April 2017 Observations and Model Discussion for the Pacific Northwest

[BLI snowman]

So the summer of 93 got hot in the end?

 

July was drippy and cold and September was hot and bone dry. Not the ideal progression.

[Jesse]

Probably. Stopped raining, now it just needs to dry out so I can mow!

Hopefully your weekend can be saved.

[Jesse]

I'm actually a little excited about the dramatic warmup this week. The fact that it looks increasingly likely to be followed by a sharp crash makes it all the sweeter.

[BLI snowman]

The potential for a 55+ low on Thursday is troubling to say the least.

[Jesse]

The potential for a 55+ low on Thursday is troubling to say the least.

12z GFS hints at some warm core convection Thursday afternoon.

[seattleweatherguy]

12z GFS hints at some warm core convection Thursday afternoon.

Thunderstorms?

[epiceast]

The potential for a 55+ low on Thursday is troubling to say the least.

Open ALL windows!

[BLI snowman]

12z GFS hints at some warm core convection Thursday afternoon.

 

Comes down to timing of everything as usual, but looks likely to be our first shot of the year.

[Jesse]

Thunderstorms?

Would be nice.

[Jesse]

Comes down to timing of everything as usual, but looks likely to be our first shot of the year.

It certainly isn't uncommon to get something on the backside of these early season warm spikes. Especially when a ULL is in play offshore.

[BLI snowman]

It certainly isn't uncommon to get something on the backside of these early season warm spikes. Especially when a ULL is in play offshore.

 

Definitely.

 

May 1, 1998 was a good one.

[Jesse]

Hopefully the EURO is showing its cutoff bias in recent runs. I like how the GFS handles things better.

[Front Ranger]

Hopefully the EURO is showing its cutoff bias in recent runs. I like how the GFS handles things better.

It really lost the crash. Friday is looking quite warm on today's run. Would be a very warm first 10 days of May overall.

[Deweydog]

Thunderstorms?

Nope. We're cooking a rack of lamb.

[Jesse]

It really lost the crash. Friday is looking quite warm on today's run. Would be a very warm first 10 days of May overall.

At least California would benefit from some widespread late-season rainfall on this run.

[SilverFallsAndrew]

At least California would benefit from some widespread late-season rainfall on this run.

I think they have had to much rain.

 

We need it more.

[IbrChris]

Some well-deserved temps ~80 middle of next week for PDX...then back to regular spring programming. I'll be down in AZ where PHX is slated to be in the low 100s late next week. The following weekend may give way to some strong winds in the lower deserts which means potential for blowing dust or even a haboob.

[Front Ranger]

Tim is missing out on another lovely day in Seattle.

 

[Jesse]

I think they have had to much rain.

 

We need it more.

 

Welcome to the Forum Fantastic club!

 

Dewey and Tim will be over shortly with your free Trump® weather station and a used VHS copy of the 1996 Bill Paxton classic, "Twister".

[Jesse]

Some well-deserved temps ~80 middle of next week for PDX...then back to regular spring programming. I'll be down in AZ where PHX is slated to be in the low 100s late next week. The following weekend may give way to some strong winds in the lower deserts which means potential for blowing dust or even a haboob.

 

Actually, some runs are hinting that the warmth could stick around for awhile.

[SilverFallsAndrew]

Welcome to the Forum Fantastic club!

 

Dewey and Tim will be over shortly with your free Trump® weather station and a used VHS copy of the 1996 Bill Paxton classic, "Twister".

 

RIP Bill Paxton

[Front Ranger]

RIP Bill Paxton

 

SPOILER ALERT: He does survive "Twister". Some very close calls, though!

[TT-SEA]

Tim is missing out on another lovely day in Seattle.

 

Screenshot_1.png

 

Parents said its been dumping rain all day until about 20 minutes ago.    C-zone perfectly placed again.   Later this week my area will likely be one of the warmest in King County.

[TT-SEA]

82 and partly cloudy here... absolutely perfect day.   And the ocean water is so warm.

 

Could be the same temperature in my backyard on Thursday.   

[Phil]

Ain't gonna happen. This summer will not be a '93 redux.

Funny, I seem to recall you mocking my warm-up call a few weeks ago. How does that crow taste?

 

The pattern will be similar. Probably not as chilly verbatim, but still similar on the large scale.

[TT-SEA]

Funny, I seem to recall you mocking my warm-up call a few weeks ago. How does that crow taste?

 

The pattern will be similar. Probably not as chilly verbatim, but still similar on the large scale.

 

 

It was crazy wet (rain on many days) in the Seattle area in June and July of that year... very odd situation.   Also record-setting wet in the Midwest.

 

Do you think it will be so extremely wet as 1993?   Seems almost impossible to believe considering we are coming off record setting rain for the last 3 months.

[Phil]

It was crazy wet (rain on many days) in the Seattle area in June and July of that year... very odd situation. Also record-setting wet in the Midwest.

 

Do you think it will be so extremely wet as 1993? Seems almost impossible to believe considering we are coming off record setting rain for the last 3 months.

Do I think it'll be as wet as 1993? No.

 

Do I think the large scale pattern will be similar? Yes. The upper level jet is the strongest since 2011 this year, but 1993 had a much stronger one.

 

I could also see things flipping warmer for August/September this year depending on how ENSO evolves.

[Front Ranger]

Funny, I seem to recall you mocking my warm-up call a few weeks ago. How does that crow taste?

 

The pattern will be similar. Probably not as chilly verbatim, but still similar on the large scale.

 

Never happened. I said about a week ago that your call for a warm late April looked to be in jeopardy.

 

Was an accurate assessment.

[TT-SEA]

Do I think it'll be as wet as 1993? No.

