MillvilleWx

I apparently ran out of likes to give this afternoon, which sucks. But, I want to say I love so much of these reports and pictures. Living vicariously through the sub

3.4” according to sister in Carney, MD at my old home where I grew up as of 5 min ago. Still dumping there, but a few sleet pellets are sneaking through recently.

Clarksburg is a beautiful microclimate for snow in that area of MoCo. Enjoy!!

Yeah. They are over 3” and it’s coming down in sheets. I wouldn’t be surprised if areas north of Germantown hit 4-5” before the flip. A place like Damascus where @jnislives could hit 5” at this rate. Im just living vicariously! Have fun out there

Absolutely pounding snow in northern MoCo according to my in-laws. They think they are going to hit 4” easily before any flip. Good storm for everyone. Enjoy!

I just realized you are in VA. Man, I need more coffee lol East-west gradient definitely works in your favor. 2-4" I think is a lock with a crust of sleet/ZR in the mix before any flip to rain. A true barrage of all the elements.

I would walk in knee deep snow with nothing on but a bathing suit and tank top while dragging a cinder block just to have half of one of those muffins. My goodness

I think 4" is possible for the western half of Howard Co if everything breaks right. Fingers crossed!

Even if the storm gravitates to the tongue of Theta-E along the coast, the phasing s/w with the ULL will allow for a negative tilt of the mean trough and the low will pull NW into the area. Absolutely nothing will stop that considering the 5H low track is well modeled at this point. Perhaps a tick east keeps the thermals from going to hell a little earlier, but there isn’t going to be a major shift to all snow for east of the Piedmont.

Ninja’d

It’s not. That’s pure snow. GFS algorithm is off there. Would say it’s an artifact of the site calculation. Wouldn’t worry too much about the GFS at this range. Stick to hi-res guidance and observations. It’s go time!!

One of the trends I like seeing on the RAP/HRRR combo is the downward adjustment of the surface temp for later this evening. It might not make it down to 32 for area east of Rt 15 beyond 03z, but it's trending colder west of their, and that spells a greater threat for ice. Also, the surface is extremely cold, especially the elevated areas where ice may occur while temp is between 32-34 degrees. Some slick spots will show up late, even for those in the rain. Keep an eye on that. Snow forecast looks pretty solid right now. I might bust a bit low on some of my ranges here if the trend holds. Ground truth to the south says this will be a better event than what we were anticipating 24 hrs ago. Love reverse, positive trends

Hey Trix! Suggestions for spots in the Keys; My wife and I love the Marathon area, preferably up near Duck Key on the north end of town. On the opposite side of the 7 Mile, Big Pine is always a nice spot, but Cudjoe Key is very pretty a little further down. Boca Chica near KEY is home to lots of people that work near the Naval Base there, but it can get super pricey due to proxy of Key West. Summerland Key is low key beautiful, but houses are smaller. I would go for a place like Marathon myself since the infrastructure is more built up. I will say the internet in the Keys is very hit or miss. AT&T has a monopoly down there basically, and they suck from what I heard. Didn't know if that would make a huge influence or not. Either way, that's one of my wife and I's potential landing spots for the NWS. Key West office is in my top 5 for now. Good private schools down near Key West, which is helpful if we have kids. Enjoy the time down there btw! Have a Hurricane for me on Duval

The NAM is that one friend who you know is gonna show up to the party, but when they do, they are drunk already

I like 4-8" for your area. Should come down pretty hard on the front end thump. Enjoy!

Pretty much none, but I think a longer period of ZR is possible for areas NW of the Piedmont. Rates may prevent high accretion, but temps staying at or below freezing could definitely occur

3km NAM actually jives with my forecast now. All the main players are well within reason. Love to see it. 12km NAM will come around on Tuesday

Good morning y'all If anyone wants to hear my forecast for their respective area, feel free to tag me and ask me and I'll come up with a forecast for snow/ice.

Final Call Slight adjustment to the snow and ice totals. Moved a delineation point a bit to the east to add more of Carroll/MoCo/Loudoun to the light blue shading representation. Let the chips fall today as they may. Enjoy everyone

The last time we had a pressure perturbation like that, it was after I had the three enchilada combo at Abuelo’s .

Hey guys! Just a heads up with the European output. It is a model that struggles a lot of time with the finer transition periods and is likely missing some ZR in the mix. There will likely still be some freezing rain to contend with, despite what the model signifies. This is where mesos come in handy. Some areas may see little ice, but other areas that typically hold the cold better will, so keep that in the back of your thoughts for the storm.

No problem! There's a method to the madness. One of the biggest things I utilize is the CIPS analogs with recognition of key features and then compare to previous events. I also have a pretty good memory for weather, so I remember setups with a similar evolution in certain areas of the forecast and weight that towards guidance. Blending guidance can be good for a complex situation, but sometimes intuition with the meteorology at hand can take precedence, especially for something historical or heavy climo based (Elevation dependent storms are big with this). Knowing your geography and how things typically unfold is important. Nailing forecasts exactly is extremely difficult, but the key is to stay within a bounds that can verify an Advisory or Warning when you put one out. As an NWS met, I think about being within reason and adjustments up are okay compared to adjustments down. Impact based forecasting. I want to be as close to right as possible, but not missing too much. In this case, it's hard to create a forecast when the transition time frame is uber important. That can make or break a forecast.

