May obs/discussion thread - Welcome to Severe Season!!

[weatherwiz]

3 minutes ago, Supernovice said:

Interesting paper on the impacts of the Australian Wildfires in 2019-2020.  Interesting how the smoke doesn't get into the stratosphere but still impacts sensible weather. good read.

TLDR- Contributed to the 3 yr long (unprecedented) La Nina.

https://www.nature.com/articles/d41586-023-01588-8

Can't read the article, but did they really call the 3-year La Nina unprecedented? They're certainly uncommon but not sure if I would categorize it as unprecedented. There have been several dating back to the late 1800's and multiple within the ONI dataset going back to 1950.

[ma blizzard]

23 minutes ago, weatherwiz said:

I was checking that and it wasn't showing anything. I checked the Vertically Integrated Smoke and 1000/6000 AGL products. 

I think there might be an issue with the smoke originating out of the domain of the HRRR so it isn't picking it up? At least I remember reading something like that on twitter last week. Pretty sure I saw a RAP product showing the smoke though. 

[weatherwiz]

2 minutes ago, ma blizzard said:

I think there might be an issue with the smoke originating out of the domain of the HRRR so it isn't picking it up? At least I remember reading something like that on twitter last week. Pretty sure I saw a RAP product showing the smoke though. 

Ahhh that's a very good point. Went to the RAP and there is the smoke!

[Supernovice]

4 minutes ago, weatherwiz said:

Can't read the article, but did they really call the 3-year La Nina unprecedented? They're certainly uncommon but not sure if I would categorize it as unprecedented. There have been several dating back to the late 1800's and multiple within the ONI dataset going back to 1950.

money quote:

"First, is that typically La Niña follows El Niño, but this is an example of a La Niña event that had no preceding El Niño. That’s not completely impossible, but unlikely. The second thing is, we had this La Niña event that lasted for three years that didn’t follow an El Niño. That is unprecedented. Previous long-lasting La Niñas have always happened after a strong El Niño.”

[Ginx snewx]

1 hour ago, CoastalWx said:

If this smoke keeps up, toss those lows. 

Doesn't effect radiation though.

[Typhoon Tip]

Not that anyone asked but my hunch is that the smoke will alleviate when the -EPO circulation mode tapers off... 

The region/source/origin of the smoke has been in a semi persistent dry/warm anomaly due to the W/NW flow over continental terrain of NW Canada and/or ridging, which is a down-slope trajectory and only augments the circumstance ...

If we trust the GEFS/GEPs ...that regime changes between D7 and 10. 

In fact, it may also herald in summery layout S of 50 N across much of continent when that happens, too. 

[Damage In Tolland]

6 minutes ago, Ginx snewx said:

Doesn't effect radiation though.

Hilltops and winds do 

[Damage In Tolland]

40 minutes ago, weatherwiz said:

I was checking that and it wasn't showing anything. I checked the Vertically Integrated Smoke and 1000/6000 AGL products. 

RAP is the smoke model to use 

[Damage In Tolland]

1 hour ago, CoastalWx said:

If this smoke keeps up, toss those lows. 

Smoke em if you got em?

[weatherwiz]

2 minutes ago, Damage In Tolland said:

RAP is the smoke model to use 

For some reason I always forget about the RAP. I think I keep confusing it with the RUC and thing it's no longer a thing...which is an odd thinking because the SPC mesoanalysis utilizes the RAP. 

[Typhoon Tip]

Higher res vis loops over the continental perspective shows that the cold front punching S across W Ontario is sharply evacuating the smoke behind.  This air mass coming in isn't sourced over NW Canada...   It's a "continental folding" pattern. 

Get a load of the standing wave cloud pattern over the terrain, boning us for sun even more than the smoke alone this hour.   Overall, we're in an anomalous hemisphere right now, so ... in principle, hosting anomalous behavior ... if in subtle ways.  That's doing that over 2,500' ridge line like the Sierra Nevada

[Spanks45]

1 hour ago, CoastalWx said:

If this smoke keeps up, toss those lows. 

I hope so....no rain for 10 days, clear skies, calm winds on my sandy backyard...desert radiating for ftl

[wxeyeNH]

Hey guys, checking in...

Alberta smoke is very thick this morning.  Clearly visible on the satellite pictures.  It is interesting you are discussing the smoke affect with the frost/freeze potential coming up.  I have been wondering if the fropa would bring Eastern Canadian air down from Quebec and shove the smoke to our south for a couple of days?  Looks like that would happen. What level do you most of the smoke is? 850mb?  Looking outside from my view I can easily see 30 miles.

I found this smoke website  https://firesmoke.ca/forecasts/current/

[CoastalWx]

1 hour ago, dendrite said:

In cases where it’s thinner…doesn’t it affect shortwave rad more than longwave?

Certainly helps keep temps down during the day. I assume it has some affect on night temps?

[Typhoon Tip]

It's interesting ...  I almost wonder if the smoke is actually augmenting these terrain triggered cloud plumes over the lower Monad/range, by providing an over-abundance of condensation nuclei

... We are busting temperatures pretty badly as of the hour.  It may release all at once in an hour and then we abruptly clear. Though we'll have the smoke filtration still in place.

I've read that SAL in the tropics creates an overly proficient condensation nuclei - just wondering if that microphysics are similar in principle.

[Typhoon Tip]

Loop this ...  https://weather.cod.edu/satrad/

...gives the distinct impression that we'll end up N of the smoke axis as this trough amplitude and round-house cold punch us.

[Typhoon Tip]

My personal feel on that frost/freeze issue is that smoke will mean nothing to the success/failure in that realization ... because it is evac'ed away from the region - been discussing the issue. 

