A Cooler Week Ahead

A cooler week is in store for us as we move into the last month of meteorological winter. Temperatures don’t, however, look like they’ll be too far from normal through most of the week.

Surface Pressure Map

Surface Pressure Map – valid 12Z Tuesday, February 6, 2012

With the passage of a cold front this morning, gusty northerly winds will usher colder air into Southern Manitoba. As a result temperatures will fall throughout the day today, with midday conditions in the mid-minus single digits. There will be a few scattered flurries this morning through Southern Manitoba as the cold front works its way through the area, however there will be no significant accumulations with them. Tonight, a strong area of high pressure will build into Southern Manitoba, with the central pressure expected to be as high as 1045mb. This will bring significantly colder temperatures than we’ve enjoyed over the past week to our area overnight, with lows expected to be near -20°C in Winnipeg and as low as -25 or -26°C in some areas in the Red River Valley. Tuesday won’t be an extremely cold day as a weak warm front will push into our area from the north, but it will still be colder than we have been used to lately with highs unlikely to exceed -10C. Conditions through Wednesday will be slightly warmer, with highs expected to rise back up into the minus single digits.

Friday Morning GEMGLB Forecast Temperatures

Forecast surface temperatures from the GEM-GLB model valid 06Z Friday, February 10th with analysis. The thick black line represents the cold front.

There is some uncertainty as to how the weather will unfold later this week. Models are hinting at the potential for another push of cold air on Thursday into Friday as another cold front sweeps through the province. Models currently differ on the exact strength of the cold push, however, as shown in the image above, some models push temperatures as low as -30°C back into Southern Manitoba. Which if it comes true, we can at least take solace that we don’t live in Northern Saskatchewan, where temperatures are forecast to be as low as -45°C!

Elsewhere in Weather News

Europe Battles Cold and Snow

This past week Europe was battered with what Canadians would call a “light snowfall” where many parts of the United-Kingdom, including London, received 10cm of snow this past weekend. The European infrastructure isn’t equipped to handle a snow storm of such magnitude which was affirmed by the fact that there were widespread airport cancellations and traffic was crawling to a standstill – some drivers were even stuck in their cars on the freeways overnight. The storm also prompted the UK Met offices to issue freezing rain warnings and cold weather alerts. The snowfall was due to a warm front pushing inland off the Atlantic Ocean and clashing with colder air that was present in the region prior, thanks to another low pressure system off to the east. The snow storm that has been wreaking havoc is forecast to lift and leave the area by Tuesday morning, leaving warmer temperatures behind and clearer conditions to come.

Surface Map for the UK

System’s analysis with the warm front arriving inland, clashing with the colder air to the east (occluded front). (Source: Met Office: UK)

Cold weather also affected other parts of Europe including Ukraine and Italy, with Ukraine being one of the hardest-hit of the Eastern European countries and experiencing tragedy. Kiev, Ukraine’s capital city, normally has temperatures averaging minus five Celsius for the month of February. During this cold snap however, temperatures dipped lower than minus thirty Celsius and many people have died – over 300 as of this posting. Temperatures for the next week are forecast to remain well below average, with highs only reaching the minus teens.

Snow in Rome

City of Rome, largest snowfall in two and a half decades. (Source: Dailymail)

In Rome, Italy, the city has received its largest snowfall in two and a half decades. The city was buried in ten to twenty centimetres, leaving the city paralyzed and people freezing in their houses, since homeowners are only allowed twelve hours of heating per day (to reduce emissions). As the low pressure system plans to stick around for a couple more days, Rome will experience well below average high temperatures of about five Celsius (average of thirteen Celsius).

Surface Map of Europe

Europe’s system analysis, Feb 5th, showing both lows impacting Europe. (Source: Intellicast)

Elsewhere in Weather News has been provided by Matt

Another Warm (but Snowy?) Week

Southern Manitoba’s non-winter just keeps rolling along. Our record warm January will end just as it started – unusually mild. Although there may be an unwelcome surprise to end the month as well…

GEM Temperature forecast - Tuesday, January 31, 2012

GEM Temperature Forecast – Tuesday, January 31, 2012

The last few days of January are expected to feature high temperatures near zero degrees. Monday and Tuesday should be near to or slightly above zero in much of Southern Manitoba. Wednesday is not in January, but it is also expected to be quite warm with highs close to zero.

