NWS Medford, OR wrote its last area forecast discussion before the first event at Apr 3, 8:33 PM PST, 3 hours 28 minutes earlier.
Area forecast discussion, Apr 3, 8:33 PM PST, 3 hours 28 minutes before
Area Forecast Discussion
National Weather Service Medford OR
933 PM PDT Sun Apr 3 2022
.DISCUSSION...The forecast has been updated to remove both mention
of ridge level freezing rain on Monday and also the slight chance
of thunderstorms on Monday from Douglas County. Otherwise, the
forecast is on track with light rain now beginning to spread into
Coos and northern Douglas counties.
A cold front tonight through Monday and following surface trough
Monday night into Tuesday will provide windy, wet, much cooler
conditions. Precipitation amounts will be highest late tonight
through Monday morning with a storm total of around three quarters
of an inch to two inches expected for the coast and Cascades, a
quarter of an inch to three quarters of an inch for west side
valleys, and a tenth of an inch to a half inch for most of the
east side. Snow levels around 5000 to 6000 feet overnight will
fall to around 4500 feet on Monday with the bulk of the 6 to 12
inches of snowfall occurring that is expected for the Cascades
from the Lake of the Woods vicinity northward. Light snow showers
of around 1 to 3 inches for that area will linger Monday night
into early Tuesday with the snow level falling to around 3000
feet.
It will remain cooler than normal with decreasing clouds Tuesday,
then a very strong warm up will follow at mid-week. A westerly
flow pattern is likely at the end of the week with most of the
energy from a series of fronts aimed north of our area.
&&
.AVIATION...04/00Z TAFs...The main concern will be low level wind
shear this evening and lasting almost until the end of the TAF
period for Roseburg, Medford and Klamath Falls. Along the coast,
including North Bend will be a close call, but based on the latest
guidance stronger winds are expected to surface at the same time
winds aloft increase, so left it out for now, but later shifts will
need to take another look at this. if nothing else, strong winds
approaching 40 kts is a possibility at North Bend tonight into early
tomorrow morning. Strong surface winds are also possible at Klamath
Falls Monday afternoon with gusts up to 40 kts.
Ceilings are expected to remain VFR along the coast into early this
evening, then lowering to MVFR around 2z and remaining there until
the end of the TAF period. However it's possible they could lower to
IFR for a brief period late tonight into tomorrow morning in heavier
precipitation.
Inland west of the Cascades, VFR ceilings/visibility will continue
into this evening, lowering to MVFR north of the Umpqua Divide and
west of Medford later this evening, with MVFR ceilings at Medford
and Klamath Falls late tonight. -Petrucelli
&&
.MARINE...Updated 800 PM PDT Sunday 3 April 2022...South winds will
continue to increase as a front moves towards the waters this
evening. Winds are then expected to peak later this tonight, before
shifting southwest and gradually diminishing as the front moves
onshore early Monday morning. Gale force winds are expected later
this evening into early Monday morning. The general consensus
suggest gales will arrive a little later and affect areas further
south, mainly from Gold Beach north, and adjustments were made to
the Gale Warning. Fore more details, please see MWWMFR.
In addition, a rather large long period northwest swell will build
into the waters beginning late night and persist through Tuesday
night. These waves will also create very high surf along area
beaches. Current forecasted surf height of 18 to 23 feet which will
keep it in high surf advisory criteria. However, this will need to
be watched carefully. -Petrucelli
&&
.PREV DISCUSSION... /Issued 456 PM PDT Sun Apr 3 2022/
SHORT TERM...Through Tuesday night...Satellite imagery shows
increasing clouds across the forecast area, ahead of a significant
frontal system due to bring rain and mountain snow to the area
tonight through Monday. Mountain wave clouds can be observed in
the visible imagery, and this indicates increasing winds aloft.
Even though this front will deliver very beneficial rainfall and
mountain snow to the area, there will still be some weather
hazards to be aware of. Hazards with this front include strong
winds east of the Cascades, moderate to heavy mountain snow
(favoring the Cascades), and eventual high surf at the coast.
