What Happened To Winter?

Winnipeg has been enjoy a wonderful winter, quite a surprise given that a lot of forecasts had called for colder than normal temperatures, a common occurance when La Nina is in full swing. This winter has been stellar so far, but just how warm has it been? Lets take a closer look, and then a special announcement!

For full disclosure, I’m using numbers from January 1981 to now from the Winnipeg Richardson Int’l Airport (1981-2007) and the Winnipeg Richardson AWOS (2007-Current). The numbers are gathered from the daily summary provided on the Weather Office Climate Archive site. The data used is “current” to January 25, 2012.

Looking first at daytime highs. We know that December was well above normal, as was the start to January. How much above normal?

December 2011 Temperatures vs. Climatology

December 2011 daytime highs compared to 30 year means. Maximum and minimum extrema included (these are the warmest and coolest daytime highs for those days in the last 30 years).

We can see that this year (yellow bold line), much of December was spent above our average daytime high. In fact, 84% of the days in December had daytime highs above normal, with a streak of 17 days with above normal temperatures. We were, on the days we were above normal, on average 10°C above our normal daytime highs for each respective day in December.

January 2012 Temperatures vs. Climatology

January 2012 daytime highs compared to 30 year means. Maximum and minimum extrema included (these are the warmest and coolest daytime highs for those days in the last 30 years).

So far this January, we’ve been off to a great start as well, with 71% of our days above normal for daytime highs, which isn’t bad for having quite a cold snap in the middle of the month. We had a nice streak at the beginning of the month with 11 days in a row with above normal temperatures. On the days this month that we’ve been above our normal temperatures, we’ve been, on average, 6.5°C above normal for each respective day in January.

So the days have been warm. This only tells half the story, however. An interesting story emerges when we look at overnight lows…

December 2011 Temperatures vs. Climatology

December 2011 overnight lows compared to 30 year means. Maximum and minimum extrema included (these are the warmest and coolest overnight lows for those days in the last 30 years).

When we look at December of this winter, we see a compelling argument unfold. 23 nights (74%) of the monthhad temperatures, on average, 8.4°C above normal. We had 11 nights in a row with overnight lows above normal by as much as 13.5°C! And January is an equally compelling story…

January 2012 Temperatures vs. Climatology

January 2012 overnight lows compared to 30 year means. Maximum and minimum extrema included (these are the warmest and coolest overnight lows for those days in the last 30 years).

This month, we’ve spent 16 nights with above normal temperatures (65% of the month), which have been 10.6°C above normal on average. We had a wondeful streak of 11 nights at the beginning of the month with above normal overnight lows, including January 9th, whose overnight low was a whopping 17.5°C above the 30-year mean.

So not only have we been nowhere close to as cold as it can be, we haven’t even really spent any signifigant time being anywhere near as cold as we ought to be! But there’s one way to make this even more succinct…

December 2011 Means vs. Climatology

December 2011 mean temperatures compared to 30 year means.

What I’ve done here is a crude approximation of the mean daily temperature. While it would be nice to properly integrate the hourly observations to calculate a true time-weighted mean temperature for each day, I have weather stripping to install, shelves to build, and many other things that would also like my time. So I’ve done a quick average of each day’s maximum and minimum temperatures ( [Max + Min]/2 ). I’ve calculated the 30 year mean by taking the mean of the mean daily temperatures.

What this shows us is a “combined” look at how much warmer the entire day was, instead of singular values. We can see that once we shifted into a warmer patter around the 10th of December, we cruised without looking back. A total of 26 days (84% of the month) above the normal mean daily temperature, with many days as high as 10-15°C above normal. We had 17 days in a row with above normal temperatures in December, and for all the days above normal, we were on average 6.9°C warmer.

December 2011 Means vs. Climatology

January 2012 mean temperatures compared to 30 year means.

January tells a similar story with 17 days so far above normal, on average by 10°C! What these mean values tell us is that not only have our days been warm this winter, but the entire 24-hour cycle has been significantly wamer than normal as well. Save for one day, we were above normal in hour temperatures from December 10th to January 11th, 32 days in a row. We spent a month with temperatures 6-10°C above normal on average, with many days near or warmer than 0°C during a time of the year when it’s not uncommon to be hiding inside while it’s -35°C outside! What a winter indeed!

And with ensembles predicting above normal temperatures into the middle of February, our odds of getting an entrenched arctic deep freeze in Winnipeg are starting to look mighty, mighty slim. Something I’m sure not too many people will complain about.

And Now For Something Different…

So, what if you want to make your own temperature forecast? Or precipitation forecast? What if you need to make your own decision on whether or not you should take your sailboat out on the South Basin tomorrow?

Fortunately for the public, most government agencies make their model data freely available for use. Getting at it can be difficult and time-consuming though. Everybody has their own tools for viewing data; often they are bulky and slow server-side PHP solutions. That jargon means that it’s not very fast and you spend a lot of time waiting for pages to reload.

