September 2019 Weather Discussion for the PNW

[Geos]

Down to 44 here now. Was in Bothell at about 6pm and the rain started pouring in huge drops mixed with small hail. Really snarled up traffic more than it was already. 

[Deweydog]

First time I’ve worn underwear since February.

[MossMan]

.03” over the last hour. 5.27” on the month.

 

45 degrees.

[GHweatherChris]

Pretty cold out there. Had to close the office window for the first time since May.

Wife closed our bedroom windows on me, I am pissed, it is 68 in the house, balmy.

[umadbro]

47 degrees now which is the coldest it's been since May. Teething 8 month year old makes it balmy though. In and out of bed every 20-30 minutes. That'll keep Tim warm.

[TigerWoodsLibido]

Still 51F here. Let’s see if we make it down into the 40s.

[joelgombiner]

There is a pretty strong correlation between low solar activity and high latitude blocking. This gives you an idea (solar min winters back to the 1950s), but keep in mind that there is big variance in solar mins, as well as overall cycles and activity. But basically, more blocking means better chance of major cold at the mid latitudes.

 

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What is the physical mechanism linking solar activity to earth atmospheric processes?

[MossMan]

Had a low of 40. Currently 44 and cloudy.

[MR.SNOWMIZER]

This is crazy for this time of year. When I left my cabin the wind was blowing from north about 25 with falling temps.

[MossMan]

This is crazy for this time of year. When I left my cabin the wind was blowing from north about 25 with falling temps.

Wow! You didn’t have to go very many months to see snow again there!

[Chewbacca Defense]

We hit 41 at 11pm before rebounding to 46 overnight.  Dropped back down to 43 around sunrise.  Sun is trying to burn through the clouds now. 

 

My boss has been driving back from the east coast and has been racing to get through Montana before the storm hit today.  They drove 16 hours and made it to Cour d' Alene last night.  Looks like its trying to switch to snow in Spokane.

[ShawniganLake]

Looks like some outflow is starting to work into the lower Fraser valley

[TT-SEA]

Pretty morning... and a little snow on top of Mt Si

 

[Jesse]

Some decent snowfall at Government Camp this morning. One of the earliest snows I can ever remember seeing up there, and close to one of their earliest snowfalls on record. Earliest ever was September 23, 1984, at least according to Mark’s blog.

 

 

Luckily we managed to finish up data collection on Adams yesterday before things got too dicey. Snow was falling down to 4,000 and lower by the time we left in the late afternoon.

[Cloud]

Eerily similar pattern to last February. Was just reviewing the data from a station near my house and you could tell where it began as well.

 

From 3pm-8pm the temps dropped from 63 to 50. More specifically, the temps went from 57 to 50, from 6pm-8pm. Was outside a little after 7 and it was a chilly wind. By 1am it was 46 and it stayed there consistently throughout the night.

 

Feels like a shock to the system.

[Blizzard777]

Low of 46*@12:59am and held there thought the night

Currently 47* and cloudy

24 hour rainfall .11

3.27 inch for the month

Wind calm

 

Pretty cool Mount Si got snow!

4,000 foot or a smidge lower seems to be the magic number

[GHweatherChris]

Low of 46*@12:59am and held there thought the night

Currently 47* and cloudy

24 hour rainfall .11

3.27 inch for the month

Wind calm

 

Pretty cool Mount Si got snow!

4,000 foot or a smidge lower seems to be the magic number

Snow level was forecast to be 3500-4000 feet so not surprising.

[TT-SEA]

Not much going on at Snoqualmie Pass this morning...

 

[TT-SEA]

But there is a coating of snow at mid-mountain on Alpental... I believe this is above 4,000 feet.     The top of Alpental is at 5,420 feet.

 

[Jesse]

Snow level was forecast to be 3500-4000 feet so not surprising.

It is surprising to see it that low this early, though.

[SilverFallsAndrew]

My buddy lives at Crooked River Ranch in Central Oregon about 2750'. He is seeing sticking snow this morning!

