Geomagnetic Storm Forecast

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3-Day Forecast - 2023 Apr 21 0030 UTC

:Product: 3-Day Forecast
:Issued: 2023 Apr 21 0030 UTC
# Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center
#
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 21-Apr 23 2023 is 4.67 (NOAA Scale
G1).

NOAA Kp index breakdown Apr 21-Apr 23 2023

             Apr 21       Apr 22       Apr 23
00-03UT       4.33         3.33         3.00     
03-06UT       4.67 (G1)    3.67         2.00     
06-09UT       4.00         3.00         2.00     
09-12UT       3.33         3.00         2.67     
12-15UT       3.00         3.00         2.67     
15-18UT       1.67         2.00         2.67     
18-21UT       2.00         3.33         2.67     
21-00UT       3.00         3.33         3.00     

Rationale: G1 (Minor) geomagnetic storms are likely on 21 April due to
possible CME influences.

B. NOAA Solar Radiation Activity Observation and Forecast

Solar radiation, as observed by NOAA GOES-16 over the past 24 hours, was
below S-scale storm level thresholds.

Solar Radiation Storm Forecast for Apr 21-Apr 23 2023

              Apr 21  Apr 22  Apr 23
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 Apr 21-Apr 23 2023

              Apr 21        Apr 22        Apr 23
R1-R2           35%           30%           30%
R3 or greater    1%            1%            1%

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

3-Day Forecast - 2023 Apr 20 0030 UTC

:Product: 3-Day Forecast
:Issued: 2023 Apr 20 0030 UTC
# Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center
#
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 Apr 20-Apr 22 2023 is 4.67 (NOAA Scale
G1).

NOAA Kp index breakdown Apr 20-Apr 22 2023

             Apr 20       Apr 21       Apr 22
00-03UT       2.67         4.33         3.33     
03-06UT       3.00         4.00         3.67     
06-09UT       2.67         3.33         3.00     
09-12UT       2.67         3.00         3.00     
12-15UT       4.33         3.00         3.00     
15-18UT       4.67 (G1)    1.67         2.00     
18-21UT       4.67 (G1)    2.00         3.33     
21-00UT       4.00         2.00         3.33     

Rationale: G1 (Minor) geomagnetic storms are likely on 20 Apr due to
possible CME influences.

B. NOAA Solar Radiation Activity Observation and Forecast

Solar radiation, as observed by NOAA GOES-16 over the past 24 hours, was
below S-scale storm level thresholds.

Solar Radiation Storm Forecast for Apr 20-Apr 22 2023

              Apr 20  Apr 21  Apr 22
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 Apr 20-Apr 22 2023

              Apr 20        Apr 21        Apr 22
R1-R2           35%           35%           35%
R3 or greater    1%            1%            1%

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

3-Day Forecast - 2023 Apr 19 0030 UTC

:Product: 3-Day Forecast
:Issued: 2023 Apr 19 0030 UTC
# Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center
#
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 Apr 19-Apr 21 2023 is 5.00 (NOAA Scale
G1).

NOAA Kp index breakdown Apr 19-Apr 21 2023

             Apr 19       Apr 20       Apr 21
00-03UT       5.00 (G1)    2.67         4.33     
03-06UT       4.33         3.00         4.00     
06-09UT       4.00         2.67         3.33     
09-12UT       3.33         2.67         3.00     
12-15UT       2.67         4.67 (G1)    3.00     
15-18UT       2.00         4.67 (G1)    1.67     
18-21UT       2.00         4.33         2.00     
21-00UT       2.33         4.00         2.00     

Rationale: G1 (Minor) geomagnetic storms are likely on 19-20 Apr due to
CME influences.

B. NOAA Solar Radiation Activity Observation and Forecast

Solar radiation, as observed by NOAA GOES-16 over the past 24 hours, was
below S-scale storm level thresholds.

Solar Radiation Storm Forecast for Apr 19-Apr 21 2023

              Apr 19  Apr 20  Apr 21
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

No radio blackouts were observed over the past 24 hours.

Radio Blackout Forecast for Apr 19-Apr 21 2023

              Apr 19        Apr 20        Apr 21
R1-R2           40%           40%           40%
R3 or greater   10%           10%           10%

Rationale: There is a chance for R1-R2 (Minor-Moderate) radio blackouts,
and a slight chance for R3 (Strong) or greater radio blackouts all three
days.
                        

3-Day Forecast - 2023 Apr 18 0030 UTC

:Product: 3-Day Forecast
:Issued: 2023 Apr 18 0030 UTC
# Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center
#
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 2023 is 1.67 (below NOAA
Scale levels).

NOAA Kp index breakdown Apr 18-Apr 20 2023

             Apr 18       Apr 19       Apr 20
00-03UT       1.67         1.33         1.67     
03-06UT       1.33         1.33         1.67     
06-09UT       1.00         1.33         1.67     
09-12UT       0.67         1.33         1.33     
12-15UT       0.33         1.67         1.33     
15-18UT       1.00         1.33         1.33     
18-21UT       1.33         1.67         1.33     
21-00UT       1.67         1.67         1.33     

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-16 over the past 24 hours, was
below S-scale storm level thresholds.

Solar Radiation Storm Forecast for Apr 18-Apr 20 2023

              Apr 18  Apr 19  Apr 20
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

No radio blackouts were observed over the past 24 hours.

Radio Blackout Forecast for Apr 18-Apr 20 2023

              Apr 18        Apr 19        Apr 20
R1-R2           45%           45%           45%
R3 or greater   10%           10%           10%

Rationale: There is a chance for R1-R2 (Minor-Moderate) radio blackouts,
and a slight chance for R3 (Strong) or greater radio blackouts all three
days.
                        

3-Day Forecast - 2023 Apr 17 0030 UTC

:Product: 3-Day Forecast
:Issued: 2023 Apr 17 0030 UTC
# Prepared by the U.S. Dept. of Commerce, NOAA, Space Weather Prediction Center
#
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 17-Apr 19 2023 is 1.67 (below NOAA
Scale levels).

NOAA Kp index breakdown Apr 17-Apr 19 2023

             Apr 17       Apr 18       Apr 19
00-03UT       1.67         1.67         1.33     
03-06UT       1.33         1.67         1.33     
06-09UT       1.33         1.33         1.33     
09-12UT       1.33         1.33         1.33     
12-15UT       1.33         1.33         1.67     
15-18UT       1.67         1.33         1.33     
18-21UT       1.33         1.67         1.67     
21-00UT       1.67         1.33         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-16 over the past 24 hours, was
below S-scale storm level thresholds.

Solar Radiation Storm Forecast for Apr 17-Apr 19 2023

              Apr 17  Apr 18  Apr 19
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

No radio blackouts were observed over the past 24 hours.

Radio Blackout Forecast for Apr 17-Apr 19 2023

              Apr 17        Apr 18        Apr 19
R1-R2           50%           50%           50%
R3 or greater   10%           10%           10%

Rationale: There is a chance for R1-R2 (Minor-Moderate) radio blackouts
and a slight chance for R3 (Strong) or greater radio blackouts on Apr
17-19.
                        

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