Tuesday, January 31, 2012

Updated map etc.

Dusting overnight and currently snowing in Ottawa.   I think it'll snow for another few hours off and on with flurries afterward.   It may pick up again overnight tonight but most of the precip will stay to the north.

A/W updated its snowmap:

Monday, January 30, 2012

A/W's two bits

The models are still printing out only a 1/4 of precipitation (liquid equivalent) over the next 48 hrs.  Given this snow is developing along a pushing warm front, snow ratios will not be high.  Even at a conservative 10:1 ratio, that'll give only about 6 cms of snow at most.

Here the contribution from A/W:


This week and February

First off, EC is too high on a couple things this week. 
-  The snow for tonight/tomorrow.   I'm thinking 2-5 cms rather than 5-10cm with a dusting tonight and a couple cms tomorrow.  (TWN agrees with me)
-  The temperature on Wednesday will not get to +7C.   It may pop above 0C briefly, definitely not by more than 1 or 2 degrees.  (TWN does not agree with me with a +5C forecast high)  AfterWednesday, temps should be heading down towards more normal levels.

For the month of February, especially the middle two weeks, it looks to be at or below temperatures with some good opportunities for a decent storm. 

Friday, January 27, 2012

Posting from the train....

Just to say that there will be no further posts until Monday.

Just want to note that it didn't get above 0C today.  But that didn't stop the ice rain from coming.  Rats.

Thursday, January 26, 2012

Latest EC forecast

11 AM release moves more towards my thinking but still too much non-snow precip.:

Tonight: Cloudy. Snow mixed with ice pellets beginning early this evening then changing to freezing rain at times mixed with ice pellets overnight. Snow and ice pellet amount 2 to 4 cm. Wind becoming east 20 km/h after midnight. Low minus 6 with temperature rising to minus 2 by morning.

 

Friday: Freezing rain at times mixed with ice pellets changing to snow mixed with ice pellets in the morning and ending early in the evening then partly cloudy with 60 percent chance of flurries. Snow and ice pellet amount 2 cm. Wind east 20 km/h becoming west 30 gusting to 50 early in the afternoon. High plus 1.

 

Saturday: Flurries. Low minus 5. High zero.

All together now...

Generally speaking the models have aligned themselves to the mean track and timing from a couple days ago, that is south of Lake Erie and Ontario over central PA and NY states Thursday night into Friday.  Now the argument is about intensity.  Again, the Canadian and the Euro are bosom buddies with a fairly intense storm that puts out a fair amount of precipitation.  However, the Euro has more snow (10-15cms) than rain, a scenario I prefer (hope for).   The GFS and NAM are less intense with less precip.  These are the models I trust more so I am torn...

But the upshot is that it's going to be a bit messy tonight into tomorrow morning.  Again, I think the Canadian is underestimating the low level cold.  Therefore I doubt it's going to get up to +3C tomorrow per the latest EC forecast for Ottawa.

Wednesday, January 25, 2012

Friday into the weekend

It has been interesting to watch the models converge...somewhat.   Even 48 hours out there is still a few hundred miles of variance between the various models' solution.  For example, the Canadian and Euro have the storm center passing just south, almost over the lower Great Lakes, Erie and Ontario.  The NAM and GFS have the center passing well south of the lake and taking it to the east coast.

So what I think is going to happen is this:
- the storm will pass south of the lakes Thursday night, over central PA and NY.  It will give eastern Ontario a few cms of snow.
- the may be another dusting Saturday afternoon as a very weak clipper slides through.
- then again on Sunday as a weak cold front comes through.
- I am a little puzzled by the forecasted temperatures.   I find it hard to believe that it will be at or above zero for Friday and Sat.  I think they are underestimating the low level cold air and that it'll stay below zero on Friday and Saturday.  I am more certain about Saturday than Friday.

Global Temp snapshot

Lest any of you think our recent warm temperatures are a global phenomenon (click to embiggen):

Tuesday, January 24, 2012

Model mayhem meeting in the middle?

