March 18, 2021 WY Conditions & Outlooks Presentation

Mar 24, 2021 15:09 · 5967 words · 29 minute read

I’m Tony Bergantino. I’m the acting director of the Wyoming State Climate Office and the Water Resources Data System. And I’d also like to welcome you to our Wyoming Conditions and Outlooks presentation, which is brought to you by my office State Climate Office, the National Weather Service in the Missouri River Basin Forecast Center, the University of Wyoming Extension and USDA Northern Plains Climate Hub, the Tribal Engineers Office of the Shoshone and Arapaho tribes, the US Geological Survey, and the Natural Resources Conservation Service.

So let’s get started, in here with what our current conditions are and this is the current US Drought Monitor map as of March 16th. This is created weekly and was just released this morning. I had some large areas of improvement this weekend and for the since the previous one down in the southeast here and a little bit over here in the in the western part of the state – with areas receiving one to two inches of liquid precipitation here in the east and in the west – there some of the precipitation indexes at 120 days were getting normal to wet.

And that was the same in the eastern part of the state as well even prior to the storm. So, there were some areas here that were ripe for improvement even before the storm, but when we got that dumping of snow, we did get a much larger area that was improved one category in the in the Drought Monitor. We do still have some extreme drought here – in the central part of the state and down here in the south center part of the state, that has been lingering for quite a while.

But before I get too far into this, a little bit of a word about the makeup of the Drought Monitor. It’s based on various indicators such as, but not limited to, precipitation soil moisture, stream flow – things of that nature. The indicators are evaluated in terms of a percentile rather than as a percent of average, and the percentile varies from a percentage in that it is restricted between 0 and 100 with 50 being the median value. So, percentile ranking tells you where a value falls, you know relative to all the other observed values.

So, if you had a value that was at the 20th percentile that would mean that 20 percent of values observed were lower than that value or another way of looking at it is that 80 of the values are are greater than that value. So, if you’re at the fifth percentile that would mean that ninety percent of the uh observed values were greater than that. And if you’re at the 50th percentile it means you’re right about the middle, which is not necessarily the average, but it’s the middle of what has been observed in the in the past.

And here you can see the percentiles that are used to come up with the various categories that are are depicted on the map – uh just just a listing here going up from the worst category of D4, exceptional drought, up to what we call abnormally dry, and then anything above that there’s there’s no condition associated with it.

03:01 - Now this is the 14-day total precipitation across the state, as a percentile. You can see the areas here, above the median – all across central, southeast down here in the southwest, and then below median are these areas over here in the Lincoln, Sublette, Teton, Park, Bighorn Basin, and then up here in the northeast, which received less than the median and precipitation. And this is the same map looking back at 90 days total precipitation. And again, the areas above northcentral central, down here in the southwest, a bit east central area, and in the southeast – and same areas of concern really.

Wind River Range up here in the northwest and again the northeast has not received the benefit of the snows that we got here in the last week so. It’s it’s still not looking good even at 90 days.

04:03 - This is the standardized precipitation index. And what this is, is it takes precipitation total over a period of time. In this case we have the 30, the 60, and the 90 that we’re showing here, and then it calculates the number of standard deviations that the total is from the average precipitation for that period. And with that, the values center around zero with positive values being wet, and shown here in blue, and negative values being the dry ones that you see in the yellows and the reds.

And as you can see here, we have some emerging areas in western Wyoming where we’re we’re in the negative portion. Up here in the Bighorn Basin, which hasn’t been too bad, uh you know looking back 60 and 90 days, but in the 30 day it’s starting to emerge as dry. And then in the northeast, here uh going back to the 90 days, we’re seeing uh at in some places and now in the 30 day it’s it’s well below the the zero range.

05:06 - Now this is the 14-day average minimum temperature, uh over here, on the upper upper right, this shows the uh the nighttime lows are still getting below freezing. Uh some of these areas here, are getting fairly close to being above freezing all day, but not quite there yet. The northwest, here, is well below freezing at night. Down here on the lower left, we have the departure of that temperature over the 14 days the departure from the average.

And you can see up here again, the northeast has been above average, the northwest is a bit below the average, and most of the state is although above average. It’s only, you know, zero to three degrees above with a few pockets here that are below the median.

