April 15, 2021 WY Conditions & Outlooks Presentation

Apr 21, 2021 17:25 · 5780 words · 28 minute read

Thank you, Windy. As Windy said, I’m Tony Bergantino. I’m the Acting Director of the Wyoming State Climate Office and Water Resources Data System. And I’d like to welcome you to our second Wyoming Conditions and Outlook presentation which is put together by my office, the U. S. Geological Survey, the National Weather Service and Missouri River Basin Forecast Center, University of Wyoming Extension and USDA Northern Plains Climate Hub, the Tribal Engineer’s Office of the Shoshone and Arapaho Tribes, and Natural Resources Conservation Service.

And, as Windy said, we’ll be looking at the past current climate conditions followed by the surface water situation. And we’ll hear about conditions on the Wind River Reservation. We’ll find out about forecasts and outlooks and then we’ll, we’ll wrap things with up up with how you can help us out. So, jumping into the current conditions… This is the US Drought Monitor map as of April 13th. This is a weekly product spanning through each Tuesday and this one was just released this morning.

Before I get into discussing the conditions, I’ll give my standard spiel on the makeup of the Drought Monitor. It’s based on many indicators such as, though not limited to, precipitation, soil moisture, stream flow, and things like that. The indicators are evaluated in terms of percentiles rather than as a percent of average which may be more familiar to you. A percentile differs from a percentage in that it is restricted between zero and a hundred so that’s your range of values with 50 being the median value or the one right in the middle.

Uh percentile ranking tells you where a value falls in relationship to the other, uh, observed values. So, if value were at the 20th percentile, that would mean that 20% of the values observed were lower than that value. Another way of looking at it is that the current value is lower than 80 percent of all the other values. So, say you were at the fifth percentile, that would mean you were in the lower, or, you were lower than 95 percent of all the observed values.

And if you were at the 50th percentile that is right about the middle, or the median, but that’s not necessarily the average. So up here in the upper right you can see the various percentiles that correspond to the various drought categories that are shown on the map over here. We had some good areas of improvement here in the last week or so we went over to… removed all drought up here in the north coming down into the Bighorn Basin we’ve improved things by about one category in this area here.

But, unfortunately, on the western side here we have, uh, two weeks in a row have degraded in quality. We’ve gone to filling in D0 and then in the map showing here just this morning we’ve, uh, added a bunch more of D1 over in here taking the place of some of the D0 that was sitting there. Uh, we’ve got a lot of extreme drought still sitting in the center portion of the state and down in south central areas as well.

03:09 - Alright, this is the 14-day total precipitation shown as a percentile. The Bighorn Basin here looking pretty good extending down into Fremont county a little bit over here in the eastern part of the state is above the median and then a little swath here along the high line is also above median. Unfortunately, we’ve got this area over here in the west which is well below the median down in below the 10th percentile in terms of precipitation which kind of corresponds to why some of that is degraded to D1 here in the last week.

And we also have some of this down here in in south central which shouldn’t be a surprise given the makeup of the Drought Monitor. And varying extents around the rest of the state here we have below the median as well. The gray area here is right about at the median. Taking a step back and going, uh, looking at a 90-day time frame we’re still seeing some of the results of that storm that we had in March are definitely influencing the map here, we’re seeing well above the median coming up through here north central and Fremont County, down into Sweetwater and even a little bit into Uinta.

But, again, even at 90 days, we’re seeing this, this dry area that’s persisting over here in the west. Up here in the northeast is still below median in terms of precipitation and that area down in south central just has persisted as well with below median precipitation received even, even over the last three months.

04:44 - This is the Standardized Precipitation Index showing for the state of Wyoming and in its simplest terms the SPI takes precipitation over a period of time and then calculates, it’s a statistical value, it calculates the number of standard deviations that that total is from the climatological normal for that period of time. So, the values center around zero with zero being about neutral conditions, uh, positive values which are shown here in the blue are wetter and then the yellows and reds are the negative values which are drier.

