Mountain West Discussion

[raindancewx]

I've been looking hard at years that had a super-cold Nino 1.2 in January on this data-set since Nino 1.2 was the coldest it has been (23.32C) since January of 1981:  https://www.esrl.noaa.gov/psd/data/correlation/nina1.data

Definitely some interesting Marches after Nino 1.2 is that cold in January. Hardly any readings in January that are even within 0.4C of how cold Nino 1.2 was in my lifetime. Something like 4/13 of my wettest Marches since 1950 show up in the close matches.

The January Nino 1.2 readings w/in 0.2C of 2018: 1956, 1971, 1974, 1975, 1976 

The January Nino 1.2 readings w/in 0.4C of 2018: 1950, 1955, 1959, 1963, 1967, 1968, 1981, 1997

Not exactly a lot of recent analogs.

Only two had a -SOI in February, which is close to a lock at this point as its -17.8 Feb 1-16: Jan 1959 (-15, 23.69C), Jan 1981 (-4.2, 23.06C)

 

 

[AfewUniversesBelowNormal]

Nino 1.2, what about New Zealand? Someone said they are +6.1 and the record is +2.9. It's short term land torque

[Chinook]

The 00z GFS seems to be getting more consistent with other GFS runs. The Euro is not too far off. It looks like Longmont to Cheyenne could get 0.3" - 0.45" of QPF and Denver may get in on this 0.3"-0.45" or possibly get less snow. Snow ratios could be higher than 10:1 for sure. Pivotaweather says Kuchera ratios are 24:1 for my area on Monday night, and I am not believing that till I see it, because 24 is a much bigger number than 10.

[raindancewx]

The storms coming in this week do look fairly cold, the local NWS was talking about -11C to -12C at 700mb over Albuquerque on Tuesday last night. So that would give high ratios.

My eyes will be on late next week - the SOI is still -17.0 for 2/1 to 2/17, but I think the MJO is going to speed up soon, and we'll be near phase 1/2 by 2/24 to 2/26.

 

[Chinook]

There's going to be snow from New Mexico to Quebec at this time period on Mon/Tue

[raindancewx]

Looking pretty cold with the coming system. I think we'll get some snow in the city with this one.

It's amusing to see that Philadelphia will probably hit 70F this week, maybe twice, before Albuquerque has.

We haven't been in the 70s since Nov 17 here, and its not looking like it will happen for at least the next week. This is already the latest first 70F timing since 2013. Last year it hit 70F on 2/10. In 2013, didn't hit 70F until 3/13. Long-term average for first 70F day is 3/8 here.

Getting somewhat concerned for areas east of me, looks like the MJO wave is going to make it to phase two at fairy high magnitude in late February, then phase three around March 1st. Could be a pretty good severe outbreak after we get to phase two.

[Chinook]

a pretty quick dropoff in temps for Casper to 5 degrees.

[ValpoVike]

Oh, please make this little nugget true in this morning's AFD update.  I haven't seen thunder snow since my days in the midwest.

Next thing will look at will be potential for thunder in the high country later
today. A very convective look on satellite and webcams, with
around 200 J/kg of forecasted CAPE pushing in from Western
Colorado.

[mayjawintastawm]

Under a nice band right now, moderate+ snow with visibility about 1/3 mile. Temp down to 11 F. Today is 55 degrees colder than yesterday. Band looks to be moving north but hope not!

[Chinook]

Bands of snow are getting much heavier here. I just went some 5 or 6 miles in town, and some of it was light snow, some was heavy! We have had snow since before sunrise, but it only accumulated in 1/4" bits and pieces. The snow depth on the grass might be 1.5".

[mayjawintastawm]

roughly 3" total, given some settling during the course of the day. Was real heavy right around 9 PM, easily 1" per hour if not double that, but only for 20 minutes or so... now tapering. Would have been nice to have that rate all night. Kind of a nice surprise!

[raindancewx]

Weird graupel / sleet mix down here where I live. I've only seen sleet/slop like this a couple times here, its almost always a clean transition from rain to snow at night. Areas just east of me likely went to snow, as they are a touch higher, while areas closer to the valley floor probably stayed all rain. Another band may try to come in later, would be snow.

[Chinook]

My area got 4-5" of snow, and the temperature went from 67 on Sunday afternoon to 0 this morning.

[ValpoVike]

4" up here.  Woke up to a frosty -7F.

 

[Chinook]

GFS/Canadian are showing some snow for the mountains this week, and a low pressure developing in Kansas on Saturday. At the moment, it looks like the Front Range cities will not be too snowy over the weekend, but this may be another decent storm for Nebraska.

