361
FXXX10 KWNP 250031
DAYTDF

:Product: 3-Day Forecast
:Issued: 2026 Aug 25 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 25-Aug 27 2026 is 4.00 (below NOAA
Scale levels).

NOAA Kp index breakdown Aug 25-Aug 27 2026

             Aug 25       Aug 26       Aug 27
00-03UT       2.67         1.67         1.67
03-06UT       1.67         1.67         1.33
06-09UT       1.67         1.67         1.33
09-12UT       1.67         1.33         1.67
12-15UT       1.67         0.67         2.33
15-18UT       0.67         1.33         2.67
18-21UT       0.67         1.67         4.00
21-00UT       1.33         1.67         4.00

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 Aug 25-Aug 27 2026

              Aug 25  Aug 26  Aug 27
S1 or greater   30%     10%     10%

Rationale: There is a chance for the greater than 10 MeV proton flux to
reach S1 (Minor) levels on 25 Aug, with a slight chance for S1 levels on
26-27 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 24 2026 1936 UTC.

Radio Blackout Forecast for Aug 25-Aug 27 2026

              Aug 25        Aug 26        Aug 27
R1-R2           45%           45%           45%
R3 or greater   10%           10%           10%

Rationale: There is a chance for R1-R2 (Minor-Moderate) radio blackouts,
and a slight chance for an R3 (Strong) or greater event, over 25-27 Aug.