006
FXXX10 KWNP 301231
DAYTDF

:Product: 3-Day Forecast
:Issued: 2025 Sep 30 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 7 (NOAA Scale
G3).
The greatest expected 3 hr Kp for Sep 30-Oct 02 2025 is 7.33 (NOAA Scale
G3).

NOAA Kp index breakdown Sep 30-Oct 02 2025

             Sep 30       Oct 01       Oct 02
00-03UT       5.33 (G1)    4.00         2.33
03-06UT       7.33 (G3)    3.67         2.00
06-09UT       6.00 (G2)    3.33         1.67
09-12UT       5.33 (G1)    3.00         1.67
12-15UT       5.00 (G1)    2.67         1.33
15-18UT       4.67 (G1)    2.67         1.33
18-21UT       5.00 (G1)    2.67         1.67
21-00UT       4.00         2.67         1.67

Rationale: G1 (Minor) geomagnetic storms are expected 30 Sep due to a
CME/MC influence.

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 30-Oct 02 2025

              Sep 30  Oct 01  Oct 02
S1 or greater    5%      5%      5%

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 30 2025 0940 UTC.

Radio Blackout Forecast for Sep 30-Oct 02 2025

              Sep 30        Oct 01        Oct 02
R1-R2           60%           60%           60%
R3 or greater   15%           15%           15%

Rationale: R1-R2 (Minor-Moderate) radio blackouts are likely with a
slight chance for R3 (strong) event through 02 Oct.