raindancewx

The Nate Mantua/JISAO PDO isn't in yet, but the NOAA version of it is, and shows a big crash for January. The JISAO PDO usually moves in a similar way to the NOAA PDO, but with higher values. https://www.ncdc.noaa.gov/teleconnections/pdo/ 201910 -0.96 201911 -0.28 201912 0.01 202001 -1.17

The Euro & GFS both have a lot of snow over the next 5-10 days for New Mexico & Colorado, virtually all of both states will see snow if they are right. This is through 11 am Tuesday on the 12Z Euro and 18Z GFS.

General idea for Spring for our region is 1954, 1993, 2005, 2019 as a blend, but a bit warmer then the raw blend. For March, 1954, 2004, 2005 is the right idea.

This is all roughly in my (nearly complete) Spring forecast...but - The basic idea for me for March is that it should loosely resemble the mid-Nov to mid-Dec period. So starts out cold in the East, then warms up. I've been using 3.5 months (~107 days) as the estimate for this, but lately it's been more like 102 days. There are fairly strong indications for March that warmth will return to the West, but I think the subtropical jet will be shifted into the SW (NM/AZ) at times too, with a lot of moisture. Not every month here gets precipitation, but every time October is wetter than September, it has rained/snowed the following March (37/37) - we had that last year, and this year. September long-term is a much wetter month here than October - so it's a useful indicator, and statistically significant (far more likely to get heavy precipitation in March if Oct>Sept). ~Nov 16-Dec 15 is the March idea. An analog blend that looks similar to that nationally is March 1954, 2004, 2005. We had roughly 3.5x normal precipitation in that period - so the systems that come through should be somewhat different than in recent months if that repeats. See the resemblance? That pattern of dryness from TX to Detroit in December is actually pretty hard to re-create with similar ocean/solar conditions. For the West, a big -NAO in October like 2019 is a warm signal for the West. A big +AO in Jan/Feb is also a pretty strong warm signal for the SW in March. All that being said, Nino 3.4 not cooling during Spring when it is warm is more like a weakening La Nina than an weakening El Nino, and is similar to last year. So that favors cold shots eventually pushing out the Western warmth later in Spring. I'm still toying with it, but I think April might be incredibly warm nationally, despite the correlations shown below, I'm talking like 2/3 of the lower 48, at +4 to +8 or something. January/April usually have common tendencies nationally, and January is the most different period of the Oct-Feb cold season so far, no all-time record cold for the North this year in H2 January. At a lead time of a year, Nino 3.4, which was 9th warmest since 1950 last March, is also a pretty strong cold signal for the Northeast, and the deepest blue area shows up as cold in my blend for March. You can also see the hints of dryness across the South.

Looking at the Northeast records, it actually is pretty rare to get four snowy Marches in a row. Boston-NYC-Philly look like they were above normal in March 2017, 2018, 2019. So you'd have to bet against it for 2020. Will be interesting to see how that plays out, since the NAO indicator does still support a somewhat -NAO for March.

If an El Nino is to develop again for winter 2020-21, that's pretty rare historically. Only cases I know of for a 27C or warmer Nino 3.4, three times in a row, in the past 100 years: 1939-40, 1940-41, 1941-42 2002-03, 2003-04, 2004-05 (and here you have to fudge 2003-04 - it's right at like 26.96C or so). The early 1990s are kind of an interesting case, since 1992-93 was not 27.0C, but came after a volcanic eruption that cooled the Earth, and so you had essentially an El Nino without Nino 3.4 warm in 1992-93.

The legendary Halloween 2019 cold dump in the West, +3.5 months is starting to show up in non-bs range modeling. Pattern change starts after that, ala November 2019. Got to 21F at my place on Halloween morning - record cold. Should be about a 20-25 day window for the NE, for 2/20 to 3/10 or something. Heat begins to build rapidly after that, like mid-Dec to mid-Jan. Cold today was impressive out here too - 39th coldest day in February in 100 years (2,825 days). One difference from last year is that the severity of the cold isn't the same in Billings or other spots near Canada. Billings had it's second coldest month in ~90 years last February, with 10 days that were 30-40 degrees below average in a 28 day month.

The all-time record cold that entered the West is likely to return mid-month, at the 3.5 month lag. This is on the NWS Billings site - this is theoretically the Halloween cold shot.

On the final update, only 0.8" snow yesterday in Albuquerque. Today's high of 32F with a low of 12F in Albuquerque is the 39th coldest day in February in the last 100 years. Close to the 99th Percentile for cold in that period. I think we may make a run for 5-10F in the morning, which is pretty impressive here for February. I think the all time record low is about -7 for February, matched in 2011. Dew point is "only" -5, so we won't break the record.

