450
FXXX10 KWNP 290031
DAYTDF

:Product: 3-Day Forecast
:Issued: 2025 Aug 29 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 3 (below NOAA
Scale levels).
The greatest expected 3 hr Kp for Aug 29-Aug 31 2025 is 2.67 (below NOAA
Scale levels).

NOAA Kp index breakdown Aug 29-Aug 31 2025

             Aug 29       Aug 30       Aug 31
00-03UT       2.33         1.67         2.67
03-06UT       2.67         1.33         2.00
06-09UT       2.00         1.33         2.33
09-12UT       1.67         1.33         2.33
12-15UT       1.67         1.33         2.33
15-18UT       2.00         1.33         2.33
18-21UT       2.00         1.67         2.33
21-00UT       2.33         1.67         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 Aug 29-Aug 31 2025

              Aug 29  Aug 30  Aug 31
S1 or greater   15%     10%     10%

Rationale: There is a slight chance for an S1 (Minor) or greater solar
radiation storm on 29-31 Aug as the greater than 10 MeV proton flux is
expected to continue a slow, steady declining trend.

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 28 2025 2040 UTC.

Radio Blackout Forecast for Aug 29-Aug 31 2025

              Aug 29        Aug 30        Aug 31
R1-R2           60%           65%           65%
R3 or greater   10%           15%           15%

Rationale: R1/R2 (Minor-Moderate) radio blackouts are likely, with a
slight chance for an isolated R3 (Strong) event, through 30 Aug.