386
FXXX10 KWNP 081231
DAYTDF

:Product: 3-Day Forecast
:Issued: 2025 Oct 08 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 08-Oct 10 2025 is 4.67 (NOAA Scale
G1).

NOAA Kp index breakdown Oct 08-Oct 10 2025

             Oct 08       Oct 09       Oct 10
00-03UT       3.00         3.00         1.67
03-06UT       3.67         2.67         1.67
06-09UT       3.00         2.00         1.67
09-12UT       2.33         1.67         1.33
12-15UT       2.00         1.33         1.33
15-18UT       2.00         1.33         1.33
18-21UT       2.67         1.67         1.33
21-00UT       4.67 (G1)    1.67         1.33

Rationale: G1 (Minor) geomagnetic storming is likely on 08 Oct due to
influences from 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 08-Oct 10 2025

              Oct 08  Oct 09  Oct 10
S1 or greater    5%      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 08-Oct 10 2025

              Oct 08        Oct 09        Oct 10
R1-R2           35%           30%           30%
R3 or greater   10%            5%            5%

Rationale: A chance for R1-R2 (Minor-Moderate) radio blackouts due to
M-class flare activity, with a slight chance for an isolated R3 (Strong)
event, will persist through 08 Oct. Probabilities undergo a minor
decrease on 09-10 Oct as Region 4236 exits the western limb.