Will skies be clear over southern Ontario Sunday night?
Mostly clear skies are likely, except for some mid and high-level clouds likely to appear occasionally over most regions, caused by some high and mid-level moisture which is forecast to be over southern Ontario (illustrated below for mid-evening). Also, more extensive low-level cloudiness is likely over regions south and east of Lake Huron and Georgian Bay.

Will skies be clear over southern Ontario Wednesday night? Mostly clear skies are likely except for some cloudiness due to low-level moisture over regions south and east of Lake Huron and Georgian Bay (illustrated below for early evening).

Will skies be clear over southern Ontario Tuesday night?
Mostly clear skies are likely, except for occasional periods of partly or mostly cloudy sky with low clouds, especially over regions east of Lake Huron.

Will skies be clear over southern Ontario Monday night?
Mostly clear skies are likely, except for occasional periods of partly or mostly cloudy sky with low clouds, especially over regions east of Lake Huron.

Will skies be clear over southern Ontario Saturday night?
Mostly cloudy skies are expected due to extensive low-level moisture which is forecast to be over southern Ontario overnight (illustrated below for early evening). Partly cleraring skies may appear around sunset and early evening over some regions, but mostly cloudy skies seem likely over most regions.

Will skies be clear over southern Ontario Wednesday night?

Partly or mostly clear skies are expected over some regions during the evening, except for more mid-level cloudiness over southwestern regions and some low-level cloudiness that may persist during early evening over regions south and east of Lake Huron and Georgian Bay. Later in the evening and overnight, increasing mid-level cloudiness is expected due to mid-level moisture which is forecast to move eastward over southern Ontario overnight (illustrated below for mid-evening).

Will skies be clear over southern Ontario Tuesday night?

Mostly clear skies are expected during the first several hours after sunset, and then partly cloudy skies are expected over some regions, due to low-level moisture which is forecast to move southward over southern Ontario during the evening (illustrated below for mid-evening).

Will skies be clear over southern Ontario Saturday night?
Mostly cloudy skies are expected over most regions, except for clear skies approximately north and east of Toronto and the GTA, due to a region of moisture which is forecast to be over most of southern Ontario overnight (illustrated below for early evening).

Will skies be clear over southern Ontario Friday night?

Skies are likely to become partly or mostly clear during the evening over many regions, and then become mostly cloudy after midnight, due to a break in mid-level moisture which is forecast to be over southern Ontario overnight (illustrated below for late evening).

Will skies be clear over southern Ontario Thursday night?
Mostly clear skies are likely, except for some areas of low cloudiness, especially over regions south and east of Georgian Bay and Lake Huron, and then more extensive low cloud is likely to develop over most regions before morning.

Will skies be clear over southern Ontario Wednesday night?

Cloudy skies are expected until early morning, and then skies are likely to become clear several hours before sunrise.

Will skies be clear over southern Ontario Tuesday night?

Mostly cloudy skies are likely during the evening, due to lots of low-level cloudiness caused by widespread low-level moisture which is forecast to be over southern Ontario overnight (illustrated below for early evening) and then decreasing cloudiness is likely by late evening and overnight as the moisture gradually moves eastward.

Will skies be clear over southern Ontario Sunday night?
Skies are likely to be mostly clear during the evening except for some high clouds caused by some high-level moisture which is forecast to move over southern Ontario overnight (illustrated below for early evening), and then increasing high cloud is expected during the night, followed by increasing low-level cloudiness over most southwestern regions before sunrise.

Will skies be clear over southern Ontario Saturday night?

Mostly cloudy skies are expected, due to widespread mid and high-level moisture causing lots of high cloudiness, but the full moon will likely be visible at least some of the time and may give the appearance of clearing skies. Clearing skies are likely during early Sunday as the moisture moves eastward from southwestern Ontario (illustrated below for early Sunday morning) and most regions may become clear before sunrise.

Will skies be clear over southern Ontario Wednesday night?

Mostly clear skies are likely until early morning, and then high clouds are likely to appear over most regions as increasing jetstream-level moisture (illustrated below for early Thursday) moves eastward over southern Ontario ahead of Thursday night’s low pressure trough.

Will skies be clear over southern Ontario Tuesday night?
Skies will likely be partly clear over regions near western Lake Ontario during the first couple of hours after sunset, and then become cloudy during early evening, followed by partly clearing skies after midnight. Further west, over southwestern regions, cloudy skies during the evening are likely to begin clearing around midnight. The illustration below shows the low-level moisture forecast during early evening.