And, looking at the map here, at 30, 60, and 90 days, you can see in the north central area up here in the Bighorn Basin, uh, we’ve been consistently wet for a while and that corresponds with a little bit of improvement that we did do up here in the last week, like I say, removing the D0 that was over in this area here and then one category improvement down into about to the Washakie County line. And, at the same time, on the on the other side of the coin you see over here in the west consistently at least in the last 60 days we got some some good reds in there bad reds really, uh, in the negative and that’s, that’s also why that area is uh degraded here this morning in the map that came out going into you know the D1 that’s showing up here and up in here.

06:13 - This is looking at what our temperature has been over the last two weeks uh this is looking at the average minimum temperature over a 14-day period and nighttime lows throughout the whole state are still getting below freezing. Uh the red area here corresponds to just up to about 32 right about to the freezing mark so the whole state is still getting below freezing at night on average. However, if you look down here on the lower left we’re looking at the temperature departure from normal over that last 14 days and the west, southwest area a little bit over here in the southeastern plains has been below normal as far as temperature but this area here of yellowish and even sort of a darkish yellow orange color have been above average over that 14-day period.

07:05 - Looking at the maximum temperatures, uh, daytime highs all over the state are above freezing. Fairly cool still up at the very high elevations as one would expect, and quite warm out here on the, on the eastern plains getting up into the into the 60s as a maximum temperature averaged over the last 14 days. Looking down here again in the lower left corner, we’re seeing that we’re pretty much above average statewide except a little bit up in the Bighorns here and in the Winds.

Little bit of areas where we’re slightly below normal in, in terms of temperature. But the whole area here in the, in the yellow is zero to three degrees above average temperature and this area here in the southwest is in the range of three to six degrees above the average. So, definitely on the warmer side in terms of you know comparing it to normal statewide, really.

08:04 - Switching over to snow. This map on the left here shows our conditions two weeks ago roughly on the first of April. And then jumping forward to today we’re seeing on the, the left side here that we’ve declined in most of the basins, uh, in fact, it was much more of a decline and, in fact, all the basins had, uh, had dropped below what we were two weeks ago in terms of percent of median until we got the snows of this morning and, uh, yesterday that kind of brought things back up a little closer to where we were, but still not exceeding what we were two weeks ago.

The opposite ends of the state up in the northwest and the southeast are the only two basins that went, actually increased, in, in percent of median from last two weeks ago. And then the Tongue and the Bighorn Basin here stayed the same when you look at it compared to the first of April.

09:04 - This is very similar. This is also snowing, showing snow water equivalent but instead of looking at it as a basin number and basing it on the, the Snow Telemetry sites, this is using modeled values from a number of sources, CoCoRaHS, National Weather Service, just, just a myriad of sources that go into this and, again, if you would have looked at this two days ago it would have looked very similar to what we were on the first of April but, thanks to the snows of the last two days, we’ve seen improved lower elevation snowpack, so to speak, on the plains um south here, the central parts, and a little bit up into the Bighorn.

Unfortunately, the northeast has, has missed out on that, we’re not seeing anything, uh, you know, really up there improving, you know, what the snow, snowpack was on the plains there.

09:58 - Which moves us to the soil moisture which, you know, results from that snow melting, and the precipitation coming in and we have, we’ve gone downhill in almost all areas except for the Bighorn Basin up here. This is about the only area of the state that’s had any improvement in the soil moisture. As you can see from two weeks ago over here on the left, we had quite a bit of the area here it was in the 10th to 20th percentile, but when you look at soil moisture as of yesterday, actually, it’s all moved down into the 5 to 10 percentile, um, this is about the only area out here on the plains and the 10 to 20 that’s still remaining, uh, the area down here that was in the 20th to 30th has gone down about another 10 percentile.

And then, unfortunately, this, this whole big area down here in the south, south central part of the state has gotten a lot worse in terms of the percentile. We’re down, second percentile, I mean this is this is getting into a really dry soil conditions down in here. Which leads us to, I wanted to show you a little bit about what goes into that map and what one of the, a particular station would look like in terms of soil moisture at various depths. And when you look at a one station over time you can see the results of the storms that we’ve had here and, you know, in the last month and you can see as we’re coming along here this gray line here is at a depth of uh 10 centimeters below ground surface and the blue line here is at 20 centimeters.

