raindancewx

On Tropical Tidbits, none of the four Nino zones are currently cold enough to be a La Nina. This is what has happened the past week:

The 990 mb low forecast over southern Kamchatka is pretty strong for mid-March. That's likely a pretty good storm 3/27-3/31. The storm forecast for this week was preceded by a 970 mb (!) low in that spot, +17 days, as you'd expect via the Bering Straight Rule.

Tada - right on time, 3/12-3/13.

This is the Euro. Mostly day 3.5-5.5 in real time now since this initialization is from 5 am this morning.

European has been showing La Nina ending in March. Still looks like that might be right. It's certainly interesting seeing Nino 1.2 and 3 warmer than 3.4 Nino1+2 Nino3 Nino34 Nino4 Week SST SSTA SST SSTA SST SSTA SST SSTA 06JAN2021 23.1-0.8 24.7-0.8 25.5-1.1 27.1-1.3 13JAN2021 24.0-0.3 24.7-0.9 25.4-1.2 27.0-1.3 20JAN2021 23.9-0.8 25.2-0.6 25.5-1.1 26.9-1.4 27JAN2021 24.6-0.5 25.7-0.2 25.9-0.7 27.1-1.1 03FEB2021 25.3-0.2 25.8-0.3 26.0-0.7 27.2-1.1 10FEB2021 25.4-0.5 25.4-0.9 25.5-1.2 27.0-1.2 17FEB2021 25.7-0.5 26.2-0.3 26.0-0.7 27.2-1.0 24FEB2021 25.2-1.1 25.7-0.9 25.7-1.2 27.2-1.0 03MAR2021 26.6 0.2 26.5-0.4 26.3-0.7 27.4-0.8

A lot of times in La Ninas, the Marches that end up fairly cold nationally precede El Ninos the following winter. Given that the SOI has been predominantly negative (El Nino-like) for almost two weeks now, really need to see if the SOI can sustain negative. March SOI is currently -6.1 almost 1/4 through March. Date Tahiti (hPa) Darwin (hPa) Daily Contribution 30 day Av. SOI 90 day Av. SOI 7 Mar 2021 1011.35 1007.95 -3.40 7.18 13.28 6 Mar 2021 1011.64 1008.10 -2.73 7.57 13.49 5 Mar 2021 1010.81 1008.15 -6.94 8.29 13.65 4 Mar 2021 1010.79 1008.45 -8.47 9.13 13.82 3 Mar 2021 1011.54 1008.70 -6.08 9.71 13.98 2 Mar 2021 1011.34 1008.65 -6.80 10.05 14.18 1 Mar 2021 1009.94 1007.60 -8.47 10.48 14.43 28 Feb 2021 1009.96 1006.35 -5.43 10.99 14.76 27 Feb 2021 1009.84 1004.80 1.44 11.47 15.13 26 Feb 2021 1007.90 1005.15 -9.56 12.12 15.33 25 Feb 2021 1008.06 1006.40 -14.79 13.45 15.45 24 Feb 2021 1010.22 1006.20 -3.46 14.79 15.65 Since 1990, cold-ENSO winters with a -SOI in March are 4/4 in going to El Ninos: 1996-97 to 1997-98, 2001-02 to 2002-03, 2008-09 to 2009-10, 2013-14 to 2014-15. The overall track-record from 1931 to 2019, if you include borderline El Ninos 1990-91 and 1979-80, is 10 of 18 cold-ENSO years with a -SOI in March go to El Nino or near-El Nino conditions the next winter. Cold ENSO (La Nina or cold-Neutral) winters with a -4 to -8 SOI in March: 2001-02 (-6, El Nino followed) 1996-97 (-7, El Nino followed) 1989-90 (-8, near-El Nino followed) 1983-84 (-6.5, La Nina followed, but 1984-85 is a very wet/cold winter in the SW) 1950-51 (-5.5, El Nino followed) 1937-38 (-4, La Nina followed, but 1938-39 is a very cold winter in the SW) Other Recent Cold ENSO, but -SOI Marches: 2013-14 (-12, El Nino followed) 2008-09 (-1, El Nino followed) 1985-86 (-0.3, El Nino followed) 1984-85 (-3, Neutral followed)

Late February to early March has actually been seeing a bunch of little lows moving to the southern tip of Kamchatka from NW to SE. Should be more systems in late March and early April moving in favorable paths for CO, NM, and WY. Fantasy range GFS has another 970 mb low south of Kamchatka on 3/17. My guess is that's the end of the sequence, and it would show up here around 4/3-4/7 if it verified.