05:56 - And this is showing us the 14-day maximum temperature. And here you can see that with the exception of the high elevations, and the Wind and the Bighorn, a little bit up and hearing that the daytime temperatures pretty much across the entire state are getting above freezing. So, we’re getting sort of a cycle of melt, freeze, melt as the days go by. Down here, on the lower left, we have the again, the 14-day maximum temperature, but this time shown again as the departure from normal.

And again, you have the the northeast here above the average, the northwest here is also above the average. Quite a large junction uh here of the, you know the eastern plains, Fremont County, down here in the Sweetwater are below average – with the rest of the state being about zero to three degrees above the average.

06:50 - This is the basin wide snowpack. This is based on the the NRCS snow telemetry sites, so this is the high elevation stations. And this compares last week over or two weeks ago over here on the left to what we are here on the right – after the storm we had this last weekend. And you can see quite a bit of improvement here in the east. In fact, everything to the east of this red line, red and squiggly line, went up – with the exception of the the Tongue, up here, stayed about the same.

It has declined a little bit it had gone up above what it had been two weeks ago, and then it’s come down the western part of the state over here behind the behind the red line has decreased, unfortunately. But, the snow, was a as I said, was a great benefit to the the eastern two-thirds uh three quarters plus of the state.

07:47 - This is also snow water equivalent, but this is the modeled snow water equivalent. So, while the previous slide was taken from actual, of the high elevation snow telemetry sites, this is modeled from multiple readings. CoCoRaHS observations, Weather Service observations all around, and again here’s a comparison from two weeks ago, over here on the left, where most of the plains – up into the into Fremont County are the Bighorns was way way down – in you know, less than the 10th percentile, as far as as snowpack.

And then we had the storm this weekend, and low and behold, quite a bit of improvement. Again, Bighorn Basin unfortunately, and you saw that in the previous slide, where we had this area of concern up here and this is part of why, because it missed out on the snows that we saw this weekend. And so the snow water equivalent down at the lower elevations is is a lot more depleted than you know the rest of the state over here. Looking at the especially the eastern plains where we got the part of the major dumping and even the area along here, on the i-80 corridor, picked up quite a bit as you saw with the fun they had shoveling all that and plowing that all out.

Now what has this done in terms of soil moisture? That’s a good question. It has really improved things over here in the east, uh, this has gone from down into the second to fifth uh percentile all the way up to 10 to 20th. It’s still dry, but we’re seeing the moisture from that snow starting to melt. And it’s actually going into the soil column, which is uh we’re still a long ways from saying, “hey things are are great,” but it’s a major improvement from where we were at, uh, you know two weeks ago – when you see southern half of the state was uh down under the fifth percentile, and then even up here into the northeast we were up into the you know, under the 10th percentile.

But what we’re seeing here is, the northeast here is still in a pretty critical area, as far as the amount of moisture in the soil. Uh, same over here in the western portion state. It’s getting worse as well. And also coming down into here, where we were you know above the 40th percentile two weeks ago, 30th sort of in here, now it’s uh under the 20th for this entire scoop here. And these areas here, again, correspond to those areas that we were seeing in that standardized precipitation index of areas of concern.

So, with that I will turn it over to Brian Loving with the USGS who will talk about where we are at with surface water.

10:26 - Yeah. Hi, good afternoon everybody. I want to talk a little bit about the streamflow conditions around the state. One of the first things I want to point out is that due to the nature of the way that we measure stream flow, if there is ice in the stream, we’re not able to report discharge. So, this is a map of all the stations where USGS monitors stream flow across the state. And the circles that are gray or white are sites where, right now, we still have ice conditions, so we are not able to report the flows.

So, for the most part, this time of year and certainly you know the past few months when we have iced up stations uh a lot of a lot of the graphs and charts that I’m going to show aren’t that meaningful yet – because they’re based on such a small amount of data. So anyhow, you can see you know the colors is similar to a lot of the maps that Tony just showed for other parameters – but cool colors, blues and greens, indicate that we’re at or above normal flows in the streams, and then warmer colors, browns, oranges, reds indicate we’re below normal.

So, you can see it’s kind of mixed right now. There’s not any definite pattern and part of that’s just because of the low flow conditions. We’ll have a better idea in a month or two what’s really going on in the state.

