261
FXXX10 KWNP 051231
DAYTDF

:Product: 3-Day Forecast
:Issued: 2025 Oct 05 1230 UTC
# Prepared by the US Dept. of Commerce, NOAA, Space Weather Prediction Center
# Product description and SWPC contact on the Web
# http://www.swpc.noaa.gov/wwire.html
#
#             3-Day Forecast
#
A. NOAA Geomagnetic Activity Observation and Forecast

The greatest observed 3 hr Kp over the past 24 hours was 4 (below NOAA
Scale levels).
The greatest expected 3 hr Kp for Oct 05-Oct 07 2025 is 4.67 (NOAA Scale
G1).

NOAA Kp index breakdown Oct 05-Oct 07 2025

             Oct 05       Oct 06       Oct 07
00-03UT       2.67         3.33         2.00
03-06UT       3.33         3.67         2.67
06-09UT       2.67         3.33         3.00
09-12UT       2.00         3.00         2.33
12-15UT       3.00         2.33         4.33
15-18UT       3.00         2.00         3.00
18-21UT       3.33         3.00         4.67 (G1)
21-00UT       3.00         3.33         3.00

Rationale: Periods of G1 (Minor) geomagnetic storms are likely on 07 Oct
due to CH HSS influences and the anticipated arrival of two slow-moving
CMEs that left the Sun on 03 Oct.

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 05-Oct 07 2025

              Oct 05  Oct 06  Oct 07
S1 or greater   10%     10%     10%

Rationale: There is a slight chance for S1 (Minor) solar radiation
storms over 05-07 Oct.

C. NOAA Radio Blackout Activity and Forecast

No radio blackouts were observed over the past 24 hours.

Radio Blackout Forecast for Oct 05-Oct 07 2025

              Oct 05        Oct 06        Oct 07
R1-R2           60%           60%           60%
R3 or greater   15%           15%           15%

Rationale: R1-R2 (Minor-Moderate) radio blackouts are likely, with a
slight chance for an R3 (Strong) or greater event, over 05-07 Oct.