Hybrid Deep Learning and Bayesian Framework for Long-Term Fog Forecasting: A Case Study at Lucknow Airport in the Indo-Gangetic Plains

Authors

  • Deep Chaulya

    Department of Computer Science and Engineering, Indian Institute of Technology Patna, Patna 801106, India

DOI:

https://doi.org/10.30564/jasr.v9i2.13144
Received: 9 February 2026 | Revised: 9 March 2026 | Accepted: 23 April 2026 | Published Online: 28 April 2026

Abstract

Fog significantly affects aviation, transportation, agriculture, and energy in North India during winter. Accurate prediction is difficult due to nonlinear meteorological interactions and uncertainty. Traditional models provide point estimates without uncertainty, while Bayesian methods offer probabilistic outputs but struggle to capture complex temporal dependencies in atmospheric time-series data effectively. To address these limitations, this study proposes a hybrid long-term forecasting framework that integrates a three-layer Bidirectional Long Short-Term Memory (BiLSTM) network with a Modified Bayesian Beta Regression model. The model is trained and evaluated using 24 years (2000–2023) of meteorological observations from Lucknow Airport, representing a fog-prone region within the Indo-Gangetic Plains. Fog behaviour was represented through a normalized Fog Index (0–1) that incorporates both intensity and persistence, offering a more stable and informative forecast target than raw visibility. The BiLSTM component captures temporal dependencies and produces accurate point forecasts, achieving a root mean square error (RMSE) of 0.125 for a three-day prediction horizon. The Bayesian layer enhances reliability by generating calibrated uncertainty intervals. The resulting model achieved an average interval width of approximately 0.59 and a prediction interval coverage close to 80%, effectively representing both aleatoric and epistemic uncertainty. Additional techniques, including Min-Max normalization, sequence windowing, Fast Fourier Transform (FFT) feature augmentation, learning-rate scheduling, and Monte Carlo dropout, improved generalization and model stability. The proposed hybrid framework outperforms standalone models and shows strong potential for operational fog forecasting, offering both accurate predictions and uncertainty-aware confidence estimates for aviation, transportation, and early-warning systems.

Keywords:

Fog Index Forecasting; BiLSTM; Deep Learning; Modified Bayesian Regression; Time-Series Analysis

References

[1] Ghude, S.D., Jenamani, R.K., Kulkarni, R., et al., 2023. WiFEX: Walk into the warm fog over Indo-Gangetic Plain Region. Bulletin of the American Meteorological Society. 104, E980–E1005. DOI: https://doi.org/10.1175/BAMS-D-21-0197.1

[2] Gultepe, I., Tardif, R., Michaelides, S.C., et al., 2007. Fog research: A review of past achievements and future perspectives. Pure and Applied Geophysics. 164, 1121–1159. DOI: https://doi.org/10.1007/s00024-007-0211-x

[3] Ghude, S.D., Bhat, G.S., Prabhakaran, T., et al., 2017. Winter fog experiment over the Indo-Gangetic plains of India. Current Science. 112, 767–784. DOI: https://doi.org/10.18520/cs/v112/i04/767-784

[4] Bharali, C., Barth, M., Kumar, R., et al., 2024. Role of atmospheric aerosols in severe winter fog over the Indo-Gangetic Plain of India: A case study. Atmospheric Chemistry and Physics. 24, 6635–6662. DOI: https://doi.org/10.5194/acp-24-6635-2024

[5] Saraf, A.K., Bora, A.K., Das, J., et al., 2011. Winter fog over the Indo-Gangetic Plains: Mapping and modelling using remote sensing and GIS. Natural Hazards. 58, 199–220. DOI: https://doi.org/10.1007/s11069-010-9660-0

[6] Peláez-Rodríguez, C., Pérez-Aracil, J., de López-Diz, A., et al., 2023. Deep learning ensembles for accurate fog-related low-visibility events forecasting. Neurocomputing. 549, 126435. DOI: https://doi.org/10.1016/j.neucom.2023.126435

[7] Dutta, D., Chaudhuri, S., 2015. Nowcasting visibility during wintertime fog over the airport of a metropolis of India: Decision tree algorithm and artificial neural network approach. Natural Hazards. 75, 1349–1368. DOI: https://doi.org/10.1007/s11069-014-1388-9

[8] Dhangar, N., Nparde, A., Ahmed, R., et al., 2022. Fog nowcasting over the IGI airport, New Delhi, India using decision tree. MAUSAM. 73, 785–794. DOI: https://doi.org/10.54302/mausam.v73i4.3441

