A quick hitting snow storm dropped heavy snow on some locations in northern California.
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.
A quick hitting snow storm dropped heavy snow on some locations in 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 Dec 7, 9:32 AM PST, 5 hours 28 minutes earlier.
Area Forecast Discussion
National Weather Service Medford OR
932 AM PST Wed Dec 7 2016
.DISCUSSION...A cold start to the morning with the coldest
temperatures so far this season. Low temperatures in the single
digits and near or below zero were common east of the Cascades;
low to mid 20s for the inland westside and low to mid 30s near
and at the coast. High clouds are already advancing into the area
ahead of a warm front and the cloud deck will only thicken and
lower as time goes on. This will slow down the amount of warming
this afternoon for many areas. In fact its likely to remain below
freezing east of the Cascades. The 12z models are slower with the
arrival of precipitation in northern Cal and southwest Oregon.
The GFS and short range his res HRRR are in fairly good agreement
with timing and location of precipitation. The NAM has the leading
edge southwest of our forecast area. Therefore have trimmed back
pops for this afternoon and evening, keeping the best chance in
Northern Cal and extreme southwest Oregon this evening.
A preliminary look at some of the soundings does not show enough
that would convince me to make much if any changes to where we
have a slight chance or change for freezing rain tonight through
Thursday morning. Right now, it looks like the best chance for
freezing rain could end up in some of the deeper valleys in
western Siskiyou County like the Klamath River Basin, Scott
Valley and maybe the northern, western and eastern fringes of the
Shasta Valley. Also portions of Highway 97 north of Chiloquin
could be affected by freezing rain. All of this will be looked at
in more detail this morning and we'll decide if we to upgrade the
the watch to a warning and if so where. -Petrucelli
&&
.AVIATION...07/12Z TAF CYCLE...Most of the west side valleys have
IFR ceilings/fog this morning, but the rest of the area is drying
out with offshore east winds. MVFR ceilings cleared to VFR at KRBG
in the last hour, but this may just allow IFR low cloud/fog to
develop again nearby this morning. All areas should clear to VFR
late this morning or early this afternoon.
A warm front will move into the area this evening and conditions
will deteriorate quickly tonight with MVFR ceilings becoming
widespread. Terrain will become obscured with areas of IFR.
Precipitation will spread from southwest to northeast across the
area with enough cold air for snow from the Cascades eastward. Some
sleet or freezing rain is possible in some of the colder west side
valleys at the start of precipitation before warmer air changes
any mixed precip over to rain. Snow will also gradually transition
to rain for all but the highest peaks on Thursday. -Spilde
&&
.MARINE...Updated 300 AM PST Wednesday 7 December 2016...Light
to moderate east winds are expected today as high pressure slides by
over land. Later today, a warm front moves through and winds shift
to the south and increase. Low pressure then moves by and a cold
front approaches tonight, then shifts through the area Thursday.
Expect a period of gales and steep to very steep seas with this
front. Models show winds gradually easing Thursday night into
Friday, but will likely remain at small craft advisory levels. Seas
during this time frame will build due to large west swells. They'll
reach a peak Friday afternoon or evening at 15 to 22 feet (highest
over the northern waters), then gradually subside by Saturday
morning. Relatively calm conditions from both winds and seas are
expected Sunday. However, the storm track is likely to become active
again next week. -Spilde
&&
.PREV DISCUSSION... /Issued 419 AM PST Wed Dec 7 2016/
DISCUSSION...Wintry weather returns tonight and could pose a
challenge to travel tonight and Thursday.
Overnight radiational cooling has brought temperatures below
freezing across southwest Oregon with frost likely overnight even
at the coast. Low clouds have formed over the Rogue and Illinois
Valleys while at the same time a warm front is spreading high
clouds north into southern Oregon. The main concern is that as the
clouds spread into the region, this would cap the cold air in
place and we may not see a lot of warming. As the warm rain falls
into the pool of cold air, valleys in southwest Oregon and
Siskiyou County could see freezing precipitation this evening.
The Illinois Valley and lower Klamath River Valley appear
favorable due to trapped cold air. Conditions are not as clear cut
in the Shasta Valley as we are also expecting strong winds to
develop this afternoon with the Redding-Medford pressure gradient
of 8-10 mb. The strong SE winds could scour out the cold air.
In addition the south end of Jackson County near Ashland is also
expected to see stronger 10-20 mph winds. The lower elevations of
Ashland could see some freezing precipitation while the higher
elevation may see stronger winds scouring out the cold air.
By Thursday morning, the overrunning of the cold air will spread
into the East side with potential for freezing rain in the Klamath
Basin, the Tulelake Basin and northern Lake County. Since cold air
is much deeper east of the Cascades, most areas will see snow but
we cannot rule out pockets of freezing rain late tonight into
Thursday morning. By Thursday afternoon stronger winds are
expected to surface into the Christmas Valley and parts of Highway
31 between Paisley and Summer Lake could be impacted.
Highs on Thursday will climb into the mid to upper 30s and
possible lower 50s for west of the Cascades and even the east side
could see highs climbing above freezing. After the warm front has
moved through the area, the cold front will follow through on
Friday. The atmosphere will remain unstable with showers
throughout the day into the end of the week.
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...High Wind Watch from Thursday afternoon through late Thursday
night for ORZ030-031.
Winter Storm Watch from late tonight through Thursday afternoon
for ORZ029>031.
Winter Storm Watch from this evening through Thursday morning
for ORZ023>026.
Winter Storm Watch from this evening through Thursday afternoon
for ORZ027-028.
CA...High Wind Watch from Thursday afternoon through late Thursday
night for CAZ085.
Winter Storm Watch from late tonight through Thursday afternoon
for CAZ084.
Winter Storm Watch from this evening through Thursday morning
for CAZ080-081.
Winter Storm Watch from this evening through Thursday afternoon
for CAZ083.
High Wind Watch from late tonight through Thursday afternoon for
CAZ081.
Pacific Coastal Waters...Small Craft Advisory from 10 PM this evening to 4 PM PST
Thursday for PZZ350-356-370-376.
Hazardous Seas Watch from Thursday afternoon through late Friday
night for PZZ350-356-370-376.
Gale Warning from 4 AM to 4 PM PST Thursday for
PZZ350-356-370-376.The national radar mosaic for the moment the first event began.
1 heavy snow. Local standard time, as filed.
A member of the public reported 3.5 inches of snow between 07/1500 PST and 07/1845 PST.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in California in 2016Every state in 2016This day in weather historyWarnings in California, December 2016
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: 665703.