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000
FXXX10 KWNP 211233
DAYTDF

:Product: 3-Day Forecast
:Issued: 2024 Apr 21 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 3 (below NOAA
Scale levels).
The greatest expected 3 hr Kp for Apr 21-Apr 23 2024 is 3.67 (below NOAA
Scale levels).

NOAA Kp index breakdown Apr 21-Apr 23 2024

             Apr 21       Apr 22       Apr 23
00-03UT       3.00         2.33         2.33
03-06UT       3.00         2.67         3.00
06-09UT       3.33         2.00         3.67
09-12UT       3.33         2.33         3.67
12-15UT       3.67         2.00         2.67
15-18UT       2.67         1.67         2.67
18-21UT       2.00         1.67         2.67
21-00UT       2.00         2.33         3.00

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 Apr 21-Apr 23 2024

              Apr 21  Apr 22  Apr 23
S1 or greater   15%     15%     15%

Rationale: There is a slight chance for S1 (Minor) solar radiation
storms over 21-23 Apr due to the flare potential of several active
regions on the visible disk.

C. NOAA Radio Blackout Activity and Forecast

No radio blackouts were observed over the past 24 hours.

Radio Blackout Forecast for Apr 21-Apr 23 2024

              Apr 21        Apr 22        Apr 23
R1-R2           55%           55%           55%
R3 or greater   15%           15%           15%

Rationale: R1-R2 (Minor-Moderate) radio blackouts are likely, with a
slight chance for R3 (Strong) or greater events, over 21-23 Apr due to
the flare potential of several active regions on the visible disk.