Mountain West Discussion

[smokeybandit]

Got 6" or so here.  My first "real" snow experience after moving from Maryland and the fact schools didn't close is such a wonderful thing.  In MD they'd close for an inch of snow, or even the threat of snow.

[Chinook]

I had about 3" on elevated surfaces and 2.5" on the ground. I reported 2.5" to the NWS last night and that seems the most reasonable. It continued to snow after 10:00PM last night, but obviously not much accumulated.

On to round two!

[Chinook]

Graphics from NDFD

 

 

graphics from NWS Boulder Denver

[ValpoVike]

2 hours ago, Chinook said:

I had about 3" on elevated surfaces and 2.5" on the ground. I reported 2.5" to the NWS last night and that seems the most reasonable. It continued to snow after 10:00PM last night, but obviously not much accumulated.

On to round two!

Round two looks to be much more productive down your way.  Up here we underachieved, despite steady snow all day I ended up at 7".  This is about half of what I was expecting, but I'll take it

 

[Chinook]

NWS lowered the snow forecast values in the north and in Wyoming

[Chinook]

A storm report from DIA said 5.9" of snow. There was a heavy snow band east of DIA. For my area, we have got storm reports of 3" or more west of I-25. I can't really tell how much has fallen, but it's probably 2-3". Since we had some snow on Sunday, it's kind of hard to tell.  It is 14 degrees here, so that is like a mid-January arctic temperatures. It's certainly not very helpful for the roads.

[smokeybandit]

My forecast was 8-12", gonna need a couple inches from these last couple bands to get to 8"

[donsutherland1]

At 8 pm MDT, Casper, WY had a temperature of -8°. That surpassed the -4° temperature of October 27 as that city's coldest October temperature on record. Casper appears headed for its coldest October on record. The lowest October mean temperature was 37.0°, which was set in 2009.

Today's 8° high temperature in Casper is, by far, the earliest maximum temperature below 10°. The prior record was 6° on November 11, 2014.

[donsutherland1]

Yesterday's low temperature of -9° was Casper's lowest October temperature on record. The previous record was -4°, which was set on October 27 this year. The October 27 temperature was also Casper's earliest subzero reading on record. The previous earliest reading was -1° on October 29, 1971.

In addition, today saw Casper record its fourth consecutive and fourth subzero low temperature of October. Previously, the October record was two days on October 29-30, 1971.

[Solak]

 

[smokeybandit]

I bottomed out at -1.  -45 would be a bit too chilly.

[olafminesaw]

2 hours ago, Solak said:

 

The craziest thing to me is that the bottom was 40+ degrees colder than the top

[Chinook]

8-12" forecast was a bust for much of the Denver area. 6-8" was a bust for Fort Collins/ Loveland. Certainly, things were slippery though, so it had an impact. It's not like it just melted off the road or anything. I think my storm total is about 4".

 

[mayjawintastawm]

We got 7.5" from round 2, more than half of which fell 6 AM-9 AM yesterday. Low of +6 F this AM. With 5" from round 1, and 7" total from the other two snows, we have 19.5" total for October. Never, ever thought I'd be posting this a month ago!!

[Chinook]

Fort Collins -CSU station has got 7.3" of snow since Saturday. The monthly average temperature is 46.2, which is 3.7F below normal for the month. We will finish the month with temperature departure colder than -3.7F. By the way, I had to go to the Midwest Regional Climate Center web site to look up these values for our co-op station (non-airport.) The NOWDATA on the NWS web site has not been working since earlier in October. Perhaps they should call it "THENDATA," because it worked *then*, but it doesn't work now.

[Chinook]

CoCoRAHS snow plots

 

[raindancewx]

3 hours ago, Chinook said:

Fort Collins -CSU station has got 7.3" of snow since Saturday. The monthly average temperature is 46.2, which is 3.7F below normal for the month. We will finish the month with temperature departure colder than -3.7F. By the way, I had to go to the Midwest Regional Climate Center web site to look up these values for our co-op station (non-airport.) The NOWDATA on the NWS web site has not been working since earlier in October. Perhaps they should call it "THENDATA," because it worked *then*, but it doesn't work now.

You can use this site for now - this is essentially the http://xmacis.rcc-acis.org/ site, but it is still up and working.

http://scacis.rcc-acis.org/

[raindancewx]

This October finished about 2F colder in Albuquerque than my analogs had it. I think it's going to finish with an average temperature of 55.4F for the city - coldest since 1986 if that is correct. It's a top 10-cold October here for the past 100 years.

Also pretty sure that Jan-Oct is now running about 2F colder than in 2018 locally, which is a lot for a 10-month period, when there is only about six degrees of variation on an annual basis for the past 100-years, and that 2F drop is even after a very hot period in late Summer, mid-July to mid-Sept essentially.