That storm is likely real at least. It is in the 3/12-3/16 time frame I flagged in late February with the 970 mb low off southern Kamchatka.

CPC has re-calculated the NAO monthly data using 1991-2020 averages. Same for some of the other teleconnections. 1981-2010 Baseline: https://www.cpc.ncep.noaa.gov/products/precip/CWlink/pna/norm.nao.monthly.b5001.current.ascii.table (+NAO Feb 2021) 1991-2020 Baseline: https://psl.noaa.gov/data/correlation/nao.data (-NAO Feb 2021) This is 1981-2010: NAO Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 1950 0.92 0.40 -0.36 0.73 -0.59 -0.06 -1.26 -0.05 0.25 0.85 -1.26 -1.02 1951 0.08 0.70 -1.02 -0.22 -0.59 -1.64 1.37 -0.22 -1.36 1.87 -0.39 1.32 1952 0.93 -0.83 -1.49 1.01 -1.12 -0.40 -0.09 -0.28 -0.54 -0.73 -1.13 -0.43 1953 0.33 -0.49 -0.04 -1.67 -0.66 1.09 0.40 -0.71 -0.35 1.32 1.04 -0.47 1954 0.37 0.74 -0.83 1.34 -0.09 -0.25 -0.60 -1.90 -0.44 0.60 0.40 0.69 1955 -1.84 -1.12 -0.53 -0.42 -0.34 -1.10 1.76 1.07 0.32 -1.47 -1.29 0.17 1956 -0.22 -1.12 -0.05 -1.06 2.21 0.10 -0.75 -1.37 0.24 0.88 0.51 0.10 1957 1.05 0.11 -1.26 0.49 -0.79 -0.72 -1.19 -0.55 -1.66 1.32 0.73 0.12 1958 -0.54 -1.06 -1.96 0.37 -0.24 -1.38 -1.73 -1.56 -0.07 0.16 1.64 -0.70 1959 -0.87 0.68 -0.15 0.36 0.39 0.40 0.74 0.06 0.88 0.89 0.41 0.44 1960 -1.29 -1.89 -0.50 1.36 0.45 -0.21 0.35 -1.40 0.39 -1.73 -0.51 0.06 1961 0.41 0.45 0.55 -1.55 -0.36 0.86 -0.39 0.90 1.24 0.51 -0.62 -1.48 1962 0.61 0.55 -2.47 0.99 -0.10 0.16 -2.47 0.14 -0.37 0.41 -0.23 -1.32 1963 -2.12 -0.96 -0.43 -1.35 2.16 -0.43 -0.77 -0.64 1.79 0.94 -1.27 -1.92 1964 -0.95 -1.43 -1.20 0.36 0.52 1.29 1.90 -1.77 0.20 0.74 -0.01 -0.15 1965 -0.12 -1.55 -1.51 0.72 -0.62 0.29 0.32 0.45 0.37 0.38 -1.66 1.37 1966 -1.74 -1.39 0.56 -0.75 0.22 1.05 0.32 -1.76 -0.45 -0.68 -0.04 0.72 1967 -0.89 0.19 1.51 0.18 -0.99 1.40 0.41 1.44 0.93 0.07 0.60 -0.45 1968 0.13 -1.29 0.40 -1.08 -1.76 0.33 -0.80 -0.66 -1.92 -2.30 -0.93 -1.40 1969 -0.83 -1.55 -1.56 1.53 0.55 0.55 0.57 -1.45 2.07 0.66 -0.96 -0.28 1970 -1.50 0.64 -0.96 -1.30 1.14 1.55 0.10 0.10 -0.09 -0.92 -0.60 -1.20 1971 -1.13 0.24 -0.84 -0.24 0.50 -1.57 0.24 1.55 0.39 0.58 -0.20 0.60 1972 0.27 0.32 0.72 -0.22 0.95 