Interesting. 
The Euro model has come on board with the storm with the worst hitting the US NE but giving us 5 - 10cms of snow.
The JMA model has backed off on its predicted blizzard for us and is in the Euro camp right now.
The Canadian model is an outlier on one side with a storm coming right through the Great Lakes giving us another rain storm similar to the one we just had.  So EC's forecast for Friday remains unchanged.
The GFS model is also an outlier on the other side with a very weak system that scoots south of us and doesn't give us much of anything.
The NAM model is outputing is 18Z run as I type.  It is looking like the GFS but giving us a few cms of snow.
I don't have the latest UKMet.

So if you take the model mean, it'll mean a few cms for us and more for the US NE.

Likely nothing...

This morning the Canadian and JMA were joined by the UKMet in predicting a storm Friday (Sat for the JMA). So are they the three amigos or the three stooges? I am leaning towards the latter. The more reliable models, the GFS, NAM and Euro have the storm weaker, further east or offshore.
The current EC forecast for this weekend:

Friday: Snow or rain. Low minus 5. High plus 2.
Saturday: A mix of sun and cloud. Low minus 4. High zero.

I think it'll be cooler with less precip.

I will post again this afternoon after the next model runs come in.

Monday, January 23, 2012

Something out of nothing?

I've been telling people that I haven't been seeing much of anything on the models.  All of the sudden on both the latest runs of the Can and Jap. models there is a storm this coming weekend.  The japanese model espcially phases a storm and really blows it up such that if it were true, it'd be a blizzard.  Finger's crossed. :)  Unfortunately, I don't trust the Canadian and Japanese models very much in general...But ya never know.  A blind squirrel finds a nut every now and again.   That being said, the GFS and Euro are showing no such beast.

Longer term, the first part of February is looking like we'll have normal to below normal temperatures.   So I think Winterlude won't be in any danger from melting.

Today, Monday Jan 23

I notice that EC has freezing rain warning out.   While I agree that some may fall, it won't be much as mild air will overwhelm the low level cold air and turn to straight rain.   However, the solid surfaces may take a little longer to warmup and may be a little slick at first.

Friday, January 20, 2012

Antarctic

Remember when AGW was supposed to be melting the Antarctic and we were all going to drown from the rising sea levels.   Well, nevermind.

Thursday, January 19, 2012

This weekend and early next week.

I wanted to wait for the latest Euro to come out before posting this.

A clipper will coming through today this afternoon and evening giving us a few cms.  I think Saturday will be cooler than EC is currently saying (Low minus 13. High minus 9.) but we will be warming up on Sunday through Monday.   Monday will be a messy day, mild and rainy, a good day to get rid of the ice build up on your driveway.   It will be cooler the remainder of the week.

For the lower Mainland in BC, I think you're getting a bunch more snow in the coming week.

Speaking of Alaskan temperatures...

What do you think is the primary driver of Alaskan temperatures?   Hint:  it ain't CO2.

Tuesday, January 17, 2012

Glaciers in the news

Glaciers have been in the news again (with crossposts to various social media groups) with the release of a time lapse video of the Columbia Glacier in Alaska with the inevitable alarm with what Global Warming is doing to the glaciers.

Total BS, pardon my french, on two fronts.

First is the full recorded history of the glacier, which with photographic evidence has retreated for hundreds of years, far before the onset of so-called AGW.  WUWT has good smack down of this here.

Second is the temperature record of the area.  For this purpose I have selected Anchorage as the representative station from NASA's GISTEMP dataset, hardly a skeptic organization.   I also selected the primary melt season: June thru August. Below is the graph of the summer temperatures at Anchorage.  There is no trend.

Then there's the glaciers in the Washington/Oregon regions of the US.   Read this and this for details.

Forecasting this storm

While not unique in occurance, this storm has its challenges:
- It's riding along a front, i.e. very mild air on one side, very cold air on the other
- It's moving quickly
- It's intensifying as it approaches, i.e. larger, stronger winds, higher degree on mixing of the boundry layers.

