feet across all of southern Oregon and
northern California. But any shower could bring snow levels down
locally and another trace of Rogue Valley snow can't be ruled out.
Precipitation amounts will be quite light with another 3 to 6
inches possible in the Cascades above 3500 feet and up to 2 inches
possible from 2000 to 3500 feet. Showers will continue into early
Thursday morning before dissipating and revealing another mostly
clear, albeit cool, day.
LONG TERM...Fri 16 Feb through Mon 19 Feb 2018...A long wave
ridge will retrograde from between 130W and 140W to between 140W
and 150W during the extended period. This will lead to a pattern
change during this interval.
The current pattern will continue into the extended period, and the
ridge will be dominant on Friday between short waves. Expect dry
conditions for Friday.
The next short wave will move in Saturday as the ridge retrogresses
to between 140W and 150W. This will allow the short wave to dig into
the Pacific Northwest Saturday into Sunday, and this is when the
pattern will transition to a cooler and wetter regime with periods
of gusty winds.
Both the 12/12Z GFS and the 12/12Z EC solutions push a front onshore
Saturday, but the EC brings in more widespread precipitation, at
least initially. Showers will be fairly widespread Sunday as a
short wave moves through the area. The GFS solutions diminishes
activity Monday as the short wave moves out to the east and
southeast. The EC locates the short wave farther west over the CWA,
so it also holds on to the showers a bit longer. Still, activity is
less widespread than Sunday.
The main concern Sunday into Monday will be the possibility of low
level snow with a cold trough overhead. Snow levels look to be
around 1500 feet during the day Sunday, dropping to around 800 feet
Sunday night and 200 feet Monday. It is too far out to forecast
amounts, but this situation will be monitored as it evolves. The
picture should become clearer later this week.
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...Frost Advisory until 9 AM PST Tuesday for ORZ021-022.
Freeze Warning until 9 AM PST Tuesday for ORZ021.
CA...None.
Pacific Coastal Waters...Small Craft Advisory until 10 AM PST Tuesday for
PZZ350-356-370-376.
Hazardous Seas Warning until 10 AM PST Tuesday for PZZ370-376.
NSK/JRS/JRSThe national radar mosaic for the moment the first event began.
1 frost/freeze. Local standard time, as filed.
Reported low temperatures ranged from 24 to 34 degrees.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Oregon in 2018Every state in 2018This day in weather historyWarnings in Oregon, February 2018
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: 730408.