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January 2021


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20 minutes ago, ORH_wxman said:

Total Totals in the low 60s tomorrow....that is really impressive. I definitely wouldn't be shocked to see someone get lucky down south with a couple inches. Max DGZ is around 800mb too, so that is going to help too.

There's actually a lot of WINDEX parameters satisfied in this...big time TTs, huge LI spike, LL moisture, good PVA, etc.

What was the WINDEX check list that was floating around out there in the earlier web days... 

Man, I regret not saving that.  I google it now and it's hard to find.  

The only thing I remember about it was the vertical temperature/lapsing and the LIs ... You're talking about tornado stuff there - lol...  

Kidding, but my memory of that check list from the mid 1990s was: 

R1 RH > 50%

LI jumps up +9

And a T1 to T3 lapse rate of > -9  

   but those were FOUS numbers.  No one uses those grids anymore so... that may also be why the old checklist as I recall is harder to find nowadays.  Which incidentally the FOUS does show these criteria met ( abv )

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4 minutes ago, Typhoon Tip said:

What was the WINDEX check list that was floating around out there in the earlier web days... 

Man, I regret not saving that.  I google it now and it's hard to find.  

The only thing I remember about it was the vertical temperature/lapsing and the LIs ... You're talking about tornado stuff there - lol...  

Kidding, but my memory of that check list from the mid 1990s was: 

R1 RH > 50%

LI jumps up +9

And a T1 to T3 lapse rate of > -9  

   but those were FOUS numbers.  No one uses those grids anymore so... that may also be why the old checklist as I recall is harder to find nowadays.  Which incidentally the FOUS does show these criteria met ( abv )

Oh its the original Lundstedt paper. Just search his name and "wintertime instability index" and I'm sure you'll find it.

But from what I remember, you want

1. T1 RH above 50% (preferably above 75%)

2. T1-T5 layer lapse rate of more than 10C (more than 14C was huge signal for squalls provided other parameters were good)

3. LI spike of more than 8 in a 12h period

Some other "factors" to consider, but they tie into the above....big PVA (usually associated with the LI spike) and TTs over 50 (associated with very steep lase rates)

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9 minutes ago, USCAPEWEATHERAF said:

Hey Tip, I am sorry, your hood is not in line for anything weather wise the next seven days, but that does not mean the southerners in the region won't get impacted.  The coastal storm is close enough that I am going to monitor the latest and Worcester is getting snow showers right now.

I don't think anyone is remiss that they will miss this impact.

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12 minutes ago, 78Blizzard said:

As has been said before, it's all about equilibrium.  I'd be curious what the other side of the globe (Russia, Siberia, northern China) is showing for BN thermals during our torch.  Less than two weeks ago, Beijing had its lowest temperature in over 50 years.

I understand the interest ...but, Siberia just spent what ... 7 years > normal 90% of the time.  

This may not even typify their whole winter  but just a several week stint within - I don't know though.  

Not only is the ballast of GW being registered in the nocturnal temperature behaviors ... but, the models aver that the frequency of disruptive events should increase along the with the change.  I think running along at some acclimated 7 year above normal stretch, then having that rudely offset by a Medusa cold wave fits that.  

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7 minutes ago, Typhoon Tip said:

What was the WINDEX check list that was floating around out there in the earlier web days... 

Man, I regret not saving that.  I google it now and it's hard to find.  

The only thing I remember about it was the vertical temperature/lapsing and the LIs ... You're talking about tornado stuff there - lol...  

Kidding, but my memory of that check list from the mid 1990s was: 

R1 RH > 50%

LI jumps up +9

And a T1 to T3 lapse rate of > -9  

   but those were FOUS numbers.  No one uses those grids anymore so... that may also be why the old checklist as I recall is harder to find nowadays.  Which incidentally the FOUS does show these criteria met ( abv )

 

Screenshot_20210119-154658_Drive.jpg

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6 minutes ago, ORH_wxman said:

Oh its the original Lundstedt paper. Just search his name and "wintertime instability index" and I'm sure you'll find it.

But from what I remember, you want

1. T1 RH above 50% (preferably above 75%)

2. T1-T5 layer lapse rate of more than 10C (more than 14C was huge signal for squalls provided other parameters were good)

3. LI spike of more than 8 in a 12h period

Some other "factors" to consider, but they tie into the above....big PVA (usually associated with the LI spike) and TTs over 50 (associated with very steep lase rates)

Hey ...I wasn't far off - not bad LOL

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2 hours ago, ORH_wxman said:

I feel the exact opposite actually....the temp gradient between NNE and SNE has been very low....hence the +9 to +10 anomalies up north and the +6 to +7 anomalies in ORH and BOS. We've lacked good baroclinicity most of the month.

 

Thought he last 2 or 3 days that hasn't been the case as there was a frontal boundary that cooled off NNE while we were still torching a bit down here.

There's not even any ice around here. I just set stakes in the ground and the frost is about an inch hit or miss depending upon sunlight. Maybe it's because the average high up there has been below freezing and certainly above freezing down here.  I dunno. I'm not sure the Lowell area has seen an inch of snow since Christmas whereas I've nickel and dimed my way to to 15" up north. Today's just another example where the high up there was 27 but 40 down here. Usually it's only about 6 or 7 degrees. Maybe because it's been so much warmer than average at both places.

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1 minute ago, ORH_wxman said:

Someone's gonna grab at least that much I think....wouldn't surprise me if a few lucky peeps got 2-3".

Will what do you think about this shortwave tilting negative quicker on the latest model trends?  I mean every piece of guidance has trended towards a quicker tilt negative like before NYC and a stronger surface low that develops now west of the benchmark?  However the models I think are too far south with the system!

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36 minutes ago, Typhoon Tip said:

I understand the interest ...but, Siberia just spent what ... 7 years > normal 90% of the time.  

This may not even typify their whole winter  but just a several week stint within - I don't know though.  

Not only is the ballast of GW being registered in the nocturnal temperature behaviors ... but, the models aver that the frequency of disruptive events should increase along the with the change.  I think running along at some acclimated 7 year above normal stretch, then having that rudely offset by a Medusa cold wave fits that.  

I was only talking about this period that you referenced ORH being +7F, just out of curiosity, and to indicate that weatherwise, not climatewise, things usually even out around the globe (northern hemisphere anyway).

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