• Member Statistics

    16,018
    Total Members
    7,904
    Most Online
    anathema
    Newest Member
    anathema
    Joined
Chinook

Mountain West Discussion

Recommended Posts

On 1/11/2020 at 9:14 PM, snowfan789 said:

Nothing particularly substantive to add. But, to state the obvious, what a quite horrible pattern for the CO Front Range since early December. No clear end in sight. No significant precip. No real cold. Just downright oppressively sunny and boring. Ugh. That is all.

Only good thing is I'm able to keep up my normal 3-season exercising - kind of like an extended, coldish Fall. I've been on my bike more since the Solstice than I have in any other year ever. This is getting really, really boring though.

Share this post


Link to post
Share on other sites

I kind of assumed that nothing would happen for a while. Then the GFS and Canadian came up with different versions of this storm in about 1 week. The Euro does not have this. It has a trough in New Mexico and a trough in Montana at this time frame.

SedqVKx.png

Share this post


Link to post
Share on other sites

There is SOI support (crash 1/10-1/12) for a big storm passing through the SW around 1/22-1/23. Models likely have the right general idea. I'd expect something around 1/25 too. 

Share this post


Link to post
Share on other sites

Next week's storm could potentially happen on Wednesday. There are still pretty large differences between the GFS, Canadian and Euro. The situation is similar in many ways to my post yesterday. The Euro still has the 500mb troughs in two places, Montana and New Mexico. The GFS has somewhat flip-flopped today, but the 00z GFS came back with a big snowstorm with a 500mb closed low for Denver. The Canadian has a concentrated 500mb trough, but has snow mainly for the Sangre De Cristo mountains. 

 Some days, I think the Canadian tries to do the same things as the GFS, but always comes out with worse accuracy.  In this particular case, I don't know if there will be a storm. These (terrific) days, you can even check the Euro ensemble members QPF (for free) and they have some large differences in QPF.

Share this post


Link to post
Share on other sites

This may be a similar situation to mid-November when a storm from the Polar Jet came through Colorado, while a storm from the Subtropical jet came through New Mexico, at slightly different times, but only a day or so apart. 

In other words...GFS is right to hammer Colorado and the Euro is right to bring a lot to New Mexico. That's happened in the recent past in this pattern.

I'm inclined to believe there is at least one more big storm for NM before the end of January. Very strong signal for a wet January here after a wet November. We're half way there after yesterday.

I'm increasingly eyeing Feb 25-Mar 7 as a pretty volatile period for the Rockies, probably with heavy snow. Some things that I consider relatively independent support a big March:

1) 1992-93/2004-05/2018-19 have all been fairly close at times to the Fall/Winter pattern. Some pretty notorious March storms in those patterns. 

2) The patterns have been operating in repeat mode nationally at about a 3.5 month lag, so the H2 November storminess should come back about March,for two weeks. The 1/16 storm in New Mexico roughly corresponded timing wise to the 10/4 storm in New Mexico. The idea is 9/16-10/15 is roughly January, so 11/16-12/15 is roughly March.

Image

3) There have been unusual and fairly severe transitions between extreme dry air and wet air (by NM standards) during transitional phases of the national pattern. Going from a 57F / 3F dew point to snow 32F/ 30F is not super common as a 24-hour transition without a strong cold front...but it just happened, and has occurred several times already since October.

4) There is a late peak or at least a big secondary +ENSO peak coming in through the subsurface. There was a big peak in October preceding the November madness late in the month.

ImageEquatorial Pacific Temperature Depth Anomalies Animation

5) Since Fall 2007, March has been wet exactly one time in New Mexico (2019), and it hasn't been cold in any year. April has seen more snow than March in Albuquerque since 2010, a month that is often only freezing or colder for something like six-ten hours at most with frequent highs in the 60s-80s, while March has 20-40 hours below freezing even in a warm year, with much colder highs. There has been a lot of dumb luck non-sense for March snow. The consistent lows <=freezing to date (62 for 10/1-1/18, 34th most since 1931-32) and very dry air alternating with rapid transitions to wet air should help out with allowing March snow. Years with snow in Nov, Dec, and Jan are fairly rare here, but they tend to have snow more often in March (21/25 cases) compared to other years (37/63 cases) at statistically significant level. It's only snowed 3"+ twice since 1900 in March in a low solar year, but even ~3% events happen sometimes. The dry monsoon years prior to El Nino are often a bit better for March snow too.