0.88 0.18 1.32 -0.12 1.09 0.54 0.19 1973 0.04 0.85 0.30 -0.54 -0.44 0.39 0.57 -0.06 -0.30 -1.24 -0.93 0.32 1974 1.34 -0.14 -0.03 0.51 -0.24 -0.14 -0.76 -0.64 0.82 0.49 -0.54 1.50 1975 0.58 -0.62 -0.61 -1.60 -0.52 -0.84 1.55 -0.26 1.56 -0.54 0.41 0.00 1976 -0.25 0.93 0.75 0.26 0.96 0.80 -0.32 1.92 -1.29 -0.08 0.17 -1.60 1977 -1.04 -0.49 -0.81 0.65 -0.86 -0.57 -0.45 -0.28 0.37 0.52 -0.07 -1.00 1978 0.66 -2.20 0.70 -1.17 1.08 1.38 -1.14 0.64 0.46 1.93 3.04 -1.57 1979 -1.38 -0.67 0.78 -1.71 -1.03 1.60 0.83 0.96 1.01 -0.30 0.53 1.00 1980 -0.75 0.05 -0.31 1.29 -1.50 -0.37 -0.42 -2.24 0.66 -1.77 -0.37 0.78 1981 0.37 0.92 -1.19 0.36 0.20 -0.45 0.05 0.39 -1.45 -1.35 -0.38 -0.02 1982 -0.89 1.15 1.15 0.10 -0.53 -1.63 1.15 0.26 1.76 -0.74 1.60 1.78 1983 1.59 -0.53 0.95 -0.85 -0.07 0.99 1.19 1.61 -1.12 0.65 -0.98 0.29 1984 1.66 0.72 -0.37 -0.28 0.54 -0.42 -0.07 1.15 0.17 -0.07 -0.06 0.00 1985 -1.61 -0.49 0.20 0.32 -0.49 -0.80 1.22 -0.48 -0.52 0.90 -0.67 0.22 1986 1.11 -1.00 1.71 -0.59 0.85 1.22 0.12 -1.09 -1.12 1.55 2.29 0.99 1987 -1.15 -0.73 0.14 2.00 0.98 -1.82 0.52 -0.83 -1.22 0.14 0.18 0.32 1988 1.02 0.76 -0.17 -1.17 0.63 0.88 -0.35 0.04 -0.99 -1.08 -0.34 0.61 1989 1.17 2.00 1.85 0.28 1.38 -0.27 0.97 0.01 2.05 -0.03 0.16 -1.15 1990 1.04 1.41 1.46 2.00 -1.53 -0.02 0.53 0.97 1.06 0.23 -0.24 0.22 1991 0.86 1.04 -0.20 0.29 0.08 -0.82 -0.49 1.23 0.48 -0.19 0.48 0.46 1992 -0.13 1.07 0.87 1.86 2.63 0.20 0.16 0.85 -0.44 -1.76 1.19 0.47 1993 1.60 0.50 0.67 0.97 -0.78 -0.59 -3.18 0.12 -0.57 -0.71 2.56 1.56 1994 1.04 0.46 1.26 1.14 -0.57 1.52 1.31 0.38 -1.32 -0.97 0.64 2.02 1995 0.93 1.14 1.25 -0.85 -1.49 0.13 -0.22 0.69 0.31 0.19 -1.38 -1.67 1996 -0.12 -0.07 -0.24 -0.17 -1.06 0.56 0.67 1.02 -0.86 -0.33 -0.56 -1.41 1997 -0.49 1.70 1.46 -1.02 -0.28 -1.47 0.34 0.83 0.61 -1.70 -0.90 -0.96 1998 0.39 -0.11 0.87 -0.68 -1.32 -2.72 -0.48 -0.02 -2.00 -0.29 -0.28 0.87 1999 0.77 0.29 0.23 -0.95 0.92 1.12 -0.90 0.39 0.36 0.20 0.65 1.61 2000 0.60 1.70 0.77 -0.03 1.58 -0.03 -1.03 -0.29 -0.21 0.92 -0.92 -0.58 2001 0.25 0.45 -1.26 0.00 -0.02 -0.20 -0.25 -0.07 -0.65 -0.24 0.63 -0.83 2002 0.44 1.10 0.69 1.18 -0.22 0.38 0.62 0.38 -0.70 -2.28 -0.18 -0.94 