This air mass will be sufficiently cold enough for frost (freeze N)... the main limiting factor would be wind and success in decoupling enough to go calm. 

[weatherwiz]

1 minute ago, Typhoon Tip said:

My personal feel on that frost/freeze issue is that smoke will mean nothing to the success/failure in that realization ... because it is evac'ed away from the region - been discussing the issue. 

This air mass will be sufficiently cold enough for frost (freeze N)... the main limiting factor would be wind and success in decoupling enough to go calm. 

The core of the sfc high is really just off to our west, but it would appear winds should go calm. Obviously the question is do we decouple...or do some locals decouple and others don't? 

It's going to be pretty gusty during the day tomorrow but winds should diminish rather quickly moving towards the evening (at least per guidance). Seems like they valley/typical radiation spots should decouple. Hills will certainly be warmer given the above sfc inversion. 

[powderfreak]

BTV AFD sounds like near record cold on Wed night.  

It`s entirely possible we could observe some daily record lows with values in the teens to mid 20s in the Dacks and Northeast Kingdom and to the upper 20s to lower 30s in the broad valleys. Several sites will be within 5 degrees of records, with Montpelier and Saranac Lake currently forecast to break the record at time of writing.

[dendrite]

1 hour ago, CoastalWx said:

Certainly helps keep temps down during the day. I assume it has some affect on night temps?

Oh that was my point. Less shortwave heating during the day, but not much longwave effect at night. 

[dendrite]

Definitely a golden glow out there today. 

[tamarack]

2 hours ago, weatherwiz said:

Can't read the article, but did they really call the 3-year La Nina unprecedented? They're certainly uncommon but not sure if I would categorize it as unprecedented. There have been several dating back to the late 1800's and multiple within the ONI dataset going back to 1950.

Unless I've mis-copied the ENS data presented here by red taggers, we had 3 ninas 1998-99 thru 2000-01 just since I moved to the Maine foothills.  The period 2010-11 thru 2014-15 began with 2 ninas then 3 nadas, 5 years with no ninos.  Farther back, the period 1970-71 thru 1975-76 included 5 ninas with only the strong nino of 1972-73 breaking up the 6-year run.

It`s entirely possible we could observe some daily record lows with values in the teens to mid 20s in the Dacks and Northeast Kingdom and to the upper 20s to lower 30s in the broad valleys.

Just when I thought our apple blossoms were safe.     Even GYX whispered about possible teens in northern valleys within their CWA.
Latest we've gone below 25 was 5/14/20, a very cold spring with phenology running more than 10 days behind.  We had 25 on 5/20/02, but that followed 4 weeks of 5° BN temps with 6.2" snow 4/26-29 and another 0.3" on 5/13, again a late-blooming spring.  This year is 5-7 days ahead of average so we're vulnerable to late killer frost.

[wxeyeNH]

Hum,  The 12Z GFS comes in colder again.  29F in my area of Plymouth NH for 2 hours.  925mb is colder too, down to -1F.  

Smoke is very thick right now, very dim sun so we will start with a lower launching pad this evening.  It will be interesting to see how this plays out.  All our apple trees are in full bloom.  Argghhh

[SJonesWX]

4 hours ago, weatherwiz said:

Pretty soon all of North America will be covered in smoke. This is what the dinosaurs must have encountered before they went extinct. 

you would think that they would have been smart enough to run away from all the green dots, and especially the yellow, red, and orange ones.

[Damage In Tolland]

We have received word that someone who is very anti install and pro open windows , has completed all installations today . WTTTE

[Typhoon Tip]

You know ... the way this trough swings through so quickly, and the whole air mass rolls right on out 24 to 30 hours later ...it really reminds me of a tepid version of that ordeal back in early February that brought the ridic cold that lasted all of 18 hours... 

I was just looking at the 12z GGEM and it returns heights to 576+ by Thursday evening... No memory of where it was 24 hours earlier... and certainly, unaware considering where we are now. 

Very similar

[powderfreak]

16 minutes ago, Damage In Tolland said:

We have received word that someone who is very anti install and pro open windows , has completed all installations today . WTTE

Today’s my first day on the internet… but what does WTTE mean?  

[Brian5671]

Windows open here-great temp of 77 here

[Damage In Tolland]

8 minutes ago, Typhoon Tip said:

You know ... the way this trough swings through so quickly, and the whole air mass rolls right on out 24 to 30 hours later ...it really reminds me of a tepid version of that ordeal back in early February that brought the ridic cold that lasted all of 18 hours... 

I was just looking at the 12z GGEM and it returns heights to 576+ by Thursday evening... No memory of where it was 24 hours earlier... and certainly, unaware considering where we are now. 

Very similar

Tomorrow’s really no big deal at all. One day near 60 with low dews and some wind… some forests burn to the ground and that’s it. Not sure why it’s getting so much hype . We get one every Mayorch 

[Typhoon Tip]

1 hour ago, Damage In Tolland said:

Tomorrow’s really no big deal at all. One day near 60 with low dews and some wind… some forests burn to the ground and that’s it. Not sure why it’s getting so much hype . We get one every Mayorch 

Mm  I get the sentiment but this appears to be a little more amped than that.  There's record cold in the region during the night... It may fail, but it's in the discussion, and that should be fairly qualified as more than a 'no big deal'

But the occurrence of cold in May - I'll definitely entertain the notion that exceeding 1 SD cold, as a part of the CC signal, or at minimum has been a recurrent theme in our springs now going back 15 to 20 years regardless, with marked increase in frequency over the previous 100 years