00:00So far this snow season through most of December we've had a big trough in the
00:05eastern U.S. that has held the cold in place and it's also led to a storm track
00:10that's been leading to rounds of snow in parts of the Mid-Atlantic, the
00:13Northeast at times. The storm track is shifting and with the forecast feed we're
00:18going to be looking at this late week storm. Who will see rain, who could see a
00:23little snow, and who's going to see some severe thunderstorms as well, and also
00:27who might see some meaningful drought relief. We are still, I know it's not the
00:30growing season, but we have a deficit in the terms of rainfall and we could
00:34benefit from some of that as well. So let's take a look at the big picture and
00:39overall the pattern is changing in a big way. As we move through the middle and
00:45latter part of this week the jet stream that had been dipping significantly
00:50across the eastern U.S. is no more and there's going to be a bit of a dip in the
00:53jet stream in the western U.S. but really we're dealing with a pattern that's
00:56much more, we call this zonal, west to east flatter flow. That keeps the cold
01:01bottled up to the north, in this case kind of favoring parts of western Canada
01:06and that's allowing this Pacific air to just kind of race across the nation and
01:10that's going to allow for a warming trend. It will also set the table for a
01:15storm track that's going to drive our next bigger storm system. I know we have a
01:20short-term minor storm system rolling through parts of the Midwest here in the
01:24short term but later this week the next big storm that rolls from the western
01:28U.S. is going to be creeping and moving through the Midwest and it's on a
01:32trajectory that will bring warmer air in. Anybody southeast of the storm track
01:37gets this flow from the Gulf and that's going to drive rain and even some
01:41thunderstorms into the mix. So we'll look at that here and as we take a look at the
01:45models, the overall pattern here is showing that the bulk of the storm system, it
01:50comes in two pieces. One of these we're not spending a whole lot of time covering
01:55because it actually drives south of California and in San Diego you're going
02:01to have kind of a near miss with just maybe a few sprinkles or showers on
02:04Tuesday but in San Diego in Los Angeles the next storm actually passes to your
02:08south. A lot of our American driven maps here with again our eye on viewers in the
02:16U.S. kind of focusing on this theme of drier weather to the south and wetter
02:20weather to the north. There's another storm track that's within southern
02:24branch of the jet stream just kind of quietly digging south of there so it
02:27doesn't quite make the American news as much but it will be a bigger story into
02:31northwestern Mexico and that's the initial contributor to this next storm
02:36system digging in across the Midwest. This is the thing that rounds the base of
02:40California passing through Mexico. It's going to be fed by more jet stream energy
02:45aloft coming in from the Pacific Northwest as well so you can see how it's
02:49kind of a one-two punch. The southern part of the jet stream that system scoots
02:54through but there's also certainly a lot of jet stream energy is going to drive
02:57into this here from the northwestern U.S. and that's going to be sending feet of
03:02snow to the Cascades of Washington and and Oregon as well. So we could show you
03:08that first and again mainly quieter in California heavy heavy snow up into
03:12Washington and Oregon here Wednesday Tuesday Wednesday and Thursday really
03:16and we're looking at multiple multiple inches of snow here and even multiple
03:23feet of snow in some areas. In fact I'm gonna briefly show you our forecast for
03:29snowfall here in the Pacific Northwest as I take us back to our graphics. So just
03:35take a look at this here over the next couple of days the northern branch of the
03:39jet stream sending 24 to 40 inches of snow to Snoqualmie pass 30 inches to 48
03:44inches that's what two and a half to four feet of snow to white pass. Stevens pass
03:49three to five feet of snow 36 to 60 inches big-time snow coming there and that is
03:54the northern branch contributor to what becomes the big storm system here at
03:59midweek and you'll notice with a storm track where it is if you are southeast of
04:05the storm track it's just gonna be too mild for any snow out there. So the whole
04:10eastern US this is gonna be a rain event for you when the moisture rolls in
04:14eventually but it will bring some meaningful rain and because this storm
04:18system is gonna be tracking across basically I 44 through Missouri then
04:23lifting north of there into Illinois and pulling north there's gonna be some
04:27instability when we talk about instability we're talking about warm air
04:30near the ground we've got a couple days in a row of record highs a few days in a
04:34row of near record highs in Texas and even into places near Vicksburg Mississippi
04:37on Tuesday that warmth will be fueling some instability so this is something
04:43called CAPE convective available potential energy and you can see we have
04:47a blank map for the most part early this Monday evening let's go ahead to
04:51Thursday though you can begin to see not a whole lot but some CAPE we're in the
04:56blues here so we're around you know in some areas between 500 maybe a thousand
05:00joules per kilogram of CAPE and again it's just a measure of of lift in the
05:06atmosphere the concept of warm humid air near the ground colder air upstairs the
05:11contrast of warm under cold driving these updrafts now in the spring and
05:16summer we're into the reds here in this time of the year limited CAPE but there's
05:21something out there and initially for the Thursday severe weather risk this is what
05:26we're highlighting parts of Arkansas southeast Missouri western Tennessee
05:30damaging wind and hail you'll notice we're playing up hail and wind with our
05:35the bullet points there on the left and then into Friday this the increasing
05:41chance to kicks up a notch maybe isolated tornadoes but not quite to the
05:45threshold that we're listing them yet four days in advance hail flash flooding
05:49damaging winds our concerns and if we go back to the model map here with CAPE you
05:54could see it maximizes from parts of Louisiana Mississippi into Alabama Friday
06:00afternoon and there's a nose of this here that moves north up into the second
06:04shade of blue which would be around 250 to 500 joules per kilogram it's not a lot
06:08if this were in the spring we'd be saying this is a very low CAPE event but here in
06:14the European models a little more aggressive we get into the third shade of
06:17blue here in an area north of Memphis so that's when we begin to think about you
06:21know 750 millibar 750 to a thousand grams joules per kilogram of CAPE that could
06:29bring us just a little bit more in the way of some thunderstorm potential now
06:32regarding snowfall with this one we're not going to see much all the snows in
06:37the northwest we could see you know maybe an interest of snow in some parts of the
06:40plains but the rainfall amounts will be more significant this is drought relief
06:44through the latter part of the week here localized two or three inches for some
06:48snowfall that's your forecast feed
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