Crisp & Clean With No Caffeine

Cold Front went through Sunday and in it's wake MUCH Cooler, Drier Arctic Air has descended down across BC & Alberta. That drier air mass helped clear out our stubborn low overcast and fog, but it has also cooled things down. The temperature inversion that helped keep us on cloud "lockdown" is no longer in place so expect cooler temperatures as you climb up through any of the mountain passes.

Pennask & Elkhart Summits received snow yesterday, so we are back to winter driving conditions in the mountains; be prepared.

Expect sunny and seasonally cool conditions early this week. A nice Frontal system is getting organised offshore in the Pacific and that will affect the Southern Interior Wednesday with more cloud and the slight risk of an evening shower. Although unsettled around Hallow e'en...Right now it looks dry Thursday evening for the Okanagan Trick or Treaters.

Enjoy the SUN ... Dootin Do Do.

A Change This Weekend

It's FRIDAY!!! A pattern change this weekend will break down the inversion and we can finally return to a more typical Fall pattern.

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A shortwave trough will glide down the east side of the upper ridge this weekend and an associated modified arctic front will help bring cool air to the upper levels over the Southern Interior.

By next week the fog will be gone and we will see frost once again in the mornings.

Until then, today and tomorrow will be similar with mainly cloudy conditions below 1100 metres with highs between 8-10C, but higher elevations will be in the sun and at least a few degrees warmer than areas in the valley.  

This front will also bring the chance of showers to parts of the Interior on Sunday. 

 

Fog Fix

Mother Nature is making sure we get our fog fix this October.

The winds continue to be light and an inversion is still in place, keeping this stubborn fog in the forecast.  On the right is a "skew-t" diagram, a great method of getting a quick glace at how stable or unstable the atmosphere is.  No suprise - but we have a very stable scenario here as a very obvious inversion is in place.  At first glance you can notice two solid black lines. The one on the right is the temperature and the one on the left represents the dew point. Although the temperature line starts off by going to the left at first, at around 830m or 925mb, the line then heads to the right - illustrating that the temperatures get warmer with height. At 5pm this morning, the weather balloon reported 6 degrees at the bottom of hte valley and 10 degrees at 1800 meteres.  

We continue to sound like a broken record but this blocking pattern mean very little changes in the forecast.  With the inversion holding so strong, most areas in the Shuswap, Arrow Lakes, North Okanagan and the Central Okanagan are not seeing much afternoon clearing (if any) keeping daily highs between 8 and 10 degrees. However the Southern Okanagan and the Boundary regions are much drier and the lack of fog has allowed temperatures to be well above seasonal with highs between 13-17 degrees.   

With all this said- models are continuing to suggest a gradual pattern shift starting Thursday when the ridge flattens. By the weekend an upper trough will move through our region bringing in cool air to replace the warm air aloft. Showers are likely to move through the Southern Interior on Sunday.  

 

Make Outdoor Plans

 Here in the Southern Interior we continue to remain under the influence of a stabilizing Upper Ridge. It makes forecasting easy, but writing a weather blog difficult; there's only so many ways to say the weather is going to be nice :)

Here's a look at the latest satellite images with Upper Air Analysis. That stationary ridge will be our best friend for the next week or so in Southern BC. Dry conditions will prevail. A little more cloud Sun-Mon, but generally expect sunshine with overnight lows close to freezing and daytime highs around 13-15C. Morning fog / cloud with afternoon clearing. Beautiful fall weather. 

Make outdoor plans and enjoy. 

Hello High

A weak Cold Front passed over the Southern Interior last night and kicked up some llight showers for most regions. Now that it has passed and moved east over the Rockies, we can sit back and enjoy a stretch of stable weather. An unseasonably strong Upper Ridge will develope today that will dominate our weather pattern from now until Monday.