2003 0.16 0.62 0.32 -0.18 0.01 -0.07 0.13 -0.07 0.01 -1.26 0.86 0.64 2004 -0.29 -0.14 1.02 1.15 0.19 -0.89 1.13 -0.48 0.38 -1.10 0.73 1.21 2005 1.52 -0.06 -1.83 -0.30 -1.25 -0.05 -0.51 0.37 0.63 -0.98 -0.31 -0.44 2006 1.27 -0.51 -1.28 1.24 -1.14 0.84 0.90 -1.73 -1.62 -2.24 0.44 1.34 2007 0.22 -0.47 1.44 0.17 0.66 -1.31 -0.58 -0.14 0.72 0.45 0.58 0.34 2008 0.89 0.73 0.08 -1.07 -1.73 -1.39 -1.27 -1.16 1.02 -0.04 -0.32 -0.28 2009 -0.01 0.06 0.57 -0.20 1.68 -1.21 -2.15 -0.19 1.51 -1.03 -0.02 -1.93 2010 -1.11 -1.98 -0.88 -0.72 -1.49 -0.82 -0.42 -1.22 -0.79 -0.93 -1.62 -1.85 2011 -0.88 0.70 0.61 2.48 -0.06 -1.28 -1.51 -1.35 0.54 0.39 1.36 2.52 2012 1.17 0.42 1.27 0.47 -0.91 -2.53 -1.32 -0.98 -0.59 -2.06 -0.58 0.17 2013 0.35 -0.45 -1.61 0.69 0.57 0.52 0.67 0.97 0.24 -1.28 0.90 0.95 2014 0.29 1.34 0.80 0.31 -0.92 -0.97 0.18 -1.68 1.62 -1.27 0.68 1.86 2015 1.79 1.32 1.45 0.73 0.15 -0.07 -3.18 -0.76 -0.65 0.44 1.74 2.24 2016 0.12 1.58 0.73 0.38 -0.77 -0.43 -1.76 -1.65 0.61 0.41 -0.16 0.48 2017 0.48 1.00 0.74 1.73 -1.91 0.05 1.26 -1.10 -0.61 0.19 0.00 0.88 2018 1.44 1.58 -0.93 1.24 2.12 1.09 1.39 1.97 1.67 0.93 -0.11 0.61 2019 0.59 0.29 1.23 0.47 -2.62 -1.09 -1.43 -1.17 -0.16 -1.41 0.28 1.20 2020 1.34 1.26 1.01 -1.02 -0.41 -0.15 -1.23 0.12 0.98 -0.65 2.54 -0.30 2021 -1.11 This is 1991-2020. Lots more "-NAO" winters now. 1950 0.56 0.01 -0.78 0.65 -0.50 0.25 -1.23 -0.19 0.39 1.43 -1.46 -1.03 1951 -0.42 0.35 -1.47 -0.38 -0.50 -1.35 1.39 -0.41 -1.18 2.54 -0.54 1.13 1952 0.57 -1.38 -1.97 0.95 -0.99 -0.10 -0.06 -0.49 -0.38 -0.28 -1.32 -0.49 1953 -0.12 -1.00 -0.45 -1.96 -0.56 1.41 0.43 -1.04 -0.19 1.95 0.96 -0.52 1954 -0.08 0.40 -1.27 1.31 -0.03 0.06 -0.57 -2.57 -0.28 1.16 0.29 0.55 1955 -2.65 -1.71 -0.96 -0.60 -0.26 -0.80 1.78 1.25 0.46 -1.09 -1.49 0.07 1956 -0.76 -1.71 -0.46 -1.30 2.10 0.41 -0.72 -1.89 0.38 1.47 0.40 0.00 1957 0.71 -0.32 -1.73 0.39 -0.68 -0.42 -1.16 -0.83 -1.47 1.95 0.63 0.02 1958 -1.14 -1.64 -2.46 0.26 -0.17 -1.08 -1.69 -2.13 0.08 0.68 1.59 -0.74 1959 -1.52 0.33 -0.56 0.25 0.41 0.71 0.77 -0.05 1.00 1.48 0.30 0.32 1960 -2.01 -2.59 -0.93 1.33 0.47 0.10 0.38 -1.93 0.53 -1.37 -0.67 -0.03 1961 -0.03 0.07 0.17 -1.83 -0.28 