301
FXXX10 KWNP 170031
DAYTDF

:Product: 3-Day Forecast
:Issued: 2025 Nov 17 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 4 (below NOAA
Scale levels).
The greatest expected 3 hr Kp for Nov 17-Nov 19 2025 is 4.67 (NOAA Scale
G1).

NOAA Kp index breakdown Nov 17-Nov 19 2025

             Nov 17       Nov 18       Nov 19
00-03UT       3.67         3.00         2.67
03-06UT       4.67 (G1)    3.67         2.00
06-09UT       4.00         3.00         2.33
09-12UT       3.67         2.67         2.33
12-15UT       3.33         2.33         2.33
15-18UT       3.33         2.33         2.33
18-21UT       3.00         2.33         2.33
21-00UT       3.00         2.00         2.67

Rationale: G1 (Minor) geomagnetic storms are likely over 17 Nov due to a
combination of a influence from a CME that left the Sun on 14 Nov and
the anticipated influence of a negative polarity coronal hole.

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 Nov 17-Nov 19 2025

              Nov 17  Nov 18  Nov 19
S1 or greater   10%      1%      1%

Rationale: There exists a slight chance for S1 (Minor) or greater solar
radiation storms over 17 Nov due to potential from Region 4274 as it
rotates further around the Suns W limb.

C. NOAA Radio Blackout Activity and Forecast

Radio blackouts reaching the R1 levels were observed over the past 24
hours. The largest was at Nov 16 2025 0817 UTC.

Radio Blackout Forecast for Nov 17-Nov 19 2025

              Nov 17        Nov 18        Nov 19
R1-R2           55%           20%           10%
R3 or greater   15%            1%            1%

Rationale: R1-R2 (Minor-Moderate) radio blackouts are are likely, with a
slight chance for R3 (Strong), over 17 Nov due to the flare potential
from Region 4274 just beyond the the Suns W limb. Only a slight chance
remains for R1 events by 19 Nov.