Expect afternoon clearing, then a mix of sun and cloud from Wednesday onward through the weekend. By Sunday the ridge will flatten briefly; expect more cloud with the possibility of showers Monday for Central BC. Southern portions of the province should stay dry and then we bounce back again next week

Daytime highs this week will be a couple of degrees above average. Enjoy the fine fall weather and make some outdoor plans.

"H" is for High and Happy Thanksgiving

A quick glance at the surface chart shows that pretty much all of Canada is covered in the letter "H".  Surface High Pressure is blanketing the country making for a Happy Thanksgiving.  Thanks letter "H".

Closer to home on the west coast, our weather will continue to be brought to you by the letter "H". A strong ridge of High Pressure will continue ot keep Southern BC under a dome of confidence; expect a mostly clear sky with daytime temps around 15C and overnight lows around freezing.

Tuesday afternoon we will see a little more cloud as a short wave through passes through the region but clearing will return Wednesday.

 

Thankful For Fine Fall Weather

The short version of the forecast is that Southern Interior BC will have fine weather this Thanksgiving Weekend.  Holiday Monday will be a good day to take a moment to be thankful for what you have as well as a comfortable walk outside.

However, the more detailed analysis shows that we are currently in a Northwesterly Flow at  the 500mb level...and you can never trust a NWly flow.

Surface map this morning shows a weak area of high pressure over the central coast, while at the same time, a weak surface low off the the south coast. Circulation around these two features if jamming up some low level moisture (Cloud) over the southern interior this morning. 

This situation will resolve itself today to bring a little sunshine into everyone's life in Southern BC. 

Expect increasing cloud Fri evening as a trough to the south enjoys a brief period of influence ... until our new best friend, the Long Weekend Ridge builds in for Sunday and Monday bringing with it sunshine and seasonal or even slightly above temperatures.

 

Chilly Start but Sunny Day Ahead

Clearing last night combined with a cool Northerly flow aloft helped temperatures drop below freezing in many areas throughout the BC Interior last night:

  • Clinton                        - 5.1C  (coolest spot in BC) 
  • Kelowna Airport       - 2.0C  
  • Merritt                         - 3.0C    \
  • Princeton                   - 1.8C

Close to freezing but not quite committing to the job:

  • Penticton   1.2 C
  • Vernon       1.6

Enhanced IR Satellite Image helps identify the well defined Cold Front sweeping across North Coastal BC. While a surface High will help stabilize the Southern Interior during the day, the tail of that Coastal Front will kiss the region overnight bringing cloud and the risk of a light shower.

On the plus side, with an overcast sky, overnight lows will stay on the plus side :)

Have a good day. 

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Monday Cold Front = Change

That was a nice fall weekend; Lytton was the hot spot in BC at 24.5C yesterday, but most regions in the southern interior got into at least the high teens under a sunny sky.

Fall weather patterns move quickly and a Cold Front passing over the province today will bring a noticeable shift to breezy / cooler conditions with rain and even wet snow for higher elevations. 

This mornings Satellite Image shows a Surface Low off the west coast of Vancouver Island that will encourage a trough of cool unstable air to organize in the wake of this weekend's warmer air.  The coast can expect increasing cloud today with showers and gusty winds with the passing of the Front. It will take until this evening for the system to cross the Southern Interior. The cooler air being drawn in from the Northwest will drop snow levels down to around 1300m overnight. Drivers should expect accumulating snow through the Pennask and Kootenay Summits and wet snow through the lower elevation mountain highways.

Today however will still bring some sunshine with increasing cloud later in the day. 

Unsettled Will Settle...

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The teacher has entered the room and like good students , the weather will become more settled today into tomorrow...for a short period of time. 

Fall weather patterns are often more dynamic and move faster than summer or winter, so whatever the weather this time of the year, the current system  will usually move out of town and be replaced by the next one relatively quickly. 

The problem the last couple of days is that wave after wave of cool air aloft and moisture has been caught up in our mid level flow. So, as one trough moves along quickly, it is replaced by another. This has resulted in our cloudy with showers, replaced by clearing, replaced by cloudy with showers, but always cool pattern this week.  