  • Thanks 1

Share this post


Link to post
Share on other sites
23 hours ago, smokeybandit said:

GFS lost the NW Colorado storm the last two runs

It looks like this storm is gone for good. The GFS was too happy with a closed 500mb low. One of the biases of models, in general, is to create more phased lows and huge storms. (in the long range, 7-10 days.)

Share this post


Link to post
Share on other sites

Quite a stark picture for eastern CO, even more remarkable considering that period is one of the driest climatologically.

We have angered the gods. What did we do? What needs to be sacrificed?

Share this post


Link to post
Share on other sites

Probably best to just joke about the lack of snow in the CO Front Range during winter, so far, when (I think) it is most fun to have snow because of what just “feels” normal, and because of the low sun angle causing snow to actually stick around. But, seriously, what a historically awful stretch of boring dry weather since late November. The Fall was mostly great; however, this is so far without question  the worst winter I’ve experienced since moving to near Denver in 2013. No real cold & incredibly dry. Ugh. Hopefully this is not the new normal.

Share this post


Link to post
Share on other sites

There were some heaps of lenticular clouds today. I haven't posted a picture of clouds or mountains for a long time, I think.

ilOjKKd.jpg

Share this post


Link to post
Share on other sites
On 1/24/2020 at 8:16 PM, snowfan789 said:

Probably best to just joke about the lack of snow in the CO Front Range during winter, so far, when (I think) it is most fun to have snow because of what just “feels” normal, and because of the low sun angle causing snow to actually stick around. But, seriously, what a historically awful stretch of boring dry weather since late November. The Fall was mostly great; however, this is so far without question  the worst winter I’ve experienced since moving to near Denver in 2013. No real cold & incredibly dry. Ugh. Hopefully this is not the new normal.

I moved here from the snow plagued mid atlantic in August.  You can blame me

Share this post


Link to post
Share on other sites

There's the late October record cold, showing up right on time (3.5 month lag) - obviously way out in model fantasy land. But it's nice to see that, as opposed to a huge warm spell.

QmZ0WIY.png

  • Like 1

Share this post


Link to post
Share on other sites

Good morning all.  I have mainly stayed away from weather forums since this exceedingly, boringly stretch of weather started in December (after a great Oct|Nov pattern).  Hard to believe after such a great fall that every storm now misses the front range.  Thankfully our mountains are getting regular, albeit smaller, storms.

I’m just interested in any explanations as to how/why the pattern changed so drastically for the front range, and the prospects to get back to some semblance of stormiest in the weeks and months ahead?

BTW I was about to suggest we cancel the winter thread and move to a spring thread, but I don’t want to over-react.... :wacko:

Share this post


Link to post
Share on other sites

A mix of rain and snow is happening at Denver, Colorado Springs, and Fort Morgan this afternoon. As per the radar, I don't think too much has happened in Denver city.

Share this post


Link to post
Share on other sites

WT360 has a pretty good track record for seasonal stuff, and they have similar to more snow in March for NM/CO compared to 2019. Given the pattern has been cycling at a 3.5 month lag, the first half of March is my best guess for a repeat of the late November part of the pattern.

zLIBWyq.png

Share this post


Link to post
Share on other sites
14 hours ago, raindancewx said:

WT360 has a pretty good track record for seasonal stuff, and they have similar to more snow in March for NM/CO compared to 2019. Given the pattern has been cycling at a 3.5 month lag, the first half of March is my best guess for a repeat of the late November part of the pattern.

zLIBWyq.png

Thanks for the post!