11:43 - Okay, so this this is a similar map to the one we just saw. But here we kind of um take those data points and make some estimation about what’s going on across the entire basin. So, you can see for the most part we have normal conditions, maybe slightly below normal – overall across the state. But there are also basins that are slightly above normal. Again, based on a small number of data points. You can see that um there are three basins where we don’t have any data right now: the Powder Basin, all of the gauges are still frozen up; the Little Missouri Basin, just east of their gauges within the state or even within Montana in that river basin; and then yeah, a Great Divide Basin, and we don’t have any monitoring down there.

So, Great Divide and Little Missouri always show up as white year-round. But again, as in a month or so from now, next month when we meet, we’ll probably have some much more meaningful information this map and be based on a lot more data.

12:43 - And then a third graph I show, that’s based on that same data you just saw. This kind of shows an average stream flow for the state. You know kind of composite of all the different stations we have out there across the basins and shows you the flow right now at the stations that where we are reporting data – compared to the long-term trends, uh for this certain time of year. So, obviously in the wintertime is when the flows are always the lowest, and in the summer is when the flows are the highest.

You can see that black trend line, where the red dot is on it right now. We’re starting to actually move into, with the stations that are reporting again, it’s a small number right, now but we’re starting to move into below normal conditions. Tony explained percentiles, and we’re in the 10 to 20 – around 10 to 25th percentile in flows right now. Um actually, we’re probably around the 25th percentile, kind of that area. But the trend isn’t good right now, and hopefully, um hopefully things will will get wetter.

And again, as we get more sites online the ice moves out, we’ll have a better picture of what’s going on. And I have one last slide for you. This is looking at the reservoir. This is a product from Tony’s office. We’ve got all the reservoirs around the state and you kind of get a condition of how the percentage full they are based on the amount of blue that fills up in the little rectangle. So really, I’ve got the big map on the left shows the current conditions or the conditions as of yesterday, and then on the right we have the conditions from a year ago.

And really, the conditions are pretty similar between the two years – maybe we have slightly less water stored this year at this time, than we did a year ago. The most notable reservoirs, that are they’re, a little lower are Seminoe, Pathfinder, Palisades, Big Sandy, and Woodruff Narrows. And then, also, the the larger Colorado River Basin lakes downstream – Lake Powell, Lake Mead. They’re also, uh, significantly lower – well uh, volume wise they’re quite a bit lower than last year, compared to what we have in our reservoir.

So, reservoir conditions are down a little bit, and stream flows are kind of the same story. So, as far as stream flow goes, uh that’s that’s all we have right now. Thank you. Next, uh, Brandon Reynolds will talk to us about conditions on the Wind River Reservation. Yep, thanks Tony. Um, yeah, so again, I’m not the quantitative guy, but just have been speaking with some of the producers here on the Reservation. And, um, as Tony alluded to, we picked up some pretty good moisture, um, really good moisture compared to anything we’ve had recently.

So, you know doing pretty good for the near-term. I talked to one producer last night. And he said we’ve had two rounds of snow here on the reservation, we didn’t just get one big slug like a lot of the state did recently. Um but, after the first snow, he was out plowing, um, for calves and hay, and he said the ground was still really dry underneath, after that first snow – but, after this more recent storm, um, it was real, you know, wet and mucky to depth.

So, like Tony said, that soil moisture is finally starting to get in there, which is good. The foothills, in the mountains, received pretty significant snow on the Reservation, but really good to see it out in the basin — the fields and ditches, and the range definitely needed the moisture. And not just when snow melt came off later this year. So, definitely doing better than we were. We’re at about average, uh, for the SNOTELS on the Wind River reservation – um, that’s not all the Wind River Basin, but that’s where we’re at.

Um we talked; we had our water board meeting yesterday. But about this time last year, we were at 113 of average, um, for the Wind River Reservation and we ended up in a severe drought. So, we’re definitely not out of the woods yet, but we’ll take every little bit we can get. So, things are looking a lot better than last week and earlier this winter. So, the other thing I’ve talked to the producers around here about, oh sorry Tony, is the hay prices are still really high – so, this moisture helps in the near term, but it didn’t change a lot of the problems we saw coming out of the drought last year.

