vortex95

What's this rear weenie bonus convectivey-NORLUN type stuff at the end??? 12z had it as well. Nothing would surprise me given how odd this season is so far w/ local snow maxes!

That would be pushing it WSW. Too much uncertainty w/ low ratios and mild sfc temps.

Some areas have already done well, Already had a 6" event on Cape Cod, and parts of CT and central/western MA has done reasonably well also. Now, it just the area bounded roughly by BOS-LWM-FIT-PVD-GHG that has been "holed" so far. CoastalWx is in this "hole!"

It's like you can't have it both ways. More intensity but warmer BL, or less intensity but colder BL? Weenie sweet spot somewhere between ORH and TAN? CoastalWx I know is hopeful! LOL.

I am not impressed overall w/ this event, despite the storm further NW. MOS shows sfc temps 34-38 F for most of the event across much of CT, all of RI, eastern MA, and Cape Cod. And precip intensity is not nuts (best 6 hr LEQ amount on the HRRR I see is .50" over the outer Cape), so despite the cold 850 and 925, the BL remains a big problem. There is zero high pressure to our N. In fact, it is one big trough from Labrador to the Great Lakes. This is rare for a coastal storm, and key for ptype in this event. So the low-level cold is limited, and more importantly, there is no solid N or NE sfc/BL wind to constantly drain the cold air to the N into SNE during the event. Winds are going to be rather light for a coastal storm, relatively speaking, so this is going to cause issues. Just before the precip starts in BOS on the NAM, the BL wind is 24011 and 6 hr later it is 1404. Does that look like a wind direction/trend that is conducive to significant snowfall? Also BOS buoy SST is 42 F. W/o solid ageostrophic flow and a mechanism to drain low-level cold air from the N into the heavier precip area, again, this is a big problem for ptype. You need this to offset relatively mild ocean temps. And what falls and SOG is likely to be quite different in many areas. So I would temper expectations here. Not a big storm (MEH for central pressure and deepening rate) and really no different than the piecemeal, nickel and dime events for snowfall we have dealt w/ so far this winter.

Can these stupid models make up their mind?? They have been oscillating back and forth for days w/ this system and the snow shield SE sections! What is it w/ this pattern that is making something that should be straightforward a challenge. It not like it is a monster sfc low! Oh, and the reason for the problem BL temps? Look at the 42 hr NAM sfc/pcpn fcst I attached. Um, no high pressure anywhere to N of us. Just low pressure, so no CAD! How often do you see that w/ a low pressure off the East Coast moving NE???

One item that stands out to me for the Sat event, when was the last time you saw that much snow forecast by the models w/ a sfc low passing well N in Quebec and sfc winds blowing the "wrong way" (SW) for a widespread accumulating snowfall, esp, in SNE? I can't recall an event quite like this. And the trough/sfc low is rather MEH. It seems counterintuitive, but the 18z HRRR and RRFS are in excellent agreement (snowfall 10:1 totals attached). Kuchera ratios are better for the higher elevations, showing up to a foot in srn VT. That is remarkable, given the synoptic setup! The odd and piecemeal/selective winter for New England snow events continues, and ern MA centered near Weymouth continues to be "flanked" on all sides, missing out on most events, while other areas are not doing too bad for seasonal snowfall, all things considered. And to add insult to injury, another oddity. It is the coldest time of the year, and a storm goes OTS, yet there are BL temp issues for ptype over SE MA and RI for the precip that makes it in?! This is what happens on Sun. W-T-F???!!! Maybe I shouldn't have said that, just drags down CoastalWx more!

57 still.

11 years

And in DC, it's not as good as I thought, at least on the N side of the Beltway. The downslope effect from the high terrain not far to the W stiffs me in Silver Spring a lot. Just E blows up big time on the Chesapeake dew point front/breeze. Seems like about 20 mi N and 20 mi S of me do well more often. Just location I guess. The thing is I am at 390 ft elevation, so not total downslope. Nevertheless, I have had some doozies and several supercells pass right over me. Had LTG hit the building and for the first time two years ago I actually heard arcing ZZZTTTT!!! (not click-pops, much louder and distinct) from a strike about 100 ft away. And thunder acoustics unlike anything I had heard before a couple of times.

It's not trolling. We go back and forth via email all the time. Oh yes, CoastalWx has given me the third degree before about how "we never get big tstms" here. Until 6/1/2011, then he had a change of heart! Then he got a +CG shock on his PC from a wicked close strike, and freaked when the outside transformer keep arcing. And the tornado in Weymouth in Aug 2023. He started to go "hmmmm" and then I showed him the long-term CG plot for New England, and how there is a local max right in his area S of BOS. High risk days often FAIL miserably, esp. in the Plains. I'd take a SLGT or MDT risk any day instead. My best chase days were in SLGT. Isolated supercells way better logistically, other than the chase hordes.

Wow, that much optimism so soon? Just how many times the op runs have had something "out there" in the long range, and never deliver. I don't see any real change to the NAMR 500 mean pattern UFN. In others words, MOTS (more of the same). "Cold 'n dry, kiss'em GOODBYE!" CoastalWx is getting so *sick* of these nickel and dime events, like what is coming up on Saturday. He can't even enjoy that in Weymouth b/c it will be too mild!

But the GDPS has something still?! Roll the dice. GFS/GDPS says YAY, and ECMWF/UKMET say NAY. With CostaslWx's luck this winter, he'll roll snake eyes!! LOL.

Moon dimly visible?

The CoastalWx dream scenario from the 12z GFS! Max right over Weymouth!!!

