Raw model output on the native 0.25° grid — no MOS, no bias correction, no post-processing. Scores understate operational forecast quality. Read the fairness statement →

CastCheck methodology v0.2 · data through 2026-08-30

GraphCast (IFS init) (graphcast_ifs)

source aiwp · product GRAP · initial conditions from IFS · steps every 6 h to 240 h · initializations 0, 12 UTC.

Scores use the latest model version segment, GRAP_v100, starting 2026-01-01. Earlier days ran a different version of the model and are excluded rather than silently pooled into the same average.

These pages are always bilinear interpolation, the headline method. The nearest-node variant, and every other window/initialization/interpolation/variable combination, is published on each permanent link below — follow any number.

Daily maximum temperature — MAE °F by station

the last 365 days, 00Z, bilinear. MAE with the bias and n underneath; every cell links to its permanent page. The sparkline shows this station across lead days 1–9 on a scale shared within this table.
Stationd0d1d2d3d4d5d6d7d8d9lead 1–9
KATL 5.67-5.65 · n=34 5.85-5.85 · n=33 5.86-5.86 · n=32 5.93-5.93 · n=31 5.52-5.51 · n=31 5.31-5.29 · n=31 5.99-5.78 · n=30 6.35-6.18 · n=29 6.29-5.66 · n=28 6.92-5.54 · n=27 KATL MAE by lead day 1 to 9, tmax
KAUS 7.34-7.34 · n=34 7.72-7.72 · n=33 7.62-7.62 · n=32 7.47-7.47 · n=31 7.22-7.22 · n=31 7.52-7.52 · n=31 7.50-7.50 · n=30 7.05-7.05 · n=29 6.26-5.90 · n=28 7.56-5.84 · n=27 KAUS MAE by lead day 1 to 9, tmax
KBOS 2.82-2.46 · n=33 2.79-2.37 · n=33 3.20-2.72 · n=32 3.59-2.54 · n=30 4.31-2.03 · n=30 4.28-1.40 · n=30 4.64-1.54 · n=29 4.71-1.64 · n=28 5.05-1.60 · n=27 5.84-2.67 · n=26 KBOS MAE by lead day 1 to 9, tmax
KDCA 4.33-4.33 · n=34 4.62-4.62 · n=33 4.53-4.53 · n=32 4.57-4.27 · n=31 4.57-3.72 · n=31 4.96-3.06 · n=31 5.37-3.37 · n=30 5.13-3.35 · n=29 6.13-4.04 · n=28 6.78-4.29 · n=27 KDCA MAE by lead day 1 to 9, tmax
KDEN 5.98-5.98 · n=34 6.26-6.26 · n=33 6.64-6.61 · n=32 6.65-6.65 · n=31 7.08-7.08 · n=31 7.61-7.61 · n=31 7.77-7.62 · n=30 8.67-8.20 · n=29 9.28-8.76 · n=28 —KDEN MAE by lead day 1 to 9, tmax
KDFW 5.23-5.15 · n=34 6.26-6.22 · n=33 7.03-7.03 · n=32 7.19-7.19 · n=31 7.16-7.09 · n=31 7.71-7.50 · n=31 8.27-8.27 · n=30 8.15-7.93 · n=29 7.99-7.43 · n=28 8.52-6.95 · n=27 KDFW MAE by lead day 1 to 9, tmax
KEWR 4.35-4.35 · n=34 4.55-4.55 · n=33 4.60-4.60 · n=32 4.62-4.62 · n=31 4.76-4.73 · n=31 4.24-3.70 · n=31 4.75-3.84 · n=30 4.06-3.91 · n=29 4.69-4.03 · n=28 6.14-4.33 · n=27 KEWR MAE by lead day 1 to 9, tmax
KIAH 5.79-5.79 · n=34 6.48-6.48 · n=33 6.51-6.51 · n=32 6.68-6.68 · n=31 6.56-6.56 · n=31 6.70-6.70 · n=31 6.71-6.71 · n=30 6.23-6.13 · n=29 5.57-5.01 · n=28 6.81-4.71 · n=27 KIAH MAE by lead day 1 to 9, tmax
KLAS 5.08-4.89 · n=34 4.89-4.75 · n=33 5.51-5.24 · n=32 5.56-5.38 · n=31 6.26-5.74 · n=31 6.07-5.68 · n=31 6.98-6.35 · n=30 7.33-6.99 · n=29 8.82-8.26 · n=28 —KLAS MAE by lead day 1 to 9, tmax
