Beautiful Week Ahead; Stormy Weekend

The Red River Valley will bask in the sunshine through the rest of the work week before a strong spring storm system moves into the area, bringing rain and snow for the weekend.

Unlike our friends to the west in Alberta, where a major winter storm is set to dump 15-25cm of snow through areas west of Highway 2 over the next two days, a ridge in place over Manitoba will keep skies clear and temperatures warm over the next few days, with plenty of sunshine and daytime highs of around 15°C and overnight lows around 2°C.

850mb Winds

850mb winds from the GEMGLB valid 06Z Saturday morning.

Our next weather system will move in this weekend, with an upper trough swinging eastwards across the Prairies. An area of rain will blossom in Saskatchewan through the day on Friday with rainfall intensifying through the day. Embedded thunderstorms may increase rainfall amounts for SK, but currently it looks like rainfall amounts of 20-40mm are possible for SE Saskatchewan, with some models painting as much as 75-85mm of rain! This system will track eastwards into Southern Manitoba through Friday night.

Southern Manitoba will be under the influence of this system through Saturday and Sunday, with some regions seeing rain changing over to snow on Sunday as cold air is wrapped into this system. Given the system’s intensity and its time out, we’ll wait to look at it in more detail on Friday when things are a bit clearer.

For now, get out there and enjoy that sunshine!

Rain on Monday, Nice Midweek

Another weak weather system is in store to start the week. A bit of rain is in the forecast for Monday, but conditions will improve rapidly toward midweek.

Surface map for Monday

HPC’s surface map for Monday showing the location of the cold front

A low pressure system and its associated cold front will generate some light rain over South-Central and Eastern Manitoba on Monday. Accumulations will generally be around 5mm in the Red River Valley and South-Eastern Manitoba. Some areas near the Ontario border may see amounts closer to 10mm. There is a small chance that some thunderstorms may become embedded within the area of rain. Any areas that experience weak thunderstorm activity may see slightly higher rainfall amounts.

Since a cold front will be passing through on Monday temperatures will be cooler than on the weekend. Highs in the Red River Valley and South-Eastern Manitoba will be around 10 degrees. Some areas will be slightly warmer or colder than that mark depending on when the rain starts and how quickly the cold front goes through.

The middle of the week is looking good. Tuesday should be a very nice day with highs in the mid teens and relatively light wind speeds. High temperatures on Wednesday should be in the high teens or near twenty degrees. On Thursday we will have a shot at twenty degrees yet again.

Low pressure system forecast to impact Southern Manitoba next weekend

Low pressure system forecast to impact Southern Manitoba next weekend – image courtesy of College of Dupage

Unfortunately, conditions are forecast to turn unsettled for the weekend. Current models show a strong low pressure system impacting Southern Manitoba on Saturday and Sunday. Should this system pan out, which is never a certainty, it could be both a rain and snow producer. It is too early to get into any further detail, but this potential storm bears watching.

March 2012 was the warmest March on record in Winnipeg since records began in 1872. The month ended up with a mean temperature of +2.2C, which is 8.3 degrees warmer than normal (-6.1C). Prior to this year Winnipeg’s warmest March on record was the March of 1878, with a mean temperature of +1.6C. Below is a recap of the many records broken last month:

  • 8 daily record high temperatures (11, 12, 15, 16, 17, 18, 19, 22)
  • Earliest 20°C reading on record (March 18)
  • Warmest overnight low in March (14°C on the night of March 18/19)
  • Earliest thunderstorm on record since 1953 (Evening of March 19th)
  • Warmest March day on record (March 19th, 23.7°C)
  • Most significant departure from normal temperature for any day of the year (+23.4°C above normal on March 19th)
  • 4 consecutive days over 19°C (Only 4 days since records began have reached that mark. From Rob’s Blog: In other words, it took only 4 days during this warm spell to match what took 140 years to accomplish.)
  • Warmest March on Record (Mean temperature of 2.2°C, beating the previous record of 1.6°C set in 1878).
  • Highest dew point in March (17°C on March 19th, need to finish parsing data set to verify)

Elsewhere in Weather News

Rare, Large Mexican Landspout Touches Down

On the outskirts of the city of Nuevo-Laredo, Mexico, located near the Texan border, an unusual sight could be seen on Thursday, March the 29th. An abnormally large landspout touched down for an extended period of time, picking up dust, trees, shrubs and flipping over a trailer on the highway. In this case, thankfully no one was injured but landspouts are often underestimated and can create as much damage as a tornado, over a smaller area.

Landspout crossing the highway on the outskirts of Nuevo-Laredo on Thursday March 29th. (Source: Melissa Estrada)

Landspout crossing the highway on the outskirts of Nuevo-Laredo on Thursday March 29th. (Source: Melissa Estrada)

The landspout is of the same family as a tornado however they have different characteristics than a tornado, which is typically spawned by a supercell. Landspouts usually spin up under towering cumulus or non-supercellular storms, as the updraft catches the rotation at ground level. This is different compared to a tornado, which starts from the base of a supercell as a funnel and proceeds to drop until it reaches the ground and becomes a tornado. The speed inside this rotating column of air (landspout) increases as the column is stretched out and can possibly become as damaging as a tornado.

