NNE Feb 24-25 Secondary Cyclogenesis and Upslope Obs

[dendrite]

The 12z models really hammer NNE with snowfall this evening through tomorrow morning as we get some secondary cyclogenesis occuring near LI and into far SNE. There shoud be a zone of sleet where WAA from the mid-level lows tracking to our NW advects in some >0C wetbulbs in the H75-H8 layer toward SW ME and S NH before thicknesses crash SE. Vim Toot could see over 10" of snow up in Aroostookland.

The 12z GFS, Ukie, RGEM, and the high res NMM are marginally mostly to all snow for the Lakes Region of NH while the NAM and SREFs are more of a mixed bag. Maybe some higher elevation west of here could get a period of mixed ZR/IP while the Merrimack Valley is more of a R/IP mix before everyone ends as a period of SN. Looks like similar issues toward dryslot, but it looks close there. This could bust either way.

The Greens, Whites, and ME mtns should get bombed and the upslope machine should continue for awhile for the Greens and Whites.

It's up to 34.6F here, but the dew is only 24F so we should still wetbulb down to near 0C at the sfc once the heavy precip makes its way in here.

[Baroclinic Zone]

I just took a look at the 12z GFS text soundings ror IZG. Solid warning criteria event for the Lakes Region of ME and points N. If this secondary can really bomb out early enough it will limit warming. It amazes me how these events (SWFE) seem to pan out relatively the same way.

[weatherMA]

Wow is it going to be close between getting 6+ and nothing.

[dendrite]

The 12z Euro looks warm aloft to start, but it ends as some +SN in C NH. N N/ME get hit hard 00-06z.

[Baroclinic Zone]

GGEM looks pretty solid as well. Simlar to the GFS.

[dendrite]

0.50"+ in 6hrs for IZG.

[weatherMA]

GYX is surprisingly bullish in S NH where it seems likely they get little to nothing.

[Baroclinic Zone]

0.50"+ in 6hrs for IZG.

Wow, thump. Messenger should go to Bretton Woods

[dendrite]

Wow, thump. Messenger should go to Bretton Woods

The Ukie has 0.75" in that 6hr period from PWM to IZG. Obviously not all of that near the coast is snow. At least it will be interesting tonight even if it only ends up a couple of inches here.

[Baroclinic Zone]

The Ukie has 0.75" in that 6hr period from PWM to IZG. Obviously not all of that near the coast is snow. At least it will be interesting tonight even if it only ends up a couple of inches here.

That just has that classic WAA thump. Agree, that it will be fun to watch pan out.

[CoastalWx]

I wouldn't be shocked if someone in downeast Maine had TSSN.

[Snow Bow]

GYX is surprisingly bullish in S NH where it seems likely they get little to nothing.

Yeah, there's a advisory for 4-6 in Rockingham county but zone says 2-4. The graphical forecast shows 3.6 for CON. Looks like we're gonna be in that lucky screw zone unless GYX is correct. They probably have the early release control run for the Euro already.

CON reporting -SN but nothing falling here. 35.4*

[dryslot]

Brian or Bob, I had an obs thread i started yesterday that you can merge or get rid of, I am riding the fence here as far as snowfall goes a subtle shift either direction could be good or bad...

http://www.americanwx.com/bb/index.php/topic/32871-february-24th-observation-thread/

[N. OF PIKE]

here's a question....since models don't seem to have a good handle on confluence even 24 hours inside regarding how it effects QPF/ and where meso features set up....(but start to get it around 8-12 hours out ..at least last nite) ....is there still much confluence effecting the evolution and track of this secondary cyclogenesis ) if at all.

i mean is there enough existing confluence to potentially push the WAA snows further south ...and in which case should we key in on the MESO Models again this PM and see where they shift to get insight? and i'm talking about how this may effect different areas in maine and Nh primarily (poss N orh hills)

[OKpowdah]

That just has that classic WAA thump. Agree, that it will be fun to watch pan out.

