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 2020-07-26 00:00:05 2020   7  26    0   0  5.0004    299.7292      0.01889
## 2 2020-07-26 00:00:10 2020   7  26    0   0 10.0008    299.8017      0.01889
## 3 2020-07-26 00:00:15 2020   7  26    0   0 15.0012    299.8618      0.01889
## 4 2020-07-26 00:00:20 2020   7  26    0   0 20.0016    299.9129      0.01889
## 5 2020-07-26 00:00:24 2020   7  26    0   0 24.9984    299.9566      0.01889
## 6 2020-07-26 00:00:29 2020   7  26    0   0 29.9988    299.9955      0.01889
##    U_WIND  V_WIND Wind.Speed Wind.Direction Station
## 1 0.90864 4.83350   4.918165       190.6467     JFK
## 2 0.83358 4.60276   4.677634       190.2653     JFK
## 3 0.78935 4.43366   4.503378       190.0949     JFK
## 4 0.75183 4.29829   4.363547       189.9215     JFK
## 5 0.72729 4.18675   4.249450       189.8546     JFK
## 6 0.70042 4.09501   4.154479       189.7061     JFK
##             Date.Time year mon day hour min     sec Temperature Mixing.Ratio
## 1 2020-07-25 00:00:05 2020   7  25    0   0  5.0004    297.8785      0.01777
## 2 2020-07-25 00:00:10 2020   7  25    0   0 10.0008    297.8979      0.01777
## 3 2020-07-25 00:00:15 2020   7  25    0   0 15.0012    297.9153      0.01777
## 4 2020-07-25 00:00:20 2020   7  25    0   0 20.0016    297.9312      0.01777
## 5 2020-07-25 00:00:24 2020   7  25    0   0 24.9984    297.9457      0.01776
## 6 2020-07-25 00:00:29 2020   7  25    0   0 29.9988    297.9628      0.01777
##     U_WIND  V_WIND Wind.Speed Wind.Direction Station
## 1 -0.19366 0.90123  0.9218024       167.8725     JFK
## 2 -0.19436 0.89258  0.9134960       167.7156     JFK
## 3 -0.18742 0.89084  0.9103418       168.1191     JFK
## 4 -0.19043 0.88544  0.9056862       167.8624     JFK
## 5 -0.18519 0.87600  0.8953610       168.0632     JFK
## 6 -0.18203 0.86297  0.8819593       168.0890     JFK
##             Date.Time year mon day hour min     sec Temperature Mixing.Ratio
## 1 2020-07-24 00:00:05 2020   7  24    0   0  5.0004    300.0473      0.02035
## 2 2020-07-24 00:00:10 2020   7  24    0   0 10.0008    300.1220      0.02035
## 3 2020-07-24 00:00:15 2020   7  24    0   0 15.0012    300.1868      0.02035
## 4 2020-07-24 00:00:20 2020   7  24    0   0 20.0016    300.2448      0.02035
## 5 2020-07-24 00:00:24 2020   7  24    0   0 24.9984    300.2970      0.02035
## 6 2020-07-24 00:00:29 2020   7  24    0   0 29.9988    300.3450      0.02035
##    U_WIND  V_WIND Wind.Speed Wind.Direction Station
## 1 0.77760 3.93313   4.009261       191.1834     JFK
## 2 0.72123 3.74954   3.818275       190.8880     JFK
## 3 0.67933 3.61670   3.679947       190.6380     JFK
## 4 0.64965 3.50353   3.563252       190.5049     JFK
## 5 0.62527 3.40992   3.466773       190.3908     JFK
## 6 0.60323 3.32908   3.383291       190.2706     JFK
##   Station           Date.Time Temperature Relative.Humidity Wind.Direction
## 1     JFK 2020-07-25 00:00:00         NaN               NaN            160
## 2     JFK 2020-07-25 00:05:00         NaN               NaN            160
## 3     JFK 2020-07-25 00:10:00         NaN               NaN            160
## 4     JFK 2020-07-25 00:15:00         NaN               NaN            160
## 5     JFK 2020-07-25 00:20:00         NaN               NaN            160
## 6     JFK 2020-07-25 00:25:00         NaN               NaN            150
##   Wind.Speed year mon day hour min sec
## 1   2.572016 2020   7  25    0   0   0
## 2   2.057613 2020   7  25    0   5   0
## 3   1.028807 2020   7  25    0  10   0
## 4   2.057613 2020   7  25    0  15   0
## 5   2.057613 2020   7  25    0  20   0
## 6   2.057613 2020   7  25    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 0.199 1.714 1.203
2 WRF D-1 -0.022 1.282 0.964
3 WRF D-2 -0.763 1.857 1.371
JFK - WRF 10-m Wind Speed (m/s) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 -1.242 2.017 1.705
2 WRF D-1 -1.043 2.239 1.957
3 WRF D-2 -0.815 1.968 1.759
JFK - WRF 10-m Wind Direction (degN) Performance
Forecast.Init RMSE MAE
1 WRF D-0 29.024 19.025
2 WRF D-1 32.758 24.933
3 WRF D-2 36.046 28.860

Forecast Hour Evaluation for LGA

LGA - WRF 2-m Temperature (K) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 -0.573 1.413 1.306
2 WRF D-1 -1.382 1.561 1.382
3 WRF D-2 -1.262 1.694 1.334
LGA - WRF 10-m Wind Speed (m/s) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 -2.239 2.567 2.272
2 WRF D-1 -2.115 2.453 2.175
3 WRF D-2 -2.119 2.515 2.206
LGA - WRF 10-m Wind Direction (degN) Performance
Forecast.Init RMSE MAE
1 WRF D-0 27.348 20.174
2 WRF D-1 28.179 23.177
3 WRF D-2 22.605 18.548

Forecast Hour Evaluation for NYC

NYC - WRF 2-m Temperature (K) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 2.114 2.542 2.114
2 WRF D-1 1.107 1.383 1.107
3 WRF D-2 1.221 1.754 1.308
NYC - WRF 10-m Wind Speed (m/s) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 -1.545 1.777 1.624
2 WRF D-1 -1.589 1.809 1.687
3 WRF D-2 -1.563 1.810 1.666
NYC - WRF 10-m Wind Direction (degN) Performance
Forecast.Init RMSE MAE
1 WRF D-0 25.762 20.101
2 WRF D-1 41.806 28.777
3 WRF D-2 49.002 34.607

uWRF and ASOS Time-Series Visualization

Temperature

## Warning: Removed 292 rows containing missing values (geom_point).
## Warning: Removed 292 rows containing missing values (geom_path).

Wind Speed

Wind Direction