[raindancewx]

We're on the board now - 0.3" snow at the airport today. February 1 was 67F here. Kind of amazing that the month is down to 58.2F now for the high, and should keep dropping. Some of the mountain ranges here have recovered somewhat, the mountains south of the CO border are near 45% of normal snow-water equivalent now.

I converted the SSTs from the extended data to ERSST V.5 (the 1950-now data) using the time when both data is available...and 1933-34 looks very similar to right now for February. It is interesting seeing that, since by highs and precipitation for each month of winter, it looks like my second strongest match to this year since 1931-32. Last year nationally was pretty similar to 1931-32 (a lot of the records falling today in February are from Feb 1932). 

Last column is my look at whether conditions in Dec-Feb by month were similar to this year compared to all years since 1931-32. Top ten close years get the Y. MH TX is a year following TX getting smoked by a land-falling major hurricane. March is ABQ precipitation. My estimate is higher after lowering for lower solar conditions, but adding more precip for lower SOI conditions.

[beavis1729]

Denver dropped 72 degrees in 48 hours (69 to -3) from 2/18 to 2/20.  Amazingly, this is only their 13th largest temperature drop over 48 hours in recorded history, going back to 1872.  The largest was 2/11 to 2/13 in 1951, when it dropped 80 degrees (73 to -7).

[ValpoVike]

An odd thing happened yesterday morning.  Temp was below zero, and I was driving my Jeep up Larimer County Road 43 with some steep switchbacks and a 400' fast elevation change.  When I got to the top, my back window shattered into a thousand pieces.  Someone suggested that it could be a result of the combination of temp and pressure change...does that sound like a viable theory?

[mayjawintastawm]

Not pressure (inside=outside, unless you're on a plane) but temperature + vibration. Sorry to hear! We moved houses about 6 years ago in January when the temp was -10, and I bumped our glass top table... same thing happened. Was pretty, for a minute.

[mayjawintastawm]

Strange winter so far. Cherry Creek Reservoir was not completely frozen over till 12/26- a good 10 days later than typical- and ice-out was just about 2/1, really early. Spring birds were starting to come back. It was completely ice free for at least 10 days. Now with the cold the last 5 days, it's completely frozen over again. Never seen this happen twice in one winter! Glad I am not a migratory bird this year.

[Chinook]

Synoptically, this storm on Saturday -almost- has the right stuff for a decent 3-6" storm for Denver, but it just won't be a 6" storm. 1-3" is a possibility for parts of our area from Denver to Fort Collins.

[raindancewx]

Super-torch week should verify my forecast for most of the East, its more or less destroyed the cold-anomalies for the winter. Annoyed the super cold over the Great Basin took this long to return, it was there in late September, late November/early December, so I thought it'd be back a bit sooner. Kind of impressive seeing FL back to +9 or whatever this month after having a fairly cold January too.

 

[Chinook]

My place has had a cold and snowy week. My best estimation was 4.7" for Monday, then 2.5" of fluffy snow in about 3 hours tonight. The temperature never got above freezing in 5 days! It's a real arctic blast, compared to our average high of 48 degrees.

[raindancewx]

2/24 should be the 67th frost since October 1st down here, pretty nice recovery after only having two through 11/30, the record fewest. We can surpass the entirety of the 2016-17 season for frosts (69) this week if the cold verifies as forecast, with however many frosts we get in March/April. If we stay dry, should continue to get a fair number. If March is colder than last year (pretty likely given the super-torch last year) we probably get more from that too.

The SOI has begun a massive upward correction these past few days, 2/1 to 2/24 is now at -11.4. As recently as three days ago it was -15.9. Odds peaked at around a 65% chance of a 20 point drop from January, but with the correction lately, its not going to happen, it back down to like 14%. If these +20 to +25 readings continue, the month will finish around -7. My hunch is one of days will see somewhat pressure at Darwin, but its still probably going to finish in the -6 to -10 zone now. Still "El Nino-ish". 

I guess the good news is that March 1986 had somewhat similar SSTs in Nino 3.4 with low solar, a big MJO wave...but a -12 SOI. Now that the SOI has come up, that year doesn't look as strong, with the Atlantic and Nino 1.2 a ways off too. It was very hot in March 1986 nationally.

[raindancewx]

The CFS has been correcting warmer for the SE and NW as March approaches. Somewhat unusual, as it usually sees warmth and then sees cold at the last minute.

I've been trying to come up with a blend of conditions that has a warm N. Pacific, a very cold Nino 1.2 in February (25.1C), cold Nino 3.4 (25.5C) and a -SOI (-7) for February, and a warm N. Atlantic, with low solar conditions but its pretty difficult. The Canadian will be out on 2/28. and it tends to do a better job than the CFS for the month ahead. The 1/31 Canadian had me around +6 for February, CFS was +9. It should be +3 to +4, so the Canadian kicked ass.