KLAX 3.21-3.21 · n=34 3.39-3.39 · n=33 3.48-3.48 · n=32 3.42-3.37 · n=31 3.56-3.53 · n=31 3.69-3.57 · n=31 3.86-3.64 · n=30 4.11-3.93 · n=29 4.78-4.76 · n=28 —KLAX MAE by lead day 1 to 9, tmax
KMIA 3.48-3.48 · n=34 4.18-4.18 · n=33 4.40-4.40 · n=32 4.18-4.18 · n=31 4.31-4.31 · n=31 4.74-4.74 · n=31 4.76-4.73 · n=30 5.32-4.91 · n=29 5.18-5.14 · n=28 5.45-5.12 · n=27 KMIA MAE by lead day 1 to 9, tmax
KMSP 4.95-4.95 · n=34 5.82-5.82 · n=33 5.62-5.62 · n=32 5.85-5.71 · n=31 5.58-5.48 · n=31 6.22-5.87 · n=31 6.44-6.30 · n=30 7.00-6.70 · n=29 6.42-6.22 · n=28 6.90-6.29 · n=27 KMSP MAE by lead day 1 to 9, tmax
KMSY 4.95-4.89 · n=34 5.29-5.22 · n=33 5.13-5.13 · n=32 5.30-5.30 · n=31 5.79-5.79 · n=31 5.54-5.54 · n=31 5.78-5.73 · n=30 5.71-5.71 · n=29 5.02-5.02 · n=28 5.21-4.07 · n=27 KMSY MAE by lead day 1 to 9, tmax
KNYC 1.93-1.53 · n=34 1.99-1.61 · n=33 2.36-1.66 · n=32 2.56-1.98 · n=31 2.88-2.09 · n=31 2.99-0.77 · n=31 3.07-1.06 · n=30 2.53-1.22 · n=29 3.74-1.42 · n=28 5.07-1.87 · n=27 KNYC MAE by lead day 1 to 9, tmax
KOKC 6.48-6.48 · n=34 7.16-7.16 · n=33 7.69-7.69 · n=32 8.31-8.31 · n=31 8.46-8.46 · n=31 8.59-8.37 · n=31 9.64-9.64 · n=30 9.97-9.97 · n=29 10.28-9.59 · n=28 10.09-8.39 · n=27 KOKC MAE by lead day 1 to 9, tmax
KORD 3.49-3.49 · n=34 3.57-3.55 · n=33 4.40-4.32 · n=32 4.33-4.29 · n=31 4.50-4.32 · n=31 3.85-3.49 · n=31 4.80-4.40 · n=30 5.43-4.70 · n=29 5.55-4.21 · n=28 6.20-4.57 · n=27 KORD MAE by lead day 1 to 9, tmax
KPHL 4.36-4.32 · n=34 4.65-4.60 · n=33 4.54-4.52 · n=32 4.37-4.28 · n=31 4.22-4.12 · n=31 4.60-3.31 · n=31 5.20-3.48 · n=30 4.69-3.68 · n=29 5.44-3.99 · n=28 6.65-4.16 · n=27 KPHL MAE by lead day 1 to 9, tmax
KPHX 3.25-3.06 · n=34 3.71-3.55 · n=33 3.94-3.83 · n=32 3.93-3.85 · n=31 4.24-4.15 · n=31 5.08-4.92 · n=31 5.49-5.33 · n=30 6.14-5.92 · n=29 7.95-7.77 · n=28 —KPHX MAE by lead day 1 to 9, tmax
KSAN 5.12-5.12 · n=34 5.53-5.53 · n=33 5.38-5.38 · n=32 5.49-5.49 · n=31 5.47-5.47 · n=31 5.22-5.22 · n=31 4.99-4.99 · n=30 4.99-4.99 · n=29 5.55-5.51 · n=28 —KSAN MAE by lead day 1 to 9, tmax
KSAT 5.83-5.83 · n=34 6.18-6.18 · n=33 6.02-6.02 · n=32 6.06-6.06 · n=31 5.80-5.77 · n=31 6.12-6.12 · n=31 5.87-5.87 · n=30 5.53-5.53 · n=29 5.12-4.80 · n=28 6.20-4.97 · n=27 KSAT MAE by lead day 1 to 9, tmax
KSEA 4.15-4.12 · n=34 4.23-4.16 · n=33 4.31-4.17 · n=32 4.10-3.93 · n=31 4.49-4.21 · n=31 4.96-4.49 · n=31 5.76-5.10 · n=30 6.28-5.43 · n=29 6.78-6.62 · n=28 —KSEA MAE by lead day 1 to 9, tmax
KSFO 4.39-4.23 · n=34 4.75-4.62 · n=33 4.83-4.75 · n=32 4.72-4.50 · n=31 4.61-4.50 · n=31 4.89-4.65 · n=31 4.95-4.72 · n=30 5.12-4.91 · n=29 5.70-5.28 · n=28 —KSFO MAE by lead day 1 to 9, tmax
KTTN 1.91-1.65 · n=34 2.17-1.82 · n=33 2.37-1.79 · n=32 2.33-1.58 · n=31 2.68-1.63 · n=31 2.72-0.61 · n=31 3.05-0.76 · n=30 2.57-0.93 · n=29 3.47-1.22 · n=28 4.78-1.35 · n=27 KTTN MAE by lead day 1 to 9, tmax

