September 2016 Observations and Model Discussion for the Pacific Northwest

[Geos]

The first month of meteorological autumn is almost upon us. 

 

CFS showing near normal to slightly above normal in the region.

 

 

Little low on precip - west.

 

[Front Ranger]

Looks like the first 1/3 of the month could be the coolest in a long time.

[Jesse]

Looks like the first 1/3 of the month could be the coolest in a long time.

CFSvC-3PO would beg to differ.

[wx_statman]

Looks like the first 1/3 of the month could be the coolest in a long time.

 

Last year PDX averaged 5.9F below normal through the first 7 days of September. It will be tough to beat that. 

[Front Ranger]

Last year PDX averaged 5.9F below normal through the first 7 days of September. It will be tough to beat that.

That's only like 23% of the month.

[wx_statman]

That's only like 23% of the month.

 

Good point. 

[snow_wizard]

The CPC dropped their September forecast from a high chance of above normal to equal chance on today's update.

[snow_wizard]

Last year PDX averaged 5.9F below normal through the first 7 days of September. It will be tough to beat that. 

 

It's actually possible.  The general pattern is capable of doing it, but it will come down to the details.

[snow_wizard]

Today's 12z GFS got me to thinking 1972 just a little bit.  It would be pretty exciting if it verified.

[ShawniganLake]

Today's 12z GFS got me to thinking 1972 just a little bit. It would be pretty exciting if it verified.

Wasn't 72 heading into a strong Nino?

[snow_wizard]

Wasn't 72 heading into a strong Nino?

 

It was.  That was one of the strangest El Nino seasons on record.

[wx_statman]

It was.  That was one of the strangest El Nino seasons on record.

 

The thing is though, from an observed temperature standpoint at the surface that winter had a pretty typical El Nino signature. At least on a macro level. The cold was done by January 12th and the rest of the winter was typical Nino blues. 

[wx_statman]

For a strange El Nino winter, I like 1987-88. Consistently chilly through January and into early February, which is something you don't normally see in a moderate or strong Nino. 

 

Of the 11 El Nino winters since 1950 that averaged at least a 1.0 ONI between Oct-Dec, 1987-88 is the only one where the coldest weather of the season occurred in the late January/early February period (35/22 at PDX on 2/2). In a typical Nino that calendar stretch is reliably mild. 

[BLI snowman]

For a strange El Nino winter, I like 1987-88. Consistently chilly through January and into early February, which is something you don't normally see in a moderate or strong Nino.

 

Of the 11 El Nino winters since 1950 that averaged at least a 1.0 ONI between Oct-Dec, 1987-88 is the only one where the coldest weather of the season occurred in the late January/early February period (35/22 at PDX on 2/2). In a typical Nino that calendar stretch is reliably mild.

February-March 1988 were very ridgy though, and the coldest stretch overall was in the late December/beginning of January period, both of which are typical Niño traits.

 

I think 1968-69 and 1896-97 take the prize as "weirdest" El Niños.

[Bryant]

Although all the action is just south of us, that line of heavy precip is holding together nicely. Lightning will light up the room here and there. Started raining hard enough on the way home that I pulled off to take a slower and safer route with the wife and baby in the car, took a video along the way. 

 

https://goo.gl/photos/2nMkvdf1iREsKcm67

[ShawniganLake]

Although all the action is just south of us, that line of heavy precip is holding together nicely. Lightning will light up the room here and there. Started raining hard enough on the way home that I pulled off to take a slower and safer route with the wife and baby in the car, took a video along the way. 

 

https://goo.gl/photos/2nMkvdf1iREsKcm67

Impressive storm cell. 

[Phil]

Although all the action is just south of us, that line of heavy precip is holding together nicely. Lightning will light up the room here and there. Started raining hard enough on the way home that I pulled off to take a slower and safer route with the wife and baby in the car, took a video along the way.

 

https://goo.gl/photos/2nMkvdf1iREsKcm67

Awesome video, man!

[Bryant]

Impressive storm cell. 

 

Scared the out of my wife, lol

[Bryant]

Awesome video, man!

 

Thanks, you would have seen it sooner if you would check your messenger

[wx_statman]

February-March 1988 were very ridgy though, and the coldest stretch overall was in the late December/beginning of January period, both of which are typical Niño traits.

 

I think 1968-69 and 1896-97 take the prize as "weirdest" El Niños.

 

1968-69 was a borderline weak/moderate Nino though. 1987-88 was solidly moderate, bordering on strong at least if you use the ONI index.

 

I like 1896-97 in this example. No freezes at downtown Portland between December 2nd and January 10th, then an Arctic blast in late January. Exactly the opposite of what you would expect in a Nino winter. 