And you can see right after that, uh, March, in the middle of March, March 12th, March 13th storm we had a fairly immediate response in terms of soil moisture starting to go up. Actually up fairly substantially, up to about 35 percent here at the, at the 20-centimeter level. And then a sort of a delayed reaction as that moisture worked its way down into the column about a week later at the 30- and the 40-centimeter depth we’re seeing it was a fairly quick reaction once, once it got to depth where on the red line here at 30 centimeters we jumped up to about 30 percent, uh, soil moisture content.

And then about a day or so delay from that and it didn’t work its way down to the 40-centimeter level and it took a little bit longer, it’s taken longer a slower reaction as we work our way up here you know a little bit starting getting into April we’re sort of peaking out here at about 25 percent. We don’t see that moisture really getting down to the half meter, 50 centimeter, uh, area here where there’s a little bit of a rise going up but it’s, you know, considering that we were at about 13%, we’re only up to about 15 percent from that.

And just threw this little one in here this was, uh, an extra little bit of boost of moisture that we got on the 6th of April. And only at the 10-centimeter depth can you see that, uh, start to rise up there about 5% and then it’s starting to taper off again. So this, this storm back here in early March really helped the soil moisture out. It’s starting to come down a little bit in the more shallow areas, uh, sort of holding our own at the 20-, 30-centimeter depth.

13:24 - And next up will be, uh, Aaron Fiaschetti with USGS to talk to us about surface water.

13:32 - Thank you Tony um here to just give an overview of the our gauging uh stations and flows in Wyoming um so as of right now if we take a look at the seven day averages throughout the state you’ll notice it a lot to appear to be near normal. We still have quite a few gauges that are in ice so they’re showing white um but hopefully that those as temperatures warm those gauges will come out of ice and we’ll start to be able to report values for those gauges.

14:10 - Notice that there’s a few areas that are showing below normal to much below normal and that’d be the Green in the north, Platte near Nebraska, and the Big Horn river up in the north.

14:26 - These uh this information comes from Waterwatch and it’s a really helpful tool but it’s always good to think about what you’re looking at here is that there’s a varying periods of record when they’re looking at comparing normals and in timing too so it’s not always comparing apples to apples. Um if we move on Tony uh the here’s a couple hydrographs from some of the drier areas and you can see up in the north on the Big Horn at Kane that had a little bit of bump in moisture coming off early but we’ve receded to be much below normal.

15:09 - Up to this date so in the we’ve seen the same thing when down in the south on the Green River near Green River is uh been much below normal a little bit of water came out from runoff but um still way below normal the next slide if we take a look now at the just a little bit longer average to the 28 day average we’re seeing a few more areas of dry especially over in the um in the south west corner that there’s a few more gauges that are showing periodic dry conditions when you look at the last 28 days and then there’s pretty good agreement with the Big Horn in the Platte continuing to stay dry and that you notice when we look at the 28 day average there’s a lot more stations are showing the white and the ice in the noticing that the so there’s less information there but the trends appear to be consistent with dry areas and areas that are showing normal conditions and I guess my biggest take-home message from this is that it’s really early for stream flow and when we’re looking at snowmelt uh dependent systems it will have a lot more information to know about a runoff and where we’re kind of falling as a below or above normal and certainly the effects of any recent precipitation or precipitation to occur in the future.

In the next slide Tony and just kind of taking an overview at reservoir storage throughout the state Brian presented this slide last month there’s really only been modest gains and in storage uh throughout the state in general one to two percent um that’s probably a result of not a lot of water moving through the system some of it could be management objectives but in general compared to this time last year storage volumes lag behind where they were.

