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
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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 2020-07-21 00:00:05 2020   7  21    0   0  5.0004    303.7483      0.01567
## 2 2020-07-21 00:00:10 2020   7  21    0   0 10.0008    303.7796      0.01567
## 3 2020-07-21 00:00:15 2020   7  21    0   0 15.0012    303.8073      0.01567
## 4 2020-07-21 00:00:20 2020   7  21    0   0 20.0016    303.8313      0.01567
## 5 2020-07-21 00:00:24 2020   7  21    0   0 24.9984    303.8523      0.01567
## 6 2020-07-21 00:00:29 2020   7  21    0   0 29.9988    303.8714      0.01567
##    U_WIND   V_WIND Wind.Speed Wind.Direction Station
## 1 3.47407 -0.59788   3.525142       279.7648     JFK
## 2 3.42218 -0.58846   3.472406       279.7569     JFK
## 3 3.37524 -0.57717   3.424233       279.7038     JFK
## 4 3.33204 -0.56788   3.380086       279.6720     JFK
## 5 3.29009 -0.55644   3.336813       279.5994     JFK
## 6 3.24839 -0.54384   3.293600       279.5042     JFK
##             Date.Time year mon day hour min     sec Temperature Mixing.Ratio
## 1 2020-07-20 00:00:05 2020   7  20    0   0  5.0004    298.9888      0.01875
## 2 2020-07-20 00:00:10 2020   7  20    0   0 10.0008    299.1123      0.01875
## 3 2020-07-20 00:00:15 2020   7  20    0   0 15.0012    299.2151      0.01875
## 4 2020-07-20 00:00:20 2020   7  20    0   0 20.0016    299.3042      0.01875
## 5 2020-07-20 00:00:24 2020   7  20    0   0 24.9984    299.3829      0.01874
## 6 2020-07-20 00:00:29 2020   7  20    0   0 29.9988    299.4472      0.01874
##     U_WIND  V_WIND Wind.Speed Wind.Direction Station
## 1  0.11679 6.50548   6.506528       181.0285     JFK
## 2  0.02975 6.10297   6.103043       180.2793     JFK
## 3 -0.02853 5.82294   5.823010       179.7193     JFK
## 4 -0.07052 5.60088   5.601324       179.2786     JFK
## 5 -0.09859 5.41937   5.420267       178.9578     JFK
## 6 -0.11801 5.27576   5.277080       178.7186     JFK
##             Date.Time year mon day hour min     sec Temperature Mixing.Ratio
## 1 2020-07-19 00:00:05 2020   7  19    0   0  5.0004    298.5450      0.01776
## 2 2020-07-19 00:00:10 2020   7  19    0   0 10.0008    298.6396      0.01776
## 3 2020-07-19 00:00:15 2020   7  19    0   0 15.0012    298.7230      0.01776
## 4 2020-07-19 00:00:20 2020   7  19    0   0 20.0016    298.7982      0.01776
## 5 2020-07-19 00:00:24 2020   7  19    0   0 24.9984    298.8667      0.01776
## 6 2020-07-19 00:00:29 2020   7  19    0   0 29.9988    298.9297      0.01775
##    U_WIND  V_WIND Wind.Speed Wind.Direction Station
## 1 0.40536 3.72305   3.745052       186.2138     JFK
## 2 0.36550 3.56774   3.586413       185.8493     JFK
## 3 0.33498 3.45794   3.474127       185.5331     JFK
## 4 0.30943 3.35717   3.371400       185.2661     JFK
## 5 0.28847 3.26732   3.280030       185.0455     JFK
## 6 0.27264 3.19378   3.205396       184.8793     JFK
##   Station           Date.Time Temperature Relative.Humidity Wind.Direction
## 1     JFK 2020-07-20 00:00:00         NaN               NaN            190
## 2     JFK 2020-07-20 00:05:00         NaN               NaN            180
## 3     JFK 2020-07-20 00:10:00         NaN               NaN            180
## 4     JFK 2020-07-20 00:15:00         NaN               NaN            180
## 5     JFK 2020-07-20 00:20:00         NaN               NaN            180
## 6     JFK 2020-07-20 00:25:00         NaN               NaN            180
##   Wind.Speed year mon day hour min sec
## 1   9.773663 2020   7  20    0   0   0
## 2   8.230453 2020   7  20    0   5   0
## 3   8.744856 2020   7  20    0  10   0
## 4   8.744856 2020   7  20    0  15   0
## 5   8.230453 2020   7  20    0  20   0
## 6   9.773663 2020   7  20    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 -0.080 1.267 1.006
2 WRF D-1 -0.046 0.723 0.598
3 WRF D-2 -0.756 1.183 0.947
JFK - WRF 10-m Wind Speed (m/s) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 -1.109 1.925 1.477
2 WRF D-1 -0.787 1.591 1.207
3 WRF D-2 -0.734 1.493 1.182
JFK - WRF 10-m Wind Direction (degN) Performance
Forecast.Init RMSE MAE
1 WRF D-0 46.158 28.033
2 WRF D-1 45.723 34.427
3 WRF D-2 54.222 35.154

Forecast Hour Evaluation for LGA

LGA - WRF 2-m Temperature (K) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 -0.158 1.101 0.950
2 WRF D-1 -0.755 1.426 1.203
3 WRF D-2 -1.381 1.672 1.466
LGA - WRF 10-m Wind Speed (m/s) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 -1.731 2.363 1.906
2 WRF D-1 -1.464 2.187 1.651
3 WRF D-2 -1.286 2.072 1.598
LGA - WRF 10-m Wind Direction (degN) Performance
Forecast.Init RMSE MAE
1 WRF D-0 54.067 45.399
2 WRF D-1 72.216 59.511
3 WRF D-2 60.762 47.414

Forecast Hour Evaluation for NYC

NYC - WRF 2-m Temperature (K) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 2.296 2.436 2.296
2 WRF D-1 1.309 1.947 1.529
3 WRF D-2 0.967 1.794 1.411
NYC - WRF 10-m Wind Speed (m/s) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 -0.095 0.962 0.878
2 WRF D-1 -0.080 0.982 0.903
3 WRF D-2 0.061 0.904 0.844
NYC - WRF 10-m Wind Direction (degN) Performance
Forecast.Init RMSE MAE
1 WRF D-0 81.179 59.573
2 WRF D-1 69.171 56.022
3 WRF D-2 51.302 38.358

uWRF and ASOS Time-Series Visualization

Temperature

## Warning: Removed 284 rows containing missing values (geom_point).
## Warning: Removed 284 rows containing missing values (geom_path).

Wind Speed

Wind Direction