[wx_statman]

1.58" in one hour @ Sedro Woolley

 

http://www.wrh.noaa.gov/mesowest/getobext.php?sid=SWYW1&table=1&banner=off

[BLI snowman]

1968-69 was a borderline weak/moderate Nino though. 1987-88 was solidly moderate, bordering on strong at least if you use the ONI index.

 

I like 1896-97 in this example. No freezes at downtown Portland between December 2nd and January 10th, then an Arctic blast in late January. Exactly the opposite of what you would expect in a Nino winter. 

 

Also the coldest March on record for Portland in 1897. Very Nina like. March is generally a blowtorch in a stronger El Nino.

[James Jones]

1968-69 was a borderline weak/moderate Nino though. 1987-88 was solidly moderate, bordering on strong at least if you use the ONI index.

 

I like 1896-97 in this example. No freezes at downtown Portland between December 2nd and January 10th, then an Arctic blast in late January. Exactly the opposite of what you would expect in a Nino winter. 

I think March 1897 being that cold was the most bizarre thing about that Nino. You can almost always count on February and March being warm in a Nino, but that March was the coldest on record for Portland. An average high of 45.7 is just nuts.

[Bryant]

1.58" in one hour @ Sedro Woolley

 

http://www.wrh.noaa.gov/mesowest/getobext.php?sid=SWYW1&table=1&banner=off

 

Incredible. I couldn't believe how strong the cell was while driving through it

[Bham_Guy]

1.58" in one hour @ Sedro Woolley

 

http://www.wrh.noaa.gov/mesowest/getobext.php?sid=SWYW1&table=1&banner=off

 

I'm wondering if that's one of the higher hourly rainfall totals ever recorded in the lowlands of Western WA.

[wx_statman]

Also the coldest March on record for Portland in 1897. Very Nina like. March is generally a blowtorch in a stronger El Nino.

 

That's a good point about March. 

 

That cold season shared a number of similarities with 1955-56, a strong Nina. Both had major cold spells in November, late January, and March. That's definitely more of a Nina progression. 

[wx_statman]

Incredible. I couldn't believe how strong the cell was while driving through it

 

That was some seriously heavy rain in that video. I've only seen it rain that hard a couple times in Portland. 

[Geos]

Although all the action is just south of us, that line of heavy precip is holding together nicely. Lightning will light up the room here and there. Started raining hard enough on the way home that I pulled off to take a slower and safer route with the wife and baby in the car, took a video along the way. 

 

https://goo.gl/photos/2nMkvdf1iREsKcm67

 

That is impressive. 

Still going too. Although it seems to be moving more towards the mountains now.

[wx_statman]

I'm wondering if that's one of the higher hourly rainfall totals ever recorded in the lowlands of Western WA.

 

I'm not sure, but yeah it has to be up there. The PDX record for one hour is only 1.03". 

[wx_statman]

1.58" in one hour @ Sedro Woolley

 

http://www.wrh.noaa.gov/mesowest/getobext.php?sid=SWYW1&table=1&banner=off

 

This station just updated. 2.55" in two hours.

[Bryant]

This station just updated. 2.55" in two hours.

 

Pretty amazed the cell held together as long as it did.

[Bryant]

I'm not sure, but yeah it has to be up there. The PDX record for one hour is only 1.03". 

 

Any idea where those records are kept? Would love to take a look for the Whatcom / Skagit County area 

[Phil]

Thanks, you would have seen it sooner if you would check your messenger

Lol, sorry. For some reason I haven't gotten notifications from Facebook messenger since I updated to IOS 9.3.5. Have to check it manually..meh.

[wx_statman]

Any idea where those records are kept? Would love to take a look for the Whatcom / Skagit County area 

 

As far as I know, the short term rainfall records are only kept at first order stations. Portland, Seattle, etc. 

 

For example the Portland NWS has rainfall records for PDX on their website. 

[snow_wizard]

The ECMWF is very chilly for the entire run.  Really nippy shortwave diving toward us at the end.

[Bryant]

As far as I know, the short term rainfall records are only kept at first order stations. Portland, Seattle, etc. 

 

For example the Portland NWS has rainfall records for PDX on their website.

 

Thanks for the info, was worth a try

[Phil]

The ECMWF is very chilly for the entire run. Really nippy shortwave diving toward us at the end.

Not a fan of that +NAM developing during week2. Will make it easier for the PV aloft to strengthen uninhibited, though I guess one should expect a strong early-winter PV in a +QBO anyway.

[Geos]

Not a fan of that +NAM developing during week2. Will make it easier for the PV aloft to strengthen uninhibited, though I guess one should expect a strong early-winter PV in a +QBO anyway.

 

Isn't September a bit early for the PV to get going?

[Phil]

Isn't September a bit early for the PV to get going?

September is when it gets going..the dominoes start falling in earnest from mid/late September through mid/late October.

[wx_statman]

Thanks for the info, was worth a try

 

I wish COOP stations kept more records like that. Would definitely give us a better idea how historic tonight's rainfall was.