1.17 -0.36 1.03 1.36 1.07 -0.79 -1.46 1962 0.20 0.18 -2.99 0.93 -0.04 0.47 -2.43 0.05 -0.21 0.96 -0.38 -1.31 1963 -2.98 -1.53 -0.85 -1.61 2.05 -0.13 -0.74 -0.95 1.89 1.53 -1.47 -1.87 1964 -1.62 -2.06 -1.66 0.25 0.53 1.61 1.92 -2.40 0.34 1.32 -0.14 -0.23 1965 -0.65 -2.20 -1.99 0.64 -0.52 0.60 0.35 0.45 0.51 0.92 -1.88 1.18 1966 -2.54 -2.02 0.18 -0.96 0.25 1.37 0.35 -2.39 -0.29 -0.23 -0.18 0.58 1967 -1.55 -0.23 1.18 0.05 -0.87 1.72 0.44 1.73 1.05 0.59 0.50 -0.51 1968 -0.36 -1.91 0.02 -1.32 -1.58 0.64 -0.77 -0.97 -1.73 -1.99 -1.11 -1.39 1969 -1.48 -2.20 -2.04 1.52 0.56 0.86 0.60 -1.99 2.17 1.23 -1.14 -0.35 1970 -2.26 0.28 -1.41 -1.56 1.11 1.87 0.13 0.00 0.06 -0.49 -0.76 -1.20 1971 -1.82 -0.17 -1.28 -0.41 0.51 -1.28 0.27 1.87 0.53 1.14 -0.34 0.47 1972 -0.19 -0.08 0.35 -0.38 0.93 1.19 0.21 1.57 0.03 1.70 0.43 0.09 1973 -0.46 0.52 -0.09 -0.73 -0.36 0.70 0.60 -0.20 -0.15 -0.84 -1.11 0.21 1974 1.05 -0.60 -0.43 0.41 -0.17 0.17 -0.73 -0.95 0.95 1.04 -0.70 1.30 1975 0.17 -1.15 -1.04 -1.89 -0.43 -0.54 1.57 -0.46 1.67 -0.08 0.30 -0.09 1976 -0.80 0.61 0.38 0.14 0.94 1.11 -0.29 2.34 -1.11 0.42 0.04 -1.57 1977 -1.72 -1.00 -1.25 0.56 -0.75 -0.27 -0.42 -0.49 0.51 1.08 -0.21 -1.02 1978 0.26 -2.94 0.33 -1.42 1.05 1.70 -1.11 0.70 0.60 2.61 3.06 -1.54 1979 -2.12 -1.20 0.41 -2.01 -0.90 1.92 0.86 1.11 1.13 0.18 0.42 0.84 1980 -1.38 -0.39 -0.73 1.26 -1.34 -0.07 -0.39 -3.01 0.79 -1.41 -0.52 0.63 1981 -0.08 0.60 -1.65 0.25 0.24 -0.15 0.08 0.38 -1.27 -0.96 -0.53 -0.11 1982 -1.55 0.86 0.80 -0.04 -0.44 -1.34 1.18 0.21 1.86 -0.29 1.55 1.56 1983 1.34 -1.04 0.59 -1.07 -0.01 1.31 1.22 1.95 -0.95 1.22 -1.16 0.18 1984 1.42 0.37 -0.79 -0.45 0.55 -0.12 -0.04 1.35 0.31 0.43 -0.20 -0.09 1985 -2.38 -1.00 -0.19 0.20 -0.40 -0.50 1.25 -0.74 -0.36 1.49 -0.84 0.11 1986 0.78 -1.58 1.39 -0.79 0.84 1.54 0.15 -1.53 -0.95 2.20 2.27 0.83 1987 -1.85 -1.27 -0.26 2.03 0.96 -1.53 0.55 -1.19 -1.04 0.66 0.06 0.21 1988 0.68 0.42 -0.58 -1.42 0.64 1.19 -0.32 -0.07 -0.82 -0.66 -0.49 0.48 1989 0.85 1.82 1.54 0.16 1.33 0.03 1.00 -0.11 2.15 0.48 0.03 -1.15 1990 0.70 1.16 1.13 2.03 -1.37 0.29 0.56 1.12 1.18 0.76 -0.39 0.11 1991 0.49 0.74 -0.61 0.17 0.12 -0.52 -0.46 1.46 0.61 0.30 