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 2020-04-12 00:00:05 2020   4  12    0   0  5.0004    283.3337      0.00385
## 2 2020-04-12 00:00:10 2020   4  12    0   0 10.0008    283.3686      0.00385
## 3 2020-04-12 00:00:15 2020   4  12    0   0 15.0012    283.4007      0.00385
## 4 2020-04-12 00:00:20 2020   4  12    0   0 20.0016    283.4303      0.00385
## 5 2020-04-12 00:00:24 2020   4  12    0   0 24.9984    283.4584      0.00385
## 6 2020-04-12 00:00:29 2020   4  12    0   0 29.9988    283.4852      0.00385
##    U_WIND   V_WIND Wind.Speed Wind.Direction Station
## 1 3.28792 -0.19474   3.293682       273.3896     JFK
## 2 3.25129 -0.19964   3.257414       273.5137     JFK
## 3 3.21695 -0.19682   3.222965       273.5011     JFK
## 4 3.18527 -0.19884   3.191470       273.5720     JFK
## 5 3.15717 -0.19967   3.163478       273.6188     JFK
## 6 3.13000 -0.19681   3.136181       273.5979     JFK
##             Date.Time year mon day hour min     sec Temperature Mixing.Ratio
## 1 2020-04-11 00:00:05 2020   4  11    0   0  5.0004    280.5398      0.00371
## 2 2020-04-11 00:00:10 2020   4  11    0   0 10.0008    280.6251      0.00371
## 3 2020-04-11 00:00:15 2020   4  11    0   0 15.0012    280.7003      0.00371
## 4 2020-04-11 00:00:20 2020   4  11    0   0 20.0016    280.7659      0.00371
## 5 2020-04-11 00:00:24 2020   4  11    0   0 24.9984    280.8237      0.00371
## 6 2020-04-11 00:00:29 2020   4  11    0   0 29.9988    280.8758      0.00371
##    U_WIND   V_WIND Wind.Speed Wind.Direction Station
## 1 7.14118 -4.58683   8.487371       302.7129     JFK
## 2 6.90254 -4.41104   8.191601       302.5804     JFK
## 3 6.71820 -4.25757   7.953686       302.3639     JFK
## 4 6.55442 -4.13071   7.747463       302.2198     JFK
## 5 6.40317 -4.01794   7.559393       302.1080     JFK
## 6 6.25332 -3.91227   7.376304       302.0314     JFK
##             Date.Time year mon day hour min     sec Temperature Mixing.Ratio
## 1 2020-04-10 00:00:05 2020   4  10    0   0  5.0004    283.8201      0.00691
## 2 2020-04-10 00:00:10 2020   4  10    0   0 10.0008    283.9124      0.00691
## 3 2020-04-10 00:00:15 2020   4  10    0   0 15.0012    283.9962      0.00691
## 4 2020-04-10 00:00:20 2020   4  10    0   0 20.0016    284.0736      0.00691
## 5 2020-04-10 00:00:24 2020   4  10    0   0 24.9984    284.1458      0.00691
## 6 2020-04-10 00:00:29 2020   4  10    0   0 29.9988    284.2134      0.00692
##     U_WIND  V_WIND Wind.Speed Wind.Direction Station
## 1 -0.57875 2.32576   2.396688       166.0261     JFK
## 2 -0.57692 2.26299   2.335372       165.6978     JFK
## 3 -0.57382 2.22165   2.294558       165.5178     JFK
## 4 -0.57045 2.17530   2.248854       165.3057     JFK
## 5 -0.56632 2.13857   2.212284       165.1678     JFK
## 6 -0.56016 2.10459   2.177861       165.0956     JFK
##   Station           Date.Time Temperature Relative.Humidity Wind.Direction
## 1     JFK 2020-04-11 00:00:00         NaN               NaN            NaN
## 2     JFK 2020-04-11 00:05:00         NaN               NaN            290
## 3     JFK 2020-04-11 00:10:00         NaN               NaN            300
## 4     JFK 2020-04-11 00:15:00         NaN               NaN            NaN
## 5     JFK 2020-04-11 00:20:00         NaN               NaN            300
## 6     JFK 2020-04-11 00:25:00         NaN               NaN            NaN
##   Wind.Speed year mon day hour min sec
## 1   9.259259 2020   4  11    0   0   0
## 2   8.744856 2020   4  11    0   5   0
## 3   9.259259 2020   4  11    0  10   0
## 4  11.831276 2020   4  11    0  15   0
## 5  11.316872 2020   4  11    0  20   0
## 6   9.773663 2020   4  11    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 0.552 1.709 1.428
2 WRF D-1 0.315 1.538 1.180
3 WRF D-2 -3.363 3.917 3.363
JFK - WRF 10-m Wind Speed (m/s) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 -1.419 2.093 1.723
2 WRF D-1 -1.236 2.131 1.680
3 WRF D-2 1.185 3.256 2.695
JFK - WRF 10-m Wind Direction (degN) Performance
Forecast.Init RMSE MAE
1 WRF D-0 47.849 30.604
2 WRF D-1 55.138 34.542
3 WRF D-2 122.516 109.307

Forecast Hour Evaluation for LGA

LGA - WRF 2-m Temperature (K) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 0.102 1.231 0.915
2 WRF D-1 -0.553 1.382 1.175
3 WRF D-2 -5.206 5.380 5.206
LGA - WRF 10-m Wind Speed (m/s) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 -2.524 3.044 2.620
2 WRF D-1 -2.330 2.788 2.446
3 WRF D-2 -1.480 2.784 2.375
LGA - WRF 10-m Wind Direction (degN) Performance
Forecast.Init RMSE MAE
1 WRF D-0 44.582 28.317
2 WRF D-1 64.848 44.493
3 WRF D-2 118.300 104.666

Forecast Hour Evaluation for NYC

NYC - WRF 2-m Temperature (K) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 0.516 1.554 1.331
2 WRF D-1 -0.200 1.267 0.993
3 WRF D-2 -5.529 5.751 5.529
NYC - WRF 10-m Wind Speed (m/s) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 -1.592 2.045 1.741
2 WRF D-1 -1.523 1.940 1.655
3 WRF D-2 -1.419 1.991 1.653
NYC - WRF 10-m Wind Direction (degN) Performance
Forecast.Init RMSE MAE
1 WRF D-0 61.232 45.450
2 WRF D-1 66.425 42.111
3 WRF D-2 121.262 111.603

uWRF and ASOS Time-Series Visualization

Temperature

## Warning: Removed 2 rows containing missing values (geom_point).

Wind Speed

Wind Direction