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 2020-03-29 00:00:05 2020   3  29    0   0  5.0004    281.5700      0.00643
## 2 2020-03-29 00:00:10 2020   3  29    0   0 10.0008    281.6098      0.00644
## 3 2020-03-29 00:00:15 2020   3  29    0   0 15.0012    281.6478      0.00644
## 4 2020-03-29 00:00:20 2020   3  29    0   0 20.0016    281.6833      0.00644
## 5 2020-03-29 00:00:24 2020   3  29    0   0 24.9984    281.7169      0.00644
## 6 2020-03-29 00:00:29 2020   3  29    0   0 29.9988    281.7498      0.00645
##     U_WIND   V_WIND Wind.Speed Wind.Direction Station
## 1 -4.96307 -1.92827   5.324499       68.76768     JFK
## 2 -4.84700 -1.80931   5.173685       69.53018     JFK
## 3 -4.75221 -1.72211   5.054618       70.08045     JFK
## 4 -4.66448 -1.65323   4.948792       70.48416     JFK
## 5 -4.57720 -1.59935   4.848575       70.73973     JFK
## 6 -4.49558 -1.54968   4.755181       70.98032     JFK
##             Date.Time year mon day hour min     sec Temperature Mixing.Ratio
## 1 2020-03-28 00:00:05 2020   3  28    0   0  5.0004    284.4556      0.00539
## 2 2020-03-28 00:00:10 2020   3  28    0   0 10.0008    284.5055      0.00539
## 3 2020-03-28 00:00:15 2020   3  28    0   0 15.0012    284.5514      0.00539
## 4 2020-03-28 00:00:20 2020   3  28    0   0 20.0016    284.5932      0.00540
## 5 2020-03-28 00:00:24 2020   3  28    0   0 24.9984    284.6317      0.00540
## 6 2020-03-28 00:00:29 2020   3  28    0   0 29.9988    284.6685      0.00540
##     U_WIND  V_WIND Wind.Speed Wind.Direction Station
## 1 -0.08000 1.89402   1.895709       177.5814     JFK
## 2 -0.08732 1.85627   1.858323       177.3068     JFK
## 3 -0.09732 1.81876   1.821362       176.9371     JFK
## 4 -0.10869 1.78067   1.783984       176.5071     JFK
## 5 -0.11899 1.75000   1.754041       176.1102     JFK
## 6 -0.11969 1.72665   1.730793       176.0346     JFK
##             Date.Time year mon day hour min     sec Temperature Mixing.Ratio
## 1 2020-03-27 00:00:05 2020   3  27    0   0  5.0004    280.3574      0.00525
## 2 2020-03-27 00:00:10 2020   3  27    0   0 10.0008    280.4142      0.00525
## 3 2020-03-27 00:00:15 2020   3  27    0   0 15.0012    280.4645      0.00525
## 4 2020-03-27 00:00:20 2020   3  27    0   0 20.0016    280.5093      0.00526
## 5 2020-03-27 00:00:24 2020   3  27    0   0 24.9984    280.5502      0.00526
## 6 2020-03-27 00:00:29 2020   3  27    0   0 29.9988    280.5884      0.00526
##     U_WIND  V_WIND Wind.Speed Wind.Direction Station
## 1  0.06529 4.98872   4.989147       180.7498     JFK
## 2  0.01592 4.75248   4.752507       180.1919     JFK
## 3 -0.01840 4.57917   4.579207       179.7698     JFK
## 4 -0.04371 4.44076   4.440975       179.4361     JFK
## 5 -0.05924 4.32888   4.329285       179.2160     JFK
## 6 -0.06935 4.23352   4.234088       179.0615     JFK
##   Station           Date.Time Temperature Relative.Humidity Wind.Direction
## 1     JFK 2020-03-28 00:00:00         NaN               NaN            220
## 2     JFK 2020-03-28 00:05:00         NaN               NaN            230
## 3     JFK 2020-03-28 00:10:00         NaN               NaN            220
## 4     JFK 2020-03-28 00:15:00         NaN               NaN            210
## 5     JFK 2020-03-28 00:20:00         NaN               NaN            220
## 6     JFK 2020-03-28 00:25:00         NaN               NaN            200
##   Wind.Speed year mon day hour min sec
## 1   2.572016 2020   3  28    0   0   0
## 2   2.057613 2020   3  28    0   5   0
## 3   2.057613 2020   3  28    0  10   0
## 4   2.057613 2020   3  28    0  15   0
## 5   2.057613 2020   3  28    0  20   0
## 6   2.572016 2020   3  28    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 0.581 1.173 0.952
2 WRF D-1 -0.059 0.952 0.745
3 WRF D-2 -1.363 2.112 1.789
JFK - WRF 10-m Wind Speed (m/s) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 -1.274 2.226 1.703
2 WRF D-1 -0.224 1.501 1.237
3 WRF D-2 -0.945 2.069 1.527
JFK - WRF 10-m Wind Direction (degN) Performance
Forecast.Init RMSE MAE
1 WRF D-0 34.551 29.002
2 WRF D-1 39.675 34.472
3 WRF D-2 41.770 38.121

Forecast Hour Evaluation for LGA

LGA - WRF 2-m Temperature (K) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 1.467 1.841 1.467
2 WRF D-1 1.142 1.409 1.142
3 WRF D-2 -0.374 1.250 1.111
LGA - WRF 10-m Wind Speed (m/s) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 -6.019 6.197 6.019
2 WRF D-1 -5.477 5.654 5.477
3 WRF D-2 -6.027 6.216 6.027
LGA - WRF 10-m Wind Direction (degN) Performance
Forecast.Init RMSE MAE
1 WRF D-0 15.765 12.865
2 WRF D-1 22.495 19.776
3 WRF D-2 28.852 24.880

Forecast Hour Evaluation for NYC

NYC - WRF 2-m Temperature (K) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 1.467 1.787 1.478
2 WRF D-1 1.095 1.266 1.095
3 WRF D-2 -0.306 1.357 1.254
NYC - WRF 10-m Wind Speed (m/s) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 -4.583 4.747 4.583
2 WRF D-1 -4.355 4.525 4.355
3 WRF D-2 -4.538 4.707 4.538
NYC - WRF 10-m Wind Direction (degN) Performance
Forecast.Init RMSE MAE
1 WRF D-0 12.975 10.171
2 WRF D-1 20.992 15.720
3 WRF D-2 22.947 17.642

uWRF and ASOS Time-Series Visualization

Temperature

Wind Speed

Wind Direction