Bob Chill

I never bought the disaster that was showing up a few days ago. All the ensembles showed the same tpv drop and drift into eastern Canada + the -nao. I've never seen that type of progression just evaporate and flip to warm in the east. It didn't make sense. All we can do now is keep fingers crossed and hope incremental improvements continue. My gut instincts are telling me we're in good shape.

Truth. Last March looks great on the composites but too little too late. It can be maddening at times. When a great longwave pattern sets up 2-3 weeks too late it feels like such a ripoff. We haven't had a legit -ao/nao combo during prime snow climo since 2011. It's been a long time to put it lightly. Maybe this year will mark the reversal of blockless winters. Time will tell. It's still Jan so we're not racing the clock...yet

Very nice trends on the ensembles showing the fabled west based -nao may move in during Feb. Looks like the Davis Strait block builds next week over top of the TPV. Unfortunatlely the tpv is really strong so it bullies the block this go around. However, I'm starting to believe it's a warning shot that it might become a stable feature down the road a little. Always very difficult to feel confident that a real -nao is going to happen until its happening but you have to like the direction the gefs, eps, and geps are going. Even the pac is showing signs of getting right. Fingers crossed for now. I'm as sick of rug pulls as anyone...

We need a -ao/nao combo for a broad conus trough. 77-78 had that iirc. It's not all that uncommon. 95-96, 09-10, and 10-11 all had periods of a -pna coinciding with a trough and winter wx in the east. It's been a while though. Not all -pna's are terrible. Having a -epo is key for cold in the east with a -pna because it deflects the pac jet poleward and away from the north american coast. The -ao/nao suppresses heights in the east so cold continental air can stretch coast to coast in the US. One of the snowiest winters on record in my region happened back in the 60s and basically had a door to door -pna. You guys in the SE probably need a +pna more than my region though. Maybe someone can look back at years where there was a -pna but good snow in your area amd figure out what other features made it work. We may not even need to worry about it as the -pna on ensemble guidance may just be transient or never materialize.

Lol- i wouldnt jump to any quick conclusions. The next 10-12 days will feature several sig below normal airmasses and flow remains active from what we can tell. The neg pna (if it happens at all) looks to coincide with a very negative epo and modestly negative AO. While guidance has backed off on a stout -nao, there is no indication of a +nao. If anything the nao looks like it will still go negative or at worst neutral. One huge difference between a bad pac in Dec and what is progged in early feb is Canada is likely going to be an icebox. As long as the -epo holds (looks very negative in the long range) there will be very cold air across all of Canada. Any intrusions into the conus with be quite cold. In Dec the pac jet blasted every last molecule of cold air off the face of the continent. There's no comparison to late Dec/early Jan from what I'm seeing. Lastly, this new twist with the PNA could end up not happening at all or be brief. We'll just have to see how it goes. In a simpleton view there are only 2 kinds of winter patterns... a shutout pattern or one that could potentially produce frozen precip. After thursday it looks like a decent pattern for some snowfall in both our regions. Not amazing but far better than what most of winter has been like. It should also feature some pretty cold air. Before we worry about d14+ we have to see if we can score before the month is out or in early Feb. Final thought... We can still score with this type of -pna. Arctic air will be abundent in our source region. High pressures will move across to the north. This can set up CAD events or gradient overrunning events. There's no way to know specifics. Let's focus on the period in front of us because the ingredients will be available for winter wx. By the time we get through the next 10 days or so there will be brand new reasons to worry in the long range. Lol

The inverse JB model has near perfect verification scores. Backtested for decades.

Here's the eps d10-15 h5 and 850 means. I don't like fishing or golf when it's cold so maybe in March or we can meet in Phoenix in Feb?

Snow is always subject to luck and chaos so you never know until you are shoveling. However, I'm very confident on an extended period of BN temps. It's going to feel like winter and it's not going to hit and run either. If anything changes I'll come back and delete all my posts here. lol

GEFS agrees with the general idea that the op was showing in fantasyland. Overall, it's a very encouraging run for the SE and even deep south from D9 through the end of the run. Nothing is moving back in time either. If anything, the block is modeled to build faster than guidance was showing just 2 days ago. You guys are prob going to be pretty busy tracking stuff from mid next week through potentially the end of Feb.

You guys getting extra sleep right now? Everything remains on track for a significant blocking event beginning to take shape in just 6 days. Will take some time to evolve beyond that but no rug pulls showing up at all. Ens look rock solid near the end of the month. Fantasy GFS just spit out a sick full continental block and mid latitude wave train (around the entire globe. lol).

