:Product: 3-Day Forecast
:Issued: 2026 Oct 03 0030 UTC
# Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center
#
A. NOAA Geomagnetic Activity Observation and Forecast

The greatest observed 3 hr Kp over the past 24 hours was 1 (below NOAA
Scale levels).
The greatest expected 3 hr Kp for Oct 03-Oct 05 2026 is 4.67 (NOAA Scale
G1).

NOAA Kp index breakdown Oct 03-Oct 05 2026

             Oct 03       Oct 04       Oct 05
00-03UT       1.00         3.67         3.67     
03-06UT       1.33         4.67 (G1)    2.67     
06-09UT       1.33         3.67         3.67     
09-12UT       1.67         2.67         3.00     
12-15UT       2.33         2.67         2.67     
15-18UT       2.00         2.67         3.00     
18-21UT       2.67         3.00         2.33     
21-00UT       3.33         3.67         2.33     

Rationale: G1 (Minor) geomagnetic storms are likely on 04 Oct due to
waning CME effects and a geoeffective +CH/HSS.

B. NOAA Solar Radiation Activity Observation and Forecast

Solar radiation, as observed by NOAA GOES-18 over the past 24 hours, was
below S-scale storm level thresholds.

Solar Radiation Storm Forecast for Oct 03-Oct 05 2026

              Oct 03  Oct 04  Oct 05
S1 or greater    1%      1%      1%

Rationale: No S1 (Minor) or greater solar radiation storms are expected.
No significant active region activity favorable for radiation storm
production is forecast.

C. NOAA Radio Blackout Activity and Forecast

No radio blackouts were observed over the past 24 hours.

Radio Blackout Forecast for Oct 03-Oct 05 2026

              Oct 03        Oct 04        Oct 05
R1-R2            5%            5%            5%
R3 or greater    1%            1%            1%

Rationale: No radio blackouts are expected for 03-05 Oct.