April 2024 Weather in the PNW

[Front Ranger]

11 minutes ago, SilverFallsAndrew said:

Get some lotion on those hands, amigo!

[TT-SEA]

A little warmer out here away from the water and protected from the north wind. 

[T-Town]

39 minutes ago, MossMan said:

HCS is ruining my deck sunning session.

High clouds have moved out here and HCS catastrophe is averted. Currently 62 degrees on the sunning deck. 

[Deweydog]

37 minutes ago, Front Ranger said:

Get some lotion on those hands, amigo!

It does this whenever its told. 

[Anti Marine Layer]

52 minutes ago, SilverFallsAndrew said:

What happened to the warm 70 degree day?

[Mercurial]

Gorgeous day wow.  Did the 6 mile roundtrip hike to Beaver Lake, which is now completely melted and ice free.

 

[Phishy Wx]

71 and slaying

went and sat at the brewery and had some beers outside

[TigerWoodsLibido]

54F with some heavy rain.

[SilverFallsAndrew]

Heavy rain from Willamette Pass to Dexter.

[MossMan]

Looks a little bumpy down south. 
HCS has luckily ceased up here! Back to the blue skies! 

Edited April 14 by MossMan

[Cascadia_Wx]

9 hours ago, Frontal Snowsquall said:

I didn’t think they got out of the 60s but yeah they made it. We got more daytime peak heating now with the later sunsets. First 8pm sunset of the year coming on Wednesday.

Looks like only 68 at PDX today. Big underachievement!!

[Meatyorologist]

4 hours ago, Cascadia_Wx said:

We’ve probably had a dozen or more iterations of this exact same discussion over the years and August keeps getting hotter.

Jinx’s and superstition don’t do a lot to circumvent a rapidly warming region/planet, sadly

Not if I pour ice water on KPDX's thermometer every hour for the next five months.

[Meatyorologist]

3 hours ago, SilverFallsAndrew said:

#neverstopchasing

[Cold Snap]

4 hours ago, TT-SEA said:

Landscape starting to take on the summer look.   Just drove from North Bend to Bellevue and the trees are uniformly at about the same stage on that drive... about the same in NB as in Bellevue.

The trees look nowhere close to that in Duvall. Though they are leafed out a bit.

[TT-SEA]

Global warming has stopped!  Or maybe slowed down.  Either way today was huge win.

[TT-SEA]

5 minutes ago, Cold Snap said:

The trees look nowhere close to that in Duvall. Though they are leafed out a bit.

Interesting.    Maybe colder nights out there? 

This was 4 days ago in North Bend.  Quite a bit farther along now.  

[Cold Snap]

4 minutes ago, TT-SEA said:

Interesting.    Maybe colder nights out there? 

This was 4 days ago in North Bend.  Quite a bit farther along now.  

There have been a decent amount of nights in the 30s here recently. Probably something to do with that. Also in Downtown Duvall which is about 350 feet lower elevation than where I live seems like it’s a bit more leafed out.

[Deweydog]

1 hour ago, MossMan said:

Looks a little bumpy down south. 
HCS has luckily ceased up here! Back to the blue skies! 

Sprinkles verified here. Made it through the doubleheader but some folks FREAKED OUT when the drops dropped. MY PHONE SAID NO RAIN!!

[Meatyorologist]

Buddy and I went on a walk to enjoy the catastrophe today. Saw some cumulus shrouding Mt. Rainier, lots of high clouds, sunny, mild weather.

Him and I are both science nerds so we got to talking about adiabatic cooling and how it works... Neither of us really knew the exact answer, and none of the information we read online felt comprehensive or satisfying. After some shared thought my buddy tossed me a theory that I think makes the most sense. As he guessed, as a parcel rises, and the volume of that parcel increases, the fastest moving ("hottest") molecules in that parcel travel outwards towards the edge first, since they are faster. Those "hot" molecules, being the first of the parcel to make direct contact with the environent surrounding it, transfer their heat out via conduction. It's essentially a molecule sorting process, where the hottest molecules are most likely to conduct their thermal energy to the surroundings, since they are faster than the rest of the molecules, and fill in the expanding parcel first. As you can imagine, transferring heat out of the parcel via the warmest particales preferentially will cool off the parcel, and at a fixed, predictable rate, too.

Any seasoned mets want to pitch in? Are we onto something or shooting blanks? Don't know where else to ask. Maybe Reid Wolcott knows.

[Frontal Snowsquall]

3 hours ago, MossMan said:

HCS is ruining my deck sunning session.

A high cloud shocker down here as well! . Only made it to 68 at PDX but still a +7 high departure.

