S&P 500 vs. NOAA Kp/Ap Forecasts | October 19–23, 2026

NOAA's latest 3-Day Kp Forecast, updated twice daily, projects a high Monday–Tuesday, low and reversal Wednesday, and recovery into early Friday.

 

 NOAA's latest 45-Day Ap Forecast, updates daily, however, projects a low for Saturday, October 24.

 

Assumptions and methodology:

TPR (2026) - S&P 500 vs. Geomagnetic Ap Index and Kp Index.  

TPR (2026) - S&P 500 vs. Ap Index: +3-Day Lag and Limits of Multi-Week Forecasting.

 

 Result: Week of Oct 19-23, 2026 hourly S&P 500 futures vs. NOAA 3-day Kp, last issued Oct 23, 2026, 8:30 AM ET.

 

Seasonal Cycle for October 2026.