Thursday 31 July 2014

Will skies be clear Thursday evening over southern Ontario?

It looks like skies will be partly clear over most regions of southern Ontario, due to mid-level moisture that will be visible as mid-level clouds, and cause most locations to occasionally be under mostly clear skies and then occasionally under mostly cloudy skies.



Wednesday 30 July 2014

Will skies be clear over southern Ontario Wednesday evening?

It looks like skies may be clear during early evening and then partly cloudy later during the evening, with cloudiness earlier in southwestern regions and later in regions further east. The chart below shows mid-level moisture forecast to move southeastward across southern Ontario during the evening, and cyclonic curvature will be contributing to cause lift and result in some mid-level cloudiness. The moisture is forecast to move eastward from southwestern Ontario by morning, and so skies may begin clearing before dawn in southwestern regions.

Monday 28 July 2014

Will skies be clear over southern Ontario Monday night?

It looks like skies will become mostly clear during the night, but scattered patches of low-level cloud may exist during the evening and gradually diminish. Skies are more likely to be clear in southwestern regions and more likely to be partly clear further east, closer to the Toronto area.


Wednesday 23 July 2014

Will skies be clear over southern Ontario Wednesday night?

It looks like mostly clear skies are expected, except for some jetstream-level cirrus that may be visible as cloud over some regions, and except for some low-level cloud that may persist after sunset (until moisture in the lower levels of the atmosphere decreases around midnight).



Tuesday 22 July 2014

Will skies be clear over southern Ontario Tuesday evening?


It looks like clear skies are likely at sunset, followed by gradually increasing mid-level cloudiness ahead of a cold front that is moving southeastward across the Great Lakes region. So, regions further west and north (closer to Lake Huron) ought to see increasing cloudiness earlier, and locations further east and south (Niagara peninsula or east of GTA) may see clear skies longer.

Monday 21 July 2014

Will skies be clear Monday night over southern Ontario?
Clear skies are forecast.

Another detail that may affect skywatchers will be high humidity and calm winds, resulting in dew forming quickly on optical surfaces exposed to the sky.

Friday 18 July 2014

Will skies be clear Friday night over southern Ontario?
It looks like some high cirrus-level cloudiness will be over southern Ontario during the evening (shown below on the forecast chart for jetstream-level moisture), followed by increasing mid to high-level cloudiness during the night. During the evening, skies may appear mostly clear in some regions (especially northernmost regions, furthest from the thicker moisture layers). An extra complication is forest fire smoke plumes above southern Ontario during Friday that may add some haziness and cause reduced transparency, but not appear as cloud in the night sky.


Thursday 17 July 2014

Will skies be clear over southern Ontario Thursday night?
It looks like skies will become mostly or completely clear over most regions after sunset with dry air aloft and subsidence aloft ahead of a ridge building over the Great Lakes region. Afternoon cloudiness over some regions will be dissipating by or shortly after sunset.

Wednesday 16 July 2014

Will skies be clear Wednesday night over southern Ontario?
It looks like skies will become mostly clear during the evening. Afternoon cloudiness will begin to dissipate by sunset and skies ought to be mostly clear by an hour or so after sunset. Some mid-level cloudiness might be seen over some regions, caused by an area of mid-level moisture (pictured below) that is forecast to be over southern Ontario during the evening.

Tuesday 15 July 2014

Will skies be clear Tuesday night over southern Ontario?

It looks like partly or mostly clear skies are likely during the evening, with some mid-level moisture available to cause some mid-level cloudiness over some regions, especially closer to Lake Huron.

Sunday 13 July 2014

Will skies be clear over southern Ontario Sunday night?
It looks like clear skies are expected, except for some low-level cloudiness over some regions that may persist into the evening from Sunday afternoon low cloud formation.

Friday 11 July 2014

Will skies be clear over southern Ontario Friday night?
It looks like clear skies during Friday will persist into night, but some high jetstream-level cirrus will be over southern Ontario and will probably appear as visible high cloud in the bright moonlight, especially east of Toronto during the evening.



Thursday 10 July 2014



Will skies be clear over southern Ontario Thursday night?
High pressure ridge, clear skies!
(Bonus, dry air and winds from northeast-expect minimum dew formation.)

Wednesday 9 July 2014

Will skies be clear Thursday night over southern Ontario?
Mostly clear skies are expected! (Some low cloud will be persisting after sunset but diminish during the evening.)

Tuesday 8 July 2014



Will skies be clear Tuesday evening over southern Ontario?
It looks like skies will be clearing after sunset as moisture moves eastward. Clouds remaining from Tuesday afternoon’s thunderstorms might still be in the sky during twilight.

Sunday 6 July 2014

Will skies be clear Sunday evening over southern Ontario?
It looks like skies may be partly clear after sunset for southern parts of southern Ontario (near the lakes) but increasing mid-and high-level cloudiness is expected by late evening.

Saturday 5 July 2014

Will skies be clear Saturday night over southern Ontario?
Clear skies are expected over most regions, due to a high pressure ridge moving over southern Ontario, except for lots of high cloudiness over southwestern regions and the western Lake Erie area caused by a mid-level disturbance over the southern Great Lakes region.

Friday 4 July 2014

Will skies be clear over southern Ontario Friday evening?
It looks like skies will definitely be clear. Low dewpoints and light winds from the north will minimize dew formation.

Thursday 3 July 2014



Will skies be clear Thursday evening over southern Ontario?
It looks like clear skies ought to become clear over most of southern Ontario after sunset, except for some cloudiness during the early evening over the regions approximately east of Toronto, caused by an upper level trough moving eastward over southern Ontario during the afternoon.

Wednesday 2 July 2014



It looks like clearing skies, with dissipating thunderstorms being a big variable as some cloud remaining from afternoon thunderstorms will be sinking but may take several hours after sunset. The forecast chart below indicates some mid-level moisture over southern Ontario during late evening and this may appear as cloud, or the cloudiness may dissipate by an hour or more after sunset. So, clearing skies overnight (sometime).
 

Tuesday 1 July 2014

Will skies be clear over southern Ontario Tuesday evening?
It looks like mostly clear skies are likely and some clouds may be expected to appear over some or most regions, some of the time. Moisture will be present at middle-high levels in the atmosphere and may appear as clouds occasionally.
Dewpoint and humidity will be high at the surface and this will cause dew to form on optical surfaces exposed to a clear sky after sunset.