Monday, January 31, 2022

Here we go again - on several levels

If you didn't get to see the brief posting I did on the 24th, you can read it here.  Actually please do read that submission.   In that post I discussed the large range of possibilities of snowfall amounts that were expected with the upcoming storm.  Forecasting snow totals is a complete WAG as there are so many unknowns.  The storm in question definitely produced banded snowfall as I expected.  But for that main band to produce 18-24 inches is WAY off the charts!  There is simply no way to expect that type of snow generation from any storm.  

I've mentioned in several presentations I've done that snow making by the atmosphere is highly dependent on many variables, but is REALLY impacted the greatest by what is called the dendritic growth zone.  If there is solid ascent (rising) of the air in this zone (between -12 and -18 deg Celsius) with ample moisture (saturated air), then heavy snow can develop.  But typically this growth only last several hours and the zone of growth moves around.  During banded events, the snow can become intense and then when these bands remain stationary the amounts add up fast, such as what happened on the 25th.   

The band of very heavy snow (greater than 18 inches) was no more than 10 miles wide but the area of amounts greater than 10 inches was a bit wider.  The day after the satellite image showed the snow field...

Even as of this morning (31st and 6 days later) you can see how much was still around!

Different topic....

My extreme pet peeve....FAKE WEATHER!   There are so many people that post graphics and pretend to be Meteorologists and SO many people that follow them (and then often share the crap that is displayed).  I talk about it in every presentation I do.  The latest example from a few days ago by a Facebook poster that TOO MANY people follow him/her....  here was that post....

This one REALLY ticked me off because people I know started sharing it.   In reality, lows up in the Dakota's and Minnesota might get as cold as -30.  Typical for most winters up there.  This person also indicated 2 feet of snow across Nebraska and Iowa.  They might not even get a dusting.   This type of fear mongering goes on way to much in social media.  

 Off my soap box.

I still need to do more analyzing before I venture into the spring and summer outlook.  For now we'll be dealing with another storm, unlike last Tuesday but impactful just the same across a much larger area.  Just like the last event, computer forecast models are pretty useless.  Look at the outlook from various models for Dodge City as an example.  A dusting to 12 inches!  

Look at Kansas City....3" to 25"!  

Come on...are you serious?  This time the actual track of the upper storm will be most critical, plus a big question is will the storm come out in pieces (less snow) or be more concentrated?  Given the lift of moisture across Texas up and over the increasingly cold airmass with at least some upper level forcing, I think a large area of 4 or more inches can be expected across the high plains of Kansas, Colorado and into the panhandles and points east. I'm sure there will be pockets of 6 plus.  Actual moisture content may end up between 1/4 and 1/2 inch but the snow will blow around.

After this event, it appears we might be going back into a drier trend and eventually much warmer once the snow melts.  I'll see if I can finetune that outlook and dig into the later winter and spring outlook in the next posting.

Monday, January 24, 2022

Brief update - Jan 24, 2022

 Before I get into the meat of the outlook for the spring-summer-end of the growing season, I'll need a bit more time to do some more analyzing.  The picture is becoming a bit more clear but I need to look a bit more data.  

I thought I'd just briefly mention some of the difficulties in making a "short term" forecast for the high plains.  Take this upcoming event as an example.  Looking at the upper air chart this morning...

A disturbance in the upper atmosphere over southwest Canada was moving south-southeast this morning  It is expected to intensify as it drops south before turning east.  Forecasts being made for the expected surface weather across the high plains for tomorrow (Tuesday) and into Wednesday will have to settle in on several assumptions, some assumptions that won't verify.  

1) Will the system take a track as indicated by the red line?

2) Will the system continue to intensify as it drops south?

3) What will the impacts be if the system turns east more quickly, or even later and farther south?

4) What will the moisture profile be like to feed this system?

5) What will the ice crystal and eventual snowflake temperature profile be like - all dependent on the growth zone of the ice crystals.

It is certain (100 percent) that this system WILL produce an area of snow across the high plains.  But what will the areal extent be (how far east) and coming up with an amount for any one location (both snowfall and moisture content) is purely speculation and a WAG.   You might ask, "won't computer forecast models help out since the event is less that 24 hours away?"   Ha!  Look at what the various computer forecast models have for Dodge City.  That is a range from a dusting to almost 8 inches!  Ridiculous! 

The same extreme variance is indicated for other locations.  Since this system is likely to produce banded snowfall, there should be NO confidence until the snow actually starts to develop and the upper system has made it's turn.  That means that the lead time with confidence may only be hours.  It's the way it is with forecasting sometimes.

That leads me to the outlook for the growing season.  If there is this much difficulty with just one minor weather system, how can forecasts months and seasons in advance have any validity?  It's tough!