0.37 0.34 1992 -0.66 0.77 0.51 1.88 2.49 0.51 0.19 0.97 -0.28 -1.40 1.12 0.35 1993 1.35 0.12 0.30 0.91 -0.67 -0.29 -3.14 0.03 -0.41 -0.26 2.56 1.36 1994 0.70 0.08 0.92 1.10 -0.48 1.84 1.34 0.36 -1.14 -0.54 0.54 1.78 1995 0.57 0.85 0.91 -1.07 -1.33 0.44 -0.19 0.76 0.45 0.72 -1.59 -1.64 1996 -0.65 -0.52 -0.66 -0.33 -0.93 0.87 0.70 1.19 -0.69 0.15 -0.72 -1.40 1997 -1.08 1.48 1.13 -1.25 -0.21 -1.17 0.37 0.94 0.74 -1.34 -1.08 -0.98 1998 -0.05 -0.57 0.51 -0.88 -1.17 -2.44 -0.45 -0.15 -1.80 0.20 -0.43 0.72 1999 0.39 -0.11 -0.16 -1.18 0.90 1.44 -0.87 0.38 0.50 0.73 0.55 1.40 2000 0.19 1.48 0.40 -0.18 1.52 0.28 -1.00 -0.50 -0.06 1.51 -1.10 -0.63 2001 -0.22 0.07 -1.73 -0.15 0.03 0.11 -0.22 -0.22 -0.49 0.25 0.53 -0.86 2002 0.00 0.80 0.32 1.14 -0.15 0.69 0.65 0.36 -0.54 -1.97 -0.32 -0.96 2003 -0.32 0.26 -0.07 -0.34 0.06 0.24 0.16 -0.22 0.16 -0.86 0.77 0.50 2004 -0.85 -0.60 0.67 1.11 0.23 -0.59 1.16 -0.74 0.52 -0.69 0.63 1.03 2005 1.26 -0.51 -2.32 -0.47 -1.11 0.26 -0.48 0.35 0.76 -0.55 -0.46 -0.50 2006 0.97 -1.02 -1.75 1.20 -1.01 1.15 0.93 -2.35 -1.43 -1.92 0.33 1.15 2007 -0.25 -0.98 1.11 0.04 0.66 -1.01 -0.55 -0.31 0.85 1.00 0.48 0.23 2008 0.53 0.38 -0.32 -1.31 -1.55 -1.09 -1.24 -1.62 1.14 0.47 -0.47 -0.35 2009 -0.52 -0.38 0.19 -0.36 1.61 -0.91 -2.11 -0.37 1.62 -0.61 -0.16 -1.88 2010 -1.80 -2.69 -1.33 -0.93 -1.33 -0.52 -0.39 -1.69 -0.62 -0.50 -1.84 -1.80 2011 -1.53 0.35 0.24 2.55 -0.01 -0.98 -1.48 -1.85 0.67 0.94 1.30 2.25 2012 0.86 0.03 0.93 0.37 -0.79 -2.25 -1.29 -1.39 -0.43 -1.73 -0.74 0.07 2013 -0.11 -0.96 -2.09 0.60 0.58 0.83 0.70 1.12 0.38 -0.88 0.81 0.79 2014 -0.17 1.07 0.44 0.19 -0.80 -0.67 0.21 -2.28 1.72 -0.87 0.58 1.63 2015 1.57 1.05 1.12 0.64 0.19 0.24 -3.14 -1.10 -0.49 0.99 1.70 1.99 2016 -0.37 1.35 0.37 0.26 -0.67 -0.13 -1.72 -2.24 0.74 0.96 -0.31 0.35 2017 0.05 0.69 0.37 1.74 -1.72 0.35 1.28 -1.53 -0.45 0.71 -0.14 0.73 2018 1.17 1.34 -1.38 1.20 2.02 1.41 1.42 2.40 1.78 1.53 -0.25 0.48 2019 0.18 -0.11 0.89 0.36 -2.38 -0.79 -1.39 -1.62 -0.01 -1.03 0.16 1.02 2020 1.05 0.98 0.66 -1.26 -0.33 0.16 -1.19 0.03 1.11 -0.20 2.54 -0.37 2021 -1.80 -0.29 -99.90 -99.90 -99.90 -99.90 -99.90 -99.90 -99.90 -99.90 -99.90 -99.90

