:Product: 04200030three_day_forecast.txt
:Issued: 2014 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 2014 is 6 (NOAA Scale
G2).

NOAA Kp index breakdown Apr 20-Apr 22 2014

            Apr 20     Apr 21     Apr 22
00-03UT        3          5 (G1)     4     
03-06UT        4          4          3     
06-09UT        3          4          2     
09-12UT        3          4          2     
12-15UT        5 (G1)     2          2     
15-18UT        6 (G2)     2          2     
18-21UT        5 (G1)     3          2     
21-00UT        5 (G1)     4          3     

Rationale: G1-G2 (Minor-Moderate) geomagnetic storms are likely on 20
Apr due to the anticipated arrival of a coronal mass ejection (CME) from
18 Apr.  G1 (Minor) geomagnetic storms are likely early on 21 Apr as CME
effects persist.

B. NOAA Solar Radiation Activity Observation and Forecast

Solar radiation, as observed by NOAA GOES-13 over the past 24 hours, was
above S-scale storm level thresholds.

Solar Radiation Storm Forecast for Apr 20-Apr 22 2014

              Apr 20  Apr 21  Apr 22
S1 or greater   99%     75%     50%

Rationale: The in-progress S1 (Minor) solar radiation storm that began
on 18 Apr is expected to continue for 20-21 Apr with a chance of
remaining at or above the S1 threshold on 22 Apr.

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 2014

              Apr 20        Apr 21        Apr 22
R1-R2           55%           50%           50%
R3 or greater   10%            5%            5%

Rationale: R1-R2 (Minor-Moderate) conditions are likely with a chance
for R3 or greater radio blackouts on 20 Apr due to active region flare
activity.  A chance for R1-R2 conditions exists for 21-22 Apr.