00:00Here on the forecast feed we have a lot to talk about this weekend. We're going to focus on the
00:04short term. There is potential and the likelihood of some midweek snow and ice in the interior
00:09northeast as well coming up into next Wednesday. A lot of questions following that the Valentine's
00:15Day weekend storm. A lot of debate with that one given some ill-timed features that would be a
00:22contributor to that one. But let's focus on the short term here just because we have our hands
00:28full with some bitter wind and arctic air that will be preceded by snow and snow squalls and a
00:33tricky feature to track in southern New England this weekend. Saturday, snow with an inverted trough,
00:40an upside down trough. Let's take a look at this here. Big picture as we jump into just the grand
00:46scheme of things here this weekend. We have a big lobe of very, very cold air. Some of the coldest
00:52tear the hemisphere with cross-polar flow coming down, approximately cross-polar flow coming down
01:00from the North Pole here. In reality, I think it's a little bit more kind of like this. But again,
01:05just a really serpentine pattern in the atmosphere. We've been dealing with some record warmth in
01:11places like Rapid City, South Dakota, big ridge in the west, big trough in the east, and it's been a
01:16remarkable pattern. Let's look at the models here. And overall, upper level flow. I'm not going to
01:22show too many different models here just for the upper level flow. There's not much debate what's
01:27driving this system. Here we have the long wave pattern, long wave ridge and trough, and the short
01:35wave that's bringing this disturbance to light here. It's being driven by a spoke of energy rotating
01:42around the base of the long wave trough. And it's a pretty feisty little system here, bringing some
01:47snow from Chicago into Indiana and Ohio and Michigan, and that's racing southeast. The bright
01:53colors here represent where we have extra spin in the atmosphere. We call it vorticity. And if you're
01:58east of one of these batches of bright colors, approximately as we begin this, if you're east of
02:04there into parts of Indiana, Ohio, Michigan, you have a lot of lift in the atmosphere, and that means
02:09snow production with this current pattern. And this dip in the jet stream, this little kink
02:13here where you can see the height lines just kind of kinking southward, there's your trough,
02:20and it reaches the mid-Atlantic coast here this Friday afternoon and evening. And it'll be continued
02:25to be supported by this deep trough off to the north that will kind of consolidate into a really
02:33blossoming system just offshore. And an area of low pressure at the surface is going to get going
02:38in a big way here. But the main batch of surface low pressure is going to be just far enough to
02:44the east that you'll notice some of the heaviest precipitation will be offshore. There you can see
02:49some heavy snow. Look at this offshore. But I want to draw your attention to southern New England here
02:55because we're concerned after some snow squalls blitz through the northeast with the Arctic front
03:00this Friday evening and Friday night. And you can see here I'm going to draw the line here
03:06approximately along the Appalachians. If you're west of that line, you get upslope flow. It's actually
03:12flow almost directly from the north, but it's still upslope for West Virginia, western Maryland,
03:17the Laurel Highlands of western Pennsylvania. You're going to see some prolonged snow amounts there,
03:21three to six inches. But then we get into the weekend and Saturday, and we got this tricky feature
03:28here that's a concern. And Bernie's been talking about the Norland Trough, and it's an inverted trough.
03:37This is something that is a feature that's tricky to track, but sometimes there's a feature called a
03:44Norland Trough when it's typically a zone here where there's a tight wind shift on the northwest side of a
03:53coastal low pressure system. So here we are with our strong low. It's well offshore, 986 low. This is
04:00Saturday around midday, and it's far off to the southeast, so it's not the ideal position for a
04:05big east coast storm by any stretch of the imagination. But amid a zone where we're generally
04:10advertising a broad one to three inch snowfall forecast, there's going to be a zone here where
04:16there could be a tight wind shift that could focus a little more convergence, a little more lift in
04:23the atmosphere. And if we generally focus our eyes on the wind and the isobars here, you can see isobars
04:30here, and there's going to be a pretty tight zone here where we see winds coming from the east to
04:37shifting strongly to a wind from the north. So it's kind of a hard left turn this wind is going to be
04:43making across part of the area somewhere in southeast New England. And that's often a zone that focuses
04:51more snowflake production, more lift in the atmosphere in a small, it might only just be one to three
04:57counties that sees the payoff from that tight temperature, that tight wind shift, I should say. And you can see
05:06the models are trying to hint at something like that. So here's the GFS Saturday afternoon. And this is
05:12highlighting an area near Buzzards Bay and up into an area near Boston. If we look at another
05:17depiction, here's the NAM. And it's a little bit more fickle. It generally focuses something kind of
05:22like that feature down off of Montauk Point and offshore where it wouldn't matter. Here is the NAM.
05:28Here's the European. And it's a little less dramatic, but there's still a hint, a suggestion,
05:33kind of the corner here where you see this wind. You're going to get some ocean enhancement here,
05:38almost like lake effect snow, by the way, that will contribute to some of the snow in eastern
05:42Massachusetts and in the GFS AI. So we got to keep an eye out for this. And what I wanted to show you
05:48is the GFS produces a 4.4 to 5.5 inch snowfall from Boston up into coastal New Hampshire. The NAM,
05:57more aligned with our forecast of one to three inches, with that 4.6 near that feature off of
06:02Montauk Point. And the European, you can see hints near the Worcester Hills and down to an area just
06:08east of Providence, Pawtucket, where there's potential for a little more than two or three
06:13inches. So as we bring this back to the models here, or back to our product here, I'm going to
06:21turn the models off here and just bring it back to our official snowfall forecast. What I want to
06:26communicate to you is that we're forecasting a widespread one to three inches for most of New England. But
06:31keep in mind, I'm going to make myself disappear. Keep in mind, there is potential for somebody in
06:38an area from generally Boston down into eastern Connecticut, somebody out there could see a
06:43localized one to three county area that sees more than three inches out of this system. That's your
06:48forecast feed.
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