raindancewx

Looking back at last year, we did pretty well for snow once the MJO reached the phase 2/3 transition around 2/28. For the high amplitude portion of the ongoing MJO wave, the cycles have been +49 to +55 days for phases 3,4,5,6,7 repeating, with a tendency toward the longer part of the cycle lately. Last year the MJO wave got to phase 2 on 1/21 and then 2/20 (+30 days), and then entered phase 3 on 1/26 before returning 2/28 (+33 days). Given the +55 days cycle lately, the MJO should reach phase 8 around February 14th, sooner if the Euro is wrong about the slight retrogression towards phase 6 for a day or two. Phase one is then around Feb 22nd. Phase one is our strongest wet phase in February. We entered phase three with current wave on 11/26 and then 1/14, so unless the wave dies or increases massively, its probably week one or week two of March. Phase 3 Entrance: Nov 26/Jan 14 (+49) Phase 4 Entrance: Nov 29/Jan 17 (+49) Phase 5 Entrance: Dec 1 /Jan 22 (+52) Phase 6 Entrance: Dec 5 /Jan 27 (+53) Phase 7 Entrance: Dec 8 /Feb 1 (+55) Phase 8 Entrance: Dec 20/ Feb 14 (+/-2 days?) Euro has 2/15 but its been underestimating the MJO amplitude for the last week. Real question at this point is when the wave dies. If it returns to the warm phases coherently in late March, the East will roast again.

Looking back at the Dec-Jan in the US since 1930 after a major hurricane hit Texas, would say 1980-81 is the closest. That year was a hot winter here, then it was wet in March. Dec-Jan 1932, 1941, 1988, 1961, 1967 are all too cold in the West, off in the East too after a major hurricane hit Texas. 1957/1933/1999 are generally too warm everywhere after a major hurricane hits TX. 1942/1970 have other issues. 1983 is too cold everywhere. That leaves 1980-81, which is like an over-amplified version of this year. The 1980-81 Dec-Jan period had a warm Northern plains, warm West, cold East Coast, cold S. TX, cold South. That's the correct pattern. It doesn't work at all for SSTs in the tropics, but 1980 (x3), 1983 (x2), 1999 (x1), 2002 (x2), 2014 (x1), 2016 (x1) produces the right kind of look for Dec-Jan nationally. A look that is correct for SSTs and Dec-Jan would be 1944 (x1), 1977 (x1), 1980 (x2), 1983 (x3), 1999 (x1), 2002 (x3), 2005 (x4), 2010 (x2). Not many areas of the US more than 3F below 1951-2010 average for high temperatures. The blend of the two maps would be around an ~85% match nationally I think.

The Canadian has the mother of all Western torches for February, particularly for Arizona and parts of Texas. I don't think the magnitude is right, but that's not too dissimilar spatially from what I expect for February. I'd be +6F on the map below, v. the +9F the CFS has.

Somewhat cold winter for the East so far against 1981-2010, but S. TX is the current winner by anomalies. My outlook was against 1951-2010 mean highs, which are somewhat colder, so I think a lot of areas in the NE will actually w/in 1F against 1951-2010 highs for Dec-Jan. Had the Dakotas warm. Misses are the dryness in the Midwest and the heat in the West so far. I think against 1951-2010, the departures look something like this -

The SOI spike from -2.6 in December to +10.0 or so in January is fairly rare. If you use SOI analogs that are +/-4 for each month only similar winters are: 1934-35, 1936-37, 1985-86, 2005-06, 2013-14 Not exactly cold here, but only +2F in February, and then a normal March. Possibility of heavy rain and/or snow in Feb/Mar, and then May/Jun.

My Spring analogs have a February look that is like a less extreme version of November...but I think something like this is more likely given where the MJO is - These are my preliminary Spring analogs. The MJO will be in phase 6-7 at the start of February looks like, so the map probably looks like the second map for the East in February, but looks more like the first map after Feb 5 or Feb 10, maybe through early March. The Spring analogs are a blend of MJO expectations, Ninas that were coldest east of 120W in NDJ, low-solar, and rare conditions locally (super dry since Oct 1, warm in Nov-Dec, etc).