As a result there is a relatively high degree of uncertainty of the storm center track, north of which will get more snow than rain and south of which will get more rain than snow.

Fun.

Monday, January 16, 2012

Cold and snow...

Much colder air was around.  Interesting article about it here.  Even Kemptville got down to about -27C.

Regarding Tuesday's system.   Unfortunately the models have trended back.   So my call is that we will start with a few cms of snow overnight with a likely change over to freezing rain or ice pellets in the morning.  Then a change over back to snow later in the day with a few more cms of accumulation.   Here is Env. Can. SWS:
A low pressure system over Northern Missouri is slowly deepening as
it tracks northeastwards towards the Lower Great Lakes. It is
expected to cross Southern Ontario into Southern Quebec on Tuesday.
This low will be moving along a front dividing mild and fairly moist
air to the south and much colder Arctic air in place over Northern
Ontario. Computer models are generally in agreement that the low
should race from lower Michigan to the southern tip of Lake Huron to
around Barrie then Ottawa on Tuesday. The current cold air over much
of southern and portions of Eastern Ontario will gradually be
Flushed out of the region through tonight before the precipitation
arrives. This will result in primarily rain across Southwestern
Ontario through Niagara and to the north of Lake Ontario.
 
Significant amounts of snow are likely from the Bruce Peninsula to
the east of Georgian Bay into Eastern Ontario to the northwest of
National Capital Region, beginning early Tuesday. Total snowfall
amounts of 10 to locally 15 centimetres are likely. The quick speed
of the low would preclude any significantly higher amounts. A
Warning has not been issued since the amounts are expected to be
Less than the warning criteria of 15 cm in 12 hours. Some
Significant freezing rain is also likely on Tuesday in a swath from
the Grey-Bruce region through Muskoka and Bancroft to near Ottawa.
Freezing rain warnings may be issued.
 
Travellers should be prepared for hazardous winter driving
Conditions Tuesday, in areas north of the track of the low. The snow
will taper off Tuesday night.
 
Environment Canada is closely monitoring this situation. Watches and
warnings may be issued as required.
 
Please monitor the latest forecasts and warnings from Environment
Canada at WWW.WEATHEROFFICE.GC.CA
Longer term, it looks like we are going to be warmer than normal for a few days next week with a return to cold at the end of the month.

Sunday, January 15, 2012

Saturday, January 14, 2012

Cold bust

9:00 PM and it's already -21C... I think we're going to get colder than the current EC forecast of -23 and TWN forecast of -24C

Tuesday's storm

Brief post:  The models have trended south and colder for the storm on Tuesday.

Friday, January 13, 2012

Storm next week...

By the looks of the radar, the snow should taper off in the Ottawa area in the next hour or so in the northwest to southeast direction as the cold front comes through.  Petawawa temperatures have fallen 5 degrees in the last two hours.    I guessimate we've gotten 10-12 cms of snow today, together with the 5 or so cms yesterday, that puts it right in the middle of the10-20 cm forecast, no?

Models are still showing colder numbers (well into the -20s C)for Sunday morning than official forecasts.  TWN is still the closest to the models with a -24C forecast low.  
(3:37PM update, EC latest forecast: -22C)

The models are also showing a storm developing along another cold front and coming through the Great Lakes region Tuesday into Wednesday.   There is some debate with respect to the timing and track.  The Canadian and Euro have it going over the central Great Lakes which has Ottawa getting a freezing rain, rain, snow storm,   The GFS has is going over the lower Lakes which would give us a mostly snow.   Right now, my gut is saying the GFS is more right as it seems to have a better grasp on the cold air push... but that may be just wishful thinking.

Thursday, January 12, 2012

Snow's back on the menu boys!

Env. Can up-ed it's snow totals again.   However they have backed off on the Sunday morning low temps.   Now they're saying -20C.  TWN is still saying -25C and Accuweather -17C (???).   However the raw model output from the NAM, GFS, EURO, and CMC has Ottawa below -27C Sunday morning.  