[T-Town]

Sunset pics. 

[Anti Marine Layer]

20 minutes ago, Frontal Snowsquall said:

A high cloud shocker down here as well! . Only made it to 68 at PDX but still a +7 high departure.

Something about the above post bothered Jesse.

[Frontal Snowsquall]

5 hours ago, Cascadia_Wx said:

God willing!

Unfortunately it looks like the moisture didn’t quite make it up north. We will have another chance on Monday and Tuesday but it looks like we might be too far south. It looks like PDX is in the donut hole at the moment.  

So far PDX is running 43% of normal precipitation about halfway through the month of April.

[Meatyorologist]

10 minutes ago, Frontal Snowsquall said:

Unfortunately it looks like the moisture didn’t quite make it up north. We will have another chance on Monday and Tuesday but it looks like we might be too far south. It looks like PDX is in the donut hole at the moment.  

So far PDX is running 43% of normal precipitation about halfway through the month of April.

Salem should be grateful.

[Meatyorologist]

Eugene got over half an inch of rain today. Solid.

[Mercurial]

Some of our trees have buds... no blooms or flowers, though.  Not even a dandylion.  Probably a couple more weeks to go.

[DareDuck]

.26” so far today with potentially a little more overnight. Love getting a soaking spring rain on the high desert. 

[Cascadia_Wx]

Ended up with a 66/46 day here. Nice day but definitely ended up with more cloudiness than expected. Always nice when things break in a good way for once.

The rain down south was good to see too. Hope we get a turn at it soon.

[TT-SEA]

00Z ECMWF looks much less troughy later in the run than it's 12Z run.    Nice when things trend the good way.   

Monday is solidly cloudy and chilly... Tuesday ends up quite sunny but still chilly.   Then looks like a pretty nice run of sunny, pleasant weather.  

[the_convergence_zone]

3 hours ago, Meatyorologist said:

Buddy and I went on a walk to enjoy the catastrophe today. Saw some cumulus shrouding Mt. Rainier, lots of high clouds, sunny, mild weather.

Him and I are both science nerds so we got to talking about adiabatic cooling and how it works... Neither of us really knew the exact answer, and none of the information we read online felt comprehensive or satisfying. After some shared thought my buddy tossed me a theory that I think makes the most sense. As he guessed, as a parcel rises, and the volume of that parcel increases, the fastest moving ("hottest") molecules in that parcel travel outwards towards the edge first, since they are faster. Those "hot" molecules, being the first of the parcel to make direct contact with the environent surrounding it, transfer their heat out via conduction. It's essentially a molecule sorting process, where the hottest molecules are most likely to conduct their thermal energy to the surroundings, since they are faster than the rest of the molecules, and fill in the expanding parcel first. As you can imagine, transferring heat out of the parcel via the warmest particales preferentially will cool off the parcel, and at a fixed, predictable rate, too.

Any seasoned mets want to pitch in? Are we onto something or shooting blanks? Don't know where else to ask. Maybe Reid Wolcott knows.

This is a great question. So, if you’re using parcel theory, then you’re assuming an adiabatic process when lifting the parcel. Which means no heat transferred between the parcel and the environment. So no conduction. What is actually assumed to be happening is that the molecules in the parcel are doing work on the molecules in the surrounding air — they are literally bumping into them and pushing them out of the way because the parcel is expanding as it rises. So that cools the temperature of the parcel because of the energy conversion (work being done). But no net heat loss to the environment! dq=0

Another assumption of parcel theory is homogeneity, so there are no faster or slower molecules; they are all the same. 
 

If you throw parcel theory out the window and think about the real world, then you would have some conduction, but air is a poor conductor…if you think about a double paned window in the winter. for instance, very little of the heat from your house is getting out through that window because of the air gap. The main failure mode of parcel theory in the atmosphere is mixing.

Anyway, hope that helps! 

[jcmcgaffey]

2 hours ago, Meatyorologist said:

Buddy and I went on a walk to enjoy the catastrophe today. Saw some cumulus shrouding Mt. Rainier, lots of high clouds, sunny, mild weather.

Him and I are both science nerds so we got to talking about adiabatic cooling and how it works... Neither of us really knew the exact answer, and none of the information we read online felt comprehensive or satisfying. After some shared thought my buddy tossed me a theory that I think makes the most sense. As he guessed, as a parcel rises, and the volume of that parcel increases, the fastest moving ("hottest") molecules in that parcel travel outwards towards the edge first, since they are faster. Those "hot" molecules, being the first of the parcel to make direct contact with the environent surrounding it, transfer their heat out via conduction. It's essentially a molecule sorting process, where the hottest molecules are most likely to conduct their thermal energy to the surroundings, since they are faster than the rest of the molecules, and fill in the expanding parcel first. As you can imagine, transferring heat out of the parcel via the warmest particales preferentially will cool off the parcel, and at a fixed, predictable rate, too.

