Mountain West Discussion

[Mercurial]

On 12/17/2017 at 7:39 PM, Chinook said:

Yes, just 57" in the Montana Rockies. That's a significant contribution to the entire seasonal snowpack. Hard to read the colors on this over 30 or 32 here.

Some areas around GNP including Essex picked up 40".  Got 18" here.  About two feet of snowpack now. 

[ValpoVike]

1 minute ago, Mercurial said:

Some areas around GNP including Essex picked up 40".  Got 18" here.  About two feet of snowpack now. 

I only picked up 2.5" here, bringing my snowpack up to...well...2.5".  Happy to have it though!

[raindancewx]

I guess this can get wiped out if it is very wet the rest of the winter, but its been pretty dry in the NW & Northern Plains this winter to date.

Say its 40% below normal through 20 days of the 90-day winter in Seattle, where x is the anomaly needed the rest of winter to catch up to 0, i.e. normal.

0 = (-0.4 * .22) + (0.78x)

0 = -0.088 + 0.78x

0.088 = 0.78x,  x = +0.112

Needs to switch to 11% above average for the rest of the winter just to get to average.

I am somewhat hopeful that the precipitation anomalies in TX, NE Mexico will gradually shift north in late-winter and Spring, but we'll have to see.

[Chinook]

My place got 1.5" of snow yesterday.

[Chinook]

No wonder it was so cold while going to the airport today. We really did have single digits and negative single digits in the area.

Edit: DIA was down to 6 degrees on this day, but it doesn't show it at this hour on the map.

[raindancewx]

After looking a little deeper, 17 of my 27 wet Marches (>=1.2x long term mean precipitation) followed a December that was hot in the Northern Plains. For my 42 dry Marches (<=0.8x long term mean precipitation), only 14 were hot in the Northern Plains.  The Northern Plains, if you do a difference in proportions tests comes out as a statistically significant indicator. But I've been trying to figure out a way to deal with the exceptions in both the prevailing patterns:

Turns out, the dry Marches after a hot-Northern Plains December tended to be somewhat cold in the SW in December, and very warm in the NE in December, which is directly opposite to this year. The wet Marches after a hot-Northern Plains December tended to be near average in the NE and SW, which is much closer to this year. 

[mayjawintastawm]

We must have gotten under a band- been snowing nicely for about 3 hours and we have 2". Overperforming, if you can call 2" overperforming. Can't really tell about the band, since KDEN radar is down and all the adjacent ones are too far away and overshoot what's falling here.

[Chinook]

Looks like Fort Collins got 2" to 2.5" in my absence yesterday-- I saw some flakes in Ohio, anyway.

[Chinook]

This morning, the temp was 0 at Fort Collins-Loveland airport at 11z.

[raindancewx]

SOI is kind of hinting at a dry Northern Plains/Northern Rockies January - its crashed hard from +10 to +11 in Oct/Nov to +0.5 for the last 30 days, may finish December negative.

[mayjawintastawm]

Inversions the past 2 days really locked in the cold for a bit. Cherry Creek Reservoir went from ice-free to 95% frozen in the past 72 hours. One guy out ice fishing today already, which I would not recommend yet! 10-12 F all day and very light snow. Beautiful!

[ValpoVike]

5 hours ago, mayjawintastawm said:

Inversions the past 2 days really locked in the cold for a bit. Cherry Creek Reservoir went from ice-free to 95% frozen in the past 72 hours. One guy out ice fishing today already, which I would not recommend yet! 10-12 F all day and very light snow. Beautiful!

Yeah just drove thru Glen Haven where it was 9 degrees, but 8 miles later in Estes Park and 400 feet gain in elevation...35 degrees. 

[Chinook]

another big storm predicted for Montana, Idaho and Yellowstone NP.

I am back to Colorado now. There were no problems at O'Hare. It was -1F in Chicago and O'Hare was quite busy at 6:30AM. Sheesh. Glad to be away from airports. Every mile I traveled in the air today had snow under it.

[Mercurial]

ka ching

 

We've done a great job of making lemonade from lemons this winter.  Snowpack is a little lacking in northern MT east of the divide, but otherwise we're in good shape and AFAIK most terminals will finish the month with BN temps. 