Up to 3 of the scored days in this table carry a QC flag on the observation (a CLI value that disagreed with the hourly observations, or a fallback source). They are kept in the scores and counted here rather than dropped — see methodology.

+ model too warm · − model too cold · bias interval includes zero · ★ lowest MAE · = not distinguishable from the leader · ▼ significantly worse · n < 30 greyed and unranked · CI is a 95 % moving-block bootstrap interval.

Daily minimum temperature — MAE °F by station

the last 365 days, 00Z, bilinear. MAE with the bias and n underneath; every cell links to its permanent page. The sparkline shows this station across lead days 1–9 on a scale shared within this table.
Stationd0d1d2d3d4d5d6d7d8d9lead 1–9
KATL 1.50-0.55 · n=34 1.60-0.48 · n=33 1.93-0.59 · n=32 2.03-0.82 · n=31 2.07-0.38 · n=31 2.24-0.06 · n=31 2.68-0.29 · n=30 3.08-0.49 · n=29 3.09-0.36 · n=28 3.11+0.94 · n=27 KATL MAE by lead day 1 to 9, tmin
KAUS 5.36+5.36 · n=34 5.58+5.55 · n=33 5.47+5.41 · n=32 5.30+5.28 · n=31 5.34+5.34 · n=31 5.16+5.16 · n=31 4.83+4.83 · n=30 4.59+4.19 · n=29 4.97+4.69 · n=28 5.74+5.46 · n=27 KAUS MAE by lead day 1 to 9, tmin
KBOS 1.42-0.28 · n=33 1.77-0.43 · n=33 1.81-0.44 · n=32 1.55-0.23 · n=30 1.72+0.17 · n=30 2.29+0.48 · n=30 2.38+0.58 · n=29 2.55+0.39 · n=28 2.76-0.65 · n=27 3.92-0.91 · n=26 KBOS MAE by lead day 1 to 9, tmin
KDCA 1.42+0.07 · n=34 1.72+0.17 · n=33 2.16+0.25 · n=32 2.24+0.44 · n=31 2.66+0.65 · n=31 3.24+1.10 · n=31 3.47+1.40 · n=30 3.55+1.04 · n=29 3.45+0.06 · n=28 4.37-1.01 · n=27 KDCA MAE by lead day 1 to 9, tmin
KDEN 3.22+2.80 · n=34 3.49+2.98 · n=33 3.21+2.65 · n=32 2.95+2.48 · n=31 3.07+2.68 · n=31 2.85+2.02 · n=31 2.69+1.99 · n=30 3.14+1.64 · n=29 3.54+1.10 · n=28 —KDEN MAE by lead day 1 to 9, tmin
KDFW 1.80+1.55 · n=34 1.49+1.03 · n=33 1.67+0.52 · n=32 1.99+0.05 · n=31 2.43+0.03 · n=31 2.26-0.30 · n=31 2.29-0.66 · n=30 2.17-0.91 · n=29 2.51-0.22 · n=28 3.20+0.56 · n=27 KDFW MAE by lead day 1 to 9, tmin
KEWR 1.77+0.84 · n=34 1.94+0.45 · n=33 2.15+0.47 · n=32 2.48+0.84 · n=31 2.51+0.86 · n=31 2.78+0.93 · n=31 3.15+1.35 · n=30 3.23+1.40 · n=29 3.34+0.60 · n=28 3.19+0.17 · n=27 KEWR MAE by lead day 1 to 9, tmin