[9] Sharma, S., Bajaj, K., Deshpande, K., et al., 2024. Short-term Fog Forecasting Using Meteorological Observations at Airports in North India. In Proceedings of the 7th Joint International Conference on Data Science & Management of Data (11th ACM IKDD CODS and 29th COMAD), Bangalore, India, 4–7 January 2024. DOI: https://doi.org/10.1145/3632410.3632449

[10] van der Velde, I.R., Steeneveld, G.J., Schreur, B.G.J.W., et al., 2010. Modeling and forecasting the onset and duration of severe radiation fog under frost conditions. Monthly Weather Review. 138, 4237–4253. DOI: https://doi.org/10.1175/2010MWR3427.1

[11] Goswami, P., Sarkar, S., 2017. An analogue dynamical model for forecasting fog-induced visibility: Validation over Delhi. Meteorological Applications. 24, 360–375. DOI: https://doi.org/10.1002/met.1634

[12] Hochreiter, S., Schmidhuber, J., 1997. Long short-term memory. Neural Computation. 9, 1735–1780.

[13] Zhou, B., Du, J., 2010. Fog prediction from a multi-model mesoscale ensemble prediction system. Weather and Forecasting. 25, 303–322. DOI: https://doi.org/10.1175/2009WAF2222289.1

[14] Bendix, J., 2002. A satellite-based climatology of fog and low-level stratus in Germany and adjacent areas. Atmospheric Research. 64, 3–18. DOI: https://doi.org/10.1016/S0169-8095(02)00075-3

[15] Ahn, M., Sohn, E., Hwang, B., 2003. A new algorithm for sea fog/stratus detection using GMS-5 IR data. Advances in Atmospheric Sciences. 20, 899–913. DOI: https://doi.org/10.1007/BF02915513

[16] Bendix, J., Cermak, J., Thies, B., 2004. New Perspectives in Remote Sensing of Fog and Low Stratus—TERRA/AQUA-MODIS and MSG. In Proceedings of the 3rd International Conference on Fog, Fog Collection and Dew, Cape Town, South Africa, 11–15 October 2004; pp. G2.1–G2.4.

[17] Bendix, J., Thies, B., Cermak, J., et al., 2005. Ground fog detection from space based on MODIS daytime data—A feasibility study. Weather and Forecasting. 20, 989–1005. DOI: https://doi.org/10.1175/WAF886.1

[18] Ellrod, G.P., Lindstrom, S., 2006. Performance of satellite fog detection techniques associated with major fog-related highway accidents. Environmental Science and Engineering. Available from: https://www.semanticscholar.org/paper/Performance-of-Satellite-Fog-Detection-Techniques-Ellrod-Lindstrom/af145aee2c5f94a24b56ecb0f42c3fb8734193d6

[19] Yoo, J., Jeong, M., Yoo, H., et al., 2006. Fog sensing over the Korean Peninsula derived from satellite observation of MODIS and GEOS-9. Korean Journal of Remote Sensing. 22, 373–377.

[20] Choudhury, S., Rajpal, H., Saraf, A.K., et al., 2007. Technical Note: Mapping and forecasting of North Indian winter fog: An application of spatial technologies. International Journal of Remote Sensing. 28, 3649–3663.

[21] Ward, B., Croft, P.J., 2008. Use of GIS to examine winter fog occurrences. Electronic Journal of Operational Meteorology. 33. Available from: https://www.semanticscholar.org/paper/Use-of-GIS-to-Examine-Winter-Fog-Occurrences-Ward-Croft/6ce9e6015978c5b31aa77c56b90b6b1f843ec60f

[22] Zhang, J., Lu, H., Xia, Y., et al., 2018. Deep Convolutional neural network for fog detection. In Intelligent Computing Theories and Application. Springer: Cham, Switzerland. DOI: https://doi.org/10.1007/978-3-319-95933-7_1

[23] Kopecká, J., Kopecký, D., Štursa, D., et al., 2026. Estimation of atmospheric visibility by deep learning model using multimodal dataset. Knowledge-Based Systems. 331, 114732. DOI: https://doi.org/10.1016/j.knosys.2025.114732

[24] Castillo-Botón, C., Casillas-Pérez, D., Casanova-Mateo, C., et al., 2022. Machine learning regression and classification methods for fog events prediction. Atmospheric Research. 272, 106157. DOI: https://doi.org/10.1016/j.atmosres.2022.106157

[25] Shi, X., Chen, Z., Wang, H., et al., 2015. Convolutional LSTM Network: A Machine Learning Approach for Precipitation Nowcasting. arXiv preprint. arXiv:1506.04214.

