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 2020-04-13 00:00:05 2020   4  13    0   0  5.0004    283.8241      0.00624
## 2 2020-04-13 00:00:10 2020   4  13    0   0 10.0008    283.9417      0.00625
## 3 2020-04-13 00:00:15 2020   4  13    0   0 15.0012    284.0410      0.00625
## 4 2020-04-13 00:00:20 2020   4  13    0   0 20.0016    284.1282      0.00625
## 5 2020-04-13 00:00:24 2020   4  13    0   0 24.9984    284.2056      0.00625
## 6 2020-04-13 00:00:29 2020   4  13    0   0 29.9988    284.2758      0.00626
##     U_WIND  V_WIND Wind.Speed Wind.Direction Station
## 1 -0.36565 5.22576   5.238537       175.9975     JFK
## 2 -0.41412 4.97756   4.994757       175.2441     JFK
## 3 -0.44710 4.79333   4.814137       174.6711     JFK
## 4 -0.46841 4.63671   4.660310       174.2314     JFK
## 5 -0.48690 4.51559   4.541764       173.8458     JFK
## 6 -0.48808 4.41032   4.437245       173.6849     JFK
##             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
##   Station           Date.Time Temperature Relative.Humidity Wind.Direction
## 1     JFK 2020-04-12 00:00:00         NaN               NaN            280
## 2     JFK 2020-04-12 00:05:00         NaN               NaN            270
## 3     JFK 2020-04-12 00:10:00         NaN               NaN            280
## 4     JFK 2020-04-12 00:15:00         NaN               NaN            280
## 5     JFK 2020-04-12 00:20:00         NaN               NaN            270
## 6     JFK 2020-04-12 00:25:00         NaN               NaN            280
##   Wind.Speed year mon day hour min sec
## 1   4.115226 2020   4  12    0   0   0
## 2   5.658436 2020   4  12    0   5   0
## 3   5.144033 2020   4  12    0  10   0
## 4   5.658436 2020   4  12    0  15   0
## 5   4.629630 2020   4  12    0  20   0
## 6   5.144033 2020   4  12    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 0.390 1.068 0.888
2 WRF D-1 -0.062 0.659 0.486
3 WRF D-2 -0.076 0.968 0.639
JFK - WRF 10-m Wind Speed (m/s) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 -3.091 3.817 3.200
2 WRF D-1 -2.022 3.248 2.627
3 WRF D-2 -2.598 3.509 2.941
JFK - WRF 10-m Wind Direction (degN) Performance
Forecast.Init RMSE MAE
1 WRF D-0 11.037 8.261
2 WRF D-1 12.709 9.726
3 WRF D-2 28.090 14.150

Forecast Hour Evaluation for LGA

LGA - WRF 2-m Temperature (K) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 -0.092 1.220 0.904
2 WRF D-1 -0.290 1.170 0.974
3 WRF D-2 -0.238 1.437 1.128
LGA - WRF 10-m Wind Speed (m/s) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 -4.306 4.962 4.311
2 WRF D-1 -3.857 4.968 3.893
3 WRF D-2 -4.303 4.969 4.354
LGA - WRF 10-m Wind Direction (degN) Performance
Forecast.Init RMSE MAE
1 WRF D-0 14.866 10.686
2 WRF D-1 14.791 9.889
3 WRF D-2 33.787 17.190

Forecast Hour Evaluation for NYC

NYC - WRF 2-m Temperature (K) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 1.082 1.656 1.168
2 WRF D-1 1.115 1.613 1.356
3 WRF D-2 1.482 2.167 1.783
NYC - WRF 10-m Wind Speed (m/s) Performance
Forecast.Init BIAS RMSE MAE
1 WRF D-0 -2.268 2.593 2.279
2 WRF D-1 -2.282 2.604 2.282
3 WRF D-2 -2.376 2.643 2.388
NYC - WRF 10-m Wind Direction (degN) Performance
Forecast.Init RMSE MAE
1 WRF D-0 26.881 18.154
2 WRF D-1 31.695 19.971
3 WRF D-2 29.475 20.516

uWRF and ASOS Time-Series Visualization

Temperature

## Warning: Removed 55 rows containing missing values (geom_point).
## Warning: Removed 38 rows containing missing values (geom_path).

Wind Speed

## Warning: Removed 24 rows containing missing values (geom_point).

Wind Direction