April 2020 Weather discussion for the PNW

[TT-SEA]

You can see where it’s going, though, with the negatively tilted ridge axis off CA and building -NAM (haven’t seen that in awhile during late April/May).

 

Definitely looks like a different pattern than what we have seen recently.  

[Timmy Supercell]

Definitely looks like a different pattern than what we have seen recently.  

 

Happy 502,777th post

[Dan the Weatherman]

Happy 502,777th post

 I know he posts a lot on here, but 502,777 posts sounds far out even for a very frequent poster. Is this number really correct??

[TT-SEA]

 I know he posts a lot on here, but 502,777 posts sounds far out even for a very frequent poster. Is this number really correct??

 

 

No... Fred bumped it up from 50,000 to 500,000 in January as a joke.

[ShawniganLake]

Warm out there this afternoon. Probably the warmest day of spring so far.

[TT-SEA]

Warm out there this afternoon. Probably the warmest day of spring so far.

 

 

Cooler here... only 64.    

 

Tomorrow we should get in on that warmer air up there.

[Dan the Weatherman]

No... Fred bumped it up from 50,000 to 500,000 in January as a joke.

I did the math regarding since you joined back in 2014, that you would have had to post 220 times per day on average to reach this number. I know you are a very frequent poster, but I somehow didn't believe that 502,779 number and I also remember seeing your total post count much lower just a few months ago.

 

Thanks for clarifying!

[TigerWoodsLibido]

Clouds starting to break up. Maybe some stars tonight?

[Frontal Snowsquall]

12Z EPS is a little less zonal in that period...

 

Looks like a return to a ridgy pattern towards the end of the month. Hopefully we can get a few days of onshore flow before then.

[Frontal Snowsquall]

You can see where it’s going, though, with the negatively tilted ridge axis off CA and building -NAM (haven’t seen that in awhile during late April/May).

When was the last time we saw that in late April/May?

[Deweydog]

Fired up the sprinklers today!!!

[Jesse]

[MossMan]

Nice day!

[Phil]

When was the last time we saw that in late April/May?

I think 2016, coming off the super niño.

[TT-SEA]

I think 2016, coming off the super niño.

 

 

Yeah... the first half of April has been stormy and wet for the last 3 years.

 

This year is the complete opposite.   

[ShawniganLake]

Cooler here... only 64.

 

Tomorrow we should get in on that warmer air up there.

69 here this afternoon. We topped out at 65 last week

[Frontal Snowsquall]

I think 2016, coming off the super niño.

That was a nice summer here. Not too hot overall compared to recent ones we have had. I wouldn't mind some sort of repeat.

 

[Jesse]

I think 2016, coming off the super niño.

That was one of our warmest Aprils on record and also a top 5 warm May, fwiw.

[Jesse]

Down to 55 here currently after a high of 66 today. Looks like some showers fired up over the Cascades/Gorge this afternoon.

[Jesse]

New 7-day from Mark finally shows a rainy day at the end. Also wouldn’t surprise me to see the Sunday-Tuesday period which are currently forecast in the mid-upper 60s all end up 70+.

 

[El_Nina]

Down to 55 here currently after a high of 66 today. Looks like some showers fired up over the Cascades/Gorge this afternoon.

Was hoping some of those could have made it into the valley. They were close.

Looks like a fire weather watch is up for the area.

https://forecast.weather.gov/wwamap/wwatxtget.php?cwa=pqr&wwa=fire%20weather%20watch

[Jesse]

Was hoping some of those could have made it into the valley. They were close.

Looks like a fire weather watch is up for the area.https://forecast.weather.gov/wwamap/wwatxtget.php?cwa=pqr&wwa=fire%20weather%20watch

So early...

[ShawniganLake]

So early...

https://www.google.ca/amp/s/vancouversun.com/news/uncontrolled-slash-fire-burning-fast-prompting-evacuations-near-squamish-rcmp/wcm/783c8b96-64f5-411c-bdba-31110d45ad89/amp/

[El_Nina]

https://www.google.ca/amp/s/vancouversun.com/news/uncontrolled-slash-fire-burning-fast-prompting-evacuations-near-squamish-rcmp/wcm/783c8b96-64f5-411c-bdba-31110d45ad89/amp/

But that's north of here.

[ShawniganLake]

But that's north of here.

Yea. Pretty early for the BC Coast.

[TT-SEA]

12Z EPS is a little less zonal in that period...

 

 

 

00Z EPS for comparison...

 

[Kayla]

90% of Oregon is now in a drought with over 60% of the state in at least a moderate drought. Not good.

 

[TT-SEA]

90% of Oregon is now in a drought with over 60% of the state in at least a moderate drought. Not good.

 

 

 

Oregon (and northern CA) has been caught in the middle... between wetter conditions to the north and farther south.

 

Much different story for western WA and southern CA.

[Kayla]

Oregon (and northern CA) has been caught in the middle... between wetter conditions to the north and farther south.

 

Much different story for western WA and southern CA.

 

Yeah...though the Washington Cascades are also in a drought as well.

[TT-SEA]

Yeah...though the Washington Cascades are also in a drought as well.

