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000
FXXX10 KWNP 181231
DAYTDF

:Product: 3-Day Forecast
:Issued: 2024 Apr 18 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 Apr 18-Apr 20 2024 is 5.00 (NOAA Scale
G1).

NOAA Kp index breakdown Apr 18-Apr 20 2024

             Apr 18       Apr 19       Apr 20
00-03UT       1.67         3.00         2.67
03-06UT       0.67         3.00         2.00
06-09UT       0.33         2.67         2.00
09-12UT       1.00         2.33         2.33
12-15UT       2.67         2.00         2.67
15-18UT       4.00         2.00         3.00
18-21UT       5.00 (G1)    2.00         2.67
21-00UT       3.33         2.00         2.33

Rationale: An isolated G1 (Minor) storm period is likely on 18 Apr due
to the anticipated arrival of a CME from 15 Apr.

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 18-Apr 20 2024

              Apr 18  Apr 19  Apr 20
S1 or greater   20%     20%     20%

Rationale: There is a slight chance for S1 (Minor) solar radiation
storms over 18-20 Apr.

C. NOAA Radio Blackout Activity and Forecast

Radio blackouts reaching the R1 levels were observed over the past 24
hours. The largest was at Apr 18 2024 0248 UTC.

Radio Blackout Forecast for Apr 18-Apr 20 2024

              Apr 18        Apr 19        Apr 20
R1-R2           75%           75%           75%
R3 or greater   20%           20%           20%

Rationale: R1-R2 (Minor-Moderate) radio blackouts are expected, with a
slight chance for R3 (Strong) or greater events, over 18-20 Apr.