[AfewUniversesBelowNormal]

Flagstaff will be 2nd longest on record without snow. If they make it to Jan 15th, it's 1st.. 

[raindancewx]

Looks to me like all the states in the US West, save maybe Montana are below normal for snowpack. Canada and Mexico doing pretty well for snow in the Western areas though.

https://www.wcc.nrcs.usda.gov/ftpref/data/water/wcs/gis/maps/west_swepctnormal_update.pdf

[Chinook]

Fort Collins had a surprise storm

[Chinook]

Snow pic from today. 3" of snow. The radar for this storm showed an extremely narrow area of snow that hit Fort Collins from about 1 AM to 5 AM. I didn't even think it was going to snow at all.

Edit:

Wednesday, low of 5.9, high of 50.2 with downslope winds.

Thursday, an after-midnight high temperature of 49.7 with downslope winds, low 22.5.

Friday, morning low of 21.8, then, with downslope winds, we had a record high of 68, and then, it was 12.4 degrees at 11:50PM.

[raindancewx]

Canadian thinks the NW stays pretty dry in January. Been dry everywhere this month, save Montana, Wyoming and West Texas.

[Randy4Confluence]

Any ideas  as to when this horrible Western ridge begins to break down over California? 

[raindancewx]

^^ I had the West pretty dry for the winter. That said...Spring kind of looks interesting. There are four routes to a wetter pattern for the West at this point I think:

1) MJO/SOI/trades move the coldest water out of Nino 1.2 into Nino 3 or Nino 3.4 by February/March while the Nina is still ongoing as the Canadian shows. Central tropics end up colder than Nino 1.2. This creates Modoki-Nina forcing, similar to an East-based Nino, and we get a wet period sometime between mid-February and mid-May in the Southwest before the storms shut down. It'd be the pattern from last Nov-Jan, but three months later essentially.

2) The warming subsurface below Nino 3.4 / Nino 4 reaches the surface (currently some +5C water near the edge of Nino 3.4 only 150m down or so). An SOI / trade burst causes the new warm waters and the old cold waters to mix out to roughly Neutral conditions, and they persist. Low solar activity with Neutral conditions can be cold/wet in April.

3) The MJO gets stuck in phases 2-3-4 longer than forecast. Even in a La Nina, that should eventually make California pretty wet. Or, we keep returning to those phases.

4) As seasonal wavelengths change, with the Nina collapsing, one or two very powerful storms get caught in places that haven't seen the storm track this Fall/winter. Without much steering, these cutoff systems produce 3-5 days of cloudiness, cold, and precipitation over the SW, per system. This becomes more likely with another big SOI drop, or if we move rapidly to El Nino conditions at the surface, which is what happened last Spring.

Statistically, Albuquerque has had no rain or snow for 88 days. Record is 109 days since 1891. Gotta end sometime. Also, every Nov-Apr has had at least one day of >=0.1" precipitation, we are at 0. My analogs had 8 days with >=0.1" for Nov-Apr, of which 4 days with >=0.2" for Nov-Apr, and of which 2 days >=0.3" for Nov-Apr.

 

[finnster]

On ‎1‎/‎1‎/‎2018 at 8:46 PM, raindancewx said:

^^ I had the West pretty dry for the winter. That said...Spring kind of looks interesting. There are four routes to a wetter pattern for the West at this point I think:

1) MJO/SOI/trades move the coldest water out of Nino 1.2 into Nino 3 or Nino 3.4 by February/March while the Nina is still ongoing as the Canadian shows. Central tropics end up colder than Nino 1.2. This creates Modoki-Nina forcing, similar to an East-based Nino, and we get a wet period sometime between mid-February and mid-May in the Southwest before the storms shut down. It'd be the pattern from last Nov-Jan, but three months later essentially.

2) The warming subsurface below Nino 3.4 / Nino 4 reaches the surface (currently some +5C water near the edge of Nino 3.4 only 150m down or so). An SOI / trade burst causes the new warm waters and the old cold waters to mix out to roughly Neutral conditions, and they persist. Low solar activity with Neutral conditions can be cold/wet in April.

