00:00Well, we have a few moving parts here with the forecast feed, a couple of different waves
00:05of low pressure, one associated with a cold front that's going to deliver some colder
00:10air back into the northeast, another one that's going to be kind of a battle between a strong
00:15ridge of high pressure over northern New England, eastern Canada, and an advancing disturbance
00:20that doesn't have a whole lot of firepower initially, does have some moisture, but not
00:25a whole lot of firepower, and then behind that, a stronger disturbance is going to bring
00:28an aggressive push of warming that will also spark some freezing rain and some sleet.
00:34Let's look at all this here, just to give you kind of an overview, some of the bigger headlines
00:40here that we're facing.
00:41It's tied to the Sunday night, Monday in the Midwest, and then Monday to Tuesday in the
00:47northeast, mainly Monday night and Tuesday, the snow ice potential.
00:51There's a little bit of setup work that we have to do before we really get into that forecast,
00:55and one of these items here involves the return of cold air, because we're actually
00:58going to be warmer on, we're going to be warmer on Saturday in advance of this inbound front.
01:05So I know the big feature on the map for Saturday is a cold front that we're plotting.
01:11Here we are in the evening, and by then the cold front is going to be moving in to the
01:15I-95,
01:15but it's warmest right before that wind shift, and a lot of the time temperatures rise and
01:21rise and rise right up to the front that the wind shifts and right before the front arrives.
01:25So look at these temps, I see 54 in Philly, we're going to be around, well, in the early
01:30afternoon, the dam's a little less aggressive with the warmth, but I would hedge toward the
01:35warmth, 54 in Philadelphia at 1 p.m.
01:38Here you can see the European at 45.
01:40This is the pattern where the warmth usually wins.
01:44We don't have any leaves on the trees.
01:46We do have a warming trend for the southwest, that aggressive breeze.
01:50The only argument against this being a very warm day would be some of that snowpack, and
01:55that snowpack is dwindling in some areas further south.
01:58Tight temperature gradient between New York City, where there is plenty of snow on the
02:01ground, and D.C., where it is gone on Saturday.
02:04Regardless, a cold front swings in, and look at what happens here.
02:07Sunday, colder air advances even at 1 p.m.
02:10The pink line there, that little red line, I'm going to try to highlight it here, this
02:14thin red line, that's the freezing line, and you can see that, again, we're going to be
02:18back in the 30s for some of us, and turning colder through Sunday evening, Sunday night,
02:23and cold air returns for Monday.
02:24Monday's a colder day, but there's strong high pressure with that.
02:29So, first things first, there's a weak disturbance that follows our eastbound cold front, and there's
02:35not much to this.
02:36It's on Sunday, Saturday night, Sunday morning.
02:38There it is, and I know your eye is drawn to the blue, mine is too, but just keep in
02:43mind, a lot of the actual blue, the accumulating snow, is way north and west of I-95, unless
02:48you're in Boston.
02:50Maybe in New York, we see a little bit of a mix.
02:52The trend is a little warmer with this one Sunday morning.
02:54I know I mentioned that we're going to be colder, but the push of cold air may not fully
03:00be in place here to preserve snow in Philadelphia or New York without a little disturbance, so
03:05just be aware.
03:06Weak disturbance, there will be some snow out there, maybe an inch plus into the Berkshires
03:10and other areas north of New York City, a coating to an inch possible just north of New York
03:14City.
03:15I'd hedge against an accumulation in New York with that.
03:17But that's Sunday.
03:18That's Sunday.
03:19What really has had our attention has been the two systems that follow that Sunday disturbance,
03:24and here when we look at the two disturbances here in the jet stream, one of these, it's
03:32a subtle, it's not a powerhouse storm, but here we have a ripple of energy in the atmosphere
03:37on Sunday night into Monday moving into the Ohio Valley, and that moves east.
03:41But you'll notice it really washes out.
03:43Those colors, the vorticity wanes, and we go from the higher levels of vorticity to the
03:50weaker levels of vorticity, we're talking about spin in the atmosphere, basically this system
03:55erodes as, and there's a pretty good trend here.
03:58You can see it just kind of weakens.
04:00There's some energy in the jet stream aloft to the north, but look at what's going on
04:03up there.
04:04We've got a strong high pressure system.
04:06We're going to plot this with the big blue H there.
04:10And it appears the trend is increasing that that's going to probably win out from the
04:15Pennsylvania Turnpike north for Monday's daytime precipitation.
04:19I don't think we're going to see much precipitation along the Pennsylvania Turnpike because watch,
04:24and again, there's still some disagreement here in the models.
04:26We're going to see some accumulating snow in the Midwest parts of Missouri Sunday night
04:31into Monday, but you'll notice high pressure squashes this south, and most of this snow is
04:38going to be in decline as it makes a beaver line from southern Ohio into Maryland.
04:42It probably will bring some light accumulations of snow into Virginia on Monday and Monday
04:47evening.
04:48Here's another opinion.
04:49Here is the NAMM, and I'm looking at this system here in Missouri, the NAMM Sunday night.
04:56Keep an eye on that.
04:57Here it is in the NAMM.
04:59That's the pink there where you're looking at freezing rain.
05:03And now the NAMM only goes out for 84 hours, so it takes us to Monday evening.
05:06But you can see a declining trend in precipitation even into Indiana with a big, strong ridge
05:11of high pressure even farther south, dominating the weather on Monday evening into I-95.
05:18So again, not much to speak of there for that first wave.
05:22And then here we have the European, and there's some light precipitation in Indiana and Illinois.
05:27It never makes it into the northeast until the second wave rolls in.
05:31So this is what we're doing with our forecast for that first wave.
05:35Here we are Sunday into Sunday night.
05:38It's Sunday night when it moves through parts of Missouri and into Illinois, and then it kind
05:44of runs out of gas.
05:46So overall, here you can see our forecast for snowfall, and we're cutting it off basically
05:53at I-81.
05:54We're not expecting this to bring much east of I-81 into Monday.
05:58We need to wait for the second disturbance because that ridge is just so darn strong there
06:02in the northeast.
06:03So the second disturbance comes in with an aggressive warm front that lifts north, and
06:10that really displaces that ridge of high pressure.
06:12That's out of here.
06:13That goes offshore, out over the Canadian Maritimes, and gone.
06:16So Tuesday, that's the most disruptive day for the Pennsylvania Turnpike northward.
06:20And that pink zone, we're looking at ice.
06:23We have ice.
06:24We have a transition from a little snow to freezing rain.
06:27Well, maybe a little snow to sleet to freezing rain.
06:30It's a pretty good agreement here.
06:31And then over to rain.
06:32So that's what we're most concerned about.
06:34I'm going to jump back to our graphics here.
06:36Monday night, that begins to make a push into the region, and I don't want to overpromise
06:40the arrival time given that strong ridge of high pressure.
06:43Tuesday's the day with a sloppy ice over to rain transition in many areas from the Pennsylvania
06:49Turnpike north.
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