Introduction

In this document I will explore how to create the first part of the evaluation system I proposed. The working title of this is the “Forecast-Hour Evaluation.” The idea here is that we are looking at the performance of the model by looking at how it performed with different start times (using the most recent 00-hr forecast as input).

## Warning in rgl.init(initValue, onlyNULL): RGL: unable to open X11 display
## Warning: 'rgl.init' failed, running with 'rgl.useNULL = TRUE'.

Read Model and Observation Data

Read WRF Data

For this evaluation system we need to look at three different output folders. Here we use the folders named, forecast_day_minus_0, forecast_day_minus_1, forecast_day_minus_2. The contents of each of these folders will be similar: wrfout files for 86 forecast hours and time-series data for different locations of interest. Here we will first read the forecast data.

Read the OBS Data

Now we will read the observation data from the ASOS stations. The script that downloads the data is in ./obs_station_day_minus_0/dl_ny_asos.py. The lines for the dates to download need to be changed before running it. Once the files are download, the lines below reads the data and adds column names.

Unit Conversion

Model and observation data do not share the same units for the same variable. For temperature, WRF is in Kelvin and ASOS is in degreesF. For winds, WRF is in m/s and ASOS is in knots. The formulas used to convert the numbers to a common system is shown here. For temperature I will use Kelvin, and m/s for wind speeds.

Combined Data Frames

Now we have one data frame for all the observations, and three (3) data frames of the WRF data (one data frame per forecast init time). The lines below provide a visual of the data frames.

##             Date.Time year mon day hour min     sec Temperature Mixing.Ratio
## 1 2020-04-25 00:00:05 2020   4  25    0   0  5.0004    282.3018      0.00654
## 2 2020-04-25 00:00:10 2020   4  25    0   0 10.0008    282.3226      0.00654
## 3 2020-04-25 00:00:15 2020   4  25    0   0 15.0012    282.3431      0.00655
## 4 2020-04-25 00:00:20 2020   4  25    0   0 20.0016    282.3626      0.00655
## 5 2020-04-25 00:00:24 2020   4  25    0   0 24.9984    282.3819      0.00655
## 6 2020-04-25 00:00:29 2020   4  25    0   0 29.9988    282.4017      0.00655
##     U_WIND   V_WIND Wind.Speed Wind.Direction Station
## 1 -0.64592 -2.57242   2.652274       14.09524     JFK
## 2 -0.62324 -2.49231   2.569054       14.03976     JFK
## 3 -0.59594 -2.42148   2.493734       13.82605     JFK
## 4 -0.57400 -2.36096   2.429734       13.66472     JFK
## 5 -0.55576 -2.30793   2.373902       13.53931     JFK
## 6 -0.54057 -2.25693   2.320765       13.46949     JFK
##             Date.Time year mon day hour min     sec Temperature Mixing.Ratio
## 1 2020-04-24 00:00:05 2020   4  24    0   0  5.0004    280.4555      0.00353
## 2 2020-04-24 00:00:10 2020   4  24    0   0 10.0008    280.5028      0.00354
## 3 2020-04-24 00:00:15 2020   4  24    0   0 15.0012    280.5467      0.00354
## 4 2020-04-24 00:00:20 2020   4  24    0   0 20.0016    280.5885      0.00354
## 5 2020-04-24 00:00:24 2020   4  24    0   0 24.9984    280.6281      0.00355
## 6 2020-04-24 00:00:29 2020   4  24    0   0 29.9988    280.6665      0.00355
##     U_WIND  V_WIND Wind.Speed Wind.Direction Station
## 1 -1.80493 1.52667   2.363999       130.2257     JFK
## 2 -1.78325 1.50036   2.330464       130.0760     JFK
## 3 -1.77260 1.48220   2.310634       129.9015     JFK
## 4 -1.75523 1.45845   2.282084       129.7238     JFK
## 5 -1.74314 1.43608   2.258509       129.4833     JFK
## 6 -1.72932 1.41137   2.232154       129.2193     JFK
##             Date.Time year mon day hour min     sec Temperature Mixing.Ratio
## 1 2020-04-23 00:00:05 2020   4  23    0   0  5.0004    282.3331       0.0028
## 2 2020-04-23 00:00:10 2020   4  23    0   0 10.0008    282.3642       0.0028
## 3 2020-04-23 00:00:15 2020   4  23    0   0 15.0012    282.3939       0.0028
## 4 2020-04-23 00:00:20 2020   4  23    0   0 20.0016    282.4206       0.0028
## 5 2020-04-23 00:00:24 2020   4  23    0   0 24.9984    282.4457       0.0028
## 6 2020-04-23 00:00:29 2020   4  23    0   0 29.9988    282.4695       0.0028
##    U_WIND   V_WIND Wind.Speed Wind.Direction Station
## 1 4.32144 -1.58800   4.603975       290.1769     JFK
## 2 4.25332 -1.56723   4.532873       290.2274     JFK
## 3 4.19032 -1.53611   4.463005       290.1322     JFK
## 4 4.13571 -1.51886   4.405795       290.1660     JFK
## 5 4.08334 -1.50069   4.350372       290.1792     JFK
## 6 4.02980 -1.48409   4.294393       290.2177     JFK
##   Station           Date.Time Temperature Relative.Humidity Wind.Direction
## 1     JFK 2020-04-24 00:00:00         NaN               NaN            130
## 2     JFK 2020-04-24 00:05:00         NaN               NaN            120
## 3     JFK 2020-04-24 00:10:00         NaN               NaN            120
## 4     JFK 2020-04-24 00:15:00         NaN               NaN            140
## 5     JFK 2020-04-24 00:20:00         NaN               NaN            130
## 6     JFK 2020-04-24 00:25:00         NaN               NaN            120
##   Wind.Speed year mon day hour min sec
## 1   2.572016 2020   4  24    0   0   0
## 2   2.572016 2020   4  24    0   5   0
## 3   1.028807 2020   4  24    0  10   0
## 4   2.572016 2020   4  24    0  15   0
## 5   2.572016 2020   4  24    0  20   0
## 6   2.057613 2020   4  24    0  25   0

