December 2024 - Best look to an early December pattern in many a year!

[dendrite]

6.8° min here. CON 3°. 1P1 -4°

Saw Gunstock was mid 20s while it was low single digits at the base. 

Mins thru 12z. 

[Damage In Tolland]

53 minutes ago, CoastalWx said:

19 here and still dropping. A week of mild weather begins today. 

Should be cold by Thursday 

[dendrite]

For comparison purposes 

MOS from the other day 

[kdxken]

26 minutes ago, alex said:

-7 here in radiational cooling land. a bit frustrating to see the rain in the forecast with so many people visiting, but personally I’m really thankful - my sister was here for a week and it was just picture perfect Hallmark movie snow all week. We leave today for Yellowstone, excited about that! It’s a magical place in the winter. 

Magical place period.

[CoastalWx]

37 minutes ago, alex said:

-7 here in radiational cooling land. a bit frustrating to see the rain in the forecast with so many people visiting, but personally I’m really thankful - my sister was here for a week and it was just picture perfect Hallmark movie snow all week. We leave today for Yellowstone, excited about that! It’s a magical place in the winter. 

You live in the Yellowstone of the east.

[WxWatcher007]

12 days with teens or lower for lows here. December of yore at least in the temps department. December ‘23 had 2 and Dec ‘22 had 7.

[dendrite]

20 minutes ago, WxWatcher007 said:

12 days with teens or lower for lows here. December of yore at least in the temps department. December ‘23 had 2 and Dec ‘22 had 7.

More like December of norm lol

22 and 23 were exceptionally bad

[dendrite]

Just ran the numbers for BDL

1961-1990 the mean was 12 Dec days of mins < 20° (range 4 days to 29 days)

1991-2020 mean is 9 Dec days (range 0 days to 19 days)

[dendrite]

 Currently 19° at IJD and 32.2° for DIT. 

[Damage In Tolland]

4 minutes ago, dendrite said:

 Currently 19° at IJD and 32.2° for DIT. 

I think my sensor is sun affected with low sun angle hitting just right . I noticed same thing yesterday at this time and then it dropped all day after . I want to see if it drops back over the next hour or so 

[dryslot]

It was -1°F this morning, First below 0 temp this season.

[CoastalWx]

Just now, Damage In Tolland said:

I think my sensor is sun affected with low sun angle hitting just right . I noticed same thing yesterday at this time and then it dropped all day after . I want to see if it drops back over the next hour or so 

I get a little sun contamination too in the morning.

[dendrite]

ORH is 32°

You’re just above the inversion

[Damage In Tolland]

3 minutes ago, dendrite said:

ORH is 32°

You’re just above the inversion

Now it’s 31.6. I bet it drops a bit more. It only happens in the very low sun angle time of year 

[dendrite]

2 minutes ago, Damage In Tolland said:

Now it’s 31.6. I bet it drops a bit more. It only happens in the very low sun angle time of year 

I forget…do you have a fan? 

A half degree isn’t enough to convince me. The temp can wax and wane during the day too…especially with lighter mixing and being on the edge of the inversion. The inversions tend to slosh back and forth while gradually lowering during the morning with the mechanical mixing. 

[WxWatcher007]

48 minutes ago, dendrite said:

More like December of norm lol

22 and 23 were exceptionally bad

‘23 was unbelievably horrific lol

33 minutes ago, dendrite said:

Just ran the numbers for BDL

1961-1990 the mean was 12 Dec days of mins < 20° (range 4 days to 29 days)

1991-2020 mean is 9 Dec days (range 0 days to 19 days)

That’s awesome, thanks. Where can you calculate/pull this data from again? Can it also calculate average return times for things like 6”/12”/18” snow events?

[Damage In Tolland]

Just now, dendrite said:

I forget…do you have a fan? 

A half degree isn’t enough to convince me. The temp can wax and wane during the day too…especially with lighter mixing and being on the edge of the inversion. The inversions tend to slosh back and forth while gradually lowering during the morning with the mechanical mixing. 