Well, it doesn’t have to be that way! A Weather Moment is excited to introduce our model viewer! We’ve built a comprehensive tool that lets you view model data from several models, including Environment Canada’s GEM-Regional and GEM-Global models, the NWS NAM and GFS models, as well as the UKMET model and ECMWF. Over time, we plan on adding more publically accessible data to the viewer.

A Weather Moment Presents the Model Viewer

A Weather Moment Presents the Model Viewer!

You can easily switch models and load new products without ever having to refresh the page. We have convenient keyboard shortcuts to control everything from animation to mangification to removing frames from the loop or jumping back to the beginning or end. Our Frame Omitter gives you the control to view exactly the images you want. All of this is part of a lightning-fast backbone that lets you view model data quicker than anywhere else on the internet.

We are providing this to let you begin to see what goes into making a forecast. Please note that model data is not the “answer” to the weather. It is a computer’s opinion, and is wrong just as often as anyone else is. It can be very helpful guidance, and can often give you a good idea of what to expect.

We hope that this tool can help anybody who views our site access weather forecasting information quickly and easily! The only limitation is that, unfortunately, the viewer does not currently support Internet Explorer. There are a lot of technical reasons for this, but ultimately it’s because I’ve coded the tool to W3C standards for optimal compatibility, and Internet Explorer does not yet conform to those standards. The tool may or may not render and/or operate correctly on any version of Internet Explorer. Any other browser will work great, though (e.g. Mozilla Firefox, Google Chrome, Apple’s Safari). You can check it out by hitting the Model Viewer link at the top menu of the site, so go check it out!

A Mixed Bag On The Way

Today will bring warm temperatures along with a bit of light rain or snow as a Pacific system tracks through the Interlake towards Hudson Bay. Temperatures will climb above 0°C today before they gradually cool down by the end of the week to more seasonal values.

Probability of Snowfall >= 2cm

Probability of 12 hour snowfall accumulation exceeding 2cm, valid overnight Wednesday into Thursday morning.

A low pressure system tracking across the extreme Southern Prairies will arc northwards through Southern Manitoba today, lifting northwards through the Interlake region then exiting towards Hudson Bay. This system will intensify as it pushes into Manitoba and precipitation should blossom as it approaches the RRV. Two challenges exist with this system:

  1. When exactly will the precipitation develop/intensify?
  2. How far north with the system be?
  3. What will the phase of the precipitation be, snow or rain?

We’ll likely see some precipitation early this afternoon in the form of snow as the warm front pushes through the RRV. The Western RRV has a risk of some freezing rain if temperatures can stay below 0°C for long enough with this batch of precipitation. Any freezing rain that does develop will be short-lived, though. The snow will likely stop for the short period we’re in the warm sector of this system, but will return by late-afternoon/early evening with some rain or wet snow as the cold front passes through the area. The precipitation will end later in the evening. Snowfall accumulations today should be quite low in the RRV given the warm temperatures, however areas further east in the Whiteshell have a decent chance of getting around 2cm.

Temperatures should reach the 3-4°C range through most areas south of the Trans-Canada Highway today and drop only a little below 0°C overnight.

For Thursday, temperatures will reach close to 0°C as an elongated trough moves across the RRV, bringing with it a slight chance of flurries. It should pass by lunch, after which the NW winds will bring in cooler air and drop the temperature slowly through the afternoon.

The rest of the week will be relatively quiet, with temperatures gradually returning to more seasonal values (daytime highs moving from the low minus single digits to the high minus teens). The next chance for significant weather looks to be early next week.

Since it will likely be quiet on the weekend, I plan on having a bit of a special post on Friday! We’ll look at how warm this winter has actually been, and I’ll be unveiling a great new tool (barring no more problems…) that I’m really excited to let everybody get their hands on!

Much Nicer This Week

Temperatures this week will be a big improvement over last week. By mid-week we might even take a run at the zero mark.

GEM-GLB Temperatures on Wednesday, January 25, 2012

High temperature forecast for Wednesday, January 25, 2012 – areas south of black line are forecast to be 0°C or warmer

Temperatures through the first few days of the week are expected to be around or above normal (normal high being -13°C). Monday will be around normal, with highs in the mid minus teens in Southern Manitoba. However, Tuesday and Wednesday will be much warmer. Highs on Tuesday will likely break into the minus single digits in most areas, while highs on Wednesday will be near the zero mark. The GEM model is showing high temperatures reaching (or exceeding) the zero mark on Wednesday in much of Southern Manitoba. The GFS model likewise shows highs around zero on Wednesday. After a really warm Wednesday, the last two days of the work-week will be cooler.

The warmer weather is a result of upper-level ridging building into the Western Prairies, which will return our milder, west-to-southwest flow through the upper atmosphere, instead of the cold northwest-to-northerly flow we’ve been influenced by over the past week.

Our next chance for snow will likely come with the same system that will bring us the warm temperatures this week. A frontal boundary will sweep the warm air from Southern Manitoba later on Wednesday and may generate some snow in its wake. If we do see snow under this scenario, amounts will generally be light…but blowing snow could be an issue as the cold front is expected to usher in gusty north-west winds.