Will skies be clear over southern Ontario Monday night?

Skies are likely to be partly cloudy, due to lots of high-level moisture (illustrated below for early evening) causing scattered high cloud that should be easily visible in the bright moonlight before midnight, while the brighter stars may give the appearance of mostly clear skies during the periods with less clouds.

Will skies be clear over southern Ontario Thursday night?

Clearing skies are likely after sunset, except for lots of low-level clouds over regions south and east of Lake Huron and Georgian Bay, and except for some mid- and high-level cloud that may occasionally appear overnight, due to the presence of some moisture at all levels in the atmosphere over southern Ontario overnight.

Will skies be clear over southern Ontario Wednesday night?

Skies are likely to be partly clear with some low clouds during the early evening over most regions, except for more cloudiness over regions south and east of Lake Huron and Georgian Bay. Then, increasing mid-level cloudiness is expected by mid or late evening, due to increasing mid-level moisture which is forecast to move eastward over southern Ontario overnight (illustrated below for mid-evening) ahead of Thursday’s low pressure trough.

Will skies be clear over southern Ontario Tuesday night?

Cloudy skies are expected during the evening, and then mostly cloudy skies are expected following Tuesday night’s cold front, except for gradually increasing clear breaks in the low cloud that will likely provide some clear breaks before morning over most regions.

Will skies be clear over southern Ontario Monday night?
Mostly clear skies are likely, except for high cloud which is likely to appear over most regions due to jetstream-level moisture which is forecast to move over southern Ontario overnight (illustrated below for mid-evening) as well as some low-level clouds which may appear over some locations especially during early evening.

Will skies be clear over southern Ontario Sunday night?
Skies are likely to be mostly cloudy, due to widespread low-level moisture (illustrated below for mid-evening) causing low clouds, but breaks in the cloud are likely and so some periods of partly or mostly clear sky are likely to appear occasionally over most regions.

Will skies be clear over southern Ontario Thursday night?

Mostly cloudy skies are likely before midnight over most regions, especially south of Lake Huron and Georgian Bay, due to low-level moisture (illustrated below for mid-evening) and then gradually clearing skies are likely during the early morning.

Will skies be clear over southern Ontario Tuesday night?
Mostly cloudy skies are likely most of the time over most regions, due to lots of low-level moisture which is forecast to be over southern Ontario (illustrated below for mid-evening) but breaks in the cloud may appear from time to time overnight and allow skies to become partly or mostly clear over various regions.

Will skies be clear over southern Ontario Friday night?

Clear skies are likely over most regions during the evening, except for some scatted low clouds caused by low-level moisture especially south of Georgian Bay and Lake Huron (illustrated below for early evening), and then increasing mid-level cloudiness is expected after midnight due to mid-level moisture which is forecast to move eastward over southern Ontario (illustrated below for early Saturday).

Will skies be clear over southern Ontario Wednesday night?

Mostly clear skies are expected over most regions, except for some low clouds that may appear, especially over regions east of Lake Huron, due to low-level moisture (illustrated below for mid-evening).

Will skies be clear over southern Ontario Tuesday night?
Partly clear and partly cloudy skies are expected, due to clearing ahead of a large high pressure ridge west of the Great Lakes, but partly cloudy due to lots of low-level moisture over southern Ontario (illustrated below for early evening) especially south and east of Lake Huron and Georgian Bay.

Will skies be clear over southern Ontario Monday night?

Lots of cloudiness is likely, due to lots of moisture which is forecast to move across southern Ontario (illustrated below for mid-level moisture during early evening), but many breaks in the cloudiness are likely to result in skies occasionally appearing to be clear enough for the bright moonlight to be visible and to give the impression of clear skies.

Will skies be clear over southern Ontario Friday night?
Mostly clear skies are likely during early evening, except for some high jetstream-level cloud over southwestern regions, followed by increasing high cloudiness by late evening due to increasing high-level moisture which is forecast to move over southern Ontario overnight (illustrated below for late evening), and then lower clouds are expected after midnight.

Will skies be clear over southern Ontario Monday night?

