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).

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## 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 2020-03-05 00:00:05 2020   3   5    0   0  5.0004    280.6016      0.00628
## 2 2020-03-05 00:00:10 2020   3   5    0   0 10.0008    280.6615      0.00628
## 3 2020-03-05 00:00:15 2020   3   5    0   0 15.0012    280.7141      0.00628
## 4 2020-03-05 00:00:20 2020   3   5    0   0 20.0016    280.7614      0.00628
## 5 2020-03-05 00:00:24 2020   3   5    0   0 24.9984    280.8043      0.00628
## 6 2020-03-05 00:00:29 2020   3   5    0   0 29.9988    280.8441      0.00629
##    U_WIND  V_WIND Wind.Speed Wind.Direction Station
## 1 0.49444 4.90051   4.925390       185.7614     JFK
## 2 0.43015 4.64126   4.661150       185.2950     JFK
## 3 0.38830 4.45573   4.472617       184.9805     JFK
## 4 0.35770 4.30350   4.318340       184.7514     JFK
## 5 0.33539 4.18034   4.193773       184.5870     JFK
## 6 0.31931 4.07509   4.087581       184.4803     JFK
##             Date.Time year mon day hour min     sec Temperature Mixing.Ratio
## 1 2020-03-04 00:00:05 2020   3   4    0   0  5.0004    281.4672      0.00542
## 2 2020-03-04 00:00:10 2020   3   4    0   0 10.0008    281.4989      0.00543
## 3 2020-03-04 00:00:15 2020   3   4    0   0 15.0012    281.5237      0.00543
## 4 2020-03-04 00:00:20 2020   3   4    0   0 20.0016    281.5451      0.00543
## 5 2020-03-04 00:00:24 2020   3   4    0   0 24.9984    281.5676      0.00544
## 6 2020-03-04 00:00:29 2020   3   4    0   0 29.9988    281.5851      0.00544
##    U_WIND  V_WIND Wind.Speed Wind.Direction Station
## 1 1.22254 6.62521   6.737063       190.4551     JFK
## 2 1.09269 6.17132   6.267309       190.0407     JFK
## 3 1.01160 5.86766   5.954223       189.7818     JFK
## 4 0.94945 5.63086   5.710345       189.5709     JFK
## 5 0.90630 5.45183   5.526647       189.4384     JFK
## 6 0.87041 5.29583   5.366883       189.3336     JFK
##             Date.Time year mon day hour min     sec Temperature Mixing.Ratio
## 1 2020-03-03 00:00:05 2020   3   3    0   0  5.0004    281.4672      0.00542
## 2 2020-03-03 00:00:10 2020   3   3    0   0 10.0008    281.4989      0.00543
## 3 2020-03-03 00:00:15 2020   3   3    0   0 15.0012    281.5237      0.00543
## 4 2020-03-03 00:00:20 2020   3   3    0   0 20.0016    281.5451      0.00543
## 5 2020-03-03 00:00:24 2020   3   3    0   0 24.9984    281.5676      0.00544
## 6 2020-03-03 00:00:29 2020   3   3    0   0 29.9988    281.5851      0.00544
##    U_WIND  V_WIND Wind.Speed Wind.Direction Station
## 1 1.22254 6.62521   6.737063       190.4551     JFK
## 2 1.09269 6.17132   6.267309       190.0407     JFK
## 3 1.01160 5.86766   5.954223       189.7818     JFK
## 4 0.94945 5.63086   5.710345       189.5709     JFK
## 5 0.90630 5.45183   5.526647       189.4384     JFK
## 6 0.87041 5.29583   5.366883       189.3336     JFK
##   Station           Date.Time Temperature Relative.Humidity Wind.Direction
## 1     JFK 2020-03-04 00:00:00         NaN               NaN            200
## 2     JFK 2020-03-04 00:05:00         NaN               NaN            200
## 3     JFK 2020-03-04 00:10:00         NaN               NaN            NaN
## 4     JFK 2020-03-04 00:15:00         NaN               NaN            NaN
## 5     JFK 2020-03-04 00:20:00         NaN               NaN            NaN
## 6     JFK 2020-03-04 00:25:00         NaN               NaN            200
##   Wind.Speed year mon day hour min sec
## 1   7.201646 2020   3   4    0   0   0
## 2   7.716049 2020   3   4    0   5   0
## 3   7.716049 2020   3   4    0  10   0
## 4   8.230453 2020   3   4    0  15   0
## 5   7.716049 2020   3   4    0  20   0
## 6   7.716049 2020   3   4    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 1.415 2.242 2.091
2 WRF D-1 1.588 2.254 1.791
3 WRF D-2 -2.339 2.843 2.356
JFK - WRF 10-m Wind Speed (m/s) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 -0.532 3.064 2.598
2 WRF D-1 0.038 2.764 2.191
3 WRF D-2 -3.611 4.384 3.699
JFK - WRF 10-m Wind Direction (degN) Performance
Forecast.Init RMSE MAE
1 WRF D-0 67.874 63.978
2 WRF D-1 65.118 60.401
3 WRF D-2 32.439 24.341

Forecast Hour Evaluation for LGA

LGA - WRF 2-m Temperature (K) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 1.879 2.081 1.879
2 WRF D-1 1.685 2.525 1.983
3 WRF D-2 -1.891 2.316 1.968
LGA - WRF 10-m Wind Speed (m/s) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 -2.655 3.682 3.203
2 WRF D-1 -2.523 3.534 3.061
3 WRF D-2 -3.929 4.558 4.012
LGA - WRF 10-m Wind Direction (degN) Performance
Forecast.Init RMSE MAE
1 WRF D-0 62.806 57.651
2 WRF D-1 61.395 55.888
3 WRF D-2 33.497 25.042

Forecast Hour Evaluation for NYC

NYC - WRF 2-m Temperature (K) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 2.038 2.158 2.038
2 WRF D-1 1.737 2.546 2.010
3 WRF D-2 -1.561 2.003 1.668
NYC - WRF 10-m Wind Speed (m/s) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 -1.575 2.248 1.898
2 WRF D-1 -1.521 2.173 1.845
3 WRF D-2 -1.936 2.507 2.189
NYC - WRF 10-m Wind Direction (degN) Performance
Forecast.Init RMSE MAE
1 WRF D-0 71.577 65.330
2 WRF D-1 70.147 62.232
3 WRF D-2 46.559 28.228

uWRF and ASOS Time-Series Visualization

Temperature

Wind Speed

Wind Direction