[26] Wagenbrenner, N.S., Forthofer, J.M., Page, W.G., et al., 2019. Development and Evaluation of a Reynolds-Averaged Navier–Stokes Solver in WindNinja for Operational Wildland Fire Applications. Atmosphere. 10, 672. DOI: https://doi.org/10.3390/atmos10110672

[27] Xiang, Y., Zhang, Q., Wang, M., et al., 2025. A hybrid forecasting approach for sea fog based on machine learning. Artificial Intelligence for the Earth Systems. 5, e250013. DOI: https://doi.org/10.1175/AIES-D-25-0013.1

[28] Pagowski, M., Gultepe, I., King, P., 2004. Analysis and modeling of an extremely dense fog event in southern Ontario. Journal of Applied Meteorology and Climatology. 43, 3–16. DOI: https://doi.org/10.1175/1520-0450(2004)043<0003:AAMOAE>2.0.CO;2

[29] Hinton, G.E., Salakhutdinov, R.R., 2006. Reducing the dimensionality of data with neural networks. Science. 313, 504–507. DOI: https://doi.org/10.1126/science.1127647

[30] Palvanov, A., Cho, Y.I., 2019. VisNet: Deep convolutional neural networks for forecasting atmospheric visibility. Sensors. 19, 1343. DOI: https://doi.org/10.3390/s19061343

[31] Vaswani, A., Shazeer, N., Parmar, N., et al., 2017. Attention is All You Need. arXiv preprint. arXiv:1706.03762.

[32] Steeneveld, G.J., Ronda, R.J., Holtslag, A.A.M., 2015. The challenge of forecasting the onset and development of radiation fog using mesoscale atmospheric models. Boundary-Layer Meteorology. 154, 265–289. DOI: https://doi.org/10.1007/s10546-014-9973-8

[33] Ranjan, P., Akshay, V., Kumar, P.R.G., et al., 2025. Improving weather predictions accuracy with a hybrid LSTM-Transformer model: A study on Indian climate. IEEE Access. 13, 169014–169025. DOI: https://doi.org/10.1109/ACCESS.2025.3614473

[34] Miao, K.C., Han, T.T., Yao, Y.Q., et al., 2020. Application of LSTM for short term fog forecasting based on meteorological elements. Neurocomputing. 408, 285–291.

[35] Lu, Z., Zheng, C., Yang, T., 2020. Application of offshore visibility forecast based on temporal convolutional network and transfer learning. Computational Intelligence and Neuroscience. 8882279. DOI: https://doi.org/10.1155/2020/8882279

[36] Kamangir, H., Collins, W., Tissot, P., et al., 2021. FogNet: A multiscale 3D CNN with double-branch dense block and attention mechanism for fog prediction. Machine Learning with Applications. 5, 100038. DOI: https://doi.org/10.1016/j.mlwa.2021.100038

[37] Chen, K., Zhou, Y., Ren, T., et al., 2024. Short-term sea fog area forecast: A new data set and deep-learning pixel-level model. Journal of Geophysical Research. DOI: https://doi.org/10.1029/2024JH000230

[38] Qu, Y., Fang, Y., Ji, S., et al., 2024. Deep learning-based atmospheric visibility detection. Atmosphere. 15, 1394. DOI: https://doi.org/10.3390/atmos15111394

[39] Peláez-Rodríguez, C., Pérez-Aracil, J., Casanova-Mateo, C., et al., 2023. Efficient prediction of fog-related low-visibility events with Machine Learning and evolutionary algorithms. Atmospheric Research. 295, 106991. DOI: https://doi.org/10.1016/j.atmosres.2023.106991

[40] Salcedo-Sanz, S., Guijo-Rubio, D., Pérez-Aracil, J., et al., 2025. Artificial intelligence-based methods and algorithms in fog and atmospheric low-visibility forecasting. Atmosphere. 16, 1073. DOI: https://doi.org/10.3390/atmos16091073

[41] Smith, D.K.E., Reka, S., Dorling, S.R., et al., 2024. Forecasts of fog events in northern India dramatically improve when weather prediction models include irrigation effects. Communications Earth & Environment. 5, 141. DOI: https://doi.org/10.1038/s43247-024-01314-w

[42] Shankar, A., Kumar, A., Sinha, V., 2024. Machine learning approach in the prediction of fog: An early warning system. MAUSAM. 75, 1039–1050. DOI: https://doi.org/10.54302/mausam.v75i4.5919

[43] Ortega, L.C., Otero, L.D., Solomon, M., et al., 2023. Deep learning models for visibility forecasting using climatological data. International Journal of Forecasting. 39, 992–1004.