KIAH 2.30+1.56 · n=34 2.23+1.00 · n=33 2.21+0.74 · n=32 2.47+0.82 · n=31 2.51+0.79 · n=31 2.53+0.51 · n=31 2.82+0.73 · n=30 2.81+0.88 · n=29 2.84+0.90 · n=28 4.25+1.62 · n=27 KIAH MAE by lead day 1 to 9, tmin
KLAS 2.26-1.44 · n=34 2.70-2.10 · n=33 2.85-2.30 · n=32 2.89-2.24 · n=31 3.45-2.26 · n=31 4.27-2.43 · n=31 4.65-2.35 · n=30 5.46-2.43 · n=29 5.91-2.66 · n=28 —KLAS MAE by lead day 1 to 9, tmin
KLAX 0.90+0.16 · n=34 1.16-0.15 · n=33 1.27-0.32 · n=32 1.42-0.04 · n=31 1.54+0.20 · n=31 1.95+0.60 · n=31 2.42+1.10 · n=30 3.13+1.56 · n=29 3.60+1.61 · n=28 —KLAX MAE by lead day 1 to 9, tmin
KMIA 1.54+0.78 · n=34 1.71+0.27 · n=33 1.71+0.11 · n=32 1.42-0.28 · n=31 1.46-0.30 · n=31 1.82-0.49 · n=31 1.75-0.39 · n=30 2.13-1.15 · n=29 2.61-1.63 · n=28 3.86-1.66 · n=27 KMIA MAE by lead day 1 to 9, tmin
KMSP 1.75-0.85 · n=34 1.87-1.32 · n=33 2.14-1.22 · n=32 2.34-1.55 · n=31 2.25-1.33 · n=31 2.96-1.34 · n=31 3.96-1.52 · n=30 4.32-1.33 · n=29 5.15-1.57 · n=28 6.12-1.30 · n=27 KMSP MAE by lead day 1 to 9, tmin
KMSY 3.26+3.12 · n=34 3.04+2.76 · n=33 3.12+2.72 · n=32 2.77+2.48 · n=31 2.94+2.59 · n=31 2.78+2.09 · n=31 2.97+2.19 · n=30 3.14+2.13 · n=29 2.69+1.91 · n=28 3.48+2.97 · n=27 KMSY MAE by lead day 1 to 9, tmin
KNYC 2.12+0.49 · n=34 2.01+0.08 · n=33 2.27+0.11 · n=32 2.55+0.56 · n=31 2.65+0.64 · n=31 2.90+0.82 · n=31 3.19+1.31 · n=30 2.93+1.05 · n=29 3.90-0.01 · n=28 3.59-0.10 · n=27 KNYC MAE by lead day 1 to 9, tmin
KOKC 4.84+4.78 · n=34 4.42+4.33 · n=33 4.88+4.42 · n=32 4.65+3.88 · n=31 4.40+3.62 · n=31 4.05+3.32 · n=31 4.02+2.72 · n=30 3.53+2.05 · n=29 3.24+2.36 · n=28 4.37+2.80 · n=27 KOKC MAE by lead day 1 to 9, tmin
KORD 1.51+0.19 · n=34 1.60+0.10 · n=33 1.51-0.30 · n=32 1.85-0.35 · n=31 2.09-0.02 · n=31 1.99+0.25 · n=31 2.43+0.14 · n=30 3.54-0.20 · n=29 4.85+0.39 · n=28 5.68+0.07 · n=27 KORD MAE by lead day 1 to 9, tmin
KPHL 1.51-0.88 · n=34 1.89-0.91 · n=33 1.87-0.61 · n=32 1.98-0.12 · n=31 2.54+0.04 · n=31 2.83+0.21 · n=31 3.15+0.73 · n=30 3.46+0.67 · n=29 3.12-0.54 · n=28 3.56-1.32 · n=27 KPHL MAE by lead day 1 to 9, tmin