3) The MJO gets stuck in phases 2-3-4 longer than forecast. Even in a La Nina, that should eventually make California pretty wet. Or, we keep returning to those phases.

4) As seasonal wavelengths change, with the Nina collapsing, one or two very powerful storms get caught in places that haven't seen the storm track this Fall/winter. Without much steering, these cutoff systems produce 3-5 days of cloudiness, cold, and precipitation over the SW, per system. This becomes more likely with another big SOI drop, or if we move rapidly to El Nino conditions at the surface, which is what happened last Spring.

Statistically, Albuquerque has had no rain or snow for 88 days. Record is 109 days since 1891. Gotta end sometime. Also, every Nov-Apr has had at least one day of >=0.1" precipitation, we are at 0. My analogs had 8 days with >=0.1" for Nov-Apr, of which 4 days with >=0.2" for Nov-Apr, and of which 2 days >=0.3" for Nov-Apr.

 

Thanks Raindancewx - wow 88 days that is a long, dry streak.  You are right - something's gotta give soon and deliver some moisture to the West, this has gone on long enough.  I have been mainly staying away from weather forums/outlooks lately just because it's so damn boring and frustrating, but believe me I keep hoping for a positive change.  Each day that passes brings us closer to that change (that's the best positive spin I can put on this bad situation). 

[AfewUniversesBelowNormal]

Not really any signs of it for a while.... In other words, the pattern is much different from 1950s or your classic La Nina

[raindancewx]

The European actually has been consistently showing a lot of precipitation next week, even though the GFS does not have it. I've been targeting the Jan 7-14 period for a while now, we'll see. The dry-streak would break around 1/11/18 if the European is correct.

The record here go back to 1891, so you can make the case that no-precipitation in a 90 day period is a 4 standard deviation event, based on how few 90-day periods go totally precip free.

[AfewUniversesBelowNormal]

Interesting times. We are seeing possibly the deepest winter low on the east coast since the 1800s. 

[raindancewx]

Ten closest SST years to Dec 2017 in Nino 1.2, Nino 3.4, Nino 4. are: 1956, 1961, 1962, 1967, 1971, 1974, 1995, 1996, 2000, 2005

December 1956 objectively closest....and just like this year had no precip in Albuquerque in December.

Dec        4          3.4        1.2      Obj
2017    28.05    25.62    21.44    0.00
1956    27.89    25.71    21.49    0.30
1995    28.04    25.65    21.96    0.56
1962    27.74    25.67    21.72    0.64
1974    27.42    25.63    21.35    0.73
2005    28.28    25.68    21.89    0.74
1971    27.86    25.37    21.82    0.82
1996    28.35    25.95    21.68    0.87
1961    28.00    25.97    21.93    0.89
1967    28.15    25.95    20.97    0.90
2000    27.59    25.68    21.85    0.93

Top-heavy weighted blend of the top years is fairly close to December. A blend of 1996 & 2007 produces 2017 pretty easily, but its way off for observed temps nationally in Dec, since the timing of the cold seems a week late or so.

1996    28.35    25.95    21.68
1996    28.35    25.95    21.68
2007    27.42    25.01    21.15
Mean    28.04    25.64    21.50
            
2017    28.05    25.62    21.44

 

[Chinook]

This is a little off topic, but the NWS surface analysis has has 951mb offshore. Gee. You don't even see that sort of thing much in Kocin+Uccellini's book. 

The GFS has snow for Colorado on Wed/Thu (162hr) - could be definitely something to watch - the Euro has a strong low in Colorado/Kansas. I figured the pattern had to change to a wetter pattern for the West. I don't know how much to really get my hopes up for my house.

[raindancewx]

European and GFS both have pretty healthy precipitation totals in New Mexico now around 1/11. We're almost close enough now that I believe it. Of the 5 streaks here with 90 days or more in a row of no-precipitation, three broke in the week of 1/7 to 1/13. Most of this would be snow presumably for the mountains, valleys, maybe rain and some snow.

[Chinook]

Come on, northern Colorado storm

[raindancewx]

Wish the MJO products would update, its not super hard guessing what phase it is from satellite depictions of cloudiness, but the magnitude is hard to estimate.