My dream MJO scenario at this point is the red path. Would be pretty shocked at this point if we got the yellow path. I'm not a huge fan of 2006 as an analog for January on the MJO or for the subsurface, but if we migrate it at this amplitude, and the warmth stays in the subsurface below the Nina, we're going to do some major Nina damage too. The MJO went through phase 3-4-5-6-7 in Jan 2006, similar to this year, which is 2-3-4-5-6 in January. Less anomalous subsurface heat/cold v. 2006

It is amazing how non-canonical this La Nina is to date. I know since the 23rd, the cold anomalies in the East have burned off more, I checked Philly, they're back to -1.5F for January, with some days coming near 60F by the end of the month. I'm down to +2.5F or so for January, as the nights have been pretty cold with less than 0.1" of precipitation September 30th. My winter outlook is doing pretty well for Western precip, I had the Northern Rockies slightly wet and a small area of wetness near Vegas/Los Angeles, which may verify, they're average so far from the one big storm earlier in January. Had the Midwest wet...yet to verify. Everyone else dry. Had the East +0 to +2F for winter against 1951-2010, which doesn't look terrible given the current thaw, I think Philly is -1.4F winter to date against 1981-2010, assuming its closer to -1F or less against 1951-2010. I threw 1932-33 in on the chance Agung erupted as a VEI 5, since 1932-33 was a volcanic winter, but it made my outlook for the West 2-3F too cold everywhere. Texas, Arkansas and Maine the only places nationally that are cold AND wetter than normal to date. Dakotas and Northern California were the winners last year.

Looking highly likely at this point that Albuquerque finishes November-January with 0.03" precipitation, the lowest figure for that period 1931-32 to now. Been working on a Spring outlook (will link it here in two-three weeks when all the data is in), and it is looking pretty warm/dry here for most of Spring. 1) When Nov-Jan is dry here, following May is almost always dry (9/10 driest Nov-Jan followed by a dry May, in all other years, 38% shot at a wet May). 2) We've had two wet Aprils in a row, in ten other instances of that happening (or close calls), only one of the following Aprils was wet. 3) Dry Nov-Jan periods do heavily favor a wet June, an inch of rain in June or more is 5x more likely after a dry Nov-Jan here. I have other methods for predicting precipitation that like June too. June is a strong indicator of the following winter here, you can virtually (94%) rule out a cold winter here if June is >=92F for the high. Wet Junes (>=0.6") are under 92F 97% of the time here. The MJO implies we have a shot at some major precipitation in February or March, as do some of my precipitation and temperature replication techniques - after that, I think we get almost jack until June. The CFS seems to be trying to move toward a wet February and/or March in the SW? Also, the Monsoon is (weakly) linked to three factors here - annualized sunspots, precipitation Nov-Apr before Summer, PDO values Nov-Apr before Summer. The ideal Monsoon years, like 2006, tend to have a low, low, positive blend on the three factors. Pending any sudden PDO or precipitation changes, this kind of looks like a strong Monsoon year, at least conceptually. For now, a blend of 1934, 1934, 1943, 1994, 2006, 2010, 2010 looks about right. Last year the PDO was more favorable, but we had a lot of precipitation in Nov-Apr before Summer. On balance, this year looks better.

February looks like a wild month to me - couldn't find any years where the MJO goes (roughly) through phase 2-6 in January at high amplitude and then stays very active through February, which looks possible. 1978 & 1990 are better analogs in Feb than now if the amplitude stays high. Since the 70s the high amplitude January years crash and the low amplitude January years tend to see increased magnitude in February.

I was checking some of the conditions in the East, looks like Philly is now within 2F or normal month to date with the 23rd included, with some warm days ahead yet and the West's heat will gradually shrink as well. I had the East warm in January and the West cold in January - that looks pretty bad for actual January, but its probably just going to be two weeks early in the end. Although the East will probably be mostly within 2F or normal by the end of the month. Jacksonville is within 3.5F of their normal, when the 23rd is included. My lows are running 2.5F lower than last year to date, with the dryness more than offsetting the somewhat warmer highs (+2.3F) so far.

Will be interesting to see how some of my pet theories play out in March. Nino 1.2 & Nino 3.4 conditions can be re-created for Nov-Jan using two sets of analogs (will change if Nino 1.2 or 3.4 warms rapidly this week). Major Hurricanes Hitting TX Analogs: 1967, 1970, 1980, 1999. OR Low Solar Analogs: 1934, 1934, 1934, 1964, 2007, 2007. First blend and second blend are each at -0.80C and -1.10C in Nino 3.4 and Nino 1.2 respectively, against 1951-2000 data according to this data, which is what NDJ looks like to me. https://www.esrl.noaa.gov/psd/gcos_wgsp/Timeseries/Data/nino12.long.anom.data (change 12 to 34 for Nino 3.4) First blend has high solar activity (opposite to now), but features years after a major hurricane (correct) hit Texas. Second blend has low solar activity (correct), but features years without a major hurricane (opposite to now) hitting Texas. I couldn't re-create the NDJ conditions in Nino 3.4 and Nino 1.2 with low-solar condition AND a major hurricane hitting Texas. The first set of years is pretty wet in March, second set is quite dry. So, I went to tie breakers - The first set of years is very wet in August+October, a good indicator of a wet March - we were dry those months this year. The second set of years is dry in those years. However, August + Sept 27-Oct 26 was very wet in 2017 (2.2" Sept 27-30 here) like the major hurricane years, but the non-major hurricane years were very dry in that period.

