897
FXXX10 KWNP 291231
DAYTDF

:Product: 3-Day Forecast
:Issued: 2026 Sep 29 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 29-Oct 01 2026 is 2.00 (below NOAA
Scale levels).

NOAA Kp index breakdown Sep 29-Oct 01 2026

             Sep 29       Sep 30       Oct 01
00-03UT       2.00         1.67         1.67
03-06UT       0.33         1.67         1.33
06-09UT       0.67         1.67         1.33
09-12UT       1.33         1.33         1.33
12-15UT       1.00         1.33         1.33
15-18UT       1.33         1.00         1.33
18-21UT       1.33         1.00         1.67
21-00UT       2.00         1.67         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 29-Oct 01 2026

              Sep 29  Sep 30  Oct 01
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 29-Oct 01 2026

              Sep 29        Sep 30        Oct 01
R1-R2           10%           10%           10%
R3 or greater    1%            1%            1%

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