No problem! I think in a local sense that area will have a higher chance of being impacted moderately to major. The elevation factor is key for them with orographic enhancement of the precip locally while locking in the cold temps at the surface. Blended guidance was fairly bullish for their impacts, so that is key in this forecast from myself. Those topographic features are important for an event like this. I honestly COULD be a little low on snow totals across the MD line, but it'll be +/- 1-2" max, so I'll hold what I have for the time being. Stay safe up there!

Here you go y'all on my breakdown of the event. I am low on the north side into your necks of the woods, but I can make a separate map later that will give a rough estimate, or I can give a breakdown by towns/regions later via text. Happy tracking!

Alright y'all. I think I have time to delve into some details on this event and my forecast will be the last thing I post if you want to jump to it, now's your chance! Anyway, the setup is one that is complicated in the evolution, but the ground truth makes perfect sense meteorologically. Leading into the event, a cold HP over the top will deliver some pretty chilly air to the east coast with wedging down as far as northern GA. Traditionally, this would spell a pretty significant snow/ice storm for the piedmont and areas NW. There will be significant storm, but how we get there will determine the fate of the sub-forum. That fate will make some people sad, but it unfortunately is how it is and how we will roll, so lets dig in. First off, a potent upper-low (ULL) is currently traversing the south plains into the Arklatex and will round the corner this evening and move through the Deep south. This ULL will be matured and ready to go as it moves eastward overnight into tomorrow morning prior to making the turn NE after it enters GA. Over the N Atlantic, a beast of a low pressure will meander for about 12-18 hrs before slowing pulling eastward due to limited blocking over Greenland. This will allow for spacing to occur to our NE and weak ridge extension from the Atlantic over New England. This allows our HP to the north to scoot eastward, generating an onshore pattern for later in the storms life cycle (More on that in a bit). Off to the NW over Canada, a progressive shortwave trough will dig into the northern plains with eyes on the Midwest/OH Valley by Monday. This is what will cause a fair bit of commotion in the overall setup as the shortwave will "capture" the ULL over the east and begin to lasso it in place while tilting the trough negative as it wanders nearby. The associated surface low over the SE will motion to the north, then NW as the anchored 500mb presence will drive the low pressure towards the ULL as the features try to stack on top of each other, which is known as an occlusion. While this is all happening, the low pressure along the Atlantic coast will bomb out on its journey north, generating a prominent low-level jet (LLJ) in the lower confines of the boundary layer (PBL). Remember that HP that moved out into the Atlantic, well that in tandem with the developing LLJ will couple to create a "fire hose" effect of warm, moist air within the 850-700mb layer in the atmosphere. Figure Below shows a 7 StDev u-vector component. That screams warm/moist air funneling due west off the Atlantic. This is caused by the tandem of the base of the HP off the coast and the counter-clockwise flow around our surface low. This is what will be aimed at the area during the storms life cycle as it moves into the region. In the very beginning of the storm, the antecedent airmass is still pretty cold with near to below 0C temps through the column above. The leading precip will help wet bulb temps a bit with an initial start as snow, but the vigor of the LLJ will allow for the warm air aloft to quickly notch above freezing with areas to the SE seeing the transition first. Due to the increasing pressure gradient pattern and slow warming of the PBL, winds will increase areawide, leading to a mixing out of the cold surface inversion layer in place. This is why temps on models appear to "jump" to near and above freezing despite the cold air that was in place. There is no refresh of cold air to lock into place, so the warmer air above is able to mix appropriately and nothing can fight it back. As the storm begins its occlusion phase, guidance wants to have the stacking phenomena occur pretty much overhead or very close by. ULL's are dynamic and a mature mid-latitude cyclone has multiple parts that make it tick. As the low becomes stacked and the phase between the Midwest shortwave and ULL occur, the storm will drift off to the NE given the lack of blocking and the region will be on the backside of the flow at all levels. A strong vort max on the base of the mean trough axis will pivot through on Monday AM with a potential to kick off some light to moderate snow showers before pulling NE due losing the areal ascent on the underside of the trough. Way out west in the mountains, a continuous westerly flow pattern found on the western flank of the low/trough pattern will induce a period of upslope snowfall under cold upper-level conditions, leading to a higher-ratio powder that occurs over the traditional spots in Garrett/Tucker counties in MD/WV respectively. This will add to the synoptically drive snowfall with the storm, putting those areas in the best chance to reach double digits, despite the fact they will likely mix with sleet/freezing rain for a time during the storms height at their latitude. Overall, this is still a pretty high profile event due to expected winds and widespread impacts from N GA up into New England. As fate would have it, it's just not a pure snow event due to the lack of reinforcing cold air and the positioning/magnitude of features that occur overhead. That's just meteorology for you, but one cool thing to take away is the satellite will be pretty incredible, and will fit the textbook of a classic Norwegian Modeled Mid-Latitude Cyclone (Gotta love the Nords for their expertise on this matter ) In any case, there will still be winter weather in the area, and here's my thoughts displayed. I utilized a blend of NBM interpretation and hi-res guidance as they begin to narrow down the goal posts in terms of precip/timing/temps. There's a MEDIUM confidence on this forecast as there could be a slight bust either way, so keep an eye on those short term trends tomorrow to see what could be occurring. For now, look for a wintry mess with all the trimmings. Second Call (Potentially Final outside Minor Adjustments)