So, hay prices are high, you know range isn’t good – this moisture helps, but definitely not out of the woods yet. The other thing we’ve seen is not a real significant uptick in runoff. A lot of this water has went into the ground and isn’t making it to the streams, but um you know that’s good. So like I said, just happy to see the snow and we’ll keep going, and then you know – guardedly optimistic for more moisture in the next couple of weeks. So um, going back to the stream flows, I’ll talk about the photo here in a second, but we had an update from the Bureau of Reclamation, um, yesterday at the water board meeting.

And, they gave us the March first stream flow predicted runoff from April to July on the Wind River system. So, Boysen they’re looking at a 64-average inflow into Boysen this year, 83 percent average inflow in the Bull Lake, and about 69 into the Wind River system. Um, so you know, 72 average is it’s good, but it’s you know it’s not enough. So, but that really bumped up, we were at 61 at the beginning of February, so definitely ticking up here. Um and then, the NRCS actually flew into the Hobbs Park SNOTEL, um, this is March 4th, but this is the conditions at 10,100 feet.

You know two weeks ago you can see that meadow, where they landed, you know at 10,000 feet it shouldn’t be bare ground, uh, on March 4th – so and then, you can see the mountains above there, you know not real big drifts or anything like that. So, that’s what we were staring the face of before this most recent round of moisture – so you know, good moisture, but definitely not out of the woods yet. And um you know just, this was our reality until this most recent round, so things are looking better, but uh, yeah not not out of the woods at all – a lot of the season to go yet.

So, thanks Tony whoever’s next. All right, next is Jared Allen with the National Weather Service in Cheyenne to talk about forecasts and outlooks. Great, thanks Tony, appreciate it. If you don’t mind going one slide forward, there. Uh so, we’re looking at the seven-day quantitative precipitation forecast for March 18th through the 25th. So, quantitative precipitation forecast that’s kind of a mouthful, but essentially that just means the liquid precipitation forecast, since we’re still talking about a vast majority of the precipitation coming down being snowfall.

But, essentially it’s the snow water equivalent, or how much water is in that snow that will that that could melt out. So, some decent amounts, of course, across the higher terrain of the Bighorns, the Wind River Range, and the the Wyoming ranges. Uh, there in the northwest, uh, there from Park County southward through Lincoln County, and then also the mountain ranges in the southeast – for the Sierra Madre, Snowys, and a little bit of the the southern Laramie Mountain Range, as well, look to pick up the most over the next seven days – and even some of the lower terrain in the east high plains could also pick up some upwards of a tenth of an inch to quarter of an inch.

Maybe, if we get lucky, a half inch in some of those, uh, locations as well. So, the main time frame, for all of this, is where we’re looking quite dry and nice a nice short warm-up right now – across the state for today tomorrow, and into sun into Saturday. And then, late Saturday night into Sunday, we’re going to see another Pacific cold front, Pacific system come through, across the region. And then, bring initially rain to some of the high plains and then it’s going to be a rain-snow mix through the night Saturday, and then turn eventually to all snow on Sunday across the state.

And then, this system will kind of linger around the area through Monday, and maybe even into Tuesday morning. So, essentially late Saturday night through Tuesday that’s going to be the main precipitation episode for this upcoming week. And if you want to transition to the next slide, please. So, looking a little bit beyond this period – six to ten days precipitation across the state, we’re kind of bifurcated there. So, the southeast is a little bit favored to be above normal.

A very small sliver there in the southeast part of the state, but a vast majority of the state’s going to be equal chances. Essentially where there’s not a really strong signal for above or below average chances, but then there towards the west – the further west you go, a slight signal for less than normal chances. And then in for the 60-day temperature outlook, there looks to be a large weather system and large troughing across the uh western half of the United States.

And that’s generally going to bring some colder air from the Pacific Northwest. It’s not going to be true Canadian cold air, but just some colder air kind of from the Pacific Northwest Pacific. So slightly below normal temperatures are favored across the state through the next 10, for the period of 10 6 to 10 days – March 23rd through the 27th. And going forward, a little bit more, for the 8 to 14-day unfortunately we kind of see that precipitation outlook drier than normal precipitation being favored expand across the state.

