:Product: 3-Day Forecast
:Issued: 2025 Dec 14 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 5 (NOAA Scale
G1).
The greatest expected 3 hr Kp for Dec 14-Dec 16 2025 is 3.67 (below NOAA
Scale levels).

NOAA Kp index breakdown Dec 14-Dec 16 2025

             Dec 14       Dec 15       Dec 16
00-03UT       2.67         2.67         2.67     
03-06UT       3.67         2.67         2.67     
06-09UT       3.00         3.00         2.00     
09-12UT       2.67         2.67         1.67     
12-15UT       2.67         1.67         1.67     
15-18UT       2.00         1.67         0.67     
18-21UT       1.67         2.00         1.67     
21-00UT       2.67         2.67         2.67     

Rationale: No G1 (Minor) or greater geomagnetic storms are expected.  No
significant transient or recurrent solar wind features are forecast.

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 Dec 14-Dec 16 2025

              Dec 14  Dec 15  Dec 16
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 Dec 14-Dec 16 2025

              Dec 14        Dec 15        Dec 16
R1-R2           30%           25%           25%
R3 or greater    1%            1%            1%

Rationale: There is a chance for R1-R2 (Minor-Moderate) radio blackouts
over 14-16 Dec.