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 2020-07-22 00:00:05 2020   7  22    0   0  5.0004    299.2834       0.0164
## 2 2020-07-22 00:00:10 2020   7  22    0   0 10.0008    299.3737       0.0164
## 3 2020-07-22 00:00:15 2020   7  22    0   0 15.0012    299.4538       0.0164
## 4 2020-07-22 00:00:20 2020   7  22    0   0 20.0016    299.5265       0.0164
## 5 2020-07-22 00:00:24 2020   7  22    0   0 24.9984    299.5924       0.0164
## 6 2020-07-22 00:00:29 2020   7  22    0   0 29.9988    299.6529       0.0164
##     U_WIND  V_WIND Wind.Speed Wind.Direction Station
## 1 -0.30280 3.51635   3.529363       175.0783     JFK
## 2 -0.32375 3.37883   3.394305       174.5268     JFK
## 3 -0.33964 3.27984   3.297379       174.0879     JFK
## 4 -0.35301 3.18158   3.201104       173.6687     JFK
## 5 -0.36535 3.10078   3.122230       173.2801     JFK
## 6 -0.37027 3.02515   3.047726       173.0219     JFK
##             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
##   Station           Date.Time Temperature Relative.Humidity Wind.Direction
## 1     JFK 2020-07-21 00:00:00         NaN               NaN            280
## 2     JFK 2020-07-21 00:05:00         NaN               NaN            280
## 3     JFK 2020-07-21 00:10:00         NaN               NaN            280
## 4     JFK 2020-07-21 00:15:00         NaN               NaN            280
## 5     JFK 2020-07-21 00:20:00         NaN               NaN            270
## 6     JFK 2020-07-21 00:25:00         NaN               NaN            270
##   Wind.Speed year mon day hour min sec
## 1   5.658436 2020   7  21    0   0   0
## 2   5.144033 2020   7  21    0   5   0
## 3   7.716049 2020   7  21    0  10   0
## 4   5.658436 2020   7  21    0  15   0
## 5   6.687243 2020   7  21    0  20   0
## 6   6.687243 2020   7  21    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 0.261 1.764 1.432
2 WRF D-1 -0.264 1.857 1.465
3 WRF D-2 -0.549 2.166 1.691
JFK - WRF 10-m Wind Speed (m/s) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 -0.708 2.265 1.460
2 WRF D-1 -0.686 2.310 1.387
3 WRF D-2 0.238 2.237 1.717
JFK - WRF 10-m Wind Direction (degN) Performance
Forecast.Init RMSE MAE
1 WRF D-0 63.113 47.290
2 WRF D-1 55.984 42.492
3 WRF D-2 67.241 57.490

Forecast Hour Evaluation for LGA

LGA - WRF 2-m Temperature (K) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 0.541 2.129 1.656
2 WRF D-1 -0.014 2.370 1.686
3 WRF D-2 -1.747 2.821 2.250
LGA - WRF 10-m Wind Speed (m/s) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 -1.695 2.437 2.009
2 WRF D-1 -1.884 2.535 2.130
3 WRF D-2 -1.256 2.305 1.757
LGA - WRF 10-m Wind Direction (degN) Performance
Forecast.Init RMSE MAE
1 WRF D-0 72.082 52.534
2 WRF D-1 60.758 44.778
3 WRF D-2 78.870 63.515

Forecast Hour Evaluation for NYC

NYC - WRF 2-m Temperature (K) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 3.309 4.175 3.309
2 WRF D-1 2.066 3.737 2.475
3 WRF D-2 0.545 2.260 1.930
NYC - WRF 10-m Wind Speed (m/s) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 -0.509 1.999 1.247
2 WRF D-1 -0.578 1.976 1.250
3 WRF D-2 -0.442 1.961 1.275
NYC - WRF 10-m Wind Direction (degN) Performance
Forecast.Init RMSE MAE
1 WRF D-0 118.540 104.458
2 WRF D-1 104.685 91.478
3 WRF D-2 89.593 81.284

uWRF and ASOS Time-Series Visualization

Temperature

## Warning: Removed 344 rows containing missing values (geom_point).
## Warning: Removed 344 rows containing missing values (geom_path).

Wind Speed

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

Wind Direction