# A Microscopic Traffic Flow Model Characterization for Weather Conditions
## 5 Performance Evaluation
It then increases to 0.04 at 109.9 m, decreases to 0.03 at 166.5 m, and decreases further at 512.8 m, as shown in Figure 8b. The density between 0 s and 34.5 s is 0.14, which indicates a traffic queue. The queue then gradually dissipates, and at 118 s, the density decreases to 0.04 at 96.57 m, as shown in Figure 8b. With \(\delta\) = 20, the density between \(-\)63.27 m and \(-\)36.63 m at 117.5 s is 0.14, which indicates a traffic queue. The density then decreases to 0.01 at 126.5 m, as shown in Figure 8c. The density between 0 s and 35.0 s is 0.14, which indicates a traffic queue. The density at 62.0 s gradually decreases to 0.06 at \(-\)69.9 s. The queue develops again at 74.0 s and \(-\)39.96 m, with a density of 0.14, and at 120 s is between \(-\)63.27 m and \(-\)36.63 m, as shown in Figure 8c. Figure 8a-c show that as \(\delta\) increases the changes in density over time increase, which indicates that the model is not stable. Figure 7: Traffic flow evolution over time with the proposed model over an 800 m circular road. Figure 8: _Cont_. Figure 8: _Cont._  
0.05 at 63.27 m and decreases to 0.01 at 299.7 m, where it remains, as shown in Figure 8f. The density between 0 s and 34.5 s is 0.14, which indicates a traffic queue. After the queue dissipates, the density at 55.5 s decreases to 0.06 at \(-\)73.26 m and then to 0.05 at 119.5 s at 63.27 m, as shown in Figure 8f. With \(\alpha~{}=~{}0.7\), the density between 0 m and 3.33 m at 119.5 s is 0.01. It then increases to 0.04 at 113.2 and decreases to 0.01 at 299.7 m, where it remains, as shown in Figure 8g. The density between 0 s and 34.5 s is 0.14, which indicates a queue. After the queue dissipates, the density at 49.0 s gradually decreases to 0.06 at \(-\)79.92 m. It then decreases to 0.03 at 119.5 s and 113.2 m, as shown in Figure 8g. With \(\alpha~{}=~{}0.8\), the density between 0 m and 63.27 m at 118.5 s is 0.01. It then increases to 0.03 at 149.9 m and decreases to 0.01 at 366.6 m, as shown in Figure 8h. The density between 0 s and 34.5 s is 0.14, which indicates a queue. After the queue dissipates, the density decreases to 0.06 at 48.5 s and \(-\)83.24 m and then to 0.03 at 119 s and 149.9 m, as shown in Figure 8h. With \(\alpha~{}=~{}0.9\), the density between 0 m and 86.58 m at 118.5 s is 0.01. It increases to 0.033 at 203.3 m and decreases to 0.015 at 496.2 m, as shown in Figure 8i. The density between 0 s and 35.5 s is 0.14, which indicates a queue. After the queue dissipates, the density decreases to 0.05 at 52.0 s and \(-\)69.93 m and then to 0.033 at 119.5 s and 203.3 m, as shown in Figure 8i. Figure 8d-i show that as the weather severity index \(\alpha\) increases, the changes in density with the proposed model decrease over time, which is realistic. The density of the proposed model for a platoon of 30 vehicles with \(\alpha~{}=~{}0\) and \(\alpha~{}=~{}0.9\) is presented in Figure 8j,k, respectively. With \(\alpha~{}=~{}0\), the density between \(-\)99.90 m and \(-\)96.57 m at 150 s is 0.5, which indicates a traffic queue. After the queue dissipates, the density decreases to 0.02 at 73.26 m and remains there until 662.7 m. It then increases to 0.064 at 696.0 m, as shown in Figure 8j. The density between 0 s and 49.0 s at \(-\)53.28 m is 0.5, which indicates a traffic queue. The density at 55.0 s gradually decreases to 0.31 at \(-\)49.95 m. The queue again develops at 57.5 s and \(-\)56.67 m, with a density of 0.5, and remains there until 150 s, as shown in Figure 8j. With \(\alpha~{}=~{}0.9\), the density between \(-\)109.9 m and \(-\)66.6 m at 146.5 s is 0.02. It increases to 0.09 at 6.66 m and decreases to 0.037 at 133.2 m, where it remains, as shown in Figure 8k. The density between 0 s and 44.5 s is 0.5, which indicates a traffic queue. After the queue dissipates, the density decreases to 0.21 at 62.5 s and \(-\)49.95 m and then decreases to 0.09 at 148.5 s and 6.66 m, as shown in Figure 8k. The above results show that the changes in velocity and density with the proposed model decrease as the weather becomes more adverse.