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00:00:00:09 – 00:00:20:28
Speaker 1
Welcome to today’s visit Satellite Chat. And what we’re going to discuss is the recent, winter weather and cold air, outbreak that is, been over the course the last few weeks here. And one of the events associated with that is a significant lake effect snow event that occurred, last week. So that’s what I’m going to discuss here.
00:00:20:28 – 00:00:46:25
Speaker 1
First, this is the 850 Millibar, temperatures from the Nam along with the 850, Ray, the 12 from 12, the at seven of January here. And, you can see across the Great Lakes here. 850 Millibar temperatures around -28 or so. Actually a little bit colder to the south down here at, Pittsburgh.
00:00:46:25 – 00:01:13:18
Speaker 1
It’s -32. The actual, observed temperature at 850 was -27.7, which is the 13th coldest on record, from the Buffalo, radio on radio science site here. So it’s, pretty important to note how cold that is. And of course, if you have, open lake waters, that’ll make for some extreme instability that sets up here.
00:01:13:21 – 00:01:39:09
Speaker 1
The other thing to note is the winds. And you can see the winds are plenty strong, around 40 knots across, Lake Ontario and Lake Erie here. So that’ll enable you to, get the sensible and latent heat fluxes into the boundary layer deep in the boundary layer and develop, clouds and lake effect snow here. Also note the fetch is favorable here, with a west southwesterly, direction.
00:01:39:11 – 00:02:02:03
Speaker 1
So let’s go ahead and look at the visible imagery for the day before. And the the reason I want to set this up with some, imagery from the day before is because we do have some ice cover to analyze here. And, Lake Ontario was mostly open during this particular time. However, Lake Erie did have some ice.
00:02:02:03 – 00:02:28:04
Speaker 1
So as I slowly go through this loop here, hopefully you can see the lake ice over the southwestern portion of Lake Erie over here. And, just northeast east of that, where you have the sensible and latent heat fluxes. As you can see, cumulus cloud development and in, abandoned orientation from northeast to southwest. So, so you can see pretty clearly where the ice cover is.
00:02:28:06 – 00:02:56:12
Speaker 1
And, roughly, half or so of Lake Erie was open and and roughly half or so is it has some ice cover on it. So it was a factor here over Lake Erie. Not as much. So over Lake Ontario. Let’s go ahead to the, the day of the event here, the 7th of January. And I’ll start off by showing, surface observations along with the visible imagery.
00:02:56:14 – 00:03:20:11
Speaker 1
And first note the temperatures, very cold, around zero to a little bit below zero around the region here. And the warmest temperatures that you see. Go ahead and stop it on this frame right here are actually downwind of the lake. So right here at Watertown at nine degrees is warm, relatively warm because they’re getting the, warmth off the lake here.
00:03:20:12 – 00:03:50:04
Speaker 1
Similar story for Buffalo here at three. But otherwise you see very cold temperatures across the region here. If I snap off the surface observations and we focus in on the visible imagery here, you can readily identify the, lake effect snow bands off of Lake Huron, Lake Erie, where there is open, water here, that that does play a role here in terms of, how much lake effect snow they were getting.
00:03:50:06 – 00:04:15:03
Speaker 1
And, Buffalo actually had around two feet of snow. And that’s pretty impressive considering the amount of ice cover on the lake. It probably would have been quite a bit higher, had the had Lake Erie been completely ice free. But as it was, they still had a good event there because of the favorable fetch. Pretty much running a southwesterly flow there across the long axis of, Lake Erie.
00:04:15:05 – 00:04:51:00
Speaker 1
Meanwhile, over on Lake Ontario, over here, you can you can see, the start of, relatively, impressive looking band over the center of Lake Ontario. And, what? I’m going to do it. Let’s go ahead and attempt to draw on here. Just some, some, some, features to highlight here. So, the the most impressive band, most impressive, single band is fairly narrow, and it’s pretty much long, gated like this here.
00:04:51:02 – 00:05:16:18
Speaker 1
And then just north of that, there’s another, smaller band, a much more weaker band just to its north. And then there’s another band just to its south here as well. So, what’s going on? As you can imagine, various solenoid solenoid circulations here with the most impressive one surrounding this, intense band, which pretty much oriented the South just south of Watertown for a good portion of the day.
