855
FXXX10 KWNP 011231
DAYTDF

:Product: 3-Day Forecast
:Issued: 2025 Dec 01 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 Dec 01-Dec 03 2025 is 4.00 (below NOAA
Scale levels).

NOAA Kp index breakdown Dec 01-Dec 03 2025

             Dec 01       Dec 02       Dec 03
00-03UT       4.00         1.33         3.00
03-06UT       1.00         1.33         3.67
06-09UT       1.67         1.67         3.00
09-12UT       2.00         1.33         3.00
12-15UT       1.67         1.33         2.00
15-18UT       0.67         1.33         2.67
18-21UT       0.67         1.67         3.00
21-00UT       1.67         1.67         3.00

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 01-Dec 03 2025

              Dec 01  Dec 02  Dec 03
S1 or greater   20%     20%     20%

Rationale: There is a slight chance for the greater than 10 MeV proton
flux to reach S1 (Minor) levels through 03 Dec, due primarily to the
eruptive potential of Region2 4294 and 4299.

C. NOAA Radio Blackout Activity and Forecast

Radio blackouts reaching the R3 levels were observed over the past 24
hours. The largest was at Dec 01 2025 0249 UTC.

Radio Blackout Forecast for Dec 01-Dec 03 2025

              Dec 01        Dec 02        Dec 03
R1-R2           70%           70%           70%
R3 or greater   20%           20%           20%

Rationale: R1-R2 (Minor-Moderate) radio blackouts are likely, with a
slight chance for an R3 (Strong) or greater event, on 01-03 Dec.