 

 

Snow pack is at or above 100% for most of the WA Cascades.

 

And its been wet this year so far...

 

 

 

Maybe its picking up on the drier than normal conditions east of the Cascades... but the mountain snow pack is much more important over there in terms of available water.

 

 

A much different story in western Oregon...

 

[Kayla]

Snow pack is at or above 100% for most of the WA Cascades.

 

And its been wet this year so far...

 

Maybe its picking up on the drier than normal conditions east of the Cascades... but the mountain snow pack is much more important over there in terms of available water.

 

 

A much different story in western Oregon...

 

 

Yeah I was speaking more about the east slopes. Moisture really got hung up on the west side this year. 

[Frontal Snowsquall]

90% of Oregon is now in a drought with over 60% of the state in at least a moderate drought. Not good.

 

One of the reasons I hope we get some rain this spring. With how the coronavirus attacks the lungs, the last thing we need is to make it even more harder on people by breathing in wildfire smoke. Coronavirus + Wildfire smoke is a bad combination.

[Front Ranger]

That was one of our warmest Aprils on record and also a top 5 warm May, fwiw.

 

Yeah, April 2016 was legit blowtorch. Warmest on record for OLM.

[TT-SEA]

Yeah I was speaking more about the east slopes. Moisture really got hung up on the west side this year.

Definitely.

 

A huge chunk of WA and OR have been drier than normal this year so far... but western WA and the WA Cascades are the notable exception.

 

Oregon is not in a very good place heading into the warm season. But a cooler and wetter summer can effectively mitigate the fire season despite a dry start as we saw last year.

[Frontal Snowsquall]

Snow pack is at or above 100% for most of the WA Cascades.

 

And its been wet this year so far...

 

 

 

Maybe its picking up on the drier than normal conditions east of the Cascades... but the mountain snow pack is much more important over there in terms of available water.

 

 

A much different story in western Oregon...

 

Crazy how wet it's been up there for you guys in the Cascade foothills and mountains. Also been drier than normal in Eastern Washington, quite the anomalies.

[Phil]

Looking at Michael Ventrice’s hurricane season forecast, it looks like he’s also seeing low frequency tropical convective forcing increasingly centered over the Indian Ocean with time (mentions the descending easterly shear favoring a reduction in off-equator convection, which is generally true as well). Also, dateline/WPAC subsidence would typically correspond to uplift in the IO without the +IOD focusing uplift in the W-IO (can be a high wavenumber regime with a weak low pass) so that makes sense.

 

This would, based on history (even very recent history) suggest offshore Aleutian/GOA Ridging (-PNA) would be favored to dominate the warm, along with drier than average conditions, especially over the SW US and inland. But PWAT anomalies would be lower than average with such a pattern.

 

[Jesse]

Hit a low of 38 this morning. Lots of sub-40 lows this month. All but a handful of mornings.

 

Glad to see a wetter pattern slowly marching into focus on the models. Hope to see momentum keep up with today’s runs.

[Jesse]

Looking at Michael Ventrice’s hurricane season forecast, it looks like he’s also seeing forcing increasingly centered over the Indian Ocean (mentions the descending easterly shear favoring a reduction in off-equator convection, which is generally true as well).

This would, based on history (even very recent history) suggest offshore Aleutian/GOA Ridging (-PNA) would be favored to dominate the warm, along with drier than average conditions, especially over the SW US and inland. But PWAT anomalies would be lower than average with such a pattern.

You must have missed my reply to your post yesterday. The main region of the west in which a -PNA regime would affect summertime moisture transport is the monsoon influenced areas of the SW.

 

Summers with below average heights in our area west of the Cascades tend to be wetter even if it is a drier pattern for most of the west.

[Frontal Snowsquall]

Definitely.

 

A huge chunk of WA and OR have been drier than normal this year so far... but western WA and the WA Cascades are the notable exception.

 

Oregon is not in a very good place heading into the warm season. But a cooler and wetter summer can effectively mitigate the fire season despite a dry start as we saw last year.

Yeah, I'm a little concerned down here but we still got 2 solid months before summer really gets going. Lots of time to get some rain down here.

[Phil]

You must have missed my reply to your post yesterday. The main region of the west in which a -PNA regime would affect summertime moisture transport is the moonsoon influenced areas of the SW.

I guess I did.

 

The departures from normal in terms of precipitation are certainly much larger down there when reanalyzing boundary state analogs, and I’m very concerned about CA and the SW US this summer. More so than I’ve been in awhile. But even in the PNW, precipitable water anomalies and overall precipitation w/ respect to climo seems to decline as summer wears on, especially inland, even with a “cool” signal clearly present. Certainly, there’s nothing close to the level of moisture that was showing up in the analogs last year at this time.

 

It’s less “dry” in June on the West Side for some reason, but the signal flips around in July except up in BC and at the immediate coast, then it’s all dry in August, but it’s still a significantly cooler signal vs the one in WPAC forcing/+PMM years. There aren’t many IO/EHEM dominated summers, I suppose, so maybe it’s not a familiar pattern to memory? I’ll post all of this when I’m finished.