Looking through the MJO forecasts and comparing them with history, not a lot of January MJO propagation like this year, when factoring in phase and magnitude. I like January 1986 best, easily the closest propagation with 2-3-4-5-6-7 observed, we began in two this year. Doesn't appear we'll have any neutral MJO conditions in January. The magnitude in 1986 was greater than this year though. January 1978, 1989, 1990 are decent. I'd go 1986 x7, the others x1 each. 1988/1989 start in 1 and 3, but blended together, they start in two at lower magnitude than 1986. 1977 started in neutral, so its behind. Timing is closest to 1989/1986, but the MJO has been moving through the phases about a week later overall. Black line is January observed MJO conditions. Red line that I drew is the Euro forecast for the rest of January 2018. February 1986 is one of my all-time snowy months, and very wet too - would be nice to get it. City had 10.2" snow I believe, near the end of the month. Here is December 2017, v. the MJO blend I outlined above, plus one week.

The 3 km-NAM is honestly awesome at short range - it had essentially no rain/snow for the city and that seems to be verifying other than 20 minutes of trace-level rain. Euro and GFS both had much more, with some snow. Will be impressed if we end up with even 0.01" from this event in the city. On to the next storm I suppose. The non-Nino winters here after major hurricanes hitting TX lean heavily toward dry January, and we're ~2/3 through with 0.03". Not sure why the local NWS kept the weather advisory for the city for this event, it was 52F at 10 pm when they renewed it. My rule is <50F on a warm day by 10 pm if it is to convert to snow over night.

The GFS, Euro, 3-km NAM show a fairly healthy line of showers associated with a Pacific cold front moving through NM, bringing rain and then maybe snow even to valley locations. Going to have to be one incredible cold front if we go from 55-60F on Saturday to snow by Saturday Night, although it does happen. GFS thinks 0.10-0.20", Euro and 3-km NAM think 0.05" or so. I'd expect 0.05"-0.10" precipitation, with up to the final third of it as snow...0.1"-0.5" in the city?

^^ A lot of time they will ignore the lowest low or highest high if it only lasts for five minutes. Don't know if it is rounding, an error, or some kind of calibration.

MJO is now coherently just barely in phase four, many models have it in phase five in a week or less. Snap to a much warmer pattern for the US east of the Rockies should be coming. Will be interesting to see how much of this gets wiped out - Areas of North Dakota were +2 to +4 in December, so a wipe out of the (relatively) minor cold anomalies in January there would put them near normal, not cold for winter. Suspect the blue and purple areas on the map have a colder than normal month, I think the green areas end up near average though. Those reds in the West should trend down too. Would expect most areas to be +8 to -8 by the end of the month instead of +12 to -12. Even here, largely without precipitation, it looks much colder than December now. West Texas is fairly cold in phase five, so don't think the cold is particularly threatened in Texas.

I'll repeat my earlier complaint - its amazing that Monterrey, Brownsville, Houston, New Orleans, Savannah, Charleston, San Antonio and other cites have had snow this winter while it has barely rained here since September. The good news is...it is very cold today. So that's nice. I will say: One of my analogs, 1943, had multiple snow events into the deep South and TX, like down to the Gulf Coast, so that is actually verifying pretty well. You had a super warm Atlantic, neutral PDO, low solar activity, and an east-based "cold Neutral" look to ENSO that year. 1943 is like a colder version of 2008 nationally. Even the warm patch of waters north of the cold Nino 3/1.2 existed in 1943-44.

