Tracking flooding concerns as we wrap
up with the 2022 year and head into
the new year with multiple watches,
warnings, advisories all out for
storm systems #2 and three in a series
that's been affecting northern and
Central California throughout the week,
we have a winter storm watch in effect
for Thursday night through Saturday night.
This is going to be a bigger part
of the storm cycle,
with one to five feet of new snow
expected and very gusty winds
up to 100 mph over the ridges.
Difficult travel will continue
because we still have this winter
weather advisory in place Thursday
morning through Friday morning
with three to 12 inches of snow,
difficult travel and changing snow levels.
That's gonna be a big part of this
weather story for the next couple of days,
primarily because we're going to
expect excessive rainfall and runoff
with rain in the higher elevations.
That's going to mean all that water
flows down into the valley with rivers,
creeks and streams getting very high and
flood prone areas that seeing a lot of water.
Crisis storms #2 and three,
like I said on the way from the Pacific,
associated with this big plume of
moisture in our atmospheric rivers
that keep coming even into next week.
Here's storm, our storm for Thursday,
just now approaching the coast and it
will be a lighter storm with lighter showers,
snow level rising,
the higher impact day Friday into Saturday,
moderate to heavy rain,
shifting snow level.
We get a break on Sunday,
which will be great because we
need that water to kind of flush
through the system before more.
Atmospheric rivers head our way next week.
Valley flooding, a potential,
as well as some localized roadway and St.
flooding.
When we're using our wipers,
we gotta use our headlights. That's the law.
And turn around. Don't drown.
Also for the Sierra near whiteout conditions,
major travel delays, Rd.
closures possible and chain controls.
Travel will be highly discouraged,
especially by Saturday.
Part of the time.
On Thursday we'll find those delays.
The rain just moving in overnight,
lighter showers to start us off.
Through the day with our snow level
pretty average about 4500 to 5000 feet.
But then as the warmer part of the
storm starts to arrive later in the day,
after a brief break during the
middle of the day,
that's going to push that snow line up.
It will also deliver those
higher rainfall totals.
But even that this first part of the
storm isn't going to be that impressive,
with rain only about 1/4 of an inch to
1/2 an inch for the valley and the foothills,
and for our snow totals also
on the lower end,
about an inch to five inches.
The lower elevations closer to about
12 inches for the higher elevation.
But Sean Deguzman from the Department
of Water Resources saying even
though December is delivering,
we need to keep these storms
going through January and
February, but hopefully the winter stays wet.
That's what everyone's hoping for.
But by the time we get to April 1st when
we have our peak snowpack and we get we,
you know we kind of turn
the door towards the spring,
we'll see how conditions are at that point.
So talking about those snow totals.
And where we stand right now for April 1st,
when Sean was talking about,
that's where our real barometer is for
how much water will have it providing
1/3 of the water for the state.
Currently, we're at 40 to 60% of average.
That's why we need to keep
this storm cycle going.
But if we look at just the average to date,
we're at 130 to almost 200% of average.
That's going to put us
at a statewide average of
162%. And we've got a lot more on the way.
Rain totals also starting to come up.
We were starting to get
dig into some deficits.
Here, especially throughout Northern
California, closer to about 5,
almost 6 inches below normal.
Now we're starting to chip away at that.
We're pretty close to average for
Sacramento and San Francisco,
but Stockton and Modesto about an inch and
1/2 to over 2 1/2 inches ahead of where
we should be at this point in the season.
Just looking at one
particular monitoring site,
Sacramento executive or total so far
for December 4.69 inches of rain.
Normally we have just under 3 inches of rain.
The most we saw this month in
a 24 hour period was back on.
December 3rd one,
we had over an inch and 1/2 of rain
and we've got more weather that could
provide something in that range there
of about an inch to three inches
of rain and about 24 to 48 hours.
So rain is going to be on the
higher impact scale here.
