00:00Here in the forecast feed we're going to talk about temperature extremes. We're going to be
00:03within a few degrees of record highs in the southeast for a day or two and we will be
00:08breaking record highs in parts of the northern plains and the northern rockies
00:11but you may be surprised which of those areas will be hotter to achieve record status. If you're
00:19really dialed into the weather maybe you're not going to be surprised but it's been hotter in
00:22Casper, Wyoming than it has ever been in Miami, Florida and this is something that is not new.
00:28It's been this way for many many years for centuries upon centuries so what's this all
00:32about? Why can it get hotter in Bismarck than in Miami? By the way the record high, the all-time
00:39record high in Miami is 100 degrees. The all-time record high in Bismarck, North Dakota? What do
00:44you think? 102? 103? 114 degrees. So again we've never been above 100 in Miami since the late 1800s.
00:52We've never been above 114 in Bismarck in the past century plus. So let's look at this. What's
00:58this all about? Why does water moderate air temperature so much? So water has a high specific
01:06heat capacity. It has a high specific heat or high heat capacity, you could say it either
01:11way. Water is slow to warm and slow to cool. It takes a long time to warm up. The water
01:21temperature
01:21just barely changes day to day. The sand, if you go to the beach, man that gets hot if
01:26you're in the dry sand in the middle of the afternoon. And then it chills down a lot at
01:30night. And the water moderates temperatures in coastal communities. It really does in a
01:37significant way. Here we are late this week. It's going to be warm and humid. We have steamy
01:41on the map there in the parts of Florida. And we will be pretty darn warm. But to get to
01:46record territory in some of these areas, like in Tampa, you have to be about 5, 6, 7 degrees
01:54above your historical average. If you're only 5, 6, 7, 8 degrees above average in Bismarck,
01:59you're not even close to a record. Because of that, in Sarasota, we've been to 95. That's
02:04the record. We've been there six times on July 9th. I'm checking the date there for Thursday,
02:12July 9th. These records are all specific to July 9th. So we may add our seventh journey
02:17to 95. There are days, a couple days in August, where Miami's average high is 90 and the record's
02:2294. So four degrees above the average can take you to record territory in some of these areas
02:27in the south. Now you go inland into Raleigh. That's where you have a little bit more of
02:32land protection. You're not right up against the coast. So you can get warmer there in Raleigh
02:37than in Tampa or Fort Myers with a pattern like this. So we're dealing with near record highs
02:41in a few areas here. But I wanted to contrast that with what's going to go on this weekend.
02:47This weekend, we actually cool a little bit in the southeast, and the northern plains will heat up.
02:52So take a look at this. Some more record highs. Look at these records. This is Montana and Wyoming,
02:58areas that most of you probably associate with winter and snow and blizzards, and rightfully so.
03:05These are just daily records. The record hottest July 11th. We've been to 101 in Lander, Wyoming.
03:09We've been to 102 in Billings and Sheridan. We've never been that hot since the late 1800s in Miami.
03:15And here we are up near the international border and up in high elevations too, in the high plains,
03:20getting up into the foothills of the Rockies. So what is the deal here? These landlocked areas
03:25are not protected by water. And in the middle of the continent here, you're going to be in the
03:32middle of the continent. There's so much land around you. There's nothing to really moderate
03:36the air temp within a thousand miles of some of these areas. And you've got the Great Lakes,
03:42and they offer some cooling a little bit. But again, Florida, at least coastal Florida,
03:46it's protected by water. Some of you may be surprised by this, just a separate conversation,
03:52but just talking about water moderating the air temp. In the fall, the last places in Pennsylvania
03:57to get a freeze are typically the city of Philadelphia. You've got the urban heat island,
04:01you're down at sea level, and you're southeast, and the Erie Lakeshore. That's why there are so
04:05many wineries near the Great Lakes, because the water protects those areas right along the lakeshore,
04:10and that keeps the temperatures a little more moderated. So the message here, if you're in the
04:14middle of the continent, your extremes can be wild. Let's look at the models. Where are the extremes
04:20this weekend? Well, the heat's going to be building. Here's that 594 line. This is a mountain of air.
04:27Hot air is expansive. And when air expands, these thickness lines, these height lines in the atmosphere,
04:35you have to travel higher up to get to 500 millibars. So it's just, think of it, I know it's
04:40complicated. Think of it as a mountain of air. And this mountain of air is going to expand, almost
04:44if you were to think about this as like a contour map, a topographical map. Look at this. We added
04:49a new
04:49line here. Here's the 594 thickness line, or the height line for 594, 594 decameters, before you
04:55reach 500 millibars in lowering pressure. And then you get up into this 600 decameter line. This is a
05:01really big zone of extremely hot air across the Northern Plains and the Midwest. And you're noticing
05:10that this is really far from the ocean. So I know there may be some localized cooling in Duluth,
05:16or Marquette or Houghton, Michigan. But if you're not near the lakeshore, you are far from any
05:21meaningfully large body of water. And it's going to be really, really hot. This is why Amarillo can
05:26get so much hotter than Galveston, Texas, because you're far from land. Well, we are dealing with a
05:31sprawling heat dome that's going to be taking over here. And we'll be looking at some more graphics
05:35here in a minute. But you'll notice a couple of things here. This heat dome strengthens in the
05:41interior west over the Four Corners region. Then it expands up into the Northern Plains. And then it
05:48begins to, while the core of this stays in the Plains, it does extend, it's going to extend all the
05:56way into the Northeast. So Tuesday and Wednesday, we're going to get hot again in the Northeast,
06:00but only for a couple days. And it won't be as long as what we had, or nearly as extreme
06:05as what
06:05we had last week. And then a trough sets in, and that cools you back down. I'll draw a cold
06:10front
06:10just to help illustrate that point. And the heat dome is again restricted back into the area near
06:15Interstate 25 in the High Plains. So how hot are we looking here? I showed you a few of those
06:20examples,
06:20but with our forecast for Saturday, those were record forecast highs for Saturday, or near record highs.
06:26The all-time record high in Salt Lake City is 107. We've been there four times. We'll be close
06:30this weekend. We're forecasting 105 on Saturday, which should at least be near a daily record.
06:35Daily record high is 106. But look at the Dakotas. I'm seeing forecasts of 109, 112 in Eastern Montana.
06:40Not as extreme in the European model, but it's going to be really hot out there. And you'll be back
06:45into
06:45the 90s early next week in various parts of the interior Northeast and I-95 as well. That is your
06:50forecast feed.
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