Surface Pressure Map - Tuesday, January 31, 2012

Surface Pressure Map – Tuesday, January 31, 2012

This warm weather may come at a cost though. During the late hours of Sunday night and early hours of Monday morning snow was falling in many parts of Southern Manitoba. Overnight accumulations were generally light, mainly 2 to 4cm or less. However, the bigger concern for snow will come Monday night and Tuesday. An Alberta Clipper type system is forecast to emerge from the Rockies on Monday. This system will then quickly dive southward on Monday night. Currently the potential for snow with this system is very uncertain. Weather models are predicting anywhere from 0cm to 15cm. As a result, it is very tricky to pin down a more precise snowfall range at this time. As a rough guideline, I will suggest that most parts of Southern Manitoba will see 3 to 6cm of snow with this system. However, bear in mind that we have low confidence in this forecast. The map above shows the expected location of the low pressure system on Tuesday morning (6am). As the exact track and intensity of this system becomes clearer we will provide further updates.

Climate Prediction Center Outlook

Climate Prediction Center Outlook – February 4-8

On a different note, long range modelling shows warm weather persisting through the first 7-10 days of February. The Climate Prediction Centre outlook, seen above, indicates that much of the United States and Southern Canada will be warmer than normal to begin the next month. Many people have been asking where winter has gone…your guess is as good as mine.

Elsewhere in Weather News

Iggy Thrashes Indonesia, Spawns Tornadoes

Tropical Cyclone Iggy has spawned over the eastern Indian Ocean and has brought with it powerful thunderstorms and tornadoes. As the rain season is peaking in Indonesia, chances of a tropical storm increase greatly and could potentially bring with it powerful tornadoes affecting the region.

Infrared Satellite image of Indonesia

Iggy bringing storms to Indonesia on January 26th. IR – cloud tops satellite picture. (Source: NASA and Earthsky).

In total, 22 Indonesian districts experienced damage from the tornadoes, several with significant devastation including Java and Bali, the hardest hit areas. Unfortunately, the tornadoes damaged more than a thousand houses, killed as many as seven people and injured fifty more as it knocked down trees and overturned boats by the shoreline.

Iggy is forecast to move to the south-east, sliding by Australia’s western coast and bringing with it heavy rains, strong winds and possibly more tornadoes. As very warm waters lie to its south-east, Iggy will also strengthen as it moves towards Australia, with the possibility of the cyclone reaching category 2 (winds of 150k/h near the core) by the time it’s all said and done.

Strong Cold Front Pushes through Dixie Alley, US

As the southern states continue to get beat down, yet another powerful system has pushed through the Dixie Alley bringing with it… yes you guessed right, more tornadic supercells! Most of the tornadoes were concentrated in the Mississippi, Arkansas and Alabama regions; where on the evening of January 22nd, optimal conditions were in place for long-tracked supercells. In total, about 30 tornadoes and more than 150 cases of high wind gusts were reported during this unusually strong system that spanned from Chicago to the Gulf of Mexico. The system then moved on to Georgia where a couple tornadoes were again reported from the same system the next morning.

RADAR image of severe storms in the Southern US

Time lapse (Sun, Jan. 22, 7pm thru 7am) RADAR imagery where rotation was detected. (Source SPC, G. Carbin)

The region finally caught a break from the parade of storm systems passing through this past weekend with a ridge of high pressure that built itself behind the front. Calm weather in the region is expected to last at least until Wednesday evening, where there is another system on the horizon.

Elsewhere in Weather News has been provided by Matt

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

Going Into the Deep Freeze

After an extraordinarily warm start to January, our weather is about to take an abrupt turn toward very cold conditions. It was only last Tuesday that temperatures were well above zero in Southern Manitoba. By the time this Tuesday rolls around, conditions will be starkly different.