Storm and cold

I must confess the change over to ice pellets/rain this morning has caught me (and everybody) by surprise. I still expect a significant snow event tonight into tomorrow but today might be a wash.   I will keep an eye on it.

An update with regards to the forecast cold on Sunday morning
Env. Can. current forecast -22C
TWN forcast - 25C
Accuweather:  -17C

Wednesday, January 11, 2012

Interesting tidbit of info about the weekend cold

Even Env. Can. is not believing their own model.   Just for kicks, I checked out the Canadian model raw temps for Sunday morning and they have Ottawa well into the -20s C.  See map below.   So why is their official forecast for Sunday morning still -17C?   Well, without asking them personally, I've read that it is because they take into account the climatology, ie the "normal" temperatures for a particular place and date.   If a model output is too many standard deviations from the "normal", they adjust temperatures back closer to normal.  And what do you know, the "normal" low temperature for Ottawa is -17C.

TWN forecast low for Sunday morning is currently -19C
Accuweather forecast low for Sunday morning:  -19C
Raw GFS and Euro temps for Sunday morning:  between -25 and -30C

Western Canada and snow

Much of BC and Alberta is going to be much colder than normal for much of next week.   Colder than current Env. Can. forecasts for sure.  The map below is the 7 day mean of temperature deviations in Farhenheit ending next Thursday.

No change for snow totals for Thursday/Friday.  It's still looking like a 10-20cm storm.
Updated snowmap below (note it does not include the loads of Lake Effect Snow coming Friday/Saturday)

Tuesday, January 10, 2012

The weekend's cold

EC forecast low for Sunday morning:  -17C
TWN forecast low for Sunday morning:  -18C
Accuweather forecast for Sunday morning:  -21C

Raw GFS output: well into the -25C to -30C area.   Let's see who changes. 

10 degree bust

Note that Env. Can. forecast for Thursday's high temp is now -5C.  You'll remember that yesterday morning their forecast high for Thursday was +5C.   A ten degree difference in 24hrs.    Yes that is how bad the Canadian Model is.

Petewawa has dropped 4 degrees in the last 3hrs.   So Ottawa will start dropping soon too.

Snow totals for Thursday and Friday still look okay but they may trend toward the low end of my estimate as the NAM model is not showing as much precip as before.

Addendum:   Look for low temps in the -20s over the weekend

Monday, January 9, 2012

The week and beyond

First, I believe that Environment is likely out to lunch with the storm Thursday/Friday.   Their current predicted high of 5C on Thursday is too high.   And therefore their predicted rain/snow mix will likely be more snow that rain.   This should be a healthy storm giving us 10 - 20cm (my current estimate).
Update: EC afternoon forecast has now a high of zero for Thursday.

However, this storm is not the main story.   As intimated by my post last week Tuesday, there is major cold coming down that pipe that has staying power.   There will be a little bit of back and forth temps, but unlike the winter so far, there will be more cold than warm.   Let me show you one pic of the temperatures predicted a couple weeks from now.   While the exact temps may not be correct, it definitely shows the tone for the next few weeks.

Friday, January 6, 2012

Took a peek

The storm next week is still there late next week on both the Euro and GFS.   I'm trying hard not to jinx it.

In the short term, we not going to get much of anything, just up and down temps.

Wednesday, January 4, 2012

Tuesday, January 3, 2012

Jabs of cold until the knock out punch?

Looking at the weather pattern and trends in the modeling, the middle of the month is getting set up to be a major flip in the pattern we are in.   About that time a ridge is predicted to set up over Alaska and the polar vortex is predicted over Baffin Island (see below).  If this comes true, this will send major cold cross polar air down the plains which will spread east.   The NAO and AO are also trending towards negative territory around that time.   Again, if true, this will set up a very cold and wintery pattern for much of North America.   Until then, it looks like we'll be in a back and forth pattern with no major snows on the horizon.