More than just a WAA thump. Impressive dynamics at play with the upper level trough too

[CoastalWx]

I definitely would want to be at a place like Sunday River and ne towards Tootsville.

[wxeyeNH]

32.4F/24 here. Been close to this all day. Bit of snow/sleet earlier just a slight dusting on the ground. Very interesting period this evening, like looking forward to a good sports game and not know how exactly its going to play out.

[Tropopause_Fold]

nice stretch of weather coming for you folks starting tonight...and going into the next week or so.

[ctsnowstorm628]

nice stretch of weather coming for you folks starting tonight...and going into the next week or so.

NNE looks good for this one. Next week has some potential as of last night...no where really to discuss it, but how is the 3/1 looking on the 12z runs? no comp to go over data...

[Snow Bow]

Starting to get some drizzle falling, temp up to about 38 now. Was down to 27.5 last night.

[N. OF PIKE]

here's a question....since models don't seem to have a good handle on confluence even 24 hours inside regarding how it effects QPF/ and where meso features set up....(but start to get it around 8-12 hours out ..at least last nite) ....is there still much confluence effecting the evolution and track of this secondary cyclogenesis ) if at all.

i mean is there enough existing confluence to potentially push the WAA snows further south ...and in which case should we key in on the MESO Models again this PM and see where they shift to get insight? and i'm talking about how this may effect different areas in maine and Nh primarily (poss N orh hills)

not trying to be a pest...just to learn ...anyone have info regarding this...out to lunch ,etc

i'm loggin off in like 10 mins and was wondering if confluence was a factor for CNE/NNE with the evolution of this secondary cyclogenesis ..esp considering how modeling doesn't seem to handle confluence accurately and meso's catch on eventually .

[N. OF PIKE]

euro weenie maps give dave and socks accumulating snow starting around 5-6 pm (4-7 pm .5 inch and then 7-10 pm 1-2 inches)

[J.Spin]

I just took a walk outside here on campus at UVM to grab some lunch, and the snow is certainly coming down out there. Flakes aren’t huge, probably topping out around 5 mm in diameter, but I’d say visibility is a mile or less as a quick guess (BTV was reporting 1.25 miles visibility as of 1:32 P.M.). Snow is accumulating on most non-paved surfaces.

[CoastalWx]

How is messenger skiing tomorrow with gusts to 70 on the mtn tops? Definitely going to be lift issues.

[HoarfrostHubb]

euro weenie maps give dave and socks accumulating snow starting around 5-6 pm (4-7 pm .5 inch and then 7-10 pm 1-2 inches)

Maybe freezing rain?

[N. OF PIKE]

How is messenger skiing tomorrow with gusts to 70 on the mtn tops? Definitely going to be lift issues.

bretton woods has fewer lift holds then adjacent mountains.

most will be on wind hold if forecast winds verify

[N. OF PIKE]

Maybe freezing rain?

dave you ever look at the weatherunderground euro maps.....go ahead take a peek

go to weatherunderground then click under maps and radar (go to models euro/ snowfall) etc

it's snow ...thus why box has you in 1-2 for this evening on there map

[weatherMA]

Yeah I bet Dave/Socks see 1-2" while I end as non accumulating 10 minute period of snow like you would see in a spring storm.

[mahk_webstah]

hello from north of NNE. light snow beginning in downtown montreal....juicy radar incoming. rooting hard to come home to 6+ on the ground.

[HoarfrostHubb]

dave you ever look at the weatherunderground euro maps.....go ahead take a peek

go to weatherunderground then click under maps and radar (go to models euro/ snowfall) etc

it's snow ...thus why box has you in 1-2 for this evening on there map

Oh, I have grown to love using wunderground for the Euro maps (esp the weenie snowfall feature)

I just am not going to believe it until I see it...lol

Seriously, I am thinking it might be a bit warm aloft. Not sure how to do/read a sounding, or where to even do it for.

I did look at the map more for the 3/1 threat, but noticed what it was showing here. Surface temps have been below freezing all day, but it has been drizzling. Maybe lift would help