889
FXXX10 KWNP 100031
DAYTDF

:Product: 3-Day Forecast
:Issued: 2025 Oct 10 0030 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 2 (below NOAA
Scale levels).
The greatest expected 3 hr Kp for Oct 10-Oct 12 2025 is 5.00 (NOAA Scale
G1).

NOAA Kp index breakdown Oct 10-Oct 12 2025

             Oct 10       Oct 11       Oct 12
00-03UT       1.67         2.33         3.00
03-06UT       1.67         2.00         3.00
06-09UT       1.67         2.33         3.67
09-12UT       1.00         2.33         4.67 (G1)
12-15UT       1.33         3.00         3.00
15-18UT       1.33         3.33         3.67
18-21UT       1.33         3.67         5.00 (G1)
21-00UT       1.67         4.00         3.67

Rationale: G1 (Minor) geomagnetic storms are likely on 12 Oct due to the
anticipated influence of a negative polarity CH HSS influences.

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 10-Oct 12 2025

              Oct 10  Oct 11  Oct 12
S1 or greater    5%      5%      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

Radio blackouts reaching the R1 levels were observed over the past 24
hours. The largest was at Oct 09 2025 1231 UTC.

Radio Blackout Forecast for Oct 10-Oct 12 2025

              Oct 10        Oct 11        Oct 12
R1-R2           25%           25%           25%
R3 or greater    5%            5%            5%

Rationale: There is a chance for R1-R2 (Minor-Moderate) radio blackouts
over 10-12 Oct.