Surface Pressure Map of the Prairies for Monday, Jan 16/12

Map of Surface Pressure Over the Prairies – valid Monday, January 16, 2012

The colder weather that is currently overtaking the Prairies is the result of a low pressure system that crossed the region on Sunday. As the low raced across the Prairies, it dragged down an arctic air mass in its wake. This arctic air mass will be centred around a 1040mb high pressure system, which is currently in the process of breaking away from a much larger 1063mb high over the Yukon. While in summer high pressure usually means warm and sunny conditions, in winter a large high pressure system usually means sunny but very cold weather.

Surface Temperature Map of the Prairies for Tuesday, Jan 17/12

Map of Surface Temperatures Over the Prairies – valid Tuesday, January 17, 2012

Temperatures in Southern Manitoba on Monday will be in the mid to high minus teens, which is slightly below normal for this time of year (normal high is -13C). However, by Tuesday it looks unlikely that temperatures will rise above -20C during the day. Despite the very cold high temperatures that are expected this week, overnight lows will not be that extreme in Southern Manitoba. Currently it doesn’t look like we’ll get much below -30C in most areas (save for Thursday, when we might see an extremely cold morning). Wind chill values toward -40 are entirely possible this week, especially in the morning hours when actual temperatures are still very cold. Our neighbours to the west in Alberta and Saskatchewan will be much worse off, as low temperatures in those provinces are expected to hit -40C this week.

In the longer range it appears unlikely that we will return to the very warm conditions that we experienced earlier this month. However, that doesn’t mean the rest of January will be extremely cold. We don’t yet know how long this cold spell will last, though bear in mind that arctic air is very dense and does not like to move quickly. In terms of snow, weather models are showing a return to a stormier pattern for the rest of January. It looks as though a minor weather system may give Southern Manitoba a couple centimetres of snow on Tuesday. Other than that, it doesn’t look like we’ll see any snow until next weekend at the earliest. Typically colder patterns tend to bring more snow than warmer patterns. This explains why our winter has been fairly snow-free thus far.

Elsewhere in Weather News

US Tornado Season Kicks Off Early in 2012

One of the Unites States’ first significant tornadoes of the 2012 storm season has caused quite a bit of damage in western North Carolina on January 11th 2012. What caused the tornado was a potent cold front pushing across the region coupled with just the right amount of instability and shear. This storm system was associated with a low pressure system moving up the east coast and bringing unseasonably warm and moist air to the south-east states. The EF-2 tornado (about 115mph wind speeds) caused major structural damage to at least 50 homes and knocked out power to 800 homes in the North Carolina area. Thankfully no fatalities were related to this tornado.

Tornado Damage

North Carolina Tornado Damage – Photo source WBTV news

Ironically on the back side of this low (where the high pressure dome is moving in) winter is set to arrive with gusty winds and snowfall. The tornado’s cleanup will have to be done in wintery conditions.

2012 Starts Off With Extremes in Australia and Europe

Australia’s summer has started off as a sizzler in 2012 and Europe has had record snowfalls. Both these cases are examples of how extremes have already shown up in 2012. Southern Australia has produced some extreme averages; lows of 30ºC and continuous highs of 45ºC or more (7ºC+ above average). These extremely warm temperatures are causing brushfires to spring up almost anywhere in Australia’s southern counties, keeping firefighters on the go.

Meanwhile parts of Europe have had snowfalls that have buried them in snow which has left many ski resorts, including Zugspitze summit in Germany, covered. In this location there was less than a foot of snow a couple weeks ago, however now that several powerful systems have passed, more than 6 feet of snow have accumulated there!

CO2 Values

CO2 Values Graph – Courtesy of Arctic Warming (whyflies.org)

Many scientists believe that these extremes come down to how the Arctic sea ice has diminished significantly in the last couple years and how greenhouse gas levels (CO2) have been rising to an unprecedented level. One can also assume that these extremes happen naturally and the Earth is simply going through a warm cycle, as there is no exact proof that these could be the cause – it is for you to decide!

Elsewhere in Weather News has been provided by Matt.