So finished a stretch of overnights ydy morning, and slept in long, so just looked at everything in the last hr, including previous runs. It's odd. You look at the solid full latitude 500 trough and it axis, and you wonder why a weak wave scoots out quickly ahead of the upper support, taking the baroclinic zone w/ it!!! Looking at 500 alone, it should much better at the sfc for a decent coastal. Also, now the models don't develop any real strong sfc low? Huh? Again, the 500 alone does not suggest this should happen! Big difference than 24 hr ago as well. The 500 cuts off *well* W of New England and is stronger than ydy, and moves over right over the region. That should promote a sfc low *not* scooting out to sea. However, it's not tilted below. The 700 low is co-located and goes right over the region, so we get dry slotted! But we never got any sig precip to begin w/! CoastalWx's worst nightmare! LOL. Moisture is quite limited w/ the upper low, so that will just mean half-decent snows across the mtns of NNE probably. Ydy was better actually, since the 500 low cut S of the region. And the two decent troughs that occur down the road, can't do much either, at least on the 06z GFS! The 06z ECMWF looks better for something this weekend. It's been piecemeal in regards to snowfall across the region so far this winter, no one storm can deliver widespread mdt-hvy SN. Just sub-regions, like LI to Cape Cod and NNE get localized decent snows. Now, we get a fragmented storm coming that that can't consolidate right!? I can see now why CoastalWx is really getting ticked!

I storm chased in the Plains most years 1992-2016.

Yes, IIRC, when you mentioned the Dec 1994 hybrid storm (really a 70 kt hurricane, and the it will likely get included as one officially once the Hurricane Reanalysis Project reaches the 90s - it is in the early 70s now), I went to CoastalWx, "how did you know about that?!" Well, a valid question b/c there was no snow w/ it!

06z GFS a bit odd. Fcst 15z Jan 16, it shows a nicely tucked back deep sfc low near ACK, yet the heavy snow area is surprisingly limited to the NW. 500 low is significantly stronger and still closed off one contour as it passes just S of the region.

He is just so much an uber snow weenie, probably the biggest one I have ever met, esp. in attitude and mood (up and down so much, depending on the pattern). I worked w/ him at WSI for a number of years, so I saw the entire gamut/range what it takes to be a snow weenie. We went back and forth on events so often. And even 10 years ago, he was still king of the number of posts on AmericanWx, and I used to say "where do you get the time???" And he would say, "a lot of the them on are other subforums like in sports" "Yea, right!, I would say!

I haven't followed the entire thread, so they may be content here already mentioned. This is a very complex forecast, and among the weirdest ones I can recall, or should I say challenging. This could be an odd duck event (CoastalWx immediately thinks of March 7-8, 2013)! It's not often you have two strong s/w troughs so close together in the East vying for "who wins!" And the eventual sensible wx outcome in terms of snowfall DCA-BOS may be something that is not apparent until it actually occurs, w/ some areas doing well and some areas not so well. CoastalWx will immediately go, "great, just another chance I get STIFFED for snow in Weymouth, just like I have been a lot this year!" In the broad pix across NAMR, it looks quite good. But as usual, it's all in the details. First, the good: 1) Mean trough position is solid in the E w/ axis good for a "CoastalWx Special." 2) Great amplified ridge western U.S. 3) A thing the earlier runs did not have is upstream ridging/blocking in the NATL. Now it does. It's not a strong block, but decent height anomalies are there. Downstream is just as important as upstream aloft! 4) 00z GFS/ECMWF/UKMET all show a quite strong closed 500 low well S either over the Carolinas or southern Mid-Atl. Something like that crossing the coast should result in decent sfc cyclogenesis. The UKMET makes the low go sharply negative, while the GFS/ECMWF keep it more neutral tilt. Now for the "problems": 1) The upstream kicker *right* behind it. Not good. And you can see on the 00z ECMWF 120 to 132, how strongly the kicker 500 trough deepens (120 and 132 hr ECMWF 500 attached). This messes w/ the lead 500 trough and starts to dampen it. This is not how KU snowstorms occur. 2) I don't like the moderately strong closed 500 low over central Quebec. It limits the s/w ridging ahead of the lead 500 trough. This should be over Hudson's Bay for the best weenie event. 3) The western U.S. ridge axis is a bit too far W for my liking, so the wavelengths broader than ideal. So you see, a truly complex forecast, much higher than usual for sensible wx specifics! Some musings/caveats: 1) Will the kicker trough try to "dumbbell" the lead trough and its sfc low more N? 2) The intense 500 low crossing the coast before it starts to dampen, how fast will the cyclogenesis be? How long will it stay tight/consolidated before elongation, if at all? 3) Just b/c 500 feature dampens, does not mean below that weakens much or at all. You can have a beast of a 850 and sfc low and not much more than a "dent" at 500 (Feb 1983 KU storm comes to mind). 4) Snowfall gaps or spotty. Look at 00z GFS, decent snow over the Mid-Atl, then a big gap PHL-NYC, and eastern New England does half-decent. GFS snowfall has the same idea and the UKMET to a lesser extent. Not the "smooth" snow event CoastalWx has been looking for (if Cape Cod gets crushed and Weymouth screwed - I can hear, "I'M DONE!!!" And so many on social media are acting like, "THIS IS IT, the BIG one!" just salivating over the 500 height anomalies colors (color table chosen make all the difference!), and saying something like, "something GOTTA happen w/ such wild anomalies like this! Big ridge in the W and intense trough in the East, good enough for me!" and just run w/ "end of days" hype. Well, we don't live at 500 mb, and just b/c the 500 looks great, does *not* mean the sfc is great. And they fail to see the finer details of the pattern I mentioned above that can totally ruin things.

I bet this is what has gone though CoastalWx's mind already!

Came across this. Sub in last time 6" and Weymouth MA, and we have the meme for CoastalWx's sentiment these days! LOL.

CoastalWx knows what's wrong with this map! "Why is it...?!"

Outstanding!