17:31 - That’s that’s all I have. Next up uh Windy Kelley will be standing in for Brandon Reynolds to talk about conditions on the Wind River reservation. Thanks, Tony. So yes, Brandon Reynolds with the Office of Tribal Water Engineer put this slide together and asked me to present it today. So an update from the Wind River Reservation on conditions that they’re seeing the area has received some moisture in the last few weeks. So, they’re in a much better position than they were early in March; however, they’re still not out of the woods.

Brian or Brandon, excuse me, was in a meeting last night and he talked to one producer who said that in the last 24 hours he had received a good inch or so of moisture and he’s seeing it go into his field. So, they’re feeling a little bit better than they were early March, but again not out of the woods. You can see on his next bullet point that the moisture is going into the ground, not showing up as an increase in the stream or river flows – and that this most recent storm could change this though.

The stream flows are down due to the colder than normal temperatures, and also with that they’ve seen a decrease in the winds, which they’ve they’ve welcomed with that cooler temperature. So, the the Little Wind drainage, it’s a smaller drainage in their area in their area; however, there’s a lot of users of this drainage – and they still consider it a great concern, as in, in regard to drought. The Northern Arapaho and the Eastern Shoshone utilities pull water from the Little Wind, as well as many irrigators – so they’re really keeping an eye on it.

That being said, kind of more on the north and the south end of the Wind River Range, on the more eastern side, they are those areas are sitting a little bit better. So, they’re getting the the precipitation and they’re feeling better on the north and the south. Brandon did note that this year’s impact will be greater if they do not get the much-needed spring moisture, because of the conditions that they went into last fall. So, they had the, really as many of us, the really dry summer 2020, they did not get the precipitation in the fall or really in the winter – they didn’t see precipitation until March.

So, unless conditions change sooner, rather than later, they do have some some great concerns of what the summer will bring. And regardless, they do have some concerns about the feed or hay production and what it will be this coming growing season. Brandon wanted to share that the market forces, along with weather, are still impacting the local producers – including the price of diesel, feed, cattle prices, etc. And he just wanted to re-emphasize that they’re really grateful for the recent moisture and lower temperatures, but he wanted to remind individuals who might be watching this later that they’re still not out of the woods.

So, to be planning for the different situations that could develop this coming summer, because the critical period will be the next two months – whether the drought worsens or if conditions will improve.

21:07 - Thank you Windy. Next up is Aviva Braun with National Weather Service in Cheyenne to talk about forecasts and outlooks. Good afternoon everyone. Um, so let me get right into our forecast. Um, this is the seven day quantitative precipitation forecast which basically is the liquid precipitation; so this can fall as rain, snow, graupel, whatever it is, but this is the liquid totals; and I think everybody’s noted that we’re in an active period with a number of systems moving through the state, so we do have quite a bit of precipitation forecasts across the state and the areas that are doing the best are of course the mountains: big horn mountains to the north, down to the medicine bow mountains to the south, and further east of that area.

The section of the state that will do a little less well is of course the southwest corner. So, we’re seeing this widespread snow today; it’ll continue on through Saturday, and then we’ll have a little bit of a break before we get another cold front with some more snow likely Sunday into Monday.

22:20 - Getting a look at what’s to come: this is our probability of precipitation and temperature. In the top right corner is our probability for our, for our precipitation amounts. And so basically probability means it’s our chance of getting something. So our chance of below normal precipitation is favored for the state of Wyoming in the next six to ten day period. In the bottom left corner, we’re going over to temperature and again this is our chance of receiving temperatures, and we are below normal for our colder temperatures.

So across the state we’re looking at colder, so the overall picture for six a day, six to ten day period is colder and drier.

23:17 - For the eight to fourteen day period, again, this is our probability or chance of occurrence. In the top right corner, we’re looking at slightly below normal precipitation favored again for the whole state, and then in the bottom right corner, our temperature forecast: we’re actually sitting at our equal chances of of either near normal temperatures favored across the state. We do have um some sections to the far east that have a little bit of a cold chance and warmer chances towards the southwest, but overall equal chances for the state of um those types of temperatures so the 8 to 14 day period equal chances of being warm or cold but we are going to be drier.

