Archives for Tony

22nd October


Solar activity was low. Regions 1875 (N06E19, Ekc/beta-gamma-delta) and 1877 (S13E38, Cho/beta) were the most notable regions on the disk, and the most active. the largest event of the period was a C2/Sf, produced by Region 1875 at 21/2311 UTC. Additional analysis of the previously reported CMEs from 20 Oct suggests that two filament eruption-related events occurred during the past 36 hrs, both of which had potential for modest geoeffectiveness. Speed measurements of about 650 km/s and 430 km/s, respectively, were observed with the CMEs.

21st October


Tonight’s estimated aurora level:

Level 2 – Low

Forecast:
Auroral activity will be at low levels. Weather permitting, aurora displays may be visible overhead or on the horizon in Bodø (Norway), Sodankylä (Finland), Kiruna (Sweden) and Reykjavík (Iceland).

Comments:
CH HSS has been very weak so far, but is expected to increase today. There is also the possibilty of a faint CME brushing past earth while the CH HSS is active. More analysis is needed on that event.

20th October


Tonight’s estimated aurora level:

Level 2 – Low

Forecast:
Auroral activity will be at low levels. Weather permitting, aurora displays may be visible overhead or on the horizon in Bodø (Norway), Sodankylä (Finland), Kiruna (Sweden) and Reykjavík (Iceland).

Comments:
We should start to see the affects from a weak CH HSS late tonight. But for the most part, solar wind speed is expected to remain at nominal values. Solar wind will become slightly enhanced tomorrow and day after tomorrow (21 – 22 Oct) with weak CH HSS influence, which may spark nice shows in the far north (65°N+).

19th October


Level 1 – Quiet

Forecast:
Auroral activity will be at quiet levels. Weather permitting, aurora displays may be visible overhead or on the horizon in Tromsø (Norway) and Utsjoki (Finland).

Comments:
The geomagnetic field is expected to be at quiet levels for days one and two (19 – 20 Oct), increasing to quiet to unsettled levels with a chance for active conditions (kp4) on day three (21 Oct) due to CH HSS effects.

18th October


Level 1 – Quiet

Forecast:
Auroral activity will be at quiet levels. Weather permitting, aurora displays may be visible overhead or on the horizon in Tromsø (Norway) and Utsjoki (Finland).

Comments:
Geomagnetic activity has returned to quiet levels.

18th October


Solar wind parameters, measured at the ACE spacecraft, indicated a return to ambient conditions. Speeds steadily dropped from near 450 km/s at the beginning of the period to the current speeds of just under 370 km/s. IMF total field was again steady around 4 nT, while IMF Bz leveled off to end the period near zero. The IMF Phi angle remained at a positive (Away) orientation throughout the period.

17th October


Tonight’s estimated aurora level:

Level 2 – Low

Forecast:
Auroral activity will be at low levels. Weather permitting, aurora displays may be visible overhead or on the horizon in Bodø (Norway), Sodankylä (Finland), Kiruna (Sweden) and Reykjavík (Iceland).

Comments:

CME event was weak or missed earth. So we are left with weaking CH HSS affects. Not much aurora asctivity expected.

CME has gone AWOL


Where is the auroras?
So the much anticipated CME from Oct 13th M1.7 solar flare has gone missing. It was due to arrive last night and spark great aurora shows, but as yet there is no sign of it. Either it was VERY weak, or it is very late. There are some blips on the proton graphs which could indicate a weak CME brushed past earth, but NOAA SWPC had this forecast as a Kp4 event over the course of 12 hours or more. If this CME is late, ok, it happens, but if it is non existent or missed earth entirely. I think they need to re-calibrate their instruments.

We will know more later.

16th October


Solar wind parameters, measured at the ACE spacecraft, were indicative of coronal hole high-speed stream (CH HSS) influence. Speeds did, however, show signs of waning CH HSS effects, as they ranged from near
580 km/s at the beginning of the period to just over 480 km/s by the end of the period. IMF total field held steady at approximately 4 nT, while IMF Bz intermittently dipped southward as low as -4 nT. Phi angle
remained in a mostly positive (Away) orientation throughout the period.

16th October


Tonight’s estimated aurora level:

Level 4 – High

Forecast:
Auroral activity will be at high levels. Weather permitting, aurora displays will be visible overhead or on the horizon in Trondheim (Norway), Vaasa (Finland), Sundsvall (Sweden) and Faeroe Islands.

Comments:
CME from 13th Ocotber is due to arrive after 1800 UTC. It is only a weak-modest CME, but coupled with the activity we currently have from CH HSS, it has the potential to put on a nice aurora show.