Skies may be clear occasionally over most regions, but lots of low and mid-level moisture is forecast to be over southern Ontario (illustrated below for late evening) and will likely cause lots of cloudy periods over most regions. Regions east of Lake Huron and Georgian Bay are more likely to be under mostly cloudy skies due to more extensive and widespread moisture over these regions.

Will skies be clear over southern Ontario Friday night?
Mostly cloudy skies are expected, except for partly clear skies near Lake Ontario during the first several hours after sunset, until mid-level moisture (illustrated below for early evening), moves eastward and causes increasing cloudiness by about mid-evening.

Will skies be clear over southern Ontario Thursday night?
Mostly clear skies are expected during early evening and then gradually increasing high and mid-level moisture (illustrated below for early and late evening) is expected to cause increasing cloudiness overnight.

Will skies be clear over southern Ontario Wednesday night?
Mostly clear skies are likely, except for cloudiness over regions south and east of Lake Huron and Georgian Bay overnight.

Will skies be clear over southern Ontario Friday night?
Mostly clear skies are expected, except for thin high cloud that may appear occasionally over most or all regions, due to jetstream-level moisture which is forecast to move over southern Ontario overnight (illustrated below for early evening).

Will skies be clear over southern Ontario Thursday night?
Mostly clear skies are likely, except for some thin high cloud that may appear over some regions, due to some thin high-level moisture that is forecast to move over southern Ontario overnight (illustrated below for late evening).

Wednesday night, clear skies!

Tuesday night., clear skies!

Will skies be clear over southern Ontario Monday night?
Mostly clear skies are expected, except for mostly cloudy skies over some southwestern regions during the evening due to low-level moisture (illustrated below for late evening) which is forecast to be over southwestern Ontario and is likely to cause cloudiness during the first half of the night over southwestern regions, and some low clouds over other regions of southern Ontario.

Will skies be clear over southern Ontario Friday night?
Partly clear skies are likely during the evening over most regions, followed by increasing cloudiness after midnight, when substantial mid-level moisture is forecast to move eastward over southern Ontario (illustrated below for late evening).

Will skies be clear over southern Ontario Monday night?
Clear skies are expected, except for some low clouds that may appear occasionally, especially early in the evening.

Will skies be clear over southern Ontario Saturday night?
Skies are likely to be clear over many regions for several hours after sunset, until increasing mid and high-level moisture moves eastward over southern Ontario by late evening (illustrated below for early evening) ahead of tonight's cold front and causes cloudy skies before midnight.

Will skies be clear over southern Ontario Thursday night?
Increasing cloudiness is expected, due to increasing mid and high-level moisture which is forecast to move eastward over most regions by late evening (illustrated below for late evening) although skies might appear to be mostly clear during early evening with the bright full Harvest Moon brightening the sky.

Will skies be clear over southern Ontario Wednesday night?
Clear skies are expected by mid or late evening over southern regions, following the eastward movement of mid-level moisture from southern Ontario (illustrated below for early evening).

Will skies be clear over southern Ontario Tuesday night?
Mostly clear skies are likely during the evening, and then increasing mid-level cloudiness is expected to spread over southern Ontario after midnight, caused by a region of mid-level moisture ahead of Wednesday's cold front (illustrated below for late Tuesday evening) and then mostly cloudy skies are likely by morning.

Will skies be clear over southern Ontario Monday night?
Partly clear skies are expected due to lots of upper-level moisture (illustrated below for late evening) which will likely be causing high thin cloudiness over many regions that may be visible in the bright moonlight.

Will skies be clear Sunday night over southern Ontario?
Mostly clear skies are expected, except for some thin high clouds that may appear occasionally over some regions.

Saturday night: clear skies will be caused by a big high pressure ridge and clear, dry air over southern Ontario.

Will skies be clear over southern Ontario Friday night?

Clearing skies are expected over some regions, after moisture moves eastward with a low pressure region (illustrated below for low-level moisture during late evening), but regions near Lake Ontario and the GTHA are likely to remain cloudy until after midnight and then clouds are likely to persist over regions south of Lake Huron and Georgian Bay overnight.

Will skies be clear over southern Ontario Thursday night?
Mostly clear skies are expected, except for some low and mid-level clouds that may appear occasionally.

Will skies be clear over southern Ontario Wednesday night?
Mostly clear skies are likely except for some low and mid-level clouds that may be visible during early evening.

Will skies be clear Tuesday night over southern Ontario?
Mostly clear skies are expected, except for some patches of mid-level clouds that may occasionally appear over most regions.