No fan . Now back to 32.1. But yesterday it was showing 31.1 at 9:30 and all afternoon was in upper 20’s. Who knows 

[HoarfrostHubb]

KFIT taking off   27 at last hourly after getting down to 12

[WxWatcher007]

22.9 here. Could be icy here in the valley tomorrow. We do that well. Probably the only thing in winter. 

[dendrite]

15 minutes ago, WxWatcher007 said:

‘23 was unbelievably horrific lol

That’s awesome, thanks. Where can you calculate/pull this data from again? Can it also calculate average return times for things like 6”/12”/18” snow events?

I just used the NOWdata tab on the nws climo page. 
 

Monthly summarized data > min temps > number of days

[Damage In Tolland]

14 minutes ago, dendrite said:

I just used the NOWdata tab on the nws climo page. 
 

Monthly summarized data > min temps > number of days

Now it’s 29.3 . I’m convinced it ls that low sun angle hitting it just right this time of year. Imma turn it so it faces the other way 

[ORH_wxman]

1 hour ago, dendrite said:

Just ran the numbers for BDL

1961-1990 the mean was 12 Dec days of mins < 20° (range 4 days to 29 days)

1991-2020 mean is 9 Dec days (range 0 days to 19 days)

I just looped the entire month of Dec 1989 on reanalysis and it's amazing. The first time the 850 0C line makes it north of MA is 12/31/89 the entire month. Most of the month is spent double digit negatives at 850mb.

[Damage In Tolland]

9 minutes ago, Damage In Tolland said:

Now it’s 29.3 . I’m convinced it ls that low sun angle hitting it just right this time of year. Imma turn it so it faces the other way 

And now down to 27.8

[dendrite]

11 minutes ago, Damage In Tolland said:

And now down to 27.8

Maybe you’re right, but it could still be a wavering inversion. Would need to compare the temp in an aspirated shield. I’m still surprised sunlight would sneak under the gills in mid morning. 

[das]

2 hours ago, dendrite said:

ORH is 32°.  You’re just above the inversion

Here in Charlotte, just south of BTV, the inversion has been pretty cool.  The high yesterday and Christmas day was 21ºF with a low of 3ºF and 7ºF, respectively with freezing fog each evening and the development of hoar frost.  The inversion was only at around 900' and each time the DGZ would dip down below the inversion or the inversion would waver up, perfectly formed dendrites would start falling.  Here's a couple of pics my daughter took with a crappy cell phone:

I spent those two days up in Old Quebec City driving up on the 25th and back yesterday and took some pics of the inversion and freezing fog on my way back to VT yesterday evening. The temp alternated between 3ºF and -9ºF at sunset depending on the elevation of the St. Lawrence lowlands just to the north of the VT hills with those elevation differences only being ~20-30'.  The hoar frost was fer realz where the fog was heaviest:

...and the fog pics at sunset were awesome:

Sitting at 22ºF right now here in Charlotte with the deck lifted maybe 100' off of the ground.  I am at 238'.

[kdxken]

Pickaroon comes in handy when digging out firewood.

[tamarack]

-7 this morning, month's coldest.  Last 5 days averaged -3.  Without Christmas Eve it's -6 but the 6" of fluff that day was the best.

[Lava Rock]

31 minutes ago, tamarack said:

-7 this morning, month's coldest.  Last 5 days averaged -3.  Without Christmas Eve it's -6 but the 6" of fluff that day was the best.

i didn't radiate much at all on our hill. 19.9f

[codfishsnowman]

6 hours ago, ORH_wxman said:

I just looped the entire month of Dec 1989 on reanalysis and it's amazing. The first time the 850 0C line makes it north of MA is 12/31/89 the entire month. Most of the month is spent double digit negatives at 850mb.

That November had some frigid weather too. I remember upper teens under at least partial sunshine and gusty NW to 30 mph. While the Thanksgiving snowstorm was meh the few inches that did fall blew and drifted all over the place under mostly cloudy skies and temps falling below 20F

[dendrite]

6 hours ago, ORH_wxman said:

I just looped the entire month of Dec 1989 on reanalysis and it's amazing. The first time the 850 0C line makes it north of MA is 12/31/89 the entire month. Most of the month is spent double digit negatives at 850mb.

And then Jan 90 we struggled to get the 0C line south of MA. lol