The Iceman

Latest HRRR has the sleet line well south of PHL at 17z... Just saying

Are we using this thread for OBS or should someone start a new thread for that? Anyway we have clear skies here in Hopewell and temps are dropping like a rock. Temp is already down to 24 here and the forecasted low is 22. Seems like we are going to get down into the teens unless we cloud up soon. Anyone else radiating down temp wise this evening?

TT clown map... This is all pre changeover

When does the RPM generally change the city/95 over to sleet/frz? Also it seems like you think freezing rain will end up being a bigger deal than what's being currently talked about. .1-.25" of freezing rain on top of 3-4" of snow would be more impactful than an all snow 6-8" event imo. Do you think we will see a deeper warm layer than forecasted? Most guidance I've seen, it looks fairly shallow and leans more towards it falling as sleet with the low level cold in place but I definitely would like to hear your thoughts on that.

Yeah looks like we go over to light precip after that but should still linger another 12 hours or so.

Looks 10:1 to me, maybe a little under to include mixing

Euro says all systems go, should be fun from 7 am - 1 pm tomorrow. Not much mixing at all along 95.

12z IBM GRAF

12z HREF, this model has done really well this year.. pretty much mirrors my thoughts

Paul, is the wxsim usually pretty good at picking up the sneaky warm layers? That seems like a really low forecast based on the models and usually when you post it, it's on the high end of guidance. Do you think it's a red flag that it's showing mostly sleet?

I'm not too concerned about turning over too quickly, we have a really good airmass in place. I think we will thump hard from 12z to 18z and most places will see their 3-6" the before the pinging begins. I don't see this being a storm where we flip to sleet after only an inch or two but I've been wrong many times in the past

Looks good to me. A little higher than I'm expecting but Glen has wrote the book on Philly area snowstorms...literally I 'll defer to him.

Final call: 4-6" of snow and sleet along and west of 95 corridor up through 195. 8" lollipops somewhere in this area probably N and W where they don't flip. 2-4" snow/sleet/ possibly ending as light rain s and e of 95 and 195. edit: guidance is also hinting freezing rain may be an issue too. Gfs drops a stripe of .25" -.4" in spots just south and east of 95. Should be a solid winter storm warning event still, 4th of the year, not too shabby.

More like PTBS... Post Traumatic Bust Syndrome. It's a real condition where one assumes the worst based on past model busts in the same timeframe.

That one has an awful track for snow but the low level cold may still be enough for a light event. Something to track, it's gotten colder every run the last few days.

Has the waa thump still too. 4-6" in 6 hours from 12z to 18z... Noice! Hopefully the euro is similar and we can ride the old EE rule.

Also the nam has been pretty great of late, it sniffed out the last system being amped and west way before the other models. I'm not jumping off the ledge until it backs off or these trends continue. Any time you see such a drastic change on models like the gfs or rgem, I always wait another cycle before getting concerned.

You said N trend begins at 00z... This is the complete opposite

Rgem cut back precip totals almost in half though from 18z. That's a bit concerning. Hopefully just a blip.

Nope, looks good!

Down to 6" snow depth that should solidify into a glacier tonight before the next event.

I'm surprised no one posted that we got NAMD at 18z....whoa mama!

Same corridor imo but it's 95 in pa and NJ turnpike. Also, it doesn't turn into 295 anymore since they built the extension in bristol.

Eps is a bit further north than the op. You can tell it brings the mix line just south of 95. This is about the last run the ensembles are useful, so let's hope thats as far north as we get.

Seasonal trend has seen the mix line come further 50-75 miles north but this storm has been a bit different as confluence to our north has been modeled stronger as we've gotten closer which hasn't typically been the case. We will have to monitor tomorrow if the seasonal trend of ticking north comes to fruition. If it does, I expect the mix line to hit the Philly area and immediate burbs in lower bucks/montco/mercer. It is almost certainly going to be all frozen though at this point which is great news. If we see that north tick, and I put it at a big if at this point, I would probably lower totals around 95 to 3-6" but I still think this will meet winter storm warning criteria for 95% of the region even if we see more mixing than currently progged.