Coast Heat: All-Time April Highs at Newport & Astoria

April 30, 2014

11pm Wednesday…

Today was a scorcher…at least by April standards.  Here are the record high temps set today within our viewing area:

MarkRecordHighTempsMetro

Notice Newport and Astoria Airport both recorded their all-time April high temps.  The Astoria airport records go back to the 1950s.  We didn’t hit a record in the metro area because most of us were around 90 on April 30th, 1998.  Check out the central coast temperatures:

MarkCoast_HotTemps

North Bend hit 91, which I would assume is an April record too, in fact the old record for the day at North Bend is just 72!

Easterly wind was actually a little TOO strong from the middle of town out to the eastside, keeping temps a little lower than I expected.  But that east wind will suddenly drop off tomorrow morning, we’ll be left with a warm air mass.  That should allow temperatures to rise a bit more in the afternoon; thus our high temperature forecast in the upper 80s.  We’ll see how that works out.

A very obvious and dramatic change will occur Friday afternoon/evening as a strong marine push of cooler ocean air moves inland along with a cold front.  It appears we might get a few sprinkles out of that Friday evening.

After that it’s on to 3-4 days of clouds, showers, and cooler than average temperatures; and that includes the weekend.

Chief Meteorologist Mark Nelsen


Fresh Podcast Posted

April 30, 2014

providence-park-snow

 

Brian and I just recorded a podcast early this week.  Find it here:

http://nwweatherpodcast.wordpress.com/2014/04/30/episode-37-winter-recap-and-weather-questions/

 

 


Warm Spell Continues…80s Today

April 30, 2014

Just a quick post with a few record temps.  Everything worked out according to plan today with high temps in the 80s in the western valleys and 80s at the coast too.

As of 5pm it appears that Salem hit a record high of 86 (for April 30th).  Eugene also had a record high of 82 degrees.  Vancouver, Hillsboro and Troutdale didn’t hit a record high.  Here in Portland we hit 83, quite a way from the 90 degree record set in 1998:

MarkWarm_PortlandRecords

Astoria made it to 84 degrees, not just a record for the day but also the WARMEST APRIL DAY ever recorded.

East wind backs off tomorrow, and surprisingly that means a warmer day in the Portland area…more on that later.

Chief Meteorologist Mark Nelsen


The Heat Is On: April-Style

April 28, 2014

80 degree temperatures are on the way, including to the Oregon Coast!  Hard to believe after seeing snow down below 3,000′ this weekend, but it’s coming.  Models have been telling us this for almost a week; so quite a good forecast.

The Highlights This Week

  • Warmest weather so far this year
  • 80s at the Coast Wednesday, maybe for some spots Thursday too
  • 80s in the western valleys of Oregon and SW Washington Wednesday and Thursday
  • Gusty east wind tomorrow through Thursday morning in and near the Gorge.  Gusts could exceed 50 mph tomorrow night and Wednesday.

 

Take a look at the 500mb (~18,000′) chart for Thursday morning; that’s quite a ridge of high pressure centered right on the West Coast!  We haven’t seen that this spring so far.  That blocks all storminess and when it’s in this position we get surface high pressure to our east.  Thus the breezy east wind expected the next few days.  And when the ridge is very “sharp-looking” like this one, we tend to get a nice sharp trough of low pressure down at sea level along or off the coastline.  That’s why in this case the east wind will make it all the way to the beaches.

ecmwf_perfect500mb

How warm (hot) is it going to get?  Models are in excellent agreement that 850mb temps (~4,000′) will be around +16 to +17 over Salem/Portland Wednesday and Thursday.  When you combine that with maximum mixing of that air down to the surface due to the easterly wind, you get a high temperature of 85-90 degrees.  It is EXTREMELY rare to get 850mb temps above +16 in April.  In fact from 1992-2009, that’s 500+ days, there have only been 3 days that warm.  One that hit +17, and two that hit +18.  They were 86, 86, and 90 degree days here in Portland.  So will we break a record?

MarkWarm_PortlandRecords

The red columns are the records at PDX for the next 3 days, with my forecast numbers in yellow.  Wednesday is the day in 1998 when we hit 90 on the last day of the month, so no record coming that day.  I have a feeling we may break a record on Thursday though.

Enjoy the sunshine!

Chief Meteorologist Mark Nelsen


Snowy In Cascades; 80s Possible Next Week

April 23, 2014

10pm Wednesday…

Quite a dump of snow in the Cascades this afternoon/evening.

Sophie Hood Snow Totals

Looks like a foot or so has fallen so far above about 5,000′, with lighter amounts (just a few inches) down in the passes.  The snow level has zoomed up to around 6,000′ this evening in advance of the cold that moves through late tonight.  I expect another 3-5″ with the showers tomorrow, but no snow back down to the passes until tomorrow night.  This snow is overdue, because we’d typically see about 2′ of snow each April at Government Camp.  Check out the past 6 years up there…those were some cold/snowy Aprils around 2010!