[44] Singh, A., Maheskumar, R.S., Iyengar, G.R., 2022. A diagnostic method for fog forecasting using numerical weather prediction (NWP) model outputs. Journal of Atmospheric Science Research. 5(4), 10–19. DOI: https://doi.org/10.30564/jasr.v5i4.5068

[45] Bartok, J., Bott, A., Gera, M., 2012. Fog prediction for road traffic safety in a coastal desert region. Boundary-Layer Meteorology. 145, 485–506. DOI: https://doi.org/10.1007/s10546-012-9750-5

[46] Safai, P.D., Ghude, S., Pithani, P., et al., 2019. Two-way relationship between aerosols and fog: A case study at IGI Airport, New Delhi. Aerosol and Air Quality Research. 19(1), 71–79. DOI: https://doi.org/10.4209/aaqr.2017.11.0542

[47] Arun, S.H., Singh, C., John, S., et al., 2022. A study to improve the fog/visibility forecast at IGI Airport, New Delhi during the winter season 2020–2021. Journal of Earth System Science. 131, 124. DOI: https://doi.org/10.1007/s12040-022-01874-5

[48] Goswami, S., Chaudhuri, S., Das, D., et al., 2020. Adaptive neuro-fuzzy inference system to estimate the predictability of visibility during fog over Delhi, India. Meteorological Applications. 27, e1900. DOI: https://doi.org/10.1002/met.1900

[49] Gal, Y., Ghahramani, Z., 2015. Dropout as a Bayesian approximation: Representing model uncertainty in deep learning. arXiv preprint. arXiv:1506.02142.

[50] MacKay, D.J., 1992. A practical Bayesian framework for backpropagation networks. Neural Computation. 4, 448–472.

[51] Neal, R.M., 2012. Bayesian Learning for Neural Networks. Springer: New York, NY, USA.

[52] Blundell, C., Julien, C., Koray, K., et al., 2015. Weight uncertainty in neural network. arXiv preprint. arXiv:1505.05424.

[53] Rasmussen, C.E., Williams, C.K.I., 2006. Gaussian Processes for Machine Learning. MIT Press: Cambridge, MA, USA.

[54] Gneiting, T., Katzfuss, M., 2014. Probabilistic forecasting. Annual Review of Statistics and Its Application. 1, 125–151. DOI: https://doi.org/10.1146/annurev-statistics-062713-085831

[55] Raftery, A.E., Gneiting, T., Balabdaoui, F., et al., 2005. Using Bayesian model averaging to calibrate forecast ensembles. Monthly Weather Review. 133, 1155–1174. DOI: https://doi.org/10.1175/MWR2906.1

[56] Bishop, C.M., Nasrabadi, N.M., 2006. Pattern Recognition and Machine Learning. Springer: New York, NY, USA.

[57] Pinson, P., 2013. Wind energy: Forecasting challenges for its operational management. Statistical Science. 28, 564–585. DOI: https://doi.org/10.1214/13-STS445

[58] Boukabara, S.A., Krasnopolsky, V., Penny, S.G., et al., 2021. Outlook for exploiting artificial intelligence in the earth and environmental sciences. Bulletin of the American Meteorological Society. 102, E1016–E1032. DOI: https://doi.org/10.1175/BAMS-D-20-0031.1

[59] Ait Ouadil, K., Idbraim, S., Bouhsine, T., et al., 2024. Atmospheric visibility estimation: A review of deep learning approach. Multimedia Tools and Applications. 83, 36261–36286. DOI: https://doi.org/10.1007/s11042-023-16855-z

[60] Kuleshov, V., Fenner, N., Ermon, S., 2018. Accurate uncertainties for deep learning using calibrated regression. arXiv preprint. arXiv:1807.00263.

[61] Rahaman, R., Theiry, A.H., 2020. Uncertainty quantification and deep ensembles. arXiv preprint. arXiv:2007.08792. DOI: https://doi.org/10.48550/arXiv.2007.08792

[62] Bajaj, K., Mannam, U., Deshpande, P., et al., 2024. Forecasting of fog index and prediction interval using Bayesian methods. In Proceedings of the 8th International Conference on Data Science and Management of Data (12th ACM IKDD CODS and 30th COMAD), Jodhpur, India, 18–21 December 2024; pp. 270–278. DOI: https://doi.org/10.1145/3703323.3703738

Downloads

How to Cite

Chaulya, D. (2026). Hybrid Deep Learning and Bayesian Framework for Long-Term Fog Forecasting: A Case Study at Lucknow Airport in the Indo-Gangetic Plains. Journal of Atmospheric Science Research, 9(2), 26–63. https://doi.org/10.30564/jasr.v9i2.13144