00:00Fire danger escalating across the interior west. Areas around Utah and into western Colorado are
00:06going to see some really volatile and extremely dangerous fire conditions Friday, Saturday and
00:12Sunday. We're concerned about the winds increasing and very low humidity. The vegetation has been
00:17dry out this way as well. So we have some big concerns. And our biggest headline this weekend
00:21here on really a national level, at least from my perspective, is this extreme wildfire risk in this
00:27part of the country, parts of the Great Basin, Utah into western Colorado. Now we've had some large
00:32fires. There are a couple of large fires ongoing right now, including a 50,000 plus acre wildfire,
00:3959,000 acres in parts of southern Utah. Fire activity producing some smoke. And a lot of this
00:46has been drifting east over the Rockies, kind of getting hung up in the valleys and so forth.
00:51But we're going to see a little bit more ventilation into next week as the winds pick up,
00:56sweeping the smoke over more of the plains, but also at the other end of the coin,
01:02increasing the fire danger. So we're going to look at some of the computer models and so forth. But
01:05let's take a look at overall this big trough that's going to set in. It's been a warm, if not
01:11hot,
01:12start to the weakened parts of the northwest. Temperatures are going to be dropping sharply here
01:16with this big dip in the jet stream. And while this offers relief, even some showers in the northwest,
01:23where there had been some fire danger, there will still be some fire danger up into parts of the
01:27Pacific Northwest. But that will be mitigated by increasing humidity and some showers out there.
01:33Areas adjacent to this, where you're not going to get that dew point payoff, you're not going to see
01:37the showers, you will see an increase in wind in some of these other areas down to the south. So
01:43again, parts of Colorado and Utah facing this very significant fire danger here out of this
01:50whole setup here. And overall, we're going to be looking at, again, a big drop in temperature to
01:55the northwest just briefly before we dig deeper into the fire danger. You can see some areas that
02:00have seen some significant heat earlier in the week, for example. There we are with a big drop from the
02:1090s to the 60s in some areas. Now, that is going to come with, again, a lot of relief for
02:17some. But
02:17if you're south of the area getting that payoff, it is going to be a very, very volatile setup here
02:25with fire danger escalating. And again, cooling down to the north, but the winds increase in this
02:31area right across parts of Utah and into parts of Colorado. So let's look at some of the details.
02:37Then we'll go back to our AccuWeather forecast for top wind gusts. So we can watch as this big
02:42trough sets in across the west, big pinwheel of low pressure digs in from Vancouver Island all the
02:48way down to Utah and, well, at least northwest of Utah and areas like southern Idaho, for example,
02:56under the core of that ridge, that trough of low pressure, the big trough sets in. And while the
03:02center of low pressure with this trough will be centered over maybe areas around Montana and
03:07eastern Idaho, we're really, really concerned about a volatile setup here where the winds aloft and
03:15near the ground are going to be aligning southwest to northeast, driving some very strong gusts across
03:21Utah and surrounding areas. So let's look at some of these other products. This is called the shift
03:25of tails. It's kind of a statistical look at winds and wind gusts with respect to normal. And when you
03:33begin to get up into, again, some of the deep reds and even hints of purple, that's where you have
03:38unusually strong winds. And again, this is based on an ensemble forecast of many different models.
03:45And in some cases, the same model physics tweaked with initial conditions. And then in other cases,
03:50you have different actual physics within the models. But when you produce, again, a forecast
03:54based on many different models, you get this strong consensus that the Great Basin is going to be
03:59extraordinarily windy this weekend. Saturday, Sunday, the shift of tails begins to come down a bit.
04:04So Saturday looks like the most unusual wind in some of these areas. And by the way,
04:09it's not just windy, but also low humidity. So this graphic shows the humidity anomaly. We're
04:14typically dry in the interior west this time of the year. But when you get into these browns on the
04:19map here, that's where you have unusually dry air, even on Wyoming and Utah and Colorado standards.
04:27So Saturday is appearing to be the time with the greatest juxtaposition between strong wind
04:34winds. And you can see in Colorado, the humidity anomaly, the departure from normal humidity,
04:40it gets even way lower than normal dry air in Colorado into Sunday. The winds will still be strong.
04:47The winds will probably be strongest on Saturday, still strong Sunday. But then areas that sometimes
04:51do see thunderstorms near I-25, you're going to be really dry with this downsloping dry wind coming
04:58across the spine of the mountains. And the humidity anomaly stays very impressive. So drier than normal
05:04in typically dry areas, Sunday, Monday, Tuesday. Top wind gusts here, this is cumulative. So as we go
05:10out at a time, it just holds on to the highest wind gust that the model forecasts. And you can
05:15see
05:16Saturday and Sunday, a lot of strong wind. These are in knots. So 42, 44 mile per hour gusts in
05:22knots,
05:2244 knot gusts would be like a 47 mile per hour gust for the most part. That is for specific
05:30locations.
05:31Those plots are for cities. They're for cities. So when we look at our forecast here, bringing back our
05:37AccuWeather forecast, instead of forecasting just for the cities, here we're forecasting for mountain
05:42peaks and canyons and some of these other areas. So you're going to see more impressive numbers here
05:47than those numerical plots. Remember, we tend to build cities and civilizations and communities
05:52in places that are a little more amenable to daily living. And a lot of the time,
05:56the benchmark through which those forecasts were for were for airport locations where you want to
06:01build an airport, generally safer spots compared to in some canyon that's especially prone to wind.
06:06But the fires often spread and they're initiated in some of these canyons and passes and up in the
06:11mountains. So that's what we're looking at here with some of our gust potential of 60 to 70
06:15miles per hour on Saturday in parts of Colorado and also into northern Arizona, which is not exempt.
06:21As we look at the wind carrying the smoke through Friday, the winds are not as strong yet. So we've
06:27got this kind of this accumulation of poor air quality. We're going to see a lot more ventilation
06:32in the days to come. So once the winds pick up, it's going to pull rapidly the smoke out into
06:38parts
06:38of the plains. So the risk becomes more about fire spread. And I'm going to close with a look at
06:43this
06:43optical thickness, the air quality forecast, atmosphere chemistry. We're going to see more
06:48smoke into more parts of the nation into next week.
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