Snow,
moderate wind as well travel
extremely difficult and flooding is
starting to become a bigger concern.
Now I want to make it very clear again,
we have plenty of capacity for our
reservoirs sitting at 30 to 32% for Shasta,
Oroville and Folsom.
And we're looking pretty good
for new Milonas and Don Pedro at
25 to 53% of capacity.
The key here is they are starting
to show some moderate rises and
we'll see a lot more of that moving
into the end of the work week
and into the holiday weekend,
primarily because of what's happening
with that snow line to Thursday.
Again,
this starts off with a great snow
line close to about 4500 to 5000 feet.
Warmer air works than overnight
Thursday into Friday.
That's gonna bump up that snow
line above the passes,
meaning rain on top of snow.
It continues through Saturday morning.
It's not until Saturday evening that we
start to see that snow line dropping,
putting less pressure on everything
downstream from the higher elevations.
We get a break on our Sunday forecast,
but we'll gear up for a wet
week again next week.
So storm system #3 is going
to be the bigger of the two.
That will wrap us up for this week.
With the snow and impacts being changed,
travel and snow level changes.
We'll pick up 12 to 30 inches of
snow north of Hwy. 50. South of Hwy.
5048 to 60 inches of snow,
rain totals a lot more impressive as well.
One to four inches of rain possible
in the valley towards the coast.
And look at this number of Grass Valley,
7 1/2 to 10 inches of rain.
They've already got sandbagging
stations out for parts of Placer County,
Nevada County, even Sacramento County,
preparing for those flood prone areas
to try to prevent a lot of that water
from intruding on people's property.
It's going to be breezy,
but not as windy. The storm system #1,
but we are expecting that moderate to
heavy rain and more runoff expected,
especially with those high rainfall
amounts in the foothills and the Sierra.
We're going to continue to lean
wetter into next week's forecast.
And you can see with our snow level changes,
this is really part of the pressure
that we're talking about for some
of those smaller tributaries.
But not only that are rivers as well.
Thursday morning we got that
snow line at 4000 to 4500 feet,
well below the passes,
kind of the caveat to that
though is with that.
Chain controls very low in elevation.
It makes for some slow going
all the way up the hill.
Now during the day we start to see that
come up above the passes and travel
will be a bit smoother with rain.
It's just the other side of that is we run
the risk of higher flood issues as well.
Saturday afternoon,
we're still pretty high there,
but it comes down pretty quickly
during the evening and that'll get
us to those snow levels closer
to about 5000 feet again by
Saturday evening into early Sunday.
Our five day forecast is on and off,
rain and snow for the high country and
we'll see the rain as well for the foothills.
We're not expecting much in the way
of really low snow for any of these
systems coming through with Sunday for
New Year's Day being a dry day forest,
same for the coast,
a lot of rain and then we'll dry out on
Sunday right back to the active weather.
Want to hit on the potential
for river flooding here?
And I've got it zoomed into
a couple of the locations,
particularly for the Somnus River
and then for the Sacramento River.
We're expecting Colusa,
Tisdale and Fremont Weir to all be
flowing by the time we get to Saturday.
And one area in particular is going to
be Consumnes river at Michigan Bar.
You can see it actually gets to the
forecast of above flood stage by
late on Saturday into early Sunday,
cresting at 13.7 feet.
So that puts us just below,
just above our flood stage,
but not quite to a record set back in 1997.
Eighteen .5 feet,
many of us remembering what that was like.
So again,
we are going to be leaning wetter
into our long range forecast with
multiple atmospheric rivers pulling
through in the Pacific and wet end
to 2022 heading into next week.
You can see we get the after that break
on Sunday, Monday, Tuesday, Wednesday.
We're still looking at decent.
Flow coming in from the Pacific
and even Thursday into Friday we've
got more atmospheric rivers than a
nice flow of moisture coming in.
It's just watching the flood risk
grow in this 10 day forecast as
multiple weather systems continue to
affect us all the way into next week.