KPHX 2.53-0.40 · n=34 2.64-0.35 · n=33 2.59-0.72 · n=32 2.95-0.67 · n=31 2.95-0.87 · n=31 3.43-0.85 · n=31 4.11-1.43 · n=30 4.17-0.98 · n=29 4.12-1.33 · n=28 —KPHX MAE by lead day 1 to 9, tmin
KSAN 1.05-0.10 · n=34 1.25-0.27 · n=33 1.35-0.01 · n=32 1.41+0.41 · n=31 1.69+0.88 · n=31 2.12+1.46 · n=31 2.70+2.08 · n=30 3.31+2.83 · n=29 3.88+2.94 · n=28 —KSAN MAE by lead day 1 to 9, tmin
KSAT 1.73+0.93 · n=34 1.56+0.84 · n=33 1.64+1.04 · n=32 1.60+1.19 · n=31 1.81+1.51 · n=31 1.97+1.58 · n=31 1.52+1.32 · n=30 2.13+1.07 · n=29 2.16+1.06 · n=28 3.23+2.17 · n=27 KSAT MAE by lead day 1 to 9, tmin
KSEA 2.25+1.93 · n=34 1.79+1.50 · n=33 1.73+1.50 · n=32 1.74+1.51 · n=31 2.13+1.98 · n=31 1.90+1.87 · n=31 2.06+1.58 · n=30 2.98+0.51 · n=29 3.61-0.42 · n=28 —KSEA MAE by lead day 1 to 9, tmin
KSFO 0.70+0.48 · n=34 0.78+0.20 · n=33 0.93-0.03 · n=32 1.23-0.31 · n=31 1.32-0.52 · n=31 1.53-0.62 · n=31 1.67-0.63 · n=30 1.98-0.45 · n=29 1.89-0.03 · n=28 —KSFO MAE by lead day 1 to 9, tmin
KTTN 3.08+3.08 · n=34 3.11+3.08 · n=33 3.45+3.37 · n=32 3.82+3.82 · n=31 4.07+3.91 · n=31 4.33+4.05 · n=31 4.54+4.41 · n=30 4.87+4.50 · n=29 4.17+3.36 · n=28 4.02+2.76 · n=27 KTTN MAE by lead day 1 to 9, tmin

Up to 2 of the scored days in this table carry a QC flag on the observation (a CLI value that disagreed with the hourly observations, or a fallback source). They are kept in the scores and counted here rather than dropped — see methodology.

Month-by-month slices live on the canonical page: they do not depend on the window, initialization or interpolation selected here.

Source and licence

Where it comes from

aiwp · GRAP · IFS initial conditions

Steps every 6 h to 240 h; sampled at 00/06/12/18 UTC only.

Licence

NOAA/CIRA AIWP, U.S. Government work, public domain. Cite Radford et al. (2025), BAMS, doi:10.1175/BAMS-D-24-0057.1.

Post-processing

None. Raw grid values, bilinear (headline) or nearest-node interpolation, no MOS, no bias correction, no downscaling.

All scores as JSON scores_latest.csv daily_errors.csv.gz data & licences