So unfortunately, even after this nice round of precipitation that we had this past weekend, and maybe this upcoming weekend, we might be in a more drier pattern going into the extended period. And then, for the 8 to 14-day temperature outlook continued on the cool side across the majority of the state with below temperatures favored for our area. And then going forward, one more on the next slide, this is a large-scale outlook of where we’re going to be anticipating the reduction of La Nina conditions.

So, you can see that really tall blue bar that’s ongoing right now, for February, March, April of the probability for La Nina conditions. But then you can see how that probability really reduces going into the later spring and then summer months where we go more to a neutral pattern – but then far beyond there is some climatological modeling that kind of indicates where La Nina conditions could potentially return late fall and into next winter. So, we’ll have to monitor this of course, but that could spell a potential for a drier longer term, uh, where we kind of are in this longer-term drought aspect at the moment.

We might get some very short reprieves, you know just like from the system that we just had, and that’s not to say that we won’t have some additional spring snow systems as well uh – that will help temporarily. But overall and unfortunately, it looks like the longer-term average looks to have below normal precipitation chances and some type of drought persisting. And if you want to go one more forward Tony. Thank you, sir. Just for around here, just wanted to highlight some of the SNOTEL sites.

SNOTEL, just stand like Tony said, stands for snow telemetry, which are monitoring stations that measure snowpack, precipitation, temperature, and other climate conditions. So just highlighting the north Laramie Mountains, this is Windy Peak, and just want to really highlight where we were right before this snow system and where we are now. We were pretty much riding in the the 15th to 20th percentile for overall snow amounts down there – kind of in that yellow red region, and then all of a sudden we just climbed a huge mountain there, and are now almost sitting, uh, well above the median and near the the all-time maxs for for this period of record for the north Laramie Mountains in this range.

So that right there is a snow water equivalent jump of about four to five almost six inches uh just based off this one storm that we had where they picked up over 50 inches at this one site over this past weekend. But also draw your attention down there towards the Wind River Range that was so well highlighted, uh, by the the previous gentleman where they had seen very little snow up there across the Wind River Range up there at that 10,000-foot level.

From that picture and you can see it was just setting and has been setting minimum records throughout the entire winter. So luckily, they did get that little bump that you can see right there, but they’re still sitting near minimum period of record numbers. So in some cases we’ll have to kind of monitor for some higher flows coming from some of this uh water in some locations, uh but still there are certain point locations that are are still hurting significantly from the the lack of snowfall and snow water equivalents.

And if you want to go one more Tony. I will then turn it over to Kevin Low who’s at the Mississippi, excuse me, the Missouri River Forecast Center.

25:25 - All righty, thank you. Yes. So I’m Kevin – I’m with the River Forecast Center located in Kansas City. Uh so the, what you’re seeing here is a graphic of the state of Wyoming. Our office covers the eastern portion, the office in Portland, Oregon covers the northwest, and the office in Salt Lake covers the southeast, but we’re all telling about the same story. Um, due to the lack of moisture, that everyone’s been talking about up to this point, even with the with the recent, uh, storm that hit the eastern side, um, we still don’t have any sort of flood risk over the next three months.

So, what this graphic shows is the, uh, what we call long range stage outlook, uh, for the oh, about 40 or so locations at the National Weather Service issues river forecasts for. So, all of them are green – meaning that over the next, uh, three months through mid – let’s see, you know what – that is uh, mid-March through, it should say through, uh, mid-June. I apologize for that. But, um, uh, through the mid-June we’re not showing really any any chance for flooding at any of these sites.

Like the NRCS, we also do a a water supply forecast as well, and as been mentioned earlier, we are also, our numbers are also showing well below normal for the April through September volumes. So, I will add that the links that I’m showing at the bottom, uh, the long-range river outlooks, if you, if once you get the slide deck you can click on that and that’ll take you to a place that you can see the entire nation as far as what the 90-day outlooks are.

The link on the lower right is actually out of date, because that was just the announcement that the National Weather Service would be issuing at spring outlook today, which it did at 11 o’clock eastern time this morning. So, I did put in the chat the link for the, uh, NOAA’s 2021 spring outlook – and you can look at that for the entire nation as far as what the flood risk is. So, with that I will turn it to the next speaker. Thank you. And now we’ll have Windy Kelley with the USDA Northern Plains Climate Hub and UW Extension to talk about reporting conditions and wrapping us up.

