SW BC Winter 2012-13 Options

[bigmt]

http://www.youtube.com/watch?v=m530uczsCk4...eature=youtu.be

Back to the norm...

Brett had a tweet about it as well - https://twitter.com/BrettAWX

 hytglh.png ( 13.22K ) Number of downloads: 0


18z GFS total precip @ hour 102:

 gfs_namer_102_precip_ptot.gif ( 62.28K ) Number of downloads: 1


Also, from the blog - http://www.accuweather.com/en/weather-blog...morning/7011534

Moist Pacific system will tack along western U.S./Canada border and has the potential to bring accumulating snow from central and southern Alberta to southern Saskatchewan later Sunday and Sunday night. I will address this more tomorrow.

[stuffradio]

When does Spring come?

[bigmt]

TWN - http://tinyurl.com/cyuqatf

February 27, 2013 — A system is coming ashore Thursday night, bringing up to 150 mm of rain to parts of the province.

Heavy rain is in the forecast for parts of B.C., starting Thursday evening.

"The downpour is expected to be steady until Saturday morning," says Gerald Cheng, a meteorologist at The Weather Network.

"The west coast of Vancouver Island could see up to 150 mm, while the south coast - including Metro Vancouver - could see up to 100 mm. While exact amounts may change, there will definitely be some rain."

Wind gusts may reach 30 – 50 km/h for the Strait of Georgia between Thursday afternoon and Friday morning.

Overall, it's been a fairly dry winter in B.C.

In January, total rainfall in Vancouver was 100.4 mm, versus an average of 139.1 mm for the month.

So far, the city has only see 58.2 mm of rain, compared with a February average of 113.8 mm.

When does Spring come?

It'll be interesting to see what the Euro weeklies show when Brett posts them. The CFS weeklies are modestly cool out to week 4 but the core of the colder anomalies is through the Prairies, extending into central Canada in week 3. Although wet for week 1 they are noticeably drier for weeks 2 and 3.

Euro weeklies > CFS weeklies however, IMO.

[bigmt]

Ouch.

https://twitter.com/BrettAWX

 hyoglfs.png ( 11.82K ) Number of downloads: 0

[stuffradio]

Ouch.

https://twitter.com/BrettAWX

 hyoglfs.png ( 11.82K ) Number of downloads: 0

Now can you understand why we just want Spring to come, which as usual, will be a chilly Spring with lots of rain...?

[bigmt]

Now can you understand why we just want Spring to come, which as usual, will be a chilly Spring with lots of rain...?

I intend to have a spring forecast out within the next few days FWIW but in the near-term the usually-reliable NAEFS is keeping chances for above-normal temps fairly high out to the middle of March:

 2013022800_054_007_E1_north_america_I_NAEFS_TEMPERATURE_anomaly_probability_combined_week2_198.png ( 47.51K ) Number of downloads: 0


My concern is that the western ridging can only last so long before it erodes, which is signaled by the PNA forecast:

 pna.sprd2.gif ( 6.34K ) Number of downloads: 0


Much of the problem with the winter was likely due to poor timing with the PNA as the stagnant western trough in the late-fall and early winter gave way to a modest but persistent +PNA for the period thereafter. No pattern can last forever so it does make some degree of sense that we would see a return to more of a western trough again at some point. That doesn't offer a lot of hope for the spring but seasonal forecasting is a bit of a shot in the dark and the farther ahead we look the less likely we are to be accurate.

[stuffradio]

I intend to have a spring forecast out within the next few days FWIW but in the near-term the usually-reliable NAEFS is keeping chances for above-normal temps fairly high out to the middle of March:

 2013022800_054_007_E1_north_america_I_NAEFS_TEMPERATURE_anomaly_probability_combined_week2_198.png ( 47.51K ) Number of downloads: 0


My concern is that the western ridging can only last so long before it erodes, which is signaled by the PNA forecast:

 pna.sprd2.gif ( 6.34K ) Number of downloads: 0


Much of the problem with the winter was likely due to poor timing with the PNA as the stagnant western trough in the late-fall and early winter gave way to a modest but persistent +PNA for the period thereafter. No pattern can last forever so it does make some degree of sense that we would see a return to more of a western trough again at some point. That doesn't offer a lot of hope for the spring but seasonal forecasting is a bit of a shot in the dark and the farther ahead we look the less likely we are to be accurate.

We have been getting at least a bit of rain almost every day for February. So it's not like this ridge has been giving us lots of sun. We're far below what we should be for number of hours of sun.

[bigmt]

We have been getting at least a bit of rain almost every day for February. So it's not like this ridge has been giving us lots of sun. We're far below what we should be for number of hours of sun.

Well the PNA domain is fairly large, much like the NAO for us in the east not every PNA pattern cuts the same way. This is one of the things about Henry which drives me nuts when he talks about the NAO as if every negative NAO is the same and will deliver a big coastal storm without really ever pointing out the different positions and strength of the block and how that factors in. The AO is another big player because without a -AO the cold air source from the far north can get shut off from dumping southwards. The PNA and NAO help to direct that cold air either into the west or east as the longwave pattern dictates. Lately we've been stuck in this -NAO and +PNA setup which favours the cold to shunt into the east.

The best setup for the west would generally be a -PDO (which we have now and should persist for years with some fluctuations) and a Nina event rather than the neutral ENSO we've had this year. Looking back at the PNA graph also shows a good deal of variability since late Dec with only two periods of strong deviation from neutral which isn't that unusual when we're lacking ENSO forcing.

This winter didn't deliver but with the negative PDO ongoing the west can be reasonably hopeful looking towards future seasons, especially if we can score a good Nina event - not like last year's garbage one, another example of how every teleconnection pattern doesn't necessarily turn out the way we would expect.

[Michael1]

So, we go an entire winter on the E. Coast of the Island with, well, no winter-BUT then, it snows last night, just enough to make my sprouting plants slushy. Then it froze- I'm now producing veg, for the freezer aisle

[stuffradio]

So, we go an entire winter on the E. Coast of the Island with, well, no winter-BUT then, it snows last night, just enough to make my sprouting plants slushy. Then it froze- I'm now producing veg, for the freezer aisle

It was snowing yesterday for me too. Oh well, no real damage done for me though. All my vegetables direct sown are hardy and small as it is.