CPC just had a baby everybody. Guess what gender? https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/ensostuff/detrend.nino34.ascii.txt 2019 10 27.20 26.75 0.45 2019 11 27.23 26.75 0.48 2019 12 27.12 26.65 0.47 2020 1 27.18 26.45 0.73 (near identical to last year) 2018 10 27.62 26.75 0.86 2018 11 27.61 26.75 0.86 2018 12 27.49 26.65 0.84 2019 1 27.20 26.45 0.75 Year DJF JFM FMA MAM AMJ MJJ JJA JAS ASO SON OND NDJ 2010 1.5 1.3 0.9 0.4 -0.1 -0.6 -1.0 -1.4 -1.6 -1.7 -1.7 -1.6 2011 -1.4 -1.1 -0.8 -0.6 -0.5 -0.4 -0.5 -0.7 -0.9 -1.1 -1.1 -1.0 2012 -0.8 -0.6 -0.5 -0.4 -0.2 0.1 0.3 0.3 0.3 0.2 0.0 -0.2 2013 -0.4 -0.3 -0.2 -0.2 -0.3 -0.3 -0.4 -0.4 -0.3 -0.2 -0.2 -0.3 2014 -0.4 -0.4 -0.2 0.1 0.3 0.2 0.1 0.0 0.2 0.4 0.6 0.7 2015 0.6 0.6 0.6 0.8 1.0 1.2 1.5 1.8 2.1 2.4 2.5 2.6 2016 2.5 2.2 1.7 1.0 0.5 0.0 -0.3 -0.6 -0.7 -0.7 -0.7 -0.6 2017 -0.3 -0.1 0.1 0.3 0.4 0.4 0.2 -0.1 -0.4 -0.7 -0.9 -1.0 2018 -0.9 -0.8 -0.6 -0.4 -0.1 0.1 0.1 0.2 0.4 0.7 0.9 0.8 2019 0.8 0.8 0.8 0.7 0.6 0.5 0.3 0.1 0.1 0.3 0.5 0.6

Three in a row?

I'm at 10.3" inches of snow at my place so far for Oct-Feb. Airport got 1.3" today - so they're up to 6.6". If we get more snow this month before the NE corridor does, Albuquerque will probably be ahead of the combined NYC + Philly + Baltimore + DC total again - currently 4.8+0.3+1.8+0.6 - which is 7.5". Those four cities get ~80 inches of snow in average year (25+22+18+15), about 8x Albuquerque, so it's kind of nuts how close the totals are.

Albuquerque finally had a "high ratio" snow event today - airport reported 0.05" liquid equivalent as 1.3 inches of snow. So 6.6 inches for Oct 1-Feb 4 at the official site. At my place, only 0.7 inches today, but up to 10.3 inches for the season. Roughly 40% of precipitation to fall in Dec-Feb so far has been snow for Albuquerque, and then another ~22% of the precipitation in November, the wettest November in 100+ years was also snow.

My NAO indicator is still on track. Blending years with a similar Sep-Mar, and May-Apr transition to match current year conditions is a good indicator. March is the period to watch.

Some new data this week. The QBO has gone negative. 2004 -4.84 2.61 5.45 10.46 12.97 11.75 9.96 8.74 7.29 8.00 4.35 2.45 2005 -0.69 -0.96 -0.33 -6.64 -15.09 -20.59 -24.20 -25.87 -27.80 -28.76 -29.55 -25.04 2019 9.02 9.25 11.82 13.36 14.59 14.36 10.96 9.97 8.25 7.27 5.07 1.66 2020 -2.51 -999.00 -999.00 -999.00 -999.00 -999.00 -999.00 -999.00 -999.00 -999.00 -999.00 -999.00 No new ONI value yet from CPC - likely tomorrow or later in the week. Solar activity may be coming up now - January had more than six sunspots, down from last January but up from recent months. The El Nino is having a secondary peak, like last year. Warming of >0.3C from Jan-Feb in Nino 3.4 is more like a La Nina that is weakening than an El Nino, which is why February is expected to be similar to last year (warm East, cold West). Nino1+2 Nino3 Nino34 Nino4 Week SST SSTA SST SSTA SST SSTA SST SSTA 04DEC2019 22.5 0.1 25.3 0.2 26.9 0.3 29.4 0.9 11DEC2019 23.1 0.5 25.5 0.4 27.1 0.5 29.5 1.0 18DEC2019 23.3 0.4 25.5 0.3 27.2 0.6 29.5 1.1 25DEC2019 23.6 0.3 25.5 0.2 27.0 0.4 29.5 1.0 01JAN2020 23.7 0.1 25.7 0.3 27.2 0.7 29.6 1.2 08JAN2020 24.3 0.2 25.9 0.4 27.1 0.5 29.3 1.0 15JAN2020 24.2-0.2 25.6-0.1 27.0 0.4 29.2 0.9 22JAN2020 24.6-0.2 25.8 0.0 26.9 0.3 29.1 0.9 29JAN2020 25.3 0.2 26.1 0.2 27.4 0.8 29.3 1.1 The new Canadian run still shows a La Nina developing in Summer but it is much slower to form that on the last run. The subsurface implies to me a final peak Feb or Mar or both, then rapid cooling at the subsurface. The record setting (?) +AO for February forecast is a pretty strong warm signal for Feb-Mar...and then not at all in April.

