752
FXXX10 KWNP 030031
DAYTDF

:Product: 3-Day Forecast
:Issued: 2026 Sep 03 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 2 (below NOAA
Scale levels).
The greatest expected 3 hr Kp for Sep 03-Sep 05 2026 is 1.67 (below NOAA
Scale levels).

NOAA Kp index breakdown Sep 03-Sep 05 2026

             Sep 03       Sep 04       Sep 05
00-03UT       1.67         1.33         1.67
03-06UT       1.67         1.67         1.33
06-09UT       1.33         1.67         1.33
09-12UT       0.33         1.33         1.33
12-15UT       0.67         1.00         1.33
15-18UT       1.33         1.33         1.33
18-21UT       1.33         1.67         1.67
21-00UT       1.33         1.33         1.67

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 Sep 03-Sep 05 2026

              Sep 03  Sep 04  Sep 05
S1 or greater    5%      5%      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

Radio blackouts reaching the R1 levels were observed over the past 24
hours. The largest was at Sep 02 2026 1920 UTC.

Radio Blackout Forecast for Sep 03-Sep 05 2026

              Sep 03        Sep 04        Sep 05
R1-R2           15%           15%           15%
R3 or greater    1%            1%            1%

Rationale: Solar activity will likely reach low levels with isolated to
occasional C-class flare activity, with a slight chance for M-class
flares (R1-R2/Minor-Moderate), through 05 Sep.