How did you fair in the local rankings for October in Colorado?

[snowfan789]

3 hours ago, raindancewx said:

This October finished about 2F colder in Albuquerque than my analogs had it. I think it's going to finish with an average temperature of 55.4F for the city - coldest since 1986 if that is correct. It's a top 10-cold October here for the past 100 years.

Also pretty sure that Jan-Oct is now running about 2F colder than in 2018 locally, which is a lot for a 10-month period, when there is only about six degrees of variation on an annual basis for the past 100-years, and that 2F drop is even after a very hot period in late Summer, mid-July to mid-Sept essentially.

How did you fair in the local rankings for October in Colorado?

Well for October: https://www.weather5280.com/blog/2019/10/30/third-snowiest-october-for-stapleton-4th-boulder-5th-colorado-springs/

[raindancewx]

I had 2009 as my top weighted analog this winter (3/10 of my blend), so its nice to see relatively close highs and snow in Stapleton. 

The cold Junes / warm late Summer / cold October is pretty interesting for NM and CO, it's not something that shows up a lot in the records. It seems to tie into year that have blocking but also "stuck" MJO patterns in the last 40 years. 

This winter seems like it could feature a lot of drier than normal snow across the West. I really don't have a strong precip signal in the data I look at, but snow still looks average to above average generally.

[snowfan789]

On 10/31/2019 at 9:40 PM, raindancewx said:

I had 2009 as my top weighted analog this winter (3/10 of my blend), so its nice to see relatively close highs and snow in Stapleton. 

The cold Junes / warm late Summer / cold October is pretty interesting for NM and CO, it's not something that shows up a lot in the records. It seems to tie into year that have blocking but also "stuck" MJO patterns in the last 40 years. 

This winter seems like it could feature a lot of drier than normal snow across the West. I really don't have a strong precip signal in the data I look at, but snow still looks average to above average generally.

Do you mean snow that’s relatively low in water content when you say drier than normal? Odds of an above average snowfall season are almost 75% based on historical data and Denver receiving over 10” in October. There are no guarantees, of course.

[smokeybandit]

Well it only makes sense that the season goes above average when you get extra snow in a time period not typically known for significant snow.

[snowfan789]

There are a lot of years that fell more than 10” short of average. So, the data indicates a heightened potential for more snow relative to normal after October.

[raindancewx]

I have mechanisms for estimating "snow ratios" in the West when I do my analogs, and yes, the general idea is relatively dry snow occurring fairly often. Think 22:1 ratios instead of 17:1 if 17:1 was your average.

 

[snowfan789]

The ratios for the two recent snowfalls in Denver were 15-20:1(ish), which is very dry for October.

[raindancewx]

I keep seeing people referencing 2013...but the October pattern was far more amplified than that year. 2018 is not too far off in the East though for October. I saw this elsewhere:

 

[MidlothianWX]

The official October snow total at the Boulder measurement site was 26.4", making this the snowiest October since 2009 and the 4th snowiest on record.

The official mean temperature was 45.7, making this the coldest October since 2009 and the 5th coldest on record.

[Chinook]

Things are getting back to being sort of normal here. The snow has melted, and eastern Colorado looks greenish on satellite images except for Elbert County. There is still some snow in the shaded spots. Yesterday, we had a high of 57, and today was 49, with mostly clear conditions recently. We have had a few clouds including some lenticular clouds recently. NOWDATA is back in operation, and Fort Collins got 10.3" of snow in October, which is fairly similar to October 2011, but we had the snowiest and coldest October since 2009. Fort Collins had 5 degrees on Halloween, which was the coldest low temperature on Halloween since 1991, which was 4 degrees. So, essentially, 4 degrees was the coldest Halloween in modern times. My place had about 8.7" of snow in October.

 

Interesting note: in the 2003-2004 to 2018-2019 time frame, Boulder Co-op station averaged 89.5" of snow, Fort Collins averaged 48.2".  Boulder's value in this time frame is ABOVE the 1981-2010 climo of 87.7", but Fort Collins is BELOW.

[raindancewx]

The MJO now looks like it will be a pretty coherent force for at least the next week. We're probably going to get into phase 8 around mid-month, which times up well with the recent huge SOI crash for a big storm somewhere in New Mexico or Colorado. Phase 8 MJO is pretty wet in November here I'm pretty sure. We should get some rain this week too, will be the first November precipitation of any kind for Albuquerque since 2016.

[MidlothianWX]

Here is an interesting graphic that was sent to me by the Boulder COOP observer - the all-time largest snowstorms at the official Boulder measurement site(s). He did say that the data pre-1990 is suspect as measurements were only taken once per day up until that point, so there are probably a few storms that had higher totals than was reported. Anything pre-1948 is taken from newspaper accounts. Notice the total lack of January storms!