00:05:16:18 – 00:05:42:08
Speaker 1
We’ll look at the radar imagery next to, analyze that. But one of the more interesting ones is this band to the south here on the southeast portion of Lake Ontario. This actually begins over Lake Erie, where you have the higher equilibrium level here due to the, latent sensible heat fluxes. And that continues across the land here through the Rochester area.
00:05:42:10 – 00:06:07:15
Speaker 1
And then as it goes over that, a very short portion of Lake Ontario, it’s already a fairly or a relatively elevated, boundary layer. And that just enables it to grow that much faster, even though it’s a very short fetch of Lake Ontario here, it’s already been enhanced. So the interesting thing is, if this was completely ice covered, if Lake Erie was, this probably wouldn’t be here.
00:06:07:15 – 00:06:32:11
Speaker 1
It’d be much less of a signal over the southeastern portion of, Lake Ontario. But like I said, the most impressive band was this one right here. And we’ll look at that in some more detail. But, first I want to switch to, synthetic imagery. And this is the synthetic, 10.35 imagery. So this is the, let me erase my drawings here.
00:06:32:13 – 00:06:56:29
Speaker 1
This is the, synthetic imagery from the initial wharf, which is that, four kilometer resolution. And as I slowly loop through this here, this goes up through the early afternoon hours from, so it goes from 9 to 20 Z on the, seventh. And, a few things to note. First, the, various lake effect snow bands across the Great Lakes.
00:06:56:29 – 00:07:24:16
Speaker 1
You can readily see, across Lake Ontario. You can see it has a pretty good handle and, lake effect snow band that’s occurring off, Ontario and then off Lake Erie. You can see you can readily see which portion of it is, frozen or at least has ice cover, according to the, model analysis versus the places that have, the colder brightness temperatures where you have clouds associated with lake effect snow.
00:07:24:16 – 00:07:56:19
Speaker 1
So you can see it’s a relatively, shorter than what it could be if there was no ice here. The other interesting thing you can see is between the the new model runs from right here to right here. You can see the change or the uptake in the ice cover from the model output here. So I’m not sure exactly what resolution the model output is or I should say the the input of the ice cover is that they use in the model here.
00:07:56:19 – 00:08:21:08
Speaker 1
But the model itself is for kilometer resolution. So it is going to be smooth out some compared to what we would actually see in the satellite imagery, where we see some break up and a distribution of ice cover. So nevertheless, it’s you can still glean some information from it here in terms of, learning where the ice cover is and, and the relative, amounts here.
00:08:21:08 – 00:08:49:23
Speaker 1
And when it gets updated, you can see that much more ice cover that’s updated here in the model. Okay. Let’s go ahead to, the radar reflectivity here hourly just because I want to, time match with the RTM, which, which is the surface winds and surface temperatures here. So this is at 11 Z. And you can see the band is set up in this, fashion right here, south of Watertown, which is, where my cursor location is right here, immediate.
00:08:49:28 – 00:09:18:17
Speaker 1
Immediately, you should notice the much warmer surface temperatures over the lake, as high as 20 degrees. Right over the lake. Exactly what those temperatures are over the lake. We don’t really know. However, during the time, during this time period, there is a field project that’s going on, called owls. And they were collecting additional data. So we’ll be able to see finally, if these surface temperatures are they’re pretty close to reality or maybe even, maybe a little too cold.
00:09:18:18 – 00:09:39:01
Speaker 1
We don’t know. So that’ll be interesting. The thing, that will come out of this field project. Another thing to note is note some of these wind barbs approaching 50 knots over the lake. So when you set up these bands, you’ll get a lot of, convergence and, you’ll get greater wind speeds. Just to the, the sides.
00:09:39:01 – 00:10:06:12
Speaker 1
Or in this particular case, the north and south of these intense bands that can set up. And that helps to actually lock in the position of these bands, these convergence. But then these convergence zones and actually develop as a result of the deeper boundary layer, the sensible heat fluxes and then the circulations that develop associated with so that’ll be another interesting question is exactly how strongly those wind speeds get across the, the lake.
