300
FXXX10 KWNP 011231
DAYTDF

:Product: 3-Day Forecast
:Issued: 2026 Sep 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 2 (below NOAA
Scale levels).
The greatest expected 3 hr Kp for Sep 01-Sep 03 2026 is 2.00 (below NOAA
Scale levels).

NOAA Kp index breakdown Sep 01-Sep 03 2026

             Sep 01       Sep 02       Sep 03
00-03UT       1.00         2.00         1.67
03-06UT       1.33         1.67         1.67
06-09UT       2.00         1.67         1.33
09-12UT       1.33         1.33         0.67
12-15UT       1.33         0.67         0.67
15-18UT       1.67         1.33         1.33
18-21UT       2.00         1.33         1.33
21-00UT       2.00         1.67         1.33

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 Sep 01-Sep 03 2026

              Sep 01  Sep 02  Sep 03
S1 or greater    1%      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 Sep 01-Sep 03 2026

              Sep 01        Sep 02        Sep 03
R1-R2           10%           10%           10%
R3 or greater    1%            1%            1%

Rationale: There is a slight chance for R1-R2 (Minor-Moderate) radio
blackouts on 01-03 Sep.