Geomagnetic storm warning today (in addition to flooding)

:Issued: 2023 Mar 24 1230 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 8 (NOAA Scale
G4).
The greatest expected 3 hr Kp for Mar 24-Mar 26 2023 is 7.67 (NOAA Scale
G4).

NOAA Kp index breakdown Mar 24-Mar 26 2023

             Mar 24       Mar 25       Mar 26
00-03UT       6.67 (G3)    3.67         2.67     
03-06UT       7.67 (G4)    4.67 (G1)    3.33     
06-09UT       6.67 (G3)    4.33         4.67 (G1)
09-12UT       4.33         4.00         3.67     
12-15UT       4.67 (G1)    4.00         3.67     
15-18UT       5.67 (G2)    4.00         3.33     
18-21UT       2.67         4.33         3.00     
21-00UT       3.67         4.33         3.00     

Rationale: G4 (Severe) geomagnetic storms occurred early on 24 Mar due
to effects from CME passage. G1-G2 (Minor to Moderate) geomagnetic
storms are likely on 25-26 Mar due to CH HSS 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 Mar 24-Mar 26 2023

              Mar 24  Mar 25  Mar 26
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 Mar 24-Mar 26 2023

              Mar 24        Mar 25        Mar 26
R1-R2           10%           10%           10%
R3 or greater    1%            1%            1%

Rationale: There is a slight chance for R1-R2 (Minor-Moderate) radio
blackouts on 24-26 Mar.