00:10:06:12 – 00:10:26:18
Speaker 1
And we’ll be able to answer those hopefully with the additional data that we’ve collected. So let’s go ahead in advance and we can see the band does move northward during the day slightly. And then it kind of sets up, to this area just south of Watertown. The maximum amount of snow observed was, five feet, just a little bit south of Watertown.
00:10:26:21 – 00:10:52:27
Speaker 1
And there were other values that were pretty close to that 54in, but in a extremely narrow band. Also, the reason you see this enhanced higher reflectivity, going well inland is the change in elevation, that there’s a rise in elevation of about 2000ft and, 35 to 40 miles higher. So we have a considerable upslope influence here as well, which obviously will contribute to those higher, snowfall values here as well.
00:10:52:29 – 00:11:19:08
Speaker 1
And the other thing to point out is you can easily see those three bands that I, that I identified in the visible, satellite imagery, the weaker band. Well, to the north, the intense, very narrow band just south of Watertown, and then the weaker band to the south with origins of an elevated boundary layer, coming off of Lake Erie and going over this short portion of Lake Ontario.
00:11:19:10 – 00:11:28:16
Speaker 1
Okay. Before I pass it over to Scotland Room, to talk a little bit more about this, I want to ask if there’s any questions or comments.
00:11:28:18 – 00:12:00:11
Speaker 2
Yeah. Hey, now, Brian, Earth Networks, put out a blog post about this event, indicating that the, total lightning data apparently did a good job of, indicating where the greatest, instability and snow rates were. I haven’t independently verified that, but, I know that they were they were looking at this, event because it was just there is such a, high magnitude of, snow accumulations.
00:12:00:13 – 00:12:29:17
Speaker 1
Yeah, that’ll be interesting to correlate with the observations that they were taking from the field project because they were taking, observations of these snow crystals as well. And, with those additional observations help help answer some important questions. How do we get electrification? Taking place here, under such cold, cold, conditions. So some interesting questions that will hopefully be answered from, from some of this.
00:12:29:17 – 00:12:33:17
Speaker 1
So, yeah. Thanks, Brian. Is there any other questions or comments on that?
00:12:33:19 – 00:12:46:19
Speaker 2
Yeah. Hey, Dan. Tony, did you check or maybe you wanted to. Scott can help. Was there ever a clear polar path to really pin down? Like ice?
00:12:46:22 – 00:12:48:21
Speaker 1
Yeah. Scott is going to discuss that and.
00:12:48:25 – 00:12:53:21
Speaker 2
Compare it, you know, between what cars are shown as well as what the model had.
00:12:53:29 – 00:12:56:03
Speaker 1
Yeah. Scott is going to, show that next.
00:12:56:05 – 00:12:58:12
Speaker 2
Oh, great. Okay.
00:12:58:15 – 00:13:10:00
Speaker 1
Okay. Well, at this point, I will turn it over to Scott. Lindstrom at, Simms in Wisconsin to talk about this a little bit more on some other topics as well.
00:13:10:02 – 00:13:44:23
Speaker 2
Thanks, Dan. I hope you can see my screen now. I’m showing a blog entry that was, there were super rapid scan, super rapid scan operation scans, during this event to support the ALS program. I was I’m just going to show you, if you, go to the Sam satellite bike, you can find this. I’m not going to try to show the one minute imagery over the, over the internet because, typically that doesn’t show up for a while, but it does show the structure that.
00:13:44:23 – 00:14:12:10
Speaker 2
Dan. Well, I’ll put it up here. It does show the structure that Dan mentioned, the three different bands, the elevated mixed layer and just some very nice detail to these images. And it’s really going to help underscore or help explain exactly what’s going on. During these outstanding lake effect, lake effect, lake effect, snow band events that occur with the big outbreaks of cold air.
00:14:12:12 – 00:14:39:02
Speaker 2
As far as lake ice goes, this is an image, that’s going to toggle through a different thing. This is showing some day night band imagery, from Sumi NPP, also on the same satellite blog. So here we have the up. Here we have it, it’s smaller scale. Let me just click on this. But if you again go to the same satellite like you can see this, and the day night band is showing this is a 660 image.