[Chinook]

We are in the midst of a snowy period for the West (mainly toward the West Coast) but the improvements in California won't really show up on this map. Here is a basin-snowpack comparison of Dec 14 and Feb 28. The improvements in UT and CO are pretty good, for the south parts of these states. There have been improvements (or too much snow) for MT, ID, WA, and part of OR. Unfortunately, there are still quite a few red colors on the map

[raindancewx]

The SOI crash definitely helped out down here, it finished at -7.7 for February, pretty impressive for a healthy La Nina. The Canadian has a very dry March for all of Colorado. I don't think I buy that. The numbers for S. AZ/S. NM should go up again tomorrow, with the snow that came through today.

The CFS & Canadian both have a warm March for the SW, although would be much colder than last year. 

To be fair, the Canadian & CFS precipitation forecasts for February both stunk.

March after a -SOI February is a strong indicator of a March less than +4F here (30/31 cases) once the SOI is -4 or so, but no guarantee of cold or even average conditions. I think a blend of the Canadian & CFS is probably about right for the US for temperatures. It looks like my Spring Forecast analogs for March (1968, 1975, 1986, 1999, 2006, 2008, 2012) except colder in Montana and with the cold in the NW instead of N. California. The assumption from Feb 10 for the analog blend was that the MJO wave would be around the 2-3 transition around 3/4, which looks like an OK call. That could mean that the torchy phases for MT/ND are reached by 3/31, if the wave continues. Phase 3 is fairly warm in the NW actually.

The analogs attempted to blend in the MJO wave, observed US conditions, and SST/Solar conditions. The lack of 70F highs here yet, through at least early-March tends to be a good sign of non-torchy March too, especially with the lows still frequently below freezing, it rarely warms up over 35F from the morning mins. I don't really think either model is right on precipitation, I think it starts off stormy in the East, and then some storms dig into the SW from 3/7 to 3/20 or so. It tends to be wet in March in the West south & east of a line from San Francisco to Cheyenne when the SOI is negative in February.

 

[Chinook]

The northern Plains will get their version of the "March Lion," in reference to the thread from the GL/OV subforum. The consensus of models is rain changing to snow or just snow in the northern Plains. 3" in northern Nebraska to 15" near the US/Canada border. The 12z GFS has 27" at the US/Canada border on Mon/Tue.  Areas in Colorado should be windy (like maybe wind advisory/warning for my area.) with cooling temperatures.

[raindancewx]

Curious to see what happens later this month now that the MJO wave is finally dying. It looks like it entered phase 3 on 3/1 or 3/2, but will be dead by 3/5.

Nino 1.2 somewhat warm relative to a colder Nino 3.4 is the pattern for last year, when it was very wet in much of the West in January 2017. Would be fun to see that in March.

Reasonably happy with how my winter outlook went for the US, although I was too cold in the West since I included 1932-33 as a hedge against a volcanic eruption. The dry West/wet East more or less worked out as planned though. Had most places w/in 3F of 1951-2010 high temperature means, which looks fine in most places.

I went with a pretty dry/warm Spring down here, after a brief wet period in mid-March, so we'll see how that works out. Once the SOI is under -4 or so in February, we never have "super torch" Marches, of 65F or more, so that would be nice, would be much colder than last year (+8) even if we still end up +2 or something.

[finnster]

5 hours ago, raindancewx said:

Curious to see what happens later this month now that the MJO wave is finally dying. It looks like it entered phase 3 on 3/1 or 3/2, but will be dead by 3/5.

Nino 1.2 somewhat warm relative to a colder Nino 3.4 is the pattern for last year, when it was very wet in much of the West in January 2017. Would be fun to see that in March.

Reasonably happy with how my winter outlook went for the US, although I was too cold in the West since I included 1932-33 as a hedge against a volcanic eruption. The dry West/wet East more or less worked out as planned though. Had most places w/in 3F of 1951-2010 high temperature means, which looks fine in most places.

I went with a pretty dry/warm Spring down here, after a brief wet period in mid-March, so we'll see how that works out. Once the SOI is under -4 or so in February, we never have "super torch" Marches, of 65F or more, so that would be nice, would be much colder than last year (+8) even if we still end up +2 or something.

Congrats on how your winter outlook went for the US, I just regret that the west (particularly SW) had yet another dry/warm winter.  Man, a dry/warm spring in the SW is exactly what ISN'T needed.  February ended up being a decent month for snow (and some cold) in northern CO - however if your warm/dry outlook for the west/SW is right it will have been for naught.  I'm already getting nervous about March here on the CO front range - today was about 65 degrees with strong winds and 10% humidity. Dries things out fast.  March used to be a very reliable snow month on the northern front range.  Now no storms in sight

Anyway, hope you in NM at least get some much needed moisture in March.