443
FXXX10 KWNP 231231
DAYTDF

:Product: 3-Day Forecast
:Issued: 2025 Aug 23 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 3 (below NOAA
Scale levels).
The greatest expected 3 hr Kp for Aug 23-Aug 25 2025 is 3.67 (below NOAA
Scale levels).

NOAA Kp index breakdown Aug 23-Aug 25 2025

             Aug 23       Aug 24       Aug 25
00-03UT       2.67         1.67         3.00
03-06UT       2.33         1.33         2.00
06-09UT       1.67         1.33         2.00
09-12UT       1.67         1.33         2.67
12-15UT       1.00         1.33         2.67
15-18UT       1.33         1.33         2.67
18-21UT       1.67         1.67         2.67
21-00UT       1.67         1.67         3.67

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 Aug 23-Aug 25 2025

              Aug 23  Aug 24  Aug 25
S1 or greater   25%     10%      5%

Rationale: There is a chance for S1 (Minor) solar radiation storms on 23
Aug, and a slight chance for S1 levels on 24 Aug.

C. NOAA Radio Blackout Activity and Forecast

Radio blackouts reaching the R1 levels were observed over the past 24
hours. The largest was at Aug 22 2025 1859 UTC.

Radio Blackout Forecast for Aug 23-Aug 25 2025

              Aug 23        Aug 24        Aug 25
R1-R2           25%           35%           45%
R3 or greater    1%            5%            5%

Rationale: There is an increasing chance for R1-R2 (Minor-Moderate)
radio blackouts over 23-25 Aug.