Table 3: Percentage improvement over mean debiased CFSv2 RMSE when forecasting temperature in the contiguous U.S. The best performing models within each class of models are shown in bold, while the best performing models overall are shown in green.
Temperature, weeks 3-4
Group	Model	2011	2012	2013	2014	2015	2016	2017	2018	2019	2020	Overall
Baselines	Climatology	-0.89±3.85	-7.52±4.56	5.8±3.62	1.32±3.86	-7.91±4.85	-5.54±5.79	3.93±3.72	4.32±3.62	2.1±4.43	3.81±4.36	0.13±1.35
Persistence	-122.09±14.57	-117.74±11.91	-120.23±16.63	-115.49±19.12	-112.3±18.61	-128.89±17.9	-78.66±12.11	-98.39±13.72	-111.15±23.56	-101.39±16.54	-109.94±5.29
ABC	Climatology++	0.68±3.58	-7.03±4.31	5.17±3.72	1.87±3.86	-3.74±4.36	-4.99±6.12	5.83±3.84	6.25±3.24	4.43±4.01	10.15±3.66	2.06±1.3
CSFs2+2+	5.35±3.63	8.71±3.04	3.12±3.26	7.36±3.85	2.68±3.38	6.17±3.86	7.94±3.28	6.87±2.77	7.88±2.89	4.29±3.29	5.92±1.05
Persistence++	7.06±3.21	4.33±3.37	5.91±3.04	5.54±3.77	0.23±3.67	4.11±4.19	6.1±3.31	10.16±2.54	3.12±3.2	13.21±2.79	6.0±1.06
Learning	AutoKNN	0.52±4.05	-7.99±4.65	5.74±3.17	1.25±3.86	-7.27±4.92	-4.6±5.47	4.93±3.48	4.71±3.59	2.75±3.88	7.44±4.14	0.93±1.34
LocalBoosting	-3.74±4.23	-6.89±4.57	2.92±2.98	-1.92±4.19	-5.86±4.28	-5.23±5.7	-0.6±3.76	5.62±3.15	1.45±3.18	5.19±3.54	-0.76±1.23
MultiLLR	6.37±3.53	0.97±3.85	3.0±3.47	2.57±3.54	-2.43±3.03	-7.23±5.75	3.83±3.68	3.8±3.25	8.3±3.08	4.15±3.09	2.45±1.17
Prophet	0.19±4.22	-7.89±4.41	1.81±3.83	1.07±4.4	-7.88±4.82	-2.5±4.9	5.95±4.07	6.59±3.52	2.22±4.69	9.97±4.18	1.13±1.36
Salient 2.0	-7.6±4.9	-13.08±5.82	-7.81±4.41	-22.21±6.47	-11.02±6.4	-19.04±6.79	2.71±3.44	9.03±3.05	-10.54±6.2	6.48±5.16	-6.95±1.76
Ensembles	Uniform ABC	6.23±3.41	4.08±3.34	6.32±2.91	6.57±3.69	1.12±3.73	4.39±4.17	7.34±3.25	9.14±2.78	7.08±3.06	11.79±2.79	6.46±1.05
Online ABC	5.57±3.26	6.49±3.25	5.2±3.07	7.3±3.78	2.39±3.33	6.49±3.9	7.86±3.16	9.01±2.62	6.77±2.59	10.44±2.66	6.71±1.01
Temperature, weeks 5-6
Baselines	Climatology	-3.49±3.33	-8.66±5.54	12.91±3.38	4.36±3.68	0.26±3.81	0.66±4.39	7.89±2.84	4.93±2.63	6.71±3.88	-0.05±4.37	2.93±1.23
Persistence	-206.03±22.74	-187.94±22.83	-169.31±24.87	-172.6±28.7	-147.71±27.59	-190.83±16.81	-127.66±18.96	-161.7±19.97	-169.53±27.67	-183.02±26.03	-170.1±7.56
ABC	Climatology++	-1.88±3.47	-8.17±5.4	12.32±3.64	4.89±3.3	4.11±3.39	1.18±4.4	10.0±2.54	6.84±2.5	8.93±3.45	6.55±3.85	4.83±1.18
CSFs2+2+	1.68±3.13	2.2±4.34	8.06±3.06	11.17±3.36	9.72±2.99	7.57±2.41	6.44±2.96	6.13±2.71	6.68±3.19	7.52±3.9	7.09±1.02
Persistence++	2.07±2.66	-1.33±4.6	11.68±2.86	5.35±3.09	4.81±2.84	6.31±3.44	8.87±2.39	7.99±1.94	8.26±2.96	8.45±3.25	6.43±0.99
Learning	AutoKNN	-3.49±3.43	-9.57±5.81	13.19±3.28	4.41±3.83	0.68±3.99	0.58±4.2	8.25±2.71	4.99±2.51	6.47±3.45	2.98±4.04	3.22±1.25
LocalBoosting	-9.97±5.0	-11.73±5.92	6.41±4.17	-3.2±4.09	2.21±3.31	-6.55±4.16	4.91±3.01	4.51±2.57	3.89±2.89	2.46±3.46	-0.29±1.24
MultiLLR	-3.27±4.39	-4.22±5.07	8.45±3.41	2.44±5.18	-1.58±3.55	2.76±3.46	4.0±2.79	3.18±2.7	6.35±3.66	1.98±4.3	2.21±1.24
Prophet	-2.7±3.69	-9.59±5.74	9.09±3.88	3.72±3.98	0.02±3.66	3.29±3.94	10.18±3.38	7.48±3.01	6.71±3.77	6.4±4.22	3.78±1.26
Salient 2.0	-9.34±5.44	-17.35±7.14	2.23±4.74	-21.18±6.46	-2.22±3.73	-14.66±5.25	5.78±3.57	9.22±3.34	-2.46±5.35	4.98±4.09	-4.05±1.73
Ensembles	Uniform ABC	2.35±2.95	-0.06±4.57	11.92±2.83	8.38±3.08	7.57±2.91	7.67±3.03	9.19±2.42	7.96±2.28	8.88±3.19	8.84±3.43	7.45±0.99
Online ABC	2.15±2.75	0.94±4.65	11.06±2.91	9.41±3.16	9.19±2.71	7.04±2.76	8.49±2.59	7.96±2.22	8.6±2.92	8.87±3.49	7.54±0.98