Share this post


Link to post
Share on other sites
On 1/24/2020 at 8:16 PM, snowfan789 said:

Probably best to just joke about the lack of snow in the CO Front Range during winter, so far, when (I think) it is most fun to have snow because of what just “feels” normal, and because of the low sun angle causing snow to actually stick around. But, seriously, what a historically awful stretch of boring dry weather since late November. The Fall was mostly great; however, this is so far without question  the worst winter I’ve experienced since moving to near Denver in 2013. No real cold & incredibly dry. Ugh. Hopefully this is not the new normal.

I’m a recovering weatherholic myself and I definitely agree with you, this has been one boring winter so far.  I’ve been in Colorado a long time.  To give some perspective, IMHO the 1970’s and 80’s were in another league when it comes to cold and snow on the front range (just peruse the weather records for Denver back then).  The 1990’s were less so, and since about 2000 cold and snowy winters have far and few between.

If you believe in longer term weather cycles/patterns repeating (I do), a pattern more reminiscent of the ‘70s and ‘80s could return.  But if and when - nobody truly knows.

Share this post


Link to post
Share on other sites

The first winter weather advisories/watches for this storm have been issued for central Nevada up through Wyoming, including Salt Lake City. In Colorado, our area will probably get some light upslope snow on Monday, with higher snow rates later on Monday as the 500mb low approaches and the lift increases. I am hoping the heavier snow doesn't start too early on Monday, but 5:00 rush hour may be challenging. Overall, this is a pretty decent setup for snow with some easterly 700mb winds here east of the Rockies. The last time it snowed here was December 27-28th with 1.5". So the last two months were pretty much uneventful except for a few days with wind gusts, and hardly any days that were very cold. We have had just a few days with a high temperature below 40 since December 31st. I would think that we are on track for a colder week or two weeks after this.

HN9UsIR.png

 

by the way, this happened a few days ago in Colorado. read the text carefully

Rvhymcx.jpg

 

Share this post


Link to post
Share on other sites

Interesting forecast here: This is the snowiest run of the UKMET I have ever seen for our area. UKMET snow products have been on Pivotalweather since Monday or Tuesday. Otherwise, I haven't checked UKMET precip for years. Those people at Pivotalweather really must be something else to have full ECMWF data and full UKMET data.

GRaKAfq.png

Share this post


Link to post
Share on other sites

If you look on the first or second page of the thread, there was a pretty decent snow event for Colorado in mid-October, around 10/19. That's roughly the 3.5 month lag I've been talking about.

Remember this?

fp8ikSC.png

Share this post


Link to post
Share on other sites

The 12z GFS has 9-14" for the Front Range cities, with over 12" very close to me. The NWS gridded forecasts still have 5-6" at Fort Collins with 8" at Boulder, 6-7" for Denver. This may be a time when this type of graphic showing Kuchera-ratio snowfall of over 20:1 doesn't really happen because the snow packs down better than that.

pv8pjuz.png

Share this post


Link to post
Share on other sites

Today, Denver tied a record high of 74 set in 1934. (Interesting note: the winters of the 1930's were not generally as much above average as the dust-bowl summers.) Fort Collins had a record high of 74.

Two places in Colorado hit 80 degrees today.

A winter weather advisory has been issued for the Front Range cities, and a winter storm warning issued for areas over 6000 ft. Also winter storm warning for Boulder County, Jefferson County.

Share this post


Link to post
Share on other sites

My area dropped from 72 to 20 degrees in 24 hours, which is quite a shock, certainly about the highest 24 hour temp drop that I've experienced in Fort Collins/Loveland. My area has 4.5" of snow. Much of that fell in the morning with some nice dendrites. Freezing drizzle fell early in the day just before the snow started, and my car had a layer of ice on it in the morning. This was very annoying.

The weather models are now beginning to agree on a northwest-flow snow event on Friday-Saturday for my area.  The GFS has up to 0.9"-1.0" of QPF for Fort Collins and Cheyenne and also some high amounts for mountains north of I-70. In my opinion, northwest-flow snow events can be tricky, 700mb winds would be downsloping while snow is falling, which doesn't always work together well. 

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...

  • Recently Browsing   0 members

    No registered users viewing this page.