[RSM] W3LPLforecast wed thur June 16 - 17

[Arthur]

Begin forwarded message:

> Long distance propagation forecast for Wednesday and Thursday June 16-17
> 
> 
> 
> My propagation forecast derived from today's NOAA/SWPC
> 
> web pages is published five days a week (M-F) in the Daily DX.
> 
>  
> 
> Low latitude propagation is likely to be normal through Thursday.
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>  
> 
> Mid latitude propagation is likely to be normal through midday
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> Wednesday. Mild degradation is probable from midday Wednesday
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> through midday Thursday due to likely geomagnetic disturbance.
> 
> Mostly normal propagation is likely to return by midday Thursday.
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>  
> 
> Propagation through the auroral ovals and polar regions is likely
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> to be mostly normal through midday Wednesday. Moderate
> 
> degradation is likely from midday Wednesday through midday
> 
> Thursday due to likely geomagnetic disturbance. Mostly normal
> 
> propagation is likely to return by midday Thursday.
> 
>  
> 
> Click here for today’s latest planetary Kp Index, updated every three hours.
> 
> Click here for N0NBH’s current HF Band Conditions, updated regularly.
> 
>  
> 
> We are in the quiet geomagnetic activity season, only about half
> 
> as many geomagnetically disturbed days occur in June and July
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> compared to the more geomagnetically active equinox seasons.
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>  
> 
> Sporadic-E propagation occurs every day during June and July at
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> mid-latitudes in the northern hemisphere making long distance
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> propagation up to 15,000 km sporadically available in the
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> 17, 15, 12, 10 and 6 meter bands from sunrise through midnight
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> and occasionally somewhat later.
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>  
> 
> The solar flux index (SFI) is likely to be about 75 through Thursday.
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> One small isolated sunspot is having little effect on HF propagation.
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>  
> 
> 160 and 80 meter propagation from North America to VK/ZL and
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> the south Pacific is likely to be normal through Thursday. 40 meter
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> short path propagation to south Asia is likely to be below normal
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> at about 0015Z Thursday. 40 meter short path propagation from
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> North America to east Asia after about 0930Z is likely to be below
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> normal on Wednesday and mostly below normal on Thursday.
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>  
> 
> 30 meter propagation through the auroral ovals and polar regions
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> is likely to be mostly normal through midday Wednesday. Moderate
> 
> degradation.is probable from midday Wednesday through midday
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> Thursday due to likely geomagnetic disturbance. Mostly normal
> 
> propagation is likely to return by midday Thursday. 30 meter
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> propagation is always significantly degraded within a few hours
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> of local noon because of E-region blanketing of long distance F2
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> propagation. 30 meter night time long distance propagation in the
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> northern hemisphere is likely to improve due to increased ionizing
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> solar radiation in the northern high latitude regions caused by
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> higher solar elevation angles and much shorter nights with no source
> 
> of ionizing solar radiation.
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>  
> 
> 20 meter daytime and evening propagation through the auroral ovals
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> and polar regions is likely to be mostly normal through midday
> 
> Wednesday. Moderate degradation.is likely from midday Wednesday
> 
> through midday Thursday due to likely geomagnetic disturbance.
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> Mostly normal propagation is likely to return by midday Thursday.
> 
> 20 meter northern transpolar propagation within a few hours of
> 
> sunrise and sunset is improving with increased solar ionizing
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> radiation on the northern polar region caused by higher solar
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> elevation angles 24 hours per day during the midnight sun season.
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> 20 meter long distance propagation is significantly degraded from
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> mid-morning through late afternoon at low and mid-latitudes in the
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> northern hemisphere by F1 region midday blanketing of low angle
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> propagation during the summer. 20 meter nighttime long distance
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> propagation in the northern hemisphere is likely to improve due to
> 
> increased ionizing solar radiation in the northern high latitude
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> regions caused by higher solar elevation angles and much shorter
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> nights with no source of ionizing solar radiation.
> 
>  
> 
> 17 and 15 meter daytime long distance propagation in the northern
> 
> hemisphere is likely to improve due to increased ionizing solar
> 
> radiation in the northern high latitude regions caused by higher solar
> 
> elevation angles and longer days. 17, 15, 12, 10 and 6 meter
> 
> sporadic-E propagation up to 15,000 km is likely to be sporadically
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> available from sunrise through midnight and occasionally later
> 
> through late July.
> 
>  
> 
> Geomagnetic disturbances caused by coronal hole high speed
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> streams are likely to remain mostly brief, minor and somewhat
> 
> less frequent through at least late 2021. The southward oriented
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> (-Bz) component of the IMF plays a crucial but unpredictable role
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> in triggering all geomagnetic storms. Brief minor to moderate
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> geomagnetic storms may be gradually triggered when the IMF
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> persists in a southward orientation (-Bz) with enhanced IMF field
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> strength for several hours coincident with the effects of an Earth
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> directed coronal hole high speed stream. More frequent, longer
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> duration, minor to severe geomagnetic storms may be triggered
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> suddenly and unpredictably when the IMF persists in a southward
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> orientation (-Bz) with enhanced IMF field strength for several hours
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> or more coincident with the effects of an Earth directed fast CME.
> 
>  
> 
> IMF field strength, solar wind speed near Earth and geomagnetic
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> activity are likely to be at near ambient levels through midday
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> Wednesday. Moderate enhancement.is probable from midday
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> Wednesday through midday Thursday due to coronal hole
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> high speed stream influence. Near ambient levels are likely to
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> return by midday Thursday. A brief minor geomagnetic storm is
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> possible from late Wednesday through early Thursday. CME
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> and solar flare activity are not likely through Thursday.
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>  
> 
> Mid-latitude northern hemisphere sunset is now 74 minutes later
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> and daylength is 163 minutes longer than it was on the March 20th.
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> Daylength and solar elevation angle in the northern polar region
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> will remain mostly constant until late June due to summer solstice effects.
> 
>  
> 
> Click here for today’s Penticton 10.7 cm solar flux index updated at 1700Z, 2000Z and 2300Z daily.
> 
> Click here for today’s three-day GFZ Planetary K Index forecast updated every three hours.
> 
> Click here for today's SIDC Daily Bulletin on Solar and Geomagnetic Activity updated at 1230Z daily.
> 
> Click here for today's SWPC Solar Activity Forecast Discussion updated at 0030Z and 1230Z daily.
> 
> Click here for today's Australian Space Forecast Centre Summary and Forecast updated at 2330Z daily.
> 
>  
> 
> Perhaps the most useful HF propagation pages for DXers can be found at:
> 
> http://dx.qsl.net/propagation and http://www.solarham.net
> 
>