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WxSim & NWS Forecast Comparison

National Weather Service (NW), Actual Observed (Act), WxSim Generated (WS)
Morning Forecasts
Updated: 08-20-26 at 5:00 am
Goal Forecast Day Day +1 Day +2 Day +3
± 2.0° F High Low High Low High Low High Low
Date NW Act WS NW Act WS NW Act WS NW Act WS NW Act WS NW Act WS NW Act WS NW Act WS
08-20-26 57   87 84   60 57   82 82   66 56   78 83   67 56   85 85   63
08-19-26 57 87.6 88 89 66.6 69 58   83 85   65 57   84 83   66 57   77 84   66
08-17-26 56 86.2 87 84 67.3 68 55 87.6 88 86 66.6 69 57   87 86   70 57   88 84   65
08-16-26 54 82.4 86 85 60.6 65 56 86.2 86 83 67.3 66 55 87.6 86 84 66.6 68 56   87 85   69
08-15-26 55 84.0 85 79 63.3 65 54 82.4 86 83 60.6 67 55 86.2 88 81 67.3 68 54 87.6 87 83 66.6 68
08-14-26 55 86.4 88 77 63.7 63 54 84.0 85 78 63.3 65 54 82.4 86 81 60.6 65 54 86.2 84 78 67.3 66
08-13-26 56 86.9 89 74 68.7 66 56 86.4 88 75 63.7 63 54 84.0 85 78 63.3 68 54 82.4 82 79 60.6 68
Results NW Act WS NW Act WS NW Act WS NW Act WS NW Act WS NW Act WS NW Act WS NW Act WS
# Succ 0 4 0 3 0 4 0 3 0 3 0 2 0 2 0 2
% Succ     66.7     50.0     80.0     60.0     75.0     50.0     66.7     66.7
Ave Error 30.1   1.6 16.3   2.1 30.3   1.4 16.7   2.5 30.6   2.0 16.6   2.8 31.4   1.1 15.2   3.4
Net Error -30.1   1.6 16.3   1.0 -30.3   1.3 16.7   1.7 -30.6   1.2 16.6   2.8 -31.4   -1.1 15.2   2.5
Std Dev 1.0   1.0 4.3   1.3 1.3   1.2 2.9   1.8 1.0   0.2 0.4   0.7 0.0   0.0 0.0   0.0

Mid-Day Forecasts
Updated: 08-19-26 at 11:00 am
Goal Forecast Day Day +1 Day +2 Day +3
± 2.0° F High Low High Low High Low High Low
Date NW Act WS NW Act WS NW Act WS NW Act WS NW Act WS NW Act WS NW Act WS NW Act WS
08-19-26 89   91 58   70 85   84 57   63 83   84 57   67 84   76 56   65
08-18-26 88 86.2 87 57 66.6 69 88   88 58   71 85   83 57   65 83   85 55   66
08-17-26 84 78.4 86 55 67.3 68 86 86.2 88 57 66.6 69 86   87 57   71 84   88 57   66
08-16-26 85 82.4 88 56 67.6 64 83 78.4 85 55 67.3 69 84 86.2 85 56 66.6 68 85   88 56   67
08-15-26 79 84.0 87 54 60.6 66 84 82.4 85 55 67.6 65 82 78.4 86 55 67.3 66 83 86.2 88 56 66.6 66
08-14-26 77 86.4 90 54 63.3 65 78 84.0 85 54 60.6 66 81 82.4 85 54 67.6 66 78 78.4 78 54 67.3 66
08-13-26 74 86.9 91 56 63.7 68 75 86.4 87 54 63.3 63 78 84.0 84 54 60.6 68 79 82.4 82 54 67.6 68
Results NW Act WS NW Act WS NW Act WS NW Act WS NW Act WS NW Act WS NW Act WS NW Act WS
# Succ 1 1 0 2 2 3 0 2 1 2 0 3 1 3 0 3
% Succ 16.7   16.7     33.3 40.0   60.0     40.0 25.0   50.0     75.0 33.3   100.0     100.0
Ave Error 6.2   4.1 9.5   3.0 4.8   2.5 10.1   2.5 3.3   2.9 10.8   2.9 2.3   0.9 12.5   0.8
Net Error -2.9   4.1 -9.5   1.8 -2.3   2.5 -10.1   1.3 -1.5   2.3 -10.8   1.5 -2.3   0.3 -12.5   -0.5
Std Dev 2.7   2.1 1.9   1.5 2.5   1.9 1.5   0.4 0.5   0.8 0.1   0.8 0.0   0.0 0.0   0.0