Saturday night: clear skies are expected.

Will skies be clear over southern Ontario Friday?
Clear skies are expected, except for some thin high cloud that is spreading northward over regions north of Lakes Erie and Ontario.

Will skies be clear over southern Ontario Thursday night?
Partly clear skies are expected, with some clouds likely to be in the sky over most regions, caused by a region of mid-level moisture which is forecast to move eastward over southern Ontario overnight (illustrated below for late evening).

Will skies be clear over southern Ontario Wednesday night?
Mostly clear skies are likely and some clouds are likely to appear over some regions, due to some mid-level moisture which is forecast to be over southern Ontario overnight (illustrated below for late evening). Fog is also likely to develop over many areas.

Will skies be clear over southern Ontario Tuesday night?
Mostly cloudy skies are likely, due to lots of moisture in the atmosphere over southern Ontario, but some areas of less cloudiness may allow the brighter stars to become visible and give the impression of partly clear skies. The high humidity is likely to contribute to fog formation overnight.

Note: no posts will be updated until Tuesday, September 19.
Clear skies!

Will skies be clear over southern Ontario Thursday night?

Mostly clear skies are expected over most regions, except for some low-level cloudiness in regions near the GTA during the evening, until low-level moisture (illustrated below for late evening) is forecast to diminish and allow skies to become clear. Fog is likely to form before morning in many regions and the high humidity will cause significant dew during the night.

Will skies be clear over southern Ontario Wednesday night?
Mostly cloudy skies are expected, due to moisture from the storm south of Ontario that was Hurricane Irma, but gaps in the moisture may allow occasional periods of partly clear skies over some regions (especially northern regions closer to Georgian Bay than Lake Erie) overnight that may be clear enough to allow aurora to be seen if the aurora becomes active.

Will skies be clear over southern Ontario Tuesday night?

Mostly cloudy skies are likely over southwestern regions, due to high-level clouds moving north ahead of post-tropical storm Irma, while mostly clear skies are likely further north over northern regions of southern Ontario (approximately north of Lake Ontario, depending on how far north the high clouds remain visible during the night).

Will skies be clear over southern Ontario Monday night?

Partly clear skies are expected, due to dry air associated with a strong high pressure ridge over Ontario, except for high-level clouds that will likely be spreading northward from Tropical Storm Irma and will probably be visible over southern regions during most of the night and over most other regions during at least part of the night.

Note, no more posts will be updated until Monday September 11 (due to vacation).

Will skies be clear over southern Ontario Friday night?
Mostly cloudy skies are expected over most southern regions, due to high-level cloudiness spreading northward over southern Ontario ahead of the remnant of Hurricane Harvey, illustrated below. The high cloudiness may occasionally be thin enough to allow the moon and brighter stars to give the impression of clear skies over some regions. Some northern regions are likely to remain mostly clear, depending on how far northward the high cloud can spread before getting dispersed in the high pressure ridge over northern Ontario.

Will skies be clear over southern Ontario Thursday night?
Clear skies are expected over most regions, except for high cloud that is likely to spread northward over southwestern regions before morning caused by the leading band of high cloud ahead of the remnant of ex-hurricane Harvey (illustrated below for early Friday morning).

Will skies be clear over southern Ontario Wednesday night?
Partly or mostly clear skies are expected for several hours during the evening over most regions, after daytime clouds diminish after sunset and before widespread low-level and mid-level moisture moves southward over southern Ontario around midnight (illustrated below for late evening).

Will skies be clear Tuesday night over southern Ontario?
Skies are likely to appear mostly cloudy during the evening due to lots of mid-level and jetstream-level moisture (illustrated below for late evening) which is forecast to gradually diminish by early Wednesday. The moon and brighter planets and stars may be visible during the evening and give the impression of clear skies in some regions where cloud cover becomes thin.

Will skies be clear over southern Ontario Sunday night?
Skies are likely to appear mostly cloudy due to increasing high and mid-level cloudiness, although the moon and brighter stars and planets may be visible and give the impression of partly clear skies during the evening.

Will skies be clear over southern Ontario Saturday night?
Mostly clear skies are expected except for increasing high cloudiness over southwestern regions by sunset and during early evening, caused by high-level moisture which is forecast to spread eastward over southern Ontario overnight (illustrated below for late evening).