What I try to do is pick out periods of opportunity.  For instance, in my last post I did on the 12th, I said "Other than a few days of possible precipitation with the cold air later this month, I'm afraid that February may follow January with several outbreaks of cold but with not many chances for precipitation = maybe just a couple."  This storm for tomorrow may be it for the balance of the month. Another shot of cold or two so nothing mild or warm is expected.  There is "some" hint of changes for that first week of February and I'll address that on the next blog posting (hoping to do that before the end of the month).

But for now, let's hope this system brings at least a small gift for many of us.  Those that get under the bands will benefit the most and may get up to 1/2 inch of moisture in the snow.  Others it should be under 1/4 of an inch, but at least it's something.

Wednesday, January 12, 2022

Pathetic weather continues unabated - Part 2

Since the last posting on the 23rd of December (you can see that here), there was at least a little bit of precipitation - an actually a fair amount for select areas (all things considered for the winter time).  Two separate snow events (Jan 1 and Jan 6) dumped 6 to 10 inches on an area of western Kansas.  A satellite image from Monday shows what is left (the bright area was the heaviest)....

Unfortunately, most of us had less than 1 to 4 inches and the snow was accompanied by wind.  The snow really wasn't as dry as might be expected but it really did not help with the drought situation (other than that small area noted above).

Instead of posting the drought map as I usually do (which takes into consideration hydrologic data - not just precipitation), I'm posting the Palmer Drought Index which can be more representative of soil moisture in addition to precipitation deficits.

The pattern is cycling, just like it does every year, but I'm having a difficult time discerning the actual time scale.  I see evidence of 41 to 44 days but also as long as 82 days.  There was some thought too of around 60-65 days but I'm just not seeing it at this point.  Regardless, it is a really awful pattern as far as getting a decent amount of moisture.  There is hope for spring but I'm afraid that the pattern will yield the best chance farther east.  For the high plains that would equate to some really windy, warm and dirt storm days, much like occurred December 15.  I'm not ready to panic on the March through May period just yet - so hold on.

In the near term, there will be an impactful storm at the end of the week but it will not bring much if anything to the high plains, other than another bout of high wind and brief colder temperatures. Looking at the jetstream map....

The big red X off the northwest U.S. coast is the storm that will take the track as indicated by the red dashed line.  It will be referred to an Alberta Clipper (common winter type storms).  It will then tap into the Gulf and become a MAJOR winter storm for the eastern part of the country over the weekend.  They will get pounded!  

Any hope for something for the high plains may come with the next shot of really cold air and that is due around January 22, give or take a few days.  I see strong possibilities of a 2 to 4 day period of much below normal temperatures.  Details this far out are unknown, but I would think it will be at least as cold as it was the first few days of this month, i.e., a couple of days of sub zero temperatures (highs in the single digits).  The good news is that the cold stretch should not be prolonged.    With that cold air, I see a pretty good chance of some precipitation - likely in the form of frozen.  But unfortunately, it probably won't be a huge amount but I guess anything would be good at this point.

So is this awful pattern the result of La Nina that I'm sure everyone has heard about?  I've said it before.  La Nina or El Nino only "contributes" to the pattern.  We are in a pretty good La Nina at the current time.  But to make a forecast based on that?  Look at what has happened during past La Nina events.  No two are alike and we often see a wide range of weather across the high plains during each one.  

Here is the anomaly of precipitation during La Nina events (November through March)...

Here is the anomaly of temperatures during La Nina events (November through March)...

So with the vast differences from one to another, how can one make an accurate predication of what is to be expected based on La Nina (or El Nino)?  

The current sea surface anomaly has this....

The cooler than average (La Nina event) definitely is notable from south America west along the equator.  But what about that warm blob across the north Pacific?  What about that cool area in the gulf of Alaska?  That may or may not have an impact.  Believe it or not, the northwest Atlantic warmer than normal waters may also be having an affect.

One huge concern I have is the above normal waters in Gulf of Mexico.  There will likely NOT be major intrusions of Arctic air into the gulf this winter (maybe very briefly).  Thus, I suspect that waters there will be very warm as spring approaches.  I already mentioned in posts this past fall that the pattern was set up for above normal tornadoes for Kansas for 2022.  I'm not completely sold on western Kansas but eastern Kansas (and points north and south) will likely be under the gun several times.  This warm gulf will be the source for the rich moisture needed.  Hopefully though, this would also equate to a potential source for moisture for some of the high plains if a weather system can get going west of us.  More on that later....

So, going forward.  Other than a few days of possible precipitation with the cold air later this month, I'm afraid that February may follow January with several outbreaks of cold but with not many chances for precipitation = maybe just a couple.  Fingers crossed.  As March arrives, perhaps there will be an improved chance for beneficial precipitation, but I'm not getting my hopes up for now.

Next week (Tuesday and Wednesday, 18th-19th) I'll be presenting at the Cover Your Acres Winter Conference   in Oberlin.  Perhaps I'll see a few of you there.