Any seasoned mets want to pitch in? Are we onto something or shooting blanks? Don't know where else to ask. Maybe Reid Wolcott knows.

Adiabatic vs evaporative cooling is always a good debate in a mechanical engineer’s world in regards to most efficient cooling systems.  I’ll have to ask some folks at work next week and see what they think. 

[the_convergence_zone]

20 minutes ago, the_convergence_zone said:

This is a great question. So, if you’re using parcel theory, then you’re assuming an adiabatic process when lifting the parcel. Which means no heat transferred between the parcel and the environment. So no conduction. What is actually assumed to be happening is that the molecules in the parcel are doing work on the molecules in the surrounding air — they are literally bumping into them and pushing them out of the way because the parcel is expanding as it rises. So that cools the temperature of the parcel because of the energy conversion (work being done). But no net heat loss to the environment! dq=0

Another assumption of parcel theory is homogeneity, so there are no faster or slower molecules; they are all the same. 
 

If you throw parcel theory out the window and think about the real world, then you would have some conduction, but air is a poor conductor…if you think about a double paned window in the winter. for instance, very little of the heat from your house is getting out through that window because of the air gap. The main failure mode of parcel theory in the atmosphere is mixing.

Anyway, hope that helps! 

So I’m still thinking about this…we’re starting with a homogeneous parcel but once the bumping starts, the molecules on the edge of the parcel that bump into another molecule will slow down (i.e. cooled) so then you would sort-of be in the situation you describe where there are faster and slower ones. And in that case the faster ones would then be more likely to do the bumping as the parcel expands. 
 

But this just shows why parcel theory is mathematically convenient but not at all a reflection of what actually goes on in the real world. Because the second you let a real parcel go in the environment it would immediately start mixing with the surrounding air. 

[Deweydog]

3 hours ago, Meatyorologist said:

Buddy and I went on a walk to enjoy the catastrophe today. Saw some cumulus shrouding Mt. Rainier, lots of high clouds, sunny, mild weather.

Him and I are both science nerds so we got to talking about adiabatic cooling and how it works... Neither of us really knew the exact answer, and none of the information we read online felt comprehensive or satisfying. After some shared thought my buddy tossed me a theory that I think makes the most sense. As he guessed, as a parcel rises, and the volume of that parcel increases, the fastest moving ("hottest") molecules in that parcel travel outwards towards the edge first, since they are faster. Those "hot" molecules, being the first of the parcel to make direct contact with the environent surrounding it, transfer their heat out via conduction. It's essentially a molecule sorting process, where the hottest molecules are most likely to conduct their thermal energy to the surroundings, since they are faster than the rest of the molecules, and fill in the expanding parcel first. As you can imagine, transferring heat out of the parcel via the warmest particales preferentially will cool off the parcel, and at a fixed, predictable rate, too.

Any seasoned mets want to pitch in? Are we onto something or shooting blanks? Don't know where else to ask. Maybe Reid Wolcott knows.

I always thought the adiabatic process was all about friction, at least in the weather world. Usually upslope vs. downslope and the excitement/relaxing of the molecules. Of course it’s just armchair stuff, my actual science knowledge is purely wannabe status.

[TT-SEA]

Pretty strong troughy signal on the 00Z EPS towards the end of the run.  

[SilverFallsAndrew]

Well look at that. Someone posted a cold anomaly map. 

[SilverFallsAndrew]

Misty and foggy morning. Someone forgot to give us the torching memo. South of Portland was pretty nice yesterday but even nicer was all the rain in Central Oregon! 

[MossMan]

Had a low of 38. Currently 38. 

[MossMan]

6 minutes ago, SilverFallsAndrew said:

Well look at that. Someone posted a cold anomaly map. 

Yeah and I puked on it. 

[TT-SEA]

22 minutes ago, SilverFallsAndrew said:

Well look at that. Someone posted a cold anomaly map. 

I do that all the time... just looking for strong signals either way.    Take it as it comes Andrew.   We are only here for a short while.

[TT-SEA]

Live view this morning from a hotel in Bellevue... we had to use free points that were about to expire so did dinner and bowling night with the kids.   Heading to Charleston in a few days so stayed very local this time.  Unlike all you rich 1% people traveling all over the country on your own dime for a 4-minute eclipse... Charleston is an annual tag long business trip at no expense to us.