The severe, elevated storm also brought with it some hail the size of tennis balls that accompanied the landspout. No other damage other than the flipped trailer was reported as the landspout moved into unpopulated areas of the Mexican plains.

Elsewhere in Weather News has been provided by Matt

Continuing Unsettled Weather

Southern Manitoba will continue to see unsettled weather through the weekend with system after system tracking through our region. Despite this, temperatures will remain above normal, contiuning this month’s summer-like trend.

We’ll start off with clear skies this morning with patchy fog through the Red River Valley which will burn off by mid-to-late morning as that late-March sun gets to work. We’ll see our temperature get up to 12 or 13°C before skies cloud over mid-to-late afternoon. Most areas in the Red River Valley, including Winnipeg, will then have a chance of seeing some showers as a weak warm front pushes eastwards through the area.

GEM-REG Precipitation for Friday Night

GEM-REG Accumulated Precipitation for Friday night.

Overnight, much of the Red River Valley has a decent chance to see rain as the mid-levels destabilize with an injection of cold air at 700mb associated with a shortwave tracking through Central Manitoba. Positioning of the shortwave will be crucial to where the precipitation falls, but current indications are that an area of rain will blossom overnight near Brandon and travel east, with lighter showers south of the Trans-Canada Highway and 4-8mm of rain along and north of the TCH.

That rain will clear out by midday Saturday, and the Red River Valley will be left with just a few clouds and beautiful temperatures around 15°C.

24-Hour Precipitation Accumulation Monday Evening to Tuesday Evening

24-Hour Precipitation Accumulation from Monday evening to Tuesday Evening

It was not mean to last, however, as yet another low begins it’s trek into the Prairies. Winnipeg will get to 11 or 12°C before more clouds push in by mid-afternoon. Light rain will push into the Red River Valley overnight Sunday and then intensify Monday morning, dropping another 5-10mm of rain before it pulls out on Monday evening.

All of these systems are sensitive to exact tracks of subtle features, so we’ll be sure to provide updates in the comments as the weekend progresses. In short, for much of the Red River Valley, the next few days will be unsettled with pleasant temperatures in the low-to-mid teens when the sun manages to poke out and showers/rain every 24-36 hours.

Unsettled March Weather Continues

Southern Manitoba played host to almost all the different kinds of weather out there, with many locations seeing almost any combination of thunderstorms, hail, rain, drizzle, snow and blowing snow. A system that brought heavy snowfall to Western Manitoba and the Interlake region as well as thunderstorms and rain to the Red River Valley and Southeast Manitoba has trundled off into Ontario; we’re not out of the woods yet, though, as another system is set to quickly make it’s way into the province by tomorrow morning.

Hail Accumulation

Photo of accumulated small hail at a downspout exit. Winnipeg was hit with hail from this size up to as large as dimes as a thunderstorm pushed through the city at around 2:30AM on Tuesday morning.

For today, we’ll see cloudy skies with a chance of a few remnant flurries this morning. We’ll see a daytime highs of only 2°C or 3°C through the RRV. Another low pressure system is already on it’s way to Manitoba, however, with the parent upper trough making landfall on the Oregon coast last night. This trough will advect eastwards and rotate northwards into the Central Prairies, bringing with it a warm front that will bisect the Prairies and slowly push eastwards.

This warm front is expected to push through the Winnipeg and the Red River Valley through the day on Thursday. Current indications are that we’ll be far enough south that we won’t have to worry about snow, that should be reserved for areas a bit further north in the Interlake region. We’ll see rain push in tomorrow morning around mid-morning and clear out by early evening. Rainfall totals currently look to be fairly uniform through the Red River Valley with totals around 10-15mm, however it does look like there’s a good chance for some enhanced convective areas which will result in fairly heavy showers interspersed through the general area of rain.We’ll enjoy warmer temperatures through the rest of the week, with the warm air pushing through bringing our daytime highs up to around 10°C.

We’re not out of the woods quite yet, though, as another low is forecast to track through the southern Interlake region bringing rain to areas along and north of the Trans-Canada Highway Friday night and Saturday morning. Current indications are that regions south of the Trans-Canada Highway will only see some scattered showers with this system.

8-14 Day Temperature Anomaly Outlook

NAEFS 8-14 Day Temperature Anomaly Outlook, valid for April 4 – April 11.

With a the passage of Tuesday’s weather system, North America has transitioned into a much different weather pattern that that which brought us our record-busting heat wave. With the blocking high collapsed over the SE United States, the summer-like heat will be contained further south in the Central and Southern Plains of the United States. Fortunately, the bitterly cold Arctic air that’s still omnipresent north of 60 will remain bottled up. So what does that mean for us? As the image above shows, ensemble forecasts are showing a moderate chance of above normal temperatures, however nothing nearly as certain as what was being predicted a couple weeks ago. The long-wave pattern has shifted to favor more frequent disturbances tracking through the Prairies, which should result in temperatures that may still be slightly above normal, but we’ll likely also see more precipitation than we had through much of March.