NAEFS Long-range Prediction

NAEFS Long-range prediction – January 19 to February 5

In the longer range I don’t see an immediate return to extremely cold weather. On the other hand, don’t expect early January type warmth either. Most indications suggest that we’ll end January with weather that is right around normal. The ensemble model, as shown above, gives a good indication of what type of weather to expect in the longer range. For most of the winter it has done a pretty good job in providing advance warning when major warm-ups or cool-downs are coming. Right now it doesn’t show much of anything, a sign that we’re likely to cruise into February without any highly abnormal weather.

Elsewhere in Weather News

Large Low Hits US Northwest

This past week a major snowstorm took hold of the US northwest, bringing a mixed bag of precipitation across the region. Various parts of Washington State were paralyzed, especially the west coast, by freezing rain initially (Wednesday/Thursday). The freezing rain brought down power lines and left about 200,000 people in the dark. It also wrecked havoc on the roads, forcing the state to shut down a couple major interstates and prompting Governor Gregoire to issue a state of emergency.

Weather Warnings across the northwest US

US Northwest littered with snowfall, freezing rain, and flood warnings. (Source: US National Weather Service)

Following the freezing rain, the storm brought heavy snow where totals topped 15cm in many locations across the Northwest. Here’s a short list of some of the higher snow accumulations throughout the region (Monday-Thursday):

  • 127cm – Mount Hood Meadows, OR
  • 60cm – Covington Mills, CA
  • 18cm – Seattle, WA

Many locations in Oregon and California also received significant rainfall with this low as well as strong wind gusts. A complete storm summary, made available by NCEP is available here.

Moisture arriving along the western coast of the US

Atmospheric river arriving inland on the US Northwest coast. (Source: SPC)

This unusually strong system resulted from a large amount of moisture being drawn with south-west winds from as far south as Hawaii. The so called “atmospheric river” then flows inland, in this case in Northwest US, and subsequently drops large amounts of precipitation.

Tropical Storm Funso Spins Up

Satellite image of tropical storm Funso

Cyclonic storm between Mozambique coast and Madagascar January 22. (Source: Meteosat 7; CIMSS)

A strong tropical storm has spun up on Mozambique’s east coast (African coast) in the last couple days. The storm is located in the Mozambique Channel and is predicted to intensify with the formation of a cyclonic eye. The warm sea surface temperatures (SST’s) and moist air trapped in the channel are contributing largely to the strengthening of the cyclone. It is expected to evolve into a strong cyclonic storm by Monday afternoon after the main center of the storm moves back over water. The main worries with this cyclone are the strong winds associated with it and flooding due to the slow moving nature of the storm. Mozambique’s coast will be affected significantly before the storm gets steered towards the south-west later in the week.

Elsewhere in Weather News has been provided by Matt

The End of The Arctic Deep Freeze

After a couple days of bitterly cold temperatures, the end is already in sight for Southern Manitoba. Perhaps we shouldn’t complain, though, as Southern Manitoba got off pretty easy compared to the rest of Prairies, where temperatures plummeted to nearly -40°C through most areas, let alone considering the wind chill on top of that.

Pacific Analysis of Incoming System

Analysis of the Eastern Pacific, Jan. 12, 2012 02:45Z. A powerful low pressure system situated approximately 1000km off the British Columbia coast will bring a significant change to our weather pattern.

A powerful system pushing towards B.C. will bring a significant change to our weather pattern this weekend. As this system pushes into the western portions of the continent, the Arctic Vortex, currently situated near Baker Lake, NU, that has been pushing extremely cold air over the Prairies will begin to collapse and retrograde back towards the Gulf of Alaska.

As this happens, the large-scale flow over the Prairies will shift from northwest to southwest, and what a difference 60 degrees can make.

Temperatures will begin to rise on Saturday, as the arctic air begins to be pushed back northwards, and most areas in Southern Manitoba should see temperatures rise to around -12°C. Temperatures will continue to rise overnight and through Sunday up to around -5°C over the RRV as the actual low approaches.

We’ll likely see a couple of cm of light snow Friday night through Saturday as the warm front slowly lifts from North Dakota into the Interlake region. Past that, it gets a little tricky, as some models are forecasting substantial snowfall through Sunday while others keep all snowfall well north of the Trans-Canada Highway. Best case scenarios bring only light snow to the RRV on Sunday night in the wrap around for this system, while more pessimistic approaches bring close to 10cm of snow to our area through light-to-moderate snow through Sunday and Sunday night. It should start to become a little clearer over the next day or two, as the low approaches the coast. Currently, ensemble models predict that we’ll see little snow, and that accumulations should occur through the Interlake, and not as far south as Winnipeg.

After Sunday, we’ll cool back down to seasonal to slightly-above seasonal temperatures through much of next week, with daytime highs generally between -15°C and -10°C. All in all, next week looks quite pleasant. We’ll be sure to provide updates in the comments on how much snow we can expect for Sunday through the coming days!