I had Boston and most of New England near average (40" in Boston from the blend) for snow - that still looks OK to me, but the NYC to DC corridor that I had above average, well above actually - does look like a bust to me. It's interesting actually since the other areas of the US that I had enhanced/or below average have been right - lot of snow Rockies, Plains, even the Midwest areas are basically right, and I had the mid-South below average too. My highs are forecast to be in the mid-30s next week, which is reminiscent of the mid-October cold shots we had out here, so the pattern still seems to be repeating at a general 3.5 month lag. The snow storm for Colorado in the coming days is fairly similar to the event around 10/20 I think, I'd have to look.

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?

CFS matches the spatial look you get matching the 100-180W zone's heat content in the Tropical Pacific. https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/ocean/index/heat_content_index.txt Heat content is now almost identical to last year in January. Was +0.59 in January 2019. The CFS 6-10, 8-14, and week 3-4 all show a warm February in the East. No update from the Canadian seasonal model yet on Tropical Tidbits. 100-180W Nov Dec Jan 2019 0.26 0.34 0.51 1980 0.35 0.61 0.36 1980 0.35 0.61 0.36 1992 -0.27 0.19 0.27 2001 0.22 0.17 0.95 2001 0.22 0.17 0.95 2003 0.54 0.17 0.05 Blend 0.24 0.32 0.49

I'm aware of the sensor thing you guys talk about. My thing is, Massachusetts looks warmer inland anyway, so I don't think it matters much, except for where the core of the heat has been in the Northeast? I use Boston as regional proxy.

The data for today is down currently, but through the first 60 days of winter, it looks like the fourth/fifth warmest winter for Boston in the past 100 years. Boston's lowest low for 10/1-01/29 is 14 degrees - 2nd warmest minimum for that period back to the 1870s. Finishing with only 16 lows 32F or less for January is kind of impressive too for Boston - fewest since 1932. My analogs had lows around +5F for New England, that may end up as the right idea for the winter. Currently +6.2F in Boston against the 1951-2010 average low for the first 60-days of winter. I think even out here in the desert, record warmth for average low in Dec-Jan is right around 30F.

Elephant Butte Lake is already the fullest it has been since 2010. Currently 585,967 acre feet of water in the lake. Last day with more than that? June 18, 2010 (586,945 acre feet). The highest value for 2010 was 604,248 acre feet, with 2009 peaking at 705,284 acre feet. I don't think we'll beat 2002 - which peaked at 905,744 acre feet. I'm expecting the lake to get into the 640,000-740,000 acre feet range sometime by the end of July.

I'm expecting a compromise between the 3.5 month lag timing analog for February (Oct 16-Nov 15), and similar US weather/solar/ocean/SOI conditions (1937, 1954, 1993, 1993, 2005, 2005, 2019). The top SOI blend for NDJ is likely 1936-37, 1992-93, 2004-05. US conditions in Dec/Jan look a lot like 1953-54, 1992-93, 2004-05, 2018-19. What does that compromise look like? This - and I warmed it up another 2F because not many areas of the US have snow cover right now. The CFS does seem to be heading in the right direction toward the cold Central idea. There have been hints on some of the methods I used for a pretty impressive cold dump into the West mid-month. That should bleed East, but run out of time to make the east cold by the 29th. That's my general idea. Most of the NE will probably catch up to near average during the transitions into/out of the warm pattern, but obviously, finishing below average is most likely for most NE zones.

I actually consider 1913-14 to be a very weak El Nino, like this year. The issue with 1959-60 is that it had near record high solar activity, very unlike this year. For solar, it seems like the equinoxes are the peak for precipitation effects, while the solstices are the peak for temperature effects, when I look at various US sites statistically. In other words...you'd expect different snow outcomes even in a similar temperature pattern to March 1960. I will say - March 1960 was about 27.0C in Nino 3.4. If this event collapses rapidly, that's not impossible. We're only at 27.0C or so in January. So you'd just need the ocean to not warm, or to warm less than usual from Jan-Mar in Nino 3.4.

Weather Trends 360 has a pretty good track record for seasonal forecasts - they have a much less snowy March for the NE corridor than last year. We'll see how that goes. I think the best window for NE snow is Feb 15-Mar 15, coinciding with the return of wet/cold/powerful storms into the SW, and some weak/transient blocking. We'll see. On their map, yellow is less snow than last year, and the blues are more snow than last year. The three red lines are >1", >6", and >12".

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.