Air Resources Laboratory banner image
Air Resources Laboratory web site National Oceanic and Atmospheric Administration (NOAA)

or discuss

Office: MFR

FXUS66 KMFR 231609

Area Forecast Discussion
National Weather Service Medford OR
909 AM PDT Sat Jun 23 2018

.UPDATE...Satellite imagery shows clouds slowly clearing in the
Umpqua basin. Expect sky cover to burn off quicker today than
yesterday, likely by early afternoon. Today will be a warm day in
Brookings, expected to reach into the 80s early this afternoon.
Otherwise, conditions today will be similar to yesterday in most
places. Tomorrow will be the warmest day of the year thus far, and
the million dollar question will be how many places hit 100. Much
depends on the timing of the approaching cold front... high clouds
ahead of the front could prevent some heating, and model guidance
has trended that front approaching slightly quicker. To be clear,
Sunday will still be very hot, but a faster progression of the
cold front could mean that Medford "only" reaches 98 or 99, and
Roseburg only reaches the lower 90s. Otherwise, the current
forecast is on track, see previous discussion for more
information. -McAuley


.AVIATION...For the 23/12Z TAFs...Offshore flow has developed and VFR
conditions are expected for the rest of the TAF period. The
exception to this could be at North Bend. Guidance suggest MVFR cigs
could return to the coast, north of Cape Blanco, including North
Bend later tonight as weak onshore flow is expected. For now went
with MVFR cigs at North Bend later tonight, but later shifts may
need to reevaluate. -Petrucelli


.MARINE...Updated 800 AM PDT Saturday 23 June 2018...The thermal
trough will remain along the oregon coast through the weekend. The
models continue to show stronger north winds and building seas
expanding north during the day, but they do not show them getting
much further north than Bandon this afternoon and tonight. For now
have left the coverage area of the small craft as is in the event
future model runs show stronger winds and higher seas further north.
Later shifts will want to take another look at this.

Meanwhile, very steep and hazardous seas and occasional gale force
gusts are expected south of Gold Beach. A Gale Warning remains in
effect to account for both the expected Gale gusts and the likely
hazardous sea conditions.

The thermal trough pattern will be temporarily disrupted late Sunday
into Monday as an upper level trough moves just north of the area.
Conditions, however, are likely to remain hazardous to small craft
into next week as the upper level trough will maintain tight
pressure gradients and resultant moderate to strong northerly winds.
Very steep wind driven seas look to continue into midweek with the
thermal trough strengthening Tuesday onward. BR-y/Petrucelli


.FIRE WEATHER...Updated 300 PM PDT Friday 22 June 2018...Warmer
than normal temperatures and breezy winds are expected east of
the Cascades for this evening. A thermal trough will setup along
the coast on Saturday. Winds and temperatures will then increase
along the Southern Oregon coast Saturday. The thermal trough will
retreat eastward on Sunday with temperatures increasing about ten
degrees across the region. Sunday will also be the warmest day
with high temperatures 15 to possibly 20 degrees warmer than
average. Daytime humidities will fall to the mid and lower teens
in valleys. Breezy and much cooler conditions are expected Monday
with a marine push in the west side in Oregon.



.PREV DISCUSSION... /Issued 640 AM PDT Sat Jun 23 2018/

DISCUSSION...Today's temperatures should be similar to
yesterday's. However, with northeast winds on the southern coast
remaining in place through the day the Brookings area should see
high temperatures similar to the inland valleys in southern
Oregon with the Chetco effect in force through the day. These
Chetco effect winds will remain in place through the night with
low temperatures only dropping down to the mid to upper 60s in
the Brooking area in from the immediate coast. The deep thermal
trough at the coast that brought the northeast Chetco effect winds
moves inland Sunday, bringing around a 10 degree warmup inland
from today's highs, with high temps in the triple digits south of
the Umpqua divide in the west side valleys. In the Brookings area
the flow will become onshore when the thermal trough moves inland,
with high temperatures being reached probably in the morning.

As the thermal trough continues to migrate east Sunday night a
strong marine push will bring stratus and even fog to the coast
and inland into the coastal range, and with the northeast winds
pushing the stratus and fog there will be areas of drizzle from
the coastal range to the coast. The drizzle should be mostly north
of the Umpqua divide. Temperatures will obviously be much cooler
Monday compared to Sunday in this marine push flow.

A more zonal flow pattern returns Tuesday with the thermal trough
deepening along the coast once again. This will bring gradual
warning into Wednesday. Sven




Pacific Coastal Waters...Small Craft Advisory until 5 PM PDT Monday for PZZ356-376.
     Gale Warning from 2 PM this afternoon to 11 AM PDT Sunday for
     Small Craft Advisory from 2 PM this afternoon to 5 PM PDT Monday
     for PZZ350-370.