I have a theory that certain events repeat at relatively equal levels of sunlight, so been starting to look for some kind of "Harvey" effect in Spring 2018, since it hit in late August. To me, there are 59-non El Ninos for the 1931-32 to 2016-17 July-June years, if you separate out the ten non-El Nino years in that time-frame when TX was hit by a major hurricane from the remaining 49 years, one of the effects that pops out is a higher than normal chance of a very wet March in the Southwest: >=0.8" in non-El Nino, MH years in ABQ: 3/10 Marches >=0.8" in non-El Nino, other years in ABQ: 4/49 Marches You can say pretty safely that a "very wet" March is more likely in a non-El Nino after a Major Hurricane hits Texas. If you did it for >=1", its 2/10 v. 1/49 - quite literally 10x more likely than usual. https://mathcracker.com/z-test-for-two-proportions.php#results

It's kind of amusing see TX as one of the big winners for precipitation this winter - we're not even remotely close to Nina climatology at this point (40/90 days in). I know here, I should have ~0.63" for Dec 1-Jan 11 using 1951-2010, probably more using 1981-2010, so I'd say -0.5mm/day is about right here. The wet NW idea has absolutely not verified this winter, outside Montana.

My horrible dry streak was ended this morning - we got 0.03" of an inch of rain. First measurable precipitation since October 5, 2017, before we even knew who had a shot at the World Series or that there would be new tax policy for everyone. Flagstaff's snow-free streak ended last night as well, and they got ~1/6 of their winter precipitation in about six hours, now at 50% of normal precip out there.

I was playing with the observed SSTs in December for Nino 3.4 and Nino 1.2. Fairly strong correlations between Dec & the following March-May periods. I normalized the March-May periods against 1951-2010 means. The conversion factors from December SSTs to MAM work out to -0.27C in Nino 3.4 for MAM, and -0.37C for Nino 1.2 in MAM. That configuration can be replicated with SSTs for MAM 1961, 1981, 1981, 1984, 2006. The configuration is based on correlations, which means they'll probably be off somewhat. To offset that, I ran 13 cases, where Nino 3.4 / Nino 1.2 come in near but not exactly at -0.27C and -0.37C. I then looked at subsurface conditions, and weighted each of the 13 scenarios at 1,2,5,10,15,25 points. I re-produced all 13 scenarios using historical years with similar conditions, and then looked at the years that appeared most frequently in the higher weighted scenarios. Given the subsurface looks like this, I assumed Nino 1.2 was more likely to come in colder than the correlation implies, while Nino 3.4 was more likely to come in warmer than the correlation implies. The scenarios that had Nino 1.2 warming massively relative to the correlation were thus weighted less, as were the scenarios that had Nino 3.4 cooling massively relative to the correlation. Cases MAM Risks Points Scenario 3.4 1.2 % 1 -0.67 -0.37 5% 2 -0.47 -0.37 5% 3 -0.27 -0.37 25% 4 -0.07 -0.37 15% 5 0.13 -0.37 10% 6 -0.27 -0.77 10% 7 -0.27 -0.57 15% 8 -0.27 -0.17 5% 9 -0.27 0.03 5% 10 -0.67 -0.77 1% 11 -0.47 -0.57 2% 12 -0.07 -0.17 1% 13 0.13 0.03 1% Using those weights, I then did one final filter, adding three points to low solar years, and subtracting three points from high solar years for March-May to help sort out ties for weighting. A fair number of El Nino winters that were rapidly transitioning to La Ninas came up, will be interesting to see if we have the reverse of that. Anyway, the top 12 Springs were: 2006 (x4), 1984 (x3), 1981 (x3), 1961 (x2), 1977 (x1), 1963 (x1), 1986 (x1), 1978 (x1), 1988 (x1), 1960 (x1), 1973 (x1), 2003 (x1) That blend is relatively close to what has happened in December, especially if you use Dec 8 - Jan 6 as December. The long and the short of this is, the weighted blend is pretty wet for me in March, which hasn't happened since 2007. With my weights, solar factors, etc, the ONI would be -0.19C for Nino 3.4 in MAM, and -0.46C in MAM in Nino 1.2 Given the subsurface conditions, and the match to Dec 8 - Jan 6, plus my various simulations, fairly confident the map will look like below in MAM.

The period for mid-Dec to mid-Jan will obviously be colder for the US, but for December itself, not really a cold month nationally. With a couple of modifications, December 1980 was a good match. I threw in 1943 & 2011 to make the Upper Midwest warmer, and 2012 to make the SE/NE warmer. You have "less" of a break in the heat in my analogs than this year in a couple spots (NW, SE, TX) but its close nonetheless.

The European, NAM, and GFS all have valley rain and mountain snow for NM this week. Tues/Weds cold see the end to the absurdly long stretch of days without precipitation. Would be a good snow event if the European verifies.

The dewpoint has skyrocketed, all the way back to 30F...from 3 this time last night...but not looking like we'll get any measurable rain overnight. Close though, only missed by 20 miles or so. Of course...its 48 at 3 am as a result. Will be up to the next storm to break the dry-streak sometime Tuesday night into Wednesday.