24:10 - So I think, I hope, that everybody was noticing that underlying theme of drier over the next couple of weeks, even though we are in a wetter period right now. Um, so this is the ENSO forecast. ENSO stands for El Nino Southern Oscillation, and we just should note here that Wyoming’s weather is not as strongly correlated to ENSO due to our distance from the ocean, however, it does provide us a signal of what is to come or what we can look forward to. Um and so, that first area that is circled um on the left side of the graphic, um we are coming out of a La Nina pattern into neutral; that gray is neutral.

Uh, a neutral forecast for ENO and so there is a possibility for more precipitation, but did put a question mark there because it’s neutral and so it could go either direction as we’re seeing due to many other signals that are looked at. Um that it doesn’t necessarily mean that we’re going to be getting the precipitation that we we were hoping for. That section on the right side of the graphic that is circled; that’s getting into the next summer into fall portion of the area of the calendar.

So, that’s September, October, November, October, November, December, and into January; and we’re seeing those blues starting to pop out again. And that blue is our La Nina being favored once more, and if La Nina’s favored again, we could be looking at another period of dry in the long term.

26:01 - the next summer into fall portion of the area of the calendar so that’s september october november october november december and into january and we’re seeing those blues starting to pop out again and that blue is our la nina being favored once more and if la nina’s favored again we could be looking at another period of dry in the long term So again, um, the underlying theme and the correlation to ENSO - of course we look at plenty of other signals, but all this is starting to indicate um a long-term drought possibility.

So our graphic on the left side of the screen, that’s our seasonal drought outlook. It is valid between now through the end of July and it’s showing that we are going to be seeing persistent drought, or development of drought, likely across the state of Wyoming. And this can be correlated then to our wildland fire outlook, and we’re seeing that on the right side of the screen, and that red area then signals a greater greater chance of significant wildfires occurring across the southwest portion of the state.

So I just want to say here that it’s significant wildland fire, so these are our large wildland fires, not necessarily any wildland fires that we could see. And of course, July is just the beginning of fire season for our state. Many of our larger fires have of course occurred in towards the end of the summer and into the fall.

27:29 - Now coming back to the current period. Um, SNOTEL, these are our SNOTEL sites um and the amount of snow that we’re seeing in these areas. SNOTEL sites is our snow telemetry. I always mispronounce this word, sorry, telemetry; um they are maintained by NRCS and they are monitoring stations measuring the snowpack, the precipitation, the temperature, and other climate conditions across our mountains for the state of Wyoming. And the top graphic is for the Windy Peak site in the North Laramie Mountains, and this um indicates that there are pockets of near to above normal snow totals in the North Laramie Range.

The Bighorn Mountains and the Sierra Madre Range, then going towards the bottom graphic, this is in the Wind River Range; it’s for the St Lawrence site, and we are seeing many areas where we’re seeing much lower snow amounts and this is in the Wind River Range, the Wyoming Range, and other high terrain areas in the northwest showing well below normal snow amounts for this time of year. Those green lines in the center of each of these graphics show the mean average snow amounts per any time of the year, and you’ll see that we’re close towards, getting close to the end of when we normally see additional snow being added to our snowpack; and in about a week we’re going to start seeing a drop of snow totals across the state.

So we’ve got another week to try to add to what we’ve got, and this next week will give us some good chances, and then we’ll start seeing the average decrease.

29:31 - I’m going to be turning this on over to Kevin Low.

29:37 - Alright, thank you very much. My name is Kevin Low. I’m also with the National Weather Service. I’m with the River Forecast Center that’s located in Kansas City, and so given the conditions that the first three presenters have given soil conditions and snow conditions there’s very little chance of flooding across the state over the next three months. The graphic that you see there, uh the, the dots are the locations uh that the National Weather Service actually uh will issue a river forecast for and uh green means that it has a 50 percent or less chance of getting to flood stage.