Feb 1.2 3 3.4 4 Match 2021 25.24 25.70 25.71 27.17 0.00 1951 25.19 25.65 25.71 27.09 0.18 1955 24.97 25.70 25.81 27.11 0.43 1956 24.90 25.70 25.76 27.01 0.55 2009 25.42 25.84 25.96 27.35 0.75 2011 25.94 25.63 25.64 27.15 0.86 1963 25.28 25.79 26.22 27.48 0.95 Top matches for February. The look for March is cold North, warm South when the six are blended.

The La Nina finished above 25.5C for winter overall. Nino 4 never dropped below 27.0C on the monthly data either. https://www.psl.noaa.gov/data/correlation/nina34.data 25.57C in DJF for 2020-21 25.72C in DJF in 2017-18 25.76C in DJF in 2011-12 The 2010-11 La Nina is still the last DJF to fall below 25.5C overall, it was 25.2C.

Pretty interesting looking winter globally for SST patterns.

For people who get on me about average temperatures, my forecast was actually better using average temperatures than high temperatures. The map is just 2020-21 minus the ten years I used as the analog blend. Warm colors are where 2020-21 was warmer than the analog blend. Cold colors are where 2020-21 was colder than the analog blend. You can see 75% of the US at least is within 0-3F degrees of what I had. My scoring system is essentially: w/in 0.5F = 100% (A+) w/in 1.0F = 95% w/in 2.0F = 85% w/in 3.0F = 75% etc That's why I showed the maps as within 3F. More than 3F out is not a good seasonal forecast for a given spot to me.

Pretty impressively dry winter nationally. Especially since this winter will likely be thought of as "stormy" for the US. Albuquerque is already guaranteed a pretty snowy season overall, but the winter itself had only 60% of normal precipitation. The real dry spots were the Montana/North Dakota border, SE NM, and California generally.

My forecast was for highs. Most people are asleep at six in the morning. I am just evaluating what I forecast from October for the US in winter. I don't think you actually understand what I am showing. The map shows the difference between the blend of highs I used and the observations. It is not showing whether you finished warm or cold compared to some baseline like 1981-2010 or 1991-2020 average. Here is Buffalo highs for Dec 1-Feb 28: 1995-96: 30.5F 2003-04: 31.7F 2007-08: 34.5F (x5) 2012-13: 37.0F (x2) 2019-20: 38.0F Blend: 34.67F, and I round it to 34.7F. 2020-21 Actual: 34.5F The Map says I was within 0.2 degrees of the high observed in Buffalo, from a blend I used to forecast the winter in October.

Here is my winter forecast verification. This is analog highs - observed highs. My guess is this winter will look pretty cold against 1991-2020 averages, but not the 1951-2010 baseline I used. Just since yesterday, the distance from the analogs to the observations shrank by up to 0.5F across the southern US. I think two more warm days would have fixed all of the South but Texas.

The sub-subsurface waters warmed to -0.83 for February 2021. https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/ocean/index/heat_content_index.txt Pretty decent rebound this week for Nino 1.2, Nino 3, and Nino 3.4. Winter likely finished around 25.7C in Nino 3.4 again, given 25.8C or so in Nino 3.4 for February. Nino1+2 Nino3 Nino34 Nino4 Week SST SSTA SST SSTA SST SSTA SST SSTA 09DEC2020 22.4-0.0 24.3-0.9 25.4-1.3 27.7-0.9 16DEC2020 22.0-0.7 24.3-0.9 25.6-1.0 27.8-0.8 23DEC2020 22.1-1.0 24.5-0.8 25.7-1.0 27.6-0.9 30DEC2020 22.2-1.3 24.4-1.0 25.4-1.2 27.3-1.2 06JAN2021 23.1-0.8 24.7-0.8 25.5-1.1 27.1-1.3 13JAN2021 24.0-0.3 24.7-0.9 25.4-1.2 27.0-1.3 20JAN2021 23.9-0.8 25.2-0.6 25.5-1.1 26.9-1.4 27JAN2021 24.6-0.5 25.7-0.2 25.9-0.7 27.1-1.1 03FEB2021 25.3-0.2 25.8-0.3 26.0-0.7 27.2-1.1 10FEB2021 25.4-0.5 25.4-0.9 25.5-1.2 27.0-1.2 17FEB2021 25.7-0.5 26.2-0.3 26.0-0.7 27.2-1.0 24FEB2021 25.2-1.1 25.7-0.9 25.7-1.2 27.2-1.0