The cycle is about to be broken - for 2 days... 

A look at the Water Vapour Image helps appreciate the current movement of moisture in our atmosphere; Green areas are moist. while Dark areas are dry. 

A weak, short lived ridge will help stabilize our weather, dry things out, provide a little more sun and help warm things up a bit Thurs- Fri. As mentioned, patterns move quickly this time of year so the next front will push onshore with more rain Sat into Sunday. 

Blustery Night

That was a blustery night throughout the Southern Interior. I'm sure there are a few tired people at work today after Mother natures Sleep Deprivation Machine went through.

A Cool Upper Trough and a Surface Cold Front caught up in that flow, combined for gusty winds and thunderstorms last night. Winds gusted near 70km/h up through the Okanagan, accompanied by a period of rain (6-10mm) and lightening. 

Weather pattern will remain cool and breezy behind the front, with sunny breaks, but the worst of the rain is over for the central interior. Successive, weaker Surface Troughs, caught up in our dominant Upper Trough will bring waves of cloud between sunny breaks. The possibility of a very light short lived shower can't be ruled out completely, but the chances are slim the South Central Interior will receive much if any.

Snow at higher elevations

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A series of fronts will hit BC over the next few days. The weather systems are tapping into subtropical moisture all the way from the other side of the Pacific – Tropical Storm Pabuk is one of the energizers for the stormy weather this weekend.

This weather pattern will keep rain in the forecast from now until early next week for most areas across the province. Models predict 15-25mm of rain over the next three days for the Okanagan Valley, 20-50mm of rain for the Columbia and Arrow Lakes region, and if you’re heading to the South Coast for the weekend, rain amounts there will vary from 40-100mm of rain.

Please also use extra caution if travelling today as freezing levels this morning are about 1700m and as a result there is a bit a snow on the higher mountain passes including the Okanagan Connector.

 

Another Chilly Start

Once again, under the influence of a broad trough of cool air from the north, a clear sky permitted overnight lows to drop close to freezing in many areas of the Southern Interior this morning:
Kelowna Airport  0.6C
Merritt  -1.8C
Princeton Airport   -1.8C


This time of the the year, clear skies, no wind and cool temperatures is the recipe for morning fog, so be aware of the potential for slippery roads and patchy poor visibility on your morning commute outside of major cities.

Our trough of cool arctic air is digging southward into the Western US and the flow around that feature is nurturing the development of a significant weather system over the American Rockies. Lows will spin up and exit this trough northward up into the Canadian Prairies over the next day. Sheltered for the most part by the mountains to the east, South Central BC will receive periods of showers...

 Seasonal temperatures will continue this week with increasing cloud changing to showers Wednesday evening into Thursday morning. Some sunshine to start Friday, then a cloudy, rainy weekend is in store for us as a new system pushes in from the coast.

Fall lawn fertilization is recommended Friday afternoon :) 

 

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Like Clockwork

Like clockwork, the cool air that has flowed in behind the system that moved through the southern interior this weekend has made it feel like fall. The Autumnal Equinox officially occurred at 1:44pm on Sunday but you wouldn't need a calendar to tell you that the seasons have changed.

Cool, Breezy, Showery (with sunny breaks) Unsettled Fall-like weather is in the cards for us this week under the influence of a strong mid-level westerly flow. The "washboard" effect  on the visible satellite image over Washington this morning is indicative of these winds. They will help keep whatever type of weather that is happening moving quickly; So expect a bit of everything.

Cool but seasonal temperatures will prevail, but expect some clearing later today and Tuesday should be sunnier and dry. Our mid level flow pattern will guide a trough over the area on Wednesday then a weak ridge should help dry things out for next weekend, but don't expect these ridges to have the same warming influence that they do in the summer anymore.