00:14:39:02 – 00:15:02:27
Speaker 2
642 Z. So the middle of the night. But it happened to be clear. So it shows a very nice representation of exactly where the lake ice is over Lake Erie. This is after the event. So this was after that lake event. Lake snow event. So is after there’s some more ice growth because of all the cold weather, but you can see 2 or 3 principal ice areas.
00:15:03:00 – 00:15:25:29
Speaker 2
One is, downstream just off of Sandusky and Cleveland. Then there’s another one, a little bit to the north of that. And then the eastern Lake Erie also looks to be clear of ice as well. One of the things you might ask yourself when you’re looking at this, I mean, are we looking at lake ice or is there cloudiness over the lake as well?
00:15:26:10 – 00:15:48:10
Speaker 2
And I’m gonna argue that this you’re looking at lake ice here, because there’s not really a signature in the, brightness temperature difference project. It’s also one of these. So we’re toggling between the day night band and then the brightness temperature difference between, the long wave in the shortwave air, which should highlight low clouds and nothing is really showing up.
00:15:48:10 – 00:16:14:02
Speaker 2
And then also the, the regular 11.45 micron thermal structure. So that’s the, the lake ice is a little bit cooler than the adjacent open waters. And again, there’s really nothing showing up. That suggests that there are clouds over this region. And another way you can look at this, on this particular day, there was a subsequent pass from Sumi NPP, about.
00:16:14:04 – 00:16:38:09
Speaker 2
So the next pass also went over lake here. Okay. Also viewed Lake Erie. And there wasn’t really much change in the in the features over the lake. So you expect clouds to move. Ice really doesn’t. So if you see some stationarity stationarity to the features, you can be a much more certain that you’re looking at ice on the lake and not, cloudiness.
00:16:38:09 – 00:17:01:06
Speaker 2
So the day night band at night, is just as useful as the visible imagery during the day, for identifying regions of lake ice. So this was just a nice example that happened, earlier this week. One other thing I want to talk about this is, getting over to a different coast. So we’re switching topics here.
00:17:01:15 – 00:17:30:12
Speaker 2
I’ve noticed lately, just how dry it’s been, on the West coast. So let me see if I can bring this up. So this is the, I was hoping this would, You can. I’m trying to get this into my, into the main window. So the the two small screens there that I hope are eventually going to, show up in the main screen once my Awacs catches up.
00:17:30:14 – 00:17:55:26
Speaker 2
Are the mimic off the west coast, showing just the extreme dryness of the West Coast. And the one on the bottom is the blended product percent of normal where that big dark region, off the west coast is values under 10% of normal. So just, let’s see what I can do here. Just some extreme dryness off the West Coast.
00:17:56:00 – 00:18:19:03
Speaker 2
I don’t think this is going to work for me right now. Being observed by the different methods of looking at total precipitable water. If you look at the drought, if you look at the drought Monitor. So this is the Drought Monitor that’s, coming out of the University of Nebraska. Again, it shows the extreme drought on the West Coast.
00:18:19:28 – 00:18:50:21
Speaker 2
Many stations in California for 2013 had less than 10% of their normal precipitation. So some extreme dryness. There’s also something called the evaporative stress index. This is more for the growing season, but this is showing you how. So there’s a website here. This is not in a WIPs quite yet, but this is showing you how, heat and winds, are helping to drive evapotranspiration.
00:18:50:21 – 00:19:10:09
Speaker 2
So it’s it’s kind of called the flash drought. It’s showing you short range changes in what’s going on in the boundary layer. So that’s all I have to talk about now there. So the extreme dryness on the West coast, a method for looking at the development of drought for the next growing season. You’ll notice the last image there is October 28th.
00:19:10:09 – 00:19:20:06
Speaker 2
That really starts up again in April. And does anyone have any questions on this?
00:19:20:08 – 00:19:56:22
Speaker 2
If not, I’m going to ask Dan to take this away and send it to, Scott Buck Meyer. Can I do that? I believe he passed it over to me. I’m not sure. Yeah, there it is. Okay. I’m sorry. So Scott talks about how dry it is in California. Yeah. So I thought I’d take a look at, high resolution, higher or higher resolution on our imagery to see if we can pick up any hot spots indicated any areas of active burning.