 

Do I think the large scale pattern will be similar? Yes. The upper level jet is the strongest since 2011 this year, but 1993 had a much stronger one.

 

I could see things flipping warmer for August/September this year depending on how ENSO evolves.

Almost as wet would still suck. Even more so for the Midwest.

[Front Ranger]

The pattern will be similar. Probably not as chilly verbatim, but still similar on the large scale.

 

You already sure about that? I thought you mentioned before that we have to wait until May to get a good idea of the warm season pattern.

[Front Ranger]

BLI only managed to pick up .02". The drought continues there.

[Front Ranger]

It was crazy wet (rain on many days) in the Seattle area in June and July of that year... very odd situation.   Also record-setting wet in the Midwest.

 

Do you think it will be so extremely wet as 1993?   Seems almost impossible to believe considering we are coming off record setting rain for the last 3 months.

 

SEA didn't hit 80 in either June or July that year. Nuts.

[IbrChris]

On second thought I'd go warmer mid-week...now looks like 85-88 is possible.

Consider the last five runs of the Euro ensembles...highest 850 mb temp for next Wednesday May 3rd:

4/28 12z: 12.9c
4/29 00z: 13.2c
4/29 12z: 15.4c
4/30 00z: 16.4c
4/30 12z: 17.1c

Looking at recent climatology for May at SLE (00z 850 temp vs high temp):

23.0c....95 degrees on May 15, 2006
22.0c....99 degrees on May 16, 2008
20.8c....90 degrees on May 27, 2005
19.6c....91 degrees on May 26, 2005
18.8c....87 degrees on May 13, 2012

18.4c....92 degrees on May 17, 2008

18.2c....80 degrees on May 14, 2012
18.2c....87 degrees on May 28, 2009

18.0c....88 degrees on May 15, 2008
17.8c....89 degrees on May 30, 2009
16.8c....88 degrees on May 28, 2007
16.8c....84 degrees on May 15, 2006
16.6c....88 degrees on May 29, 2007

16.2c....85 degrees on May 18, 2008

16.0c....88 degrees on May 29, 2009

15.6c....84 degrees on May 31, 2009

Early May there was a nice warm spell in 2013:

16.4c....83 degrees on the 10th
15.2c....85 degrees on the 11th

15.2c....81 degrees on the 9th

14.4c....87 degrees on the 5th

14.4c....81 degrees on the 6th

Seems like mid to perhaps upper 80s is a possibility at 17c with 90 becoming possible around 18-19c.
 

[IbrChris]

Enjoy it because if Phil's hunch is correct this might be one of only a handful of 80s this year. In 1954 we only saw 10 days of 80+, 27 in 1955 and 1964, 28 in 1948 and 30 in 1953. The 1950s were rough in Portland if you liked warm summers.

More recently in 2010 we only managed 37 days. The POR average is 52 days of 80+ a year while the 1981-2010 normal is 56 days.

The high was 88 days in 2015...amazing summer that year. The 67 days in 2013, 77 in 2014, 88 in 2015 and 71 in 2016 are unrivaled in terms of consecutive summers with >10% more 80s than normal.

[VancouverIslandSouth]

BLI only managed to pick up .02". The drought continues there.

 

That's the real story this month, it hasn't been that abnormal in terms of rainfall (at least in many northern areas). Currently sunny and 60F here, here's to hoping for at least a normal May in terms of rainfall; maybe the pattern we saw in the second half of April shifts north.

[SilverFallsAndrew]

Enjoy it because if Phil's hunch is correct this might be one of only a handful of 80s this year. In 1954 we only saw 10 days of 80+, 27 in 1955 and 1964, 28 in 1948 and 30 in 1953. The 1950s were rough in Portland if you liked warm summers.

 

More recently in 2010 we only managed 37 days. The POR average is 52 days of 80+ a year while the 1981-2010 normal is 56 days.

 

The high was 88 days in 2015...amazing summer that year. The 67 days in 2013, 77 in 2014, 88 in 2015 and 71 in 2016 are unrivaled in terms of consecutive summers with >10% more 80s than normal.

 

Chris with a WxStatman caliber climate post. Love it!

[VancouverIslandSouth]

Looks like tomorrow's system might have a bit of kick to it after all, the 18z NAM brings it ashore before it breaks apart .

 

http://www.tropicaltidbits.com/analysis/models/nam3km/2017043018/nam3km_mslp_pcpn_frzn_nwus_22.png

[Phil]

Never happened. I said about a week ago that your call for a warm late April looked to be in jeopardy.

 

Was an accurate assessment.

Was it really in jeopardy, though? Or, was the clown range GFS just wrong?

[Phil]

Almost as wet would still suck. Even more so for the Midwest.

I don't think I'd even take it that far. I don't know how your microclimates work, so I'm not making any deginitive calls on precipitation. The large scale pattern favors increased Pacific moisture transport overall, but if I make any statements beyond that, I'd be talking out of my arse.

 

I do think the large scale pattern will be similar to 1993, but shifted poleward a bit due to the somewhat more expanded Hadley Cells versus the early 1990s (though they have retracted notably since 2013-16).

[Phil]

You already sure about that? I thought you mentioned before that we have to wait until May to get a good idea of the warm season pattern.

May starts in a few hours. In reference to the second half of summer, yes, that depends on the ENSO and IO/Indo evolution, which is still up the air.

 

However, it's now clear that a stronger Niño is off the table, and given the progression of the tropical forcings and QBO/SAM, I am now able to make some extrapolations into early July. Beyond that, I'm not sure, but I'm leaning warmer for August and September. Almost the opposite progression relative to last year, when the warm anomalies peaked early before things trended cooler overall through the summer and fall.