First, wind. Winds will increase tonight along the coast and in the
high terrain. Gusts to 50 mph are expected along the immediate
coast, especially in exposed areas and at the headlands. Gusty winds
will expand inland Monday morning, becoming gusty over higher
terrain west of the Cascades and east of the Cascades. We've issued
a Wind Advisory for mainly higher terrain areas of Josephine,
Douglas, and Eastern Douglas Counties for early Monday morning, but
some gusty winds may occasionally surface in valleys like the Umpqua
or Illinois. Statistical guidance and the latest suite of high
resolution raw model data supported this. We've also expanded the
Wind Advisory east of the Cascades to include Klamath Falls, based
on the latest model data. Winds will be strongest and last the
longest east of the Cascades, from Monday morning through Monday
night.
Second, snow. We are expecting to see 6 to 12 inches of snow in a 12
hour period in the High Cascades from tonight through Monday
morning. Additional snow is expected Monday afternoon, but impacts
to roadways should diminish some in the afternoon. Thus, the Winter
Weather Advisory focuses on late tonight into Monday morning, with
the heaviest snow expected Monday morning. Snow levels should
generally be 5000 feet and higher, though some snow is possible down
to 4000 feet late Monday afternoon as precipitation rates diminish.
There is some potential for snowfall in places like Chemult east of
the Cascades, but accumulations should be limited to a few inches.
Last but not least, rainfall. Latest model data suggest this
Atmospheric River (AR) will be of moderate intensity. 1 to 2 inches
of precipitation is expected at the coast and in the Cascades, with
a quarter to half inch of rainfall in valleys west of the Cascades.
High resolution model data even suggests a quarter inch of rainfall
in some valley places east of the Cascades like Klamath Falls. This
of course would be beneficial given the ongoing severe drought.
Some showers are possible Tuesday, and winds will be diminishing, so
weather impacts on Tuesday will decrease across the forecast area.
Of additional importance, Monday night and Tuesday night will both
feature cold temperatures, likely colder Tuesday night because of
less cloud cover, so agricultural interests should stay tuned to
the forecast for your location and take any necessary precautions.
LONG TERM...Wednesday, April 6 through Sunday, April 10... On
Wednesday a rapid warmup is expected, as a ridge builds to a peak.
Dry and warm conditions will prevail. Afternoon highs are expected
to be about 10-15 degrees above normal from Klamath Falls west. Weak-
to-moderate east flow flow should exist across the region, drying
out the mid-slopes and ridges. We expect the recent moisture will
not be enough to offset the drying in west side valleys, so fog is
not included in the forecast.
Thursday the ridge begins to push east but, not before another day
of hot temperatures and dry conditions. Afternoon highs should be 20-
25 degrees above normal for the whole region, and it is likely going
to feel more like early June. And although the weak east flow may
still exist in the morning, the general wind should gradually turn
onshore from the northwest. As a result we aren't expecting MinRHs
to drop any lower than on Wednesday; if anything, they may even be a
few points higher for areas west of the Cascades.
Friday, signs of an approaching trough should begin to develop as
the general flow strengthens from the WNW, cooling the region, and
cirrus tries to invade the celestial dome. A front at the leading
edge of the trough will bring some low end rain chances to Coos and
Douglas County late Friday night, but the front is generally
expected to fall apart against the lingering dry air mass. This
decaying front may bring some slightly stronger afternoon west winds
to the Cascades and east on Friday, and then again a bit stronger on
Saturday.
To start next week, rain chances increase across the area, as the
first in what could be a series of troughs bring moist, cool air
into the region. CPC's 8-14 day forecast from April 2, calls for a
60-70% chance for below normal temperatures and a 30-40% chance for
above normal precipitation for April 10-16. -Miles
&&
.MFR WATCHES/WARNINGS/ADVISORIES...
OR...High Wind Warning from 2 AM to 11 PM PDT Monday for ORZ030-031.
Wind Advisory from 5 AM to 11 PM PDT Monday for ORZ029>031.
Winter Weather Advisory from midnight tonight to noon PDT Monday
for ORZ027-028.
Wind Advisory from 1 AM to 9 AM PDT Monday for ORZ023>025.
High Surf Advisory from 11 PM Monday to 5 PM PDT Tuesday for
ORZ021-022.
CA...High Wind Warning from 2 AM to 11 PM PDT Monday for CAZ085.
Wind Advisory from 5 AM to 11 PM PDT Monday for CAZ084-085.
Pacific Coastal Waters...
Small Craft Advisory until 11 PM PDT Monday for
PZZ350-356-370-376.
Gale Warning until 5 AM PDT Monday for PZZ350-356-370.
DW/BPN