Here Comes D-uane Again

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The forecast for the Southern Interior will be dominated by an approaching Cold Front. After another cool, clear night...Friday will be warm, sunny and dry. This will help set up the boundary between our warm/dry air and an approaching cooler/moist air mass.

Satellite imagery shows the position of the front draped along the entire BC Coast. As the system tracks east, the Southern Interior will see increasing cloud today ahead of the front.  Significant differences between the air masses will create the possibility of Thunderstorms with the passing of the front on Saturday. Expect gusty winds and if Thunderstorms don't spark up this at the very least rain to start early Saturday morning.

Like clockwork, cool showery conditions will continue through the weekend making the arrival of the Autumnal Equinox (Fall) at 1:44pm on Sunday feel like fall. 

Chilly Night...

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It was a chilly night last night throughout the interior... Princeton got down to 1.1 C and the Kelowna Airport saw temperatures drop down to 4.3 C.

As I was checking the radar yesterday, it was registering rain mixed with wet snow in the highest elevations of the Rockies. Word to the wise, if you travel the mountain passes we are now entering the time of year when you can leave summer-like conditions at lower elevations and drive into winter-like conditions as you head through the mountains.

On the cusp of Fall, our weather patterns are moving a little faster now, so our default High between systems won`t last very long. In the Southern Interior, expect a dry mix of sun & cloud for Thursday - Friday until the remnants of the next "winter-like" storm pushes over  the coast from the Northwest. By Friday evening we can expect more cloud to develop and light scattered rain showers to start Saturday morning. 

Behind the Cold Front, expect daytime highs to drop to into the mid teens. 

The Pause That Refreshes

Trough that brought rain and isolated Thundershowers through the interior yesterday evening has moved east of the Okanagan towards East Kootenay / Elk Valley. 

A short lived ridge will build in today for the Southern Interior, dry things out and bring some sunshine into Friday.

Next system is pushing in from the Pacific NW and will bring strong winds and rain for the coast. the remnants of this system will make its way to the southern interior by Saturday, so expect increasing cloud on Friday.  Expect cool and wet conditions this weekend.

Feels Like Fall...

Hi All... Wesla and I were out of town and busy the last few days and were not updated our blog. We're back in the saddle again here on Tues Sept.17, just in time to talk about cool, wet, breezy fall like conditions. 

Like clockwork, with the first day of fall only 5 days away, we are into a Trough of much cooler air ( the opposite of our Ridge last week), that will result in periods of unsettled cloudy, rainy weather. An Upper Cold Front will pass through the Southern Interior this evening, so expect rain and some gusty winds as front moves from east to west through the region. There is a slight chance of an isolated Thundershower along this front as well, but rain is a for sure.

A weak "default" High will establish itself behind the front, so Wed-Thurs looks a little better with more sun and seasonal temperatures. However, it "Falls" apart again for the end of the week. 

Next Verse...The Same as The First

Semi-Stationary Ridge in place is making forecasting pretty easy for BC. The big question is when will it break down, finally move east and open the door to cooler/wetter weather.

All signs point to Sunday afternoon for the beginning of the shift.

With the collapse of the ridge, a Cold Low will move out of the Gulf of Alaska (the  source of strong winter storms), track south along the BC coast and shift east Sunday into Monday. This will bring temperatures and conditions much more like fall. Expect a cool down with rain. 

This would be a good weekend to fall-fertilize your lawn; the rain early next week will water it in nicely.

 

Nothin' But Blue Skies Do I See...

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One of the products of  a a semi stationary Upper Ridge is a stretch of unchanging weather. As a result the forecast for today & the next couple will not change much. Dry, Stable, Warm conditions will prevail for regions under (south of) the ridge.

A look at the Water Vapour Image to the left makes it easy to see the arching ridge up over Northern BC and the separation between the Warmer/Dry air to the south of the ridge and the Cooler/Moister Air to the North.

Enjoy this stretch of warm late summer weather.