 

[GHweatherChris]

Chilly morning.

[TigerWoodsLibido]

Got down to 45 at EUG and 42 in Springfield and we haven’t even switched to a continental profile yet, still 6 MPH s wind at the last report.

[SilverFallsAndrew]

Looks like only 4 times has snow accumulated at Gov't Camp in September since 1951, before today. Last time was 0.2" on 9/30/2009, so this is the earliest since 1984. All-time daily record is 3", so with this heavy band, they may have a shot at getting close to that. 

[SilverFallsAndrew]

Got down to 45 at EUG and 42 in Springfield and we haven’t even switched to a continental profile yet, still 6 MPH s wind at the last report.

Had this been January, EUG would have been the big winner with the arctic front. Way more precip down there. Most other valley locations would have just had a dusting. 

[BLI snowman]

Had this been January, EUG would have been the big winner with the arctic front. Way more precip down there. Most other valley locations would have just had a dusting. 

 

South wind there still, that's 34 degree snow.

[SilverFallsAndrew]

Currently 44 with light rain. All-time September min/max at Silver Falls is 48, we might get close today or tomorrow. 

[Front Ranger]

Looking more and more like a pretty widespread snow for eastern WA tonight into tomorrow.

[SilverFallsAndrew]

South wind there still, that's 34 degree snow.

 

D**n! Well we would have gotten about 4" up here and it would be snowing still and about 27 degrees right now...

[BLI snowman]

Looks like only 4 times has snow accumulated at Gov't Camp in September since 1951, before today. Last time was 0.2" on 9/30/2009, so this is the earliest since 1984. All-time daily record is 3", so with this heavy band, they may have a shot at getting close to that. 

 

I remember them getting a decent amount on 9/28/2007. Looks like they recorded 0.60" of precip that day with a 35/32 spread.

[SilverFallsAndrew]

Looks like at least 1-2" on the ground at Government Camp!

[SilverFallsAndrew]

I remember them getting a decent amount on 9/28/2007. Looks like they recorded 0.60" of precip that day with a 35/32 spread.

 

Snow data is so spotty . 

[Jesse]

I remember them getting a decent amount on 9/28/2007. Looks like they recorded 0.60" of precip that day with a 35/32 spread.

The late September 2007 setup came to mind with this discussion. I remember driving up the mountain that day specifically to see the early snows (which I may also do today). But it was fairly slushy at pass level then, if I recall. Had to go up the Timberline road a little to get into the sticky stuff.

[SilverFallsAndrew]

Another deep trough showing up on the GFS.

 

[Jesse]

Another deep trough showing up on the GFS.

 

Mild nights pattern.

[SilverFallsAndrew]

Mild nights pattern.

 

Yeah, this sucks. This morning we only got down to 42, which is actually average for the date (First night of the month that was not above average!), guess we'll have to do with a 20-25 degree below average high!

[Jesse]

Yeah, this sucks. This morning we only got down to 42, which is actually average for the date (First night of the month that was not above average!), guess we'll have to do with a 20-25 degree below average high!

A midnight low seems pretty out of the question too. Sorry Charlie.

[Phil]

Looks like only 4 times has snow accumulated at Gov't Camp in September since 1951, before today. Last time was 0.2" on 9/30/2009, so this is the earliest since 1984. All-time daily record is 3", so with this heavy band, they may have a shot at getting close to that.

D**n. Impressive stuff.

 

Very intriguing high/low frequency exchanges ongoing right now re: wavetrains/seasonality given the background state present. Didn’t really see it evolving this way. Looks more like a 19th century pattern..has registered as neutral/+PNA just like many of those frigid PNW years did at the end of the LIA, thanks to the orientation of the wavestations relative to the EOF for the modern PNA index, but in reality it’s just a different pattern throwing off the calculation.

[SilverFallsAndrew]

A midnight low seems pretty out of the question too. Sorry Charlie.

 

More mild nights

 

[SilverFallsAndrew]

Temp back down to 43 with moderate rain. Hard to believe it is still September and the average high for the date here is 71.