Currently, there are no forecasts of Kp from the Sheffield NARMAX model.
Key model publications
Jose Roberto Ayala Solares, Hua-Liang Wei, R. J. Boynton, Simon N. Walker, and Stephen A. Billings
Modelling and Prediction of Global Magnetic Disturbance in Near-Earth Space: a Case Study for Kp Index Using NARX Models
Space Weather 14, 899-916, doi:10.1002/2016SW001463, 2016.