MarkSnow_GovtCampApril

Here in the lowlands a very wet afternoon/evening as expected.  The rain was slow to arrive but now it’s here to stay through sunrise.

Thursday will be a showers and sunbreaks sort of day, same thing for Friday.  One more cold front moves into the Pacific Northwest Saturday and then a warm front drags across Sunday.  Then after ALL THAT, we see some warmer and drier weather.

By Tuesday and Wednesday a strong upper-level ridge will build right along the West Coast in advance of a cold digging upper-level trough in the east Pacific.  The GFS has finally come around to the sharper ridging the ECMWF has been showing.

MarkJetStream

We haven’t seen this pattern so far this spring with such highly amplified troughs and ridges.  It appears it won’t stick around long, but it will be a dramatic change with offshore flow and sunshine.  The ECMWF continues to be the warmest, showing 850mb temps +14 next Wednesday with easterly wind all the way to the beaches with a thermal trough.  That would give us a high temperature of 80-85 degrees in Portland.  I didn’t go that wild with temps (yet), but the main point is that we’ll likely see our warmest temps so far this spring for the last two days of April.  That’s AFTER 4 more days of wet weather.

Here are the 850mb ensemble charts from the 18z GFS and 12z ECMWF showing the sharp jump in upper-level temps the middle of next week:

tseries_850t_000-360_Portland

tseries_850t_000-384_Portland

 

Chief Meteorologist Mark Nelsen


6-7 Wet Days Ahead

April 21, 2014

11pm Monday…

The forecast for the next week is pretty clear; wet with cooler than average temperatures for late April.  This has been well-advertised on models and in forecasts, so I got my lawn mowed, burned some debris, and planted a few things that could use a week-long soaking.  Hope you all got anything taken care of that needs to be done outside too!

A chilly upper-level trough is about to move inland this evening.  It’s quite a pocket of chilly air; snow levels should dip down to around 3,000′ by sunrise.  Not a whole lot of moisture left at that time for big Cascade snowfall, but for the first time this month we should solidly white pass highways right at daybreak.

Then we’re into the showers/sunbreaks routine tomorrow as the strong April sunshine heats the ground, contributing to weak instability in the atmosphere.  With such a chilly air mass it’s possible you could see brief hail or thunder at your house if you live inland between the Coast Range and Cascades.

Wednesday and Thursday look WET!  Take a look at our RPM rain accumulation graphic:

MarkRain_RPM_NEXT24HOURS

Several surges of rain move through along with gusty southerly wind; looks more like early March than late April.  But we’ve been a bit above average so far this month temperature-wise so now it’s time to be a bit cooler (thus an “average”).

What about Cascade snow?  Quite a bit up around 5,000′, not too much below:

MarkHeadlines_SpringBreak

The milder than average temps the first part of April have accelerated the normal spring melt below about 5,000′ in the Cascades.  Note the snow water equivalent at 4,800′ Santiam Pass (Hogg Pass SNOTEL):

hogg

The solid blue line is this snow season’s SWE, the light blue is average.  You can see the plummeting values the first half of this month.

Up at the lower elevations of Timberline Ski Area at 5400′ the story is a bit better:

hood

With all the snow coming the next week at that elevation we’ll probably see the highest values of the season coming up, a “second peak”.  Interesting that at that site the average does linger at the maximum for a little over a month, then there is a quick fall-off as temperatures warm rapidly in late May.

Enjoy the rain…

There is some hope on the horizon.  Models give us at least some brief ridging about a week from now (NEXT Tuesday/Wednesday).  Take a look at the 850mb chart from the 00z GFS showing temperatures at the 5,000′ elevation returning to normal or a bit above after next Monday.

tseries_850t_000-384_Portland

You can see how the very warm 00z GFS operational run is quite an outlier.  I doubt we’ll be seeing a +17 deg C. temperature on the last day of April.  That would be a high temperature well into the 80s.  But it appears it will be warmer and drier right after our 7 Day forecast ends.  The 12z ECMWF was very warm as well and warmer than most of its ensemble members.  Here is the operational run showing high temps up around 80 at the same time:

KPDX_2014042112_dx_240

 

Chief Meteorologist Mark Nelsen

 


Easter Weekend: Wet, then Warm/Dry

April 18, 2014

11pm Friday…

Here’s our latest forecast for Easter Weekend:

Easter2012_2Day

quite a change from Saturday to Sunday.   I think Sunday afternoon will be one of those real nice spring afternoons…good enough for a BBQ!

Southerly flow pushes lots of high/mid clouds over us Monday with a shower possible just about anytime.

By Monday night, a chilly upper-level trough is approaching, increasing shower activity.  This leads us into a pretty long spell of cool and showery weather.  A 2nd cold trough settles in late next week and into the last weekend of the month.

Take a look at the 12z ECMWF and 00z GFS ensemble charts, you can see the below average temps through the next 7+ days beyond Tuesday.  Also notice very good agreement through that period too.

tseries_850t_000-384_Portland (1) tseries_850t_000-360_Portland

Better get your lawn mowed either Sunday or Monday!

 Chief Meteorologist Mark Nelsen