00:19:57:06 – 00:20:37:22
Speaker 2
And apparently at the time, there really isn’t anything huge going on in California, but I was able to find one little hot spot here, in this area, kind of on the, the, next week up in the mountains. But, as we’re getting to high, higher elevations, there is one hot spot here where you can see we do have an, an air temperature that’s a lot higher, and it has a a enhanced in here that it is a little bit hotter.
00:20:37:24 – 00:20:44:16
Speaker 2
Also, if I go out a little bit.
00:20:44:19 – 00:21:14:14
Speaker 2
I know this is kind of a bit of a lag here. And then we look at the, Ontario area of Kells for year. Sheet like this one and one more time. That’s about it. You can see there are a couple of black spots here I think that are you know again they’re a little bit hotter. So they are probably some small areas of burning.
00:21:14:24 – 00:21:54:03
Speaker 2
These could possibly be once we get into there’s just daytime heating and things dry out then and and the wind speeds increase. So we could see this small hot spots here, become a little. More active. And I believe they’re expecting Santa Anas today. So this will be something to watch. And so if we compare what we see with a one kilometer image from a year instrument or to my announcement panel.
00:21:54:06 – 00:22:52:27
Speaker 2
So here’s what it looks like. One kilometer, fares if we compare with, what it looks like from. Close at a resolution of four kilometers, you can see that there is indeed that hot spot, but it does not look as hot. And a few degrees of above what we have is a adjacent areas. But, you know, if it’s a small area in a small hotspot, you need to take a look at it with high resolution maps offered from the polar orbiters, for a minute, from instruments either, from the motors instruments or, levers and instruments.
00:22:53:23 – 00:23:03:12
Speaker 2
The only other thing I wanted to show is, there are some areas of for.
00:23:03:14 – 00:23:55:27
Speaker 2
Us. Images land take area. We get to this particular image here. And I guess here I was trying to toggle between, the fog stratus, which is just, an eye or a difference. And the daylight band, which again, since we have, what’s, is, You know, again, this can act as it’s invisible image at night, because there we can see, obviously, that, it is a fog area, but we guess.
00:23:55:29 – 00:24:00:23
Speaker 2
Still,
00:24:00:26 – 00:25:03:29
Speaker 2
See the edges? Pretty clearly because of the high spatial resolution and again, if we if we do a comparison. Of what we can see at one kilometer from various instruments as opposed to what we see on goes. You know, gets the overall edges just look right, are not as obvious. And so if you’re if it’s actually a color scheme that, you know, you, you’re if, if you’re, if, if you’re, if you have to have a look at this on a currently scale, it’ll be obvious to see what the actual actual edges are when you look at, higher spatial resolution.
00:25:04:13 – 00:25:19:20
Speaker 2
So we’re almost at the top of the hour. So I’ll go ahead and pause here and say if there are a means to ask, any comments or questions.
00:25:19:23 – 00:25:30:03
Speaker 2
Hey, Scott, you know, if, Mike, Pavel and I have started blending the, the two satellite sources.
00:25:30:06 – 00:25:58:05
Speaker 2
For the, I’m not really sure if he has, I had a real shot as an answer to that. Do you mean putting the Motus and the goes into one image? Yeah. Like somehow. Yeah. Combining them to be the best, you know, and to the best resolution. The picture. I’m not aware that it has been done now.
00:25:58:07 – 00:26:02:00
Speaker 2
Okay.
00:26:02:03 – 00:26:10:09
Speaker 1
Okay. Let’s turn it over to Ken Prior here. And Ken, maybe take about five minutes and then we’ll wrap up.
00:26:10:19 – 00:26:45:17
Speaker 2
Yeah. Sounds good. I will try to be as brief as possible here. So, if everybody see mine. Okay. To say. Yeah. Screen. Okay. Very good. So I’m going to switch over here, take a look at some satellite radar imagery. So what we’re talking what the hell? Mostly about winter weather. There was still some active convective storm activity, over the western Gulf of Mexico this past Monday morning.
00:26:45:27 – 00:27:26:13
Speaker 2
Even though there were no reports of severe winds up from the SPC storm report, a number of wind sensors on oil platforms in the northwestern Gulf of Mexico recorded winds, that met the criteria for, special marine warnings, which would be winds in excess of 34 knots. There were a couple of oil platform that recorded winds in excess of 35 knots in association with some, deeper convective storm activity, that occurred over the, north western Gulf of Mexico.