Evening Forecasts
Updated: 08-19-26 at 5:00 pm
Goal Forecast Day Day +1 Day +2 Day +3
± 2.0° F Low High Low High Low High Low High
Date NW Act WS NW Act WS NW Act WS NW Act WS NW Act WS NW Act WS NW Act WS NW Act WS
08-19-26 89   70 57   86 85   61 57   82 83   63 56   77 84   64 56   82
08-18-26 86 66.6 67 57 86.2 87 87   70 57   80 84   63 57   84 82   65 55   79
08-17-26 84 67.3 67 56 78.4 85 86 66.6 68 57 86.2 88 88   71 58   85 85   67 57   76
08-16-26 85 67.6 63 56 82.4 86 83 67.3 67 55 78.4 87 84 66.6 67 56 86.2 88 85   68 56   76
08-15-26 79 60.6 67 54 84.0 86 84 67.6 64 55 82.4 86 82 67.3 67 55 78.4 86 83 66.6 68 56 86.2 87
08-14-26 77 63.3 65 55 86.4 84 79 60.6 67 54 84.0 85 82 67.6 66 54 82.4 82 79 67.3 65 54 78.4 85
08-13-26 74 63.7 68 55 86.9 89 75 63.3 64 54 86.4 85 78 60.6 68 53 84.0 81 79 67.6 66 54 82.4 88
Results NW Act WS NW Act WS NW Act WS NW Act WS NW Act WS NW Act WS NW Act WS NW Act WS
# Succ 0 3 0 2 0 3 0 3 0 3 0 2 0 2 0 1
% Succ     50.0     33.3     60.0     60.0     75.0     50.0     66.7     33.3
Ave Error 16.0   3.0 28.6   2.9 16.3   2.5 28.5   3.3 16.0   2.4 28.3   3.2 13.2   1.8 27.7   4.3
Net Error 16.0   1.3 -28.6   2.1 16.3   0.9 -28.5   2.7 16.0   1.5 -28.3   1.5 13.2   -0.8 -27.7   4.3
Std Dev 2.1   2.2 3.0   1.8 1.4   1.2 2.3   2.5 0.7   1.0 1.0   0.7 0.0   0.0 0.0   0.0

Nighttime Forecasts
Updated: 08-19-26 at 11:00 pm
Goal Forecast Day Day +1 Day +2 Day +3
± 2.0° F Low High Low High Low High Low High
Date NW Act WS NW Act WS NW Act WS NW Act WS NW Act WS NW Act WS NW Act WS NW Act WS
08-19-26 57   66 85   85 57   59 83   83 56   61 84   75 56   63 86   79
08-18-26 57 66.6 69 87 86.2 89 57   71 84   82 57   63 82   83 55   66 83   76
08-17-26 56 67.3 67 86 78.4 85 57 66.6 68 88 86.2 86 58   70 85   84 57   66 82   81
08-16-26 56 67.6 64 83 82.4 87 55 67.3 68 84 78.4 88 56 66.6 68 85 86.2 88 56   70 82   83
08-15-26 54 60.6 61 84 84.0 85 55 67.6 64 82 82.4 87 55 67.3 66 83 78.4 86 56 66.6 68 85 86.2 88
08-14-26 55 63.3 64 79 86.4 85 54 60.6 66 82 84.0 85 54 67.6 66 79 82.4 89 54 67.3 66 81 78.4 84
08-13-26 55 63.7 65 75 86.9 88 54 63.3 64 78 86.4 85 53 60.6 67 79 84.0 84 54 67.6 64 78 82.4 88
Results NW Act WS NW Act WS NW Act WS NW Act WS NW Act WS NW Act WS NW Act WS NW Act WS
# Succ 0 4 3 3 0 3 3 3 0 3 1 2 0 2 1 1
% Succ     66.7 50.0   50.0     60.0 60.0   60.0     75.0 25.0   50.0     66.7 33.3   33.3
Ave Error 9.4   1.5 4.7   2.9 10.1   2.4 3.6   3.4 11.0   2.7 3.6   4.0 12.5   2.1 2.7   4.3
Net Error -9.4   0.2 -1.7   2.5 -10.1   0.9 -0.7   2.7 -11.0   1.2 -1.3   4.0 -12.5   -1.2 -1.0   4.3
Std Dev 1.7   1.2 3.4   1.9 1.5   1.0 1.9   3.2 0.2   0.6 1.2   1.1 0.0   0.0 0.0   0.0