Locations for Plots

Match Times for Model and Observations

Select Day of Interest

Time-matching is performed using a routine that can be found in Analysis01-Time_Matching_Problem.Rmd. The time matching will be done per variable. For the Forecast-Hour Evaluation product, we will focus on the temperature, wind speed and wind direction variables. Also, now that we have read all the TS data and ASOS data, we need to extract the day of interest, or doi for the time-series.

Note that for this product the “day of interest” will always be the UTC date of the day before.

We now have filtered data frames for the observations and model data for the day of interest.

Next, we will select only the temperature data for comparing the model and observations. This needs to be done on a per station basis. Note that we use the function drop_na() to drop rows which contain NaN or NA data. Since each variable is measured at different intervals, not all variables will have data available at every time step in the ASOS data. The functions may be too sensitive to missing data and thus we take care to remvove it here from the observations, after we have isolated a particular variable.

Temperature Time-Matching

Location: JFK

Location: LGA

Location: NYC

Wind Speed Time-Matching

Location: JFK

Location: LGA

Location: NYC

Wind Direction Time-Matching

Location: JFK

Location: LGA

Location: NYC

Forecast Hour Evaluation for JFK

For the temperature data I will use Bias, RMSE and MAE for the comparison statistics

JFK - WRF 2-m Temperature (K) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 1.224 1.938 1.628
2 WRF D-1 0.910 1.456 1.187
3 WRF D-2 0.015 1.257 1.076
JFK - WRF 10-m Wind Speed (m/s) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 -0.264 1.226 1.029
2 WRF D-1 -0.433 1.459 1.165
3 WRF D-2 0.433 1.350 1.136
JFK - WRF 10-m Wind Direction (degN) Performance
Forecast.Init RMSE MAE
1 WRF D-0 24.589 16.309
2 WRF D-1 43.276 29.413
3 WRF D-2 27.670 20.040

Forecast Hour Evaluation for LGA

LGA - WRF 2-m Temperature (K) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 0.710 1.188 1.059
2 WRF D-1 0.131 0.982 0.840
3 WRF D-2 -0.589 1.116 0.861
LGA - WRF 10-m Wind Speed (m/s) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 -0.875 1.815 1.382
2 WRF D-1 -0.934 1.951 1.502
3 WRF D-2 -0.219 1.873 1.531
LGA - WRF 10-m Wind Direction (degN) Performance
Forecast.Init RMSE MAE
1 WRF D-0 46.370 31.312
2 WRF D-1 51.193 40.494
3 WRF D-2 30.584 22.654

Forecast Hour Evaluation for NYC

NYC - WRF 2-m Temperature (K) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 1.195 1.594 1.364
2 WRF D-1 0.895 1.702 1.557
3 WRF D-2 0.063 0.901 0.729
NYC - WRF 10-m Wind Speed (m/s) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 -0.463 1.289 0.920
2 WRF D-1 -0.468 1.303 0.952
3 WRF D-2 -0.359 1.240 0.951
NYC - WRF 10-m Wind Direction (degN) Performance
Forecast.Init RMSE MAE
1 WRF D-0 25.600 24.187
2 WRF D-1 44.530 38.800
3 WRF D-2 35.958 26.669

uWRF and ASOS Time-Series Visualization

Temperature

## Warning: Removed 26 rows containing missing values (geom_point).

Wind Speed

Wind Direction