Office: PQR FXUS66 KPQR 232041 AFDPQR Area Forecast Discussion National Weather Service Portland OR 140 PM PDT Sat Jun 23 2018 .SYNOPSIS....Upper level high pressure passing over the Pacific Northwest will produce warmer and sunnier weather on Sunday before an incoming front brings cooler and cloudier conditions early next week with a chance of light rain Sunday night and Monday. && .SHORT TERM...Tonight through Tuesday...Water vapor satellite imagery reveals a shortwave trough dropping southeastward across the Inland Northwest and northern Rockies this afternoon. Shortwave ridging building is currently beginning to build into the Pacific Northwest ahead of a surface low pressure system spinning in the Gulf of Alaska. This upper level ridging will traverse the region tonight and Sunday. This should lead to considerably fewer marine clouds on Sunday morning and temperatures should warm into the mid to upper 80s on Sunday. The warmup will be short lived, however, as the aforementioned surface low pressure will push a weakening front into the area Sunday night and Monday. This will likely bring at least some light rain to our coastal zones during this time with a decent chance at least some of the rain will hold together enough to impact portions of the Willamette Valley and Cascades. The increased moisture, clouds and cooler temperatures aloft may result in temperatures dropping nearly 20 degrees on Monday when compared to Sunday afternoon's readings. Northwesterly onshore flow underneath zonal flow aloft should keep temperatures near average for the date on Tuesday with afternoon sunshine making a return. /Neuman .LONG TERM...Tuesday night through Saturday. Tue night both the 12z GFS and 12z Euro show a shortwave ridge start to move through the area. This will keep an onshore flow into the area, which will keep the area on the cooler side for the first part of the week. As Wed night approaches, a shortwave trough starts to come on shore,this shortwave doesn't look to increase PoPs. However, a much deeper trough will enter the area starting around Fri morning, which will slowly start to bring PoPs up as the trough moves through Sat. For the weekend it should be noted that the GFS has a much deeper trough entering into the area, while the Euro shows the trough being far shallower, but still bringing a chance for precip into the start of next weekend. /42 && .AVIATION...VFR prevailing through Sun a drier northerly flow develops in the low levels. However the north Oregon and south Washington coast will have MVFR cigs tonight but should dissipate early Sun. KPDX AND APPROACHES...VFR conditions prevailing next 24 hours with NW winds 6 to 10 kt through evening then easing. mh && .MARINE...High pressure over the NE Pac, with thermal low pressure over northern California and southern Oregon continues through the weekend and most of next week. The high will strengthen through the Sun, bringing increasingly gusty northerly winds to the waters. Expect gusts to 25 kt over the central OR waters each afternoon and evening over the weekend and through the first half of next week. The exception looks to be Mon, when another weak surface trough temporarily weakens the NE Pac high again. Seas remain around 2 to 4 ft through the weekend, ramping up to 5 to 7 ft by early Monday. Pyle && .PQR WATCHES/WARNINGS/ADVISORIES... OR...None. WA...None. PZ...Small Craft Advisory for winds from 2 PM this afternoon to 5 AM PDT Sunday for Waters from Cascade Head to Florence OR from 10 to 60 NM. Small Craft Advisory for winds from 2 PM this afternoon to 11 PM PDT this evening for Coastal waters from Cascade Head to Florence OR out 10 NM. && $$ Interact with us via social media: This discussion is for Northwest Oregon and Southwest Washington from the Cascade crest to 60 nautical miles offshore. This area is commonly referred to as the CWA or forecast area.
Office: PDT FXUS66 KPDT 232127 AFDPDT Area Forecast Discussion National Weather Service Pendleton OR 227 PM PDT Sat Jun 23 2018 .SHORT TERM...Tonight through Tuesday...An upper ridge will build over the Pacific Northwest tonight. As such will see decreasing clouds this evening with mostly clear skies overnight. Some smoke from wildfires will pool in north-central Oregon overnight. Conditions will be dry and sunny Sunday with much warmer high temps due to the upper ridge. Again some smoke will affect portions of north-central and central Oregon. A system will move out of the Gulf of Alaska into western Canada Sunday night into Monday. This system will push a cold front across the region between midnight and noon Monday. This front still looks to be mostly dry, except for a few showers over south-central Washington. Winds will increase with and behind the front Monday. A dry westerly flow should persist across the region Monday night into Tuesday. Winds will remain breezy Monday night into early Tuesday, then decrease Tuesday afternoon. Temps are expected to run near or slightly below seasonal Monday through Tuesday. 90 .LONG TERM...Tuesday night through Saturday. Westerly flow will continue Tuesday night through Wednesday with dry conditions and seasonal temperatures. A weak trough of low pressure will move through Wednesday night/Thursday, with cooler temperatures and some breezy winds, mainly through the gorge and out into the lower basin. Another upper level trough is expected to move through Friday and Saturday. Models are in some disagreement on development, strength and position of system, but most likely will produce some scattered showers mainly over the mountains as temperatures remain slightly below seasonal values. 93 && .AVIATION...00Z TAFS...VFR conditions can be expected through the period. Clouds over the mountains will be decreasing with mostly clear skies overnight. Ridge will be building over pacific northwest Sunday with mostly clear skies. Winds will become light, under 10 kts at all TAF sites and remain light through Sunday. 93 && .PRELIMINARY POINT TEMPS/POPS... PDT 54 90 60 78 / 0 0 0 0 ALW 57 91 63 81 / 0 0 0 0 PSC 55 93 63 84 / 0 0 0 0 YKM 53 92 59 81 / 0 0 10 0 HRI 53 94 63 83 / 0 0 0 0 ELN 52 92 61 72 / 0 0 20 10 RDM 44 91 52 77 / 0 0 0 0 LGD 47 85 55 79 / 0 0 0 0 GCD 48 87 55 80 / 0 0 0 0 DLS 57 95 62 77 / 0 0 0 0 && .PDT WATCHES/WARNINGS/ADVISORIES... OR...None. WA...None. && $$ 90/93/93