And so most of these are well below 50 percent uh likelihood of going to floods. So again, the primary driver is the low mountain snows as well as the extreme dry soil conditions. You can go to the National Weather Service issued its US spring outlook, which covers flood potential across the United States in that lower left or no lower right link and in the lower uh left link you can get to a national map. I obtained this graphic from and so you can look – each month and see the updated flood potential outlook, so again there’s very little chance that we’ll see flooding anywhere in the state of Wyoming this, uh, snowmelt season.

Thank you. Thanks, Kevin. And Windy Kelley with the, uh, with the USDA Northern Plains Climate Hub and UW Extension will wrap us up with how we can get involved. Great thank you, Tony. So, before I talk about how we can all get involved in providing condition updates and reports, I just want to recap the US Drought Monitor map, that was released this morning – that Tony kicked us off with. So again, in the green circle, in the upper north central part of Wyoming we’ve seen an improvement here with increased moisture, which has been great to see throughout that area.

That being said, along the western side, you see in the red circle, we have seen an increased deficit in moisture, and so, the, this week we did see an increase in severity on the US Drought Monitor map. So, on the next slide I want to share just a couple of ways that you can get involved in helping us understand the conditions out on the ground – which we, we use that information to inform our recommendations to the US Drought Monitor, so in other words, the next couple of slides I’m going to share on how you can get involved or ways that you can help raise the flag, so to speak, if there’s an issue out on the ground or conditions are improving.

And it helps us to cross check the instrumentation that we use or the data that we’re reviewing on a weekly basis to make recommendations to us to the US Drought Monitor, as well as to provide that information to other entities that we need to provide it to. So, if you’re not familiar with the CoCoRaHS program, this is a citizen science program – it’s where you have the opportunity to monitor precipitation, or lack of, on a daily basis or as often as you can you can report it – as easily through your phone, if you have a smartphone there’s an app where you can log into – a website database.

On the right-hand side of the screen, you can see all the Wyoming active station locations, so these are where people have or volunteers now whether or not they actually report is another story – or the frequency. So, the more reports we can get out on the ground the better and that’s what you can see on the left hand side of the screen, I pulled this map this morning April 15th, and these are the reports as of about 7 a. m So, you can see that there’s a lot of gaps out throughout the world throughout the state.

And we know how variable precipitation is, so the more individuals that can report the better off and the more data we can have. Another opportunity that is out there is called Condition Monitoring Observer Reports or CMOR. This is a national database where you can report conditions from severely dry all the way to severely wet. So, it’s all conditions. You can see the bitly link on the screen – as well as for Wyoming I looked again this morning, we’ve received two reports in the system for the calendar year, so far – and they are back at the end of January and the beginning of February.

I do like to recommend that folks, similar to other types of monitoring, consider marking your calendar for, for example, the first of the month or the 15th and submitting a report into the system – just so that myself and others, including Drought Monitor authors have a log or documentation of what conditions are like in the area that you’re at, and then we can compare it from one year to another. Particularly being able to compare photos Tony. So again, regardless of the conditions, consider submitting a report and I want to emphasize the opportunity to submit comparison photos to the CMOR system.

We all know that a picture speaks a thousand words. And last summer, I did receive a lot of photos, but it would be a singular photo of a past year at that point of time in an area of Wyoming I don’t know, and I don’t know that pasture. So, it wasn’t as helpful, even though I did appreciate the effort. And so whether, if you’re emailing me pictures or Tony or submitting them to the CMOR system, we ask that you do provide a comparison photo showing what that pasture looks like in a more average year or more wet year to that point in time – and try to have it taken around the same point of time.

So, if it’s July 15th of this year, having a picture from a more normal year, from July 15th. The other thing I wanted to note with the CMOR system is that it doesn’t always play friends friendly with all web browsers. So, if you’re having issues, I encourage you to try a different web browser to see if that helps with submitting your report. So, with that I would like to thank all of the partners putting the webinar together today. It includes the USDA Northern Plains Climate Hub, the National Weather Service, USGS, the Water Resources Data System or WRDS, the State Climate Office, the Office of Tribal Water Engineers, and the University of Wyoming Extension.

And you can see on the screen here the names of all the presenters as well as their email address – in case you would like to reach out to them after today’s presentation. Thank you. .