00:27:26:13 – 00:28:01:15
Speaker 2
This would have been between about, 1315 hundred day on Monday. The first oil platform to record high winds was the high island platform, which I’m pointing to. At this time, it’s a small white triangle here in the, more western, small white triangle. And if we take a look at the satellite imagery, this is the brightness temperature difference between the water vapor and infrared band, with those 13.
00:28:01:15 – 00:28:31:16
Speaker 2
So between bands three and four and I applied a cloud top pressure enhancement to show, some of the, coldest, cloud tops associated with the convective storm here, over, the northern Gulf, Mexico, south of the Louisiana coast. And then also to highlight the darker blue shading here over the western Gulf that indicate, large negative brightness temperature difference values.
00:28:31:16 – 00:29:09:06
Speaker 2
And these values have been found to correspond to very dry and tropospheric air. What I’m taking a look at here is how this dry tropospheric air interacted with the paper. Convective storm activity that extended from the southwestern. We’ve had a coast, southward into the western Gulf, Mexico, and the high island platform. Wind sensor here at 1330 and C on Monday recorded a wind gust of 42 knots associated with a deep convective storm.
00:29:09:06 – 00:29:51:09
Speaker 2
And I will go ahead now and overlay, composite reflectivity, radar imagery. This is from Lake Charles, Louisiana. Next Fred. And to show several bow echo segments here moving over the northwestern gulf. The high island platform was located in a region of developing or a cluster of developing convective storms at the south end of this, squall line complex, bow echo complex, and, very close to the time, the recording of down burst winds.
00:29:51:09 – 00:30:28:05
Speaker 2
We can see, one of these small, convective cells that was developing on the southern end of the, squall line. And this broke a segment that moved directly, over the, black form. And at this time, a wind sensor recorded a gust of 42 knots. What I’m most concerned about is the interaction of this dry air that we can see down to the west and southwest with the deeper convection, in this, bow echo complex.
00:30:28:16 – 00:31:01:17
Speaker 2
Taking a look at, like, first wind speed, potential index values, we can see that the, platform once located in a region with elevated MWP values, that were, in the upper teens, values, say between 15 and 20, core typically correlate to wind gust potential of 35 to 40 knots. And that’s, close to what we saw recorded, on the High island, oil platform.
00:31:01:19 – 00:31:38:18
Speaker 2
Taking a look at, skewed profile. And again, this is derived from the rapid refresh model analysis at 1300 C, we could also see what appears to be a shallow elevated mixed layer between the 550 and 700, Millibar, level layer here. And I believe that this elevated mix layer, provided some instability and particularly downdraft instability to result in these, stronger winds, over the Gulf of Mexico.
00:31:38:18 – 00:32:09:07
Speaker 2
So I will be looking, a lot more into this case, although, we did not meet severe criteria. Definitely. Winds up between 35 and 50 knots. Can and, provide a hazard or present hazard and, impacts to, marine transportation and, oil platforms over the Gulf of Mexico. So that is, pretty much all I have with this case at this time.
00:32:09:09 – 00:32:15:24
Speaker 2
Any questions?
00:32:15:27 – 00:32:44:15
Speaker 2
Hey, can just a clarification on the first image you showed with the radar? Yes. That’s the base reflectivity mosaic. Right. So this is composite reflectivity, long range composite reflectivity, meaning it’s the highest reflective of the, you know, the tilt of the radar scans. That is correct. That’s correct. The label said base reflectivity. Yeah, I yes, I do see that.
00:32:45:09 – 00:33:10:21
Speaker 2
However, I know that I ordered and downloaded to, composite reflectivity. This is from the NCDC next red archive. Okay. Reason because the city is labeling this as base reflectivity crop. That’s, correct. That should be composite reflectivity long range composite reflectivity. Okay. Thanks. No problem.
00:33:10:24 – 00:33:18:05
Speaker 1
Okay. Any other questions? From any of the presenters today?
00:33:18:08 – 00:33:22:05
Speaker 1
Okay. Well, thank you for participating in today’s visit. Satellite chat.