The Canadian has the La Nina weaker than before near Peru in the coming months. Hangs on well in Nino 4, then re-develops to a weak La Nina basin wide later in 2021.

Long-term, a big +SOI February is correlated to cold NW US. But the look on the models implies the SW & Northern Plains should be colder than what is shown to me, We'll see. It's hard to get the SW too hot in March if the WPO and NAO are both favorable as the models hint.

Top SOI Matches for Dec-Feb: Year Dec Jan Feb 1938 12.5 16.5 7.2 1942 12.5 8.8 10.1 1973 15.6 20.3 16.0 1975 17.6 11.2 12.6 1988 9.5 12.7 8.5 1998 11.7 14.7 7.1 2020 16.6 15.9 11.3 February 1989 is similarly cold nationally to this year. That's the March to watch.

Here is my preliminary forecast result compared to observations. I did better in the eastern half of the US than the western half. But I'd say ~90% of the Eastern US was close to the analog blend for average highs in winter (<3F different than the analogs), and ~55% of the Western US was close. The South looks real warm again tomorrow, so the errors by Lexington, Charleston, Little Rock, and Memphis should all take another big jump back toward the analog blend. Earlier in the month, at the height of the cold wave I lost almost all of the South. There were also huge changes between 1/31 and 2/12 when the pattern flipped very cold. Billings finished within 1F or so of the analog blend high for DJF after being out by 7F from Dec-Jan.

I don't think the models really have the right idea for the cold in March. It looks like to me like there is a lot of warmth but also some powerful cold shots at times. I'm still fairly convinced there is one final big system for the Northeast, likely a Nor'easter, that moves through the Southwest first mid-month. The MJO now looks like it could get into the fun phases for active weather too. I'm not sure I buy it sustaining the whole month. But the Euro probably has the right idea putting the MJO in phase 8 in early March. A run from phase 8 to phase 4 in March would be consistent with the variation I expect for Spring.

People in the future are probably not going to talk about the very warm week one and week four of February 2021 given how cold the middle of the month was.

The SOI crashes in recent days favor some kind of big storm or storms over the SW around 3/5-3/7. These are the most negative values of 2021, and since at least November of last year. I'm inclined to believe one of these systems may be able to pick up some moisture from the subtropical jet. We'll see. Still like 3/12-3/16 also, given the 970 mb low south of the southern most tip of Kamchatka recently. Date Tahiti (hPa) Darwin (hPa) Daily Contribution 30 day Av. SOI 90 day Av. SOI 26 Feb 2021 1007.90 1005.15 -9.56 12.12 15.33 25 Feb 2021 1008.06 1006.40 -14.79 13.45 15.45 24 Feb 2021 1010.22 1006.20 -3.46 14.79 15.65 23 Feb 2021 1011.86 1005.55 7.54 15.24 15.75 22 Feb 2021 1012.44 1003.90 18.25 15.18 15.73 Warmth this month is slowly destroying the extent and magnitude of the cold. Month should still finish pretty cold overall. But the past week was predominantly warm in the northern US.

Lowest daily SOI value since late November on the update tonight. I've been targeting roughly week two of March for some good storms out here, either New Mexico, Colorado, or both for a while now. We have SOI support for something 3/5-3/6, and the Bering Straight Rule supports something 3/12-3/16, given that the big 970 mb (ish) low moved south of Kamchatka today. Date Tahiti (hPa) Darwin (hPa) Daily Contribution 30 day Av. SOI 90 day Av. SOI 24 Feb 2021 1010.22 1006.20 -3.46 14.79 15.65 23 Feb 2021 1011.86 1005.55 7.54 15.24 15.75 22 Feb 2021 1012.44 1003.90 18.25 15.18 15.73