It could be dryish on the front side as the TPV drops in. It's a significant pattern change and very well could squash big juiced up storm chances for a time but the tradeoff is entering a backgound state that favors snow over heavy rain. EPS has Raleigh getting around .60 QPF from the 25th through the end of Jan. That's actually a half decent mean and doesn't indicate overly dry. I've seen mean QPF be as low as .10 for d10-15 on the EPS. That's an exceptionally dry mean. Right now it looks good enough. I just want to get rid of the heavy rainer west track pattern. You have to start somewhere... lol

Starting to get a steady flow of fantasy op looks that include the ens idea of a stout neg nao building inside of 2 weeks. Getting close to a lock that it's really happening. We'll know within a week. I've run through lots of data over the years and it's much more common in my area to get snow when the AO/NAO are rising upwards in negative territory. I have a hunch you guys do better with the opposite. One of your data heads can confirm. If that's the case, the last week of Jan looks really good for the SE.

Lol- i've been chatting with him for 12 years and have enjoyed most of his epic melts and rants. He's pretty funny honestly. When it comes to weather (snow in particular) I only trust myself. Lol Euro weeklies are fantastic start to finish but this panel is right out of the SE big snow textbook imo. It's almost NSFW

FWIW- 12z EPS has sped up the flip to a -NAO by about a day... It's less than 15 days away. Starts building d10 and goes from there.

This is very true with ops and also ops and ensembles struggle with timing of large scale pattern changes. Both our regions are dealing with what appears to be a stubborn WAR through d10 or so. That feature alone keeps my expectations low in the MA. However, it's all part of what should be a flip towards extensive high latitude blocking as the WAR gets pushed into the NAO region. Might take a couple storms to do it. Just no way to know this far out. IF (big if) you believe the GEFS' progression, north america goes from this at d10: To this at d15: What can go wrong? Everything... lol. What is my best guess? I do believe the ens guidance has the progression right but how quickly it gets to being REALLY good is up for much debate. My total WAG and best guess is the GEFS is too fast but it's coming anyway. We'll know in 5 days when d15 becomes d10. Ens have been pretty good through d10 but have really missed things (good and bad) beyond d10. I'm rooting for you guys (like always). I hope you guys get smoked before the month is out. ETA: 0z EPS looks very similar to the GEFS d15. GEPS is a little slower with knocking down the WAR. I generally stick to the EPS/GEFS combo and when they look mostly identical it usually means they have it mostly right. If they diverge or anything looks like it's going to screw things up I'll be quick to say as much. For now it's hard not to feel good about late Jan and possibly all of Feb.

My guess is some sort of lift or convection briefly mixed winds. Reminds me of the temporary breeze you feel in front of a shower. Today's precip was upper level and instability driven. Curious what direction the breeze was out of.

I will take the ICON more seriously with future storms. It picked up on the trailng piece first and also did very well with gradients and ptype etc. All models were too dry leading in. Overall the icon was pretty accurate and consistent.

We're close. I'm on the norbeck side of Rockville and have 11.4. Still snowing and sticking. Lol. Silver spring/wheaton/rockville/derwood did very well. We all have about the same. Very memorable storm.

The ironic thing is the reason the snow totals ended up being much higher than we thought is the same reason it wasn't cold smoke. Lol. I'm good with that. The afternoon snow was very high ratio.

The outer band moved around a lot but the 12z run today showed a bullseye out in winchester and wv panhandle. Was too low. Eta: euro missed the leesburg/upper moco/hoco jackpot between 18-0z. Upper level stuff is really hard to nail placement. That type of precip is almost always a nowcast deal

Euro nailed the band out there. Underdid qpf but placement was perfect. Euro well with qpf leading in. Was showing .65 iad/.70 dca/.50 bwi (going off memory). Not bad at all.

6.5 with round 1 and 4.9 with round 2 so 11.4". Winding down tho so a foot prob won't happen. What a disaster.

Prob a transformer if i had to guess. Not seeing any strikes on lightningmaps.

The icing would be for the big moco-hoco deathband to hold together and rotate through DC as the pivot completes. My guess is no but every conservative guess i've made has been wrong

Afternoon moco death band(s) exceeded my wildest expectations. Incredible storm on all levels. Tracking for days and serious overperformance. Rare occurrence...