Marchuk: Efficient Global Weather Forecasting from Mid-Range to Sub-Seasonal Scales via Flow Matching
This work addresses the sharp performance degradation of conventional models in subseasonal (up to 30-day) global weather forecasting, a challenge rooted in atmospheric chaos. To overcome this limitation, the authors propose Marchuk, a generative latent-space autoregressive model based on flow matching. By replacing Rotary Position Embedding (RoPE) with trainable positional embeddings and extending the temporal context window, Marchuk substantially enhances its capacity to model long-range temporal dependencies. Remarkably, with only 276 million parameters—far fewer than the 1.6 billion in comparable models—it achieves forecasting accuracy on par with LaDCast over the full 30-day horizon while offering significantly faster inference. The code and model weights have been publicly released.