Great. Thank you, Tony, and thanks Kevin for transitioning. Um, Tony, you can go ahead and switch to the next slide. So, I just wanted to recap the US Drought Monitor map that was released today, and that Tony kicked us off with – giving us an update on the improvements that we’ve seen in the state. Specifically in east central as well as southeast Wyoming, with that heavy snow event that we had and then the long-term precipitation percentiles over there in the western part of the state – and Lincoln County into western Sweetwater County as well.

So, we have had some improvements, which is great, and but, we still see an awful lot of extreme drought in areas of Wyoming – as well as severe drought and moderate drought. Tony, go ahead and switch. So, keeping this in mind, we’ve talked about, and we’ve seen through the conditions that there’s a lot of variability in precipitation, and where it falls. And one of the tools that we do use or that is used to help us know where precipitation is falling, or not, is CoCoRaHS.

If you’re not familiar with it, it’s a citizen science program that you can volunteer to monitor precipitation and report it on an, ideally, on a daily basis. So, the map on the right-hand side of the screen are the active stations, here in Wyoming. These are people that are volunteering and recording precipitation, ideally again, on a daily basis about 7 a. m. And the map on the left-side of the screen, is the map from this morning. So, you can get an idea that the little gray dots were recordings of zero precipitation, and then there was some traces there in Laramie County as well Sweetwater County, Sublette had a little bit of moisture that was reported, as well this morning.

But there’s also a lot of areas that haven’t been filled in. So, if you’re not a CoCoRaHS volunteer, I do encourage you to consider volunteering – that’s really easy. I have a phone app that I can record the precipitation, that was, that fell, or did not fall, on a daily basis right into my phone. And Tony Bergantino, that is with us today, he is the the lead of the CoCoRaHS program here for Wyoming. So, you can reach out to Tony directly, or you can reach out to myself, as well, and we can help connect you, and get you a standard rain gauge for this.

Another opportunity to help us understand the conditions out on the ground is, next slide please, is through the Condition Monitoring Observer Report System. This is a national database where you can go in and report conditions from severely dry to near normal, all the way to severely wet. So it’s the whole spectrum, and it includes reporting impacts and conditions that are, you know, impacts to crops, livestock, fire – you can kind of see the list across the top, and the bitly link under the title – is where you can go to report these.

And the reason I want to share this and emphasize this is a tool for you, as you can see, for this calendar year, we have two reports in the system for Wyoming. One was from January 20th and the other was from February 2nd, indicating one was for moderately dry and the other was severely dry conditions. But these type of reports are really invaluable to us. They they help to raise the flag to say hey there’s an issue here, or hey things are going really well here now.

And giving us that status update of the conditions out on the ground, because we can’t be everywhere and know what’s going on with this. I encourage folks to even mark their calendar to submit a report on, for example, the first of the month or the 15th of every month – and just have a time when you go in, and you log and tell us what the conditions are, maybe they’re just near normal, but to know that is really helpful. The other thing I want to offer on this is, that with the Condition Monitoring Observer Report System, you can also upload photos.

You know pictures speak a thousand words, and last summer, during the drought I was having individuals who would email me one picture, which is a picture that is in a point, you know, one point in time and one pasture – and it was a pasture I wasn’t familiar with. So, with the Condition Monitoring Report System, you can actually upload multiple photos. And I encourage individuals to upload comparison photos, so one showing what the conditions look like now, today, and find a photo from a year that was good or closer to near normal – and that was taken around the same time of year, and post those together.

And let us know like, hey this is what it usually looks like, this is near normal, and this is what it looks like today. That’s all very helpful for us. We do monitor this system on a weekly basis, as we’re looking at the US Drought Monitor, as well as the US Drought Monitor authors are also looking at the system. So, again it’s a way to raise the flag and keep us posted on the status of the conditions out on the ground. Next slide. So, with that I just want to thank all of our collaborators on the presentation, and the webinar today.

We have the USDA including the Northern Plains Climate Hub, as well as others that helped to organize this event. And NRCS was a part of it FSA, we also have National Weather Service, USGS, the Water Resources Data System, the State Climate Office. We also have the the Tribal Water Engineers, and the University of Wyoming Extension. .