Unsettled, Cool Weather

We’ll see showers in the Red River Valley this morning as a low pressure system slides through the Interlake and Whiteshell regions but, unfortunately, little accumulations are expected as the more significant rain will stay north and east of the Valley. More cool days are ahead as this system reinforces the colder air over the province.

Rainfall Map

A low pressure system will track SE into Ontario today, bringing with it a large area of rain, represented in blue, and showers, represented in green, to Southern Manitoba.

A low pressure system dropping southwards from Northern Manitoba has pushed an area of showers through the Interlake overnight and will bring that rain through the Whiteshell and Sprague regions today. As pictured above, the low will track far to our NE into Ontario, leaving the Red River Valley with only disorganized instability in a strong NW flow pumping cooler air southwards on the backside of this system.

Temperatures through the RRV will stay steady today at 12-13°C as strong northwesterly winds pick up as the day progresses. Winds across the valley will pick up to 50km/h with gusts as high as 70-80km/h by late this morning and remain that way through most of the afternoon before beginning to ease this evening. A chance for showers exists through the whole RRV, and models are hinting that there may be some narrow, banded areas of precipitation that develop that could result in localized amounts of 2-4mm. Areas in the southwest RRV, such as Morden, will likely see nothing more than a passing sprinkle or two today while areas closer to the South Basin will likely see showers this morning.

We’ll see cool nights ahead, with lows near 3 or 4°C for the rest of the week. Thursday and Friday will bring us a mixed sky and highs only around 14°C.

Another system will push it’s way through the area on Friday, bringing another batch of scattered showers to the RRV. No significant amounts are expected across the Red River Valley.

Frosty to Start the Week

We’ll be in for a couple of chilly, perhaps you could even say frosty, days to start this week. Cool daytime highs and sub-zero nighttime lows are on tap.

GEM-REG 3hr. Precipitation Accumulation

Some light lake effect showers (shown in blue) are expected to develop on Monday as cold air flows over the relatively warm lakes winnipeg and manitoba.

After a rather chilly Monday morning, temperatures won’t make a dramatic recovery for the afternoon. Daytime highs on the first day of the week are expected to barely make the double digits in most areas, with highs generally in the 9-12C range expected. A breezy north wind and perhaps a couple of lake-effect showers won’t make the day any more pleasant. Tuesday night should be another cool one in Southern Manitoba. However, it appears frost will be isolated to areas around and east of the Red River Valley as some warmer air moving in from the west will keep temperatures above zero overnight in Western Manitoba. Daytime highs on Tuesday will be an improvement from Monday, though except for South-Western Manitoba where 20C values are expected, temperatures will generally remain stuck in the mid teens.

Yet another cold front will swing through overnight Tuesday into Wednesday ushering in another cool airmass to end the week. It appears high temperatures will be relegated to the teens from Wednesday through Friday. There appears to be slim odds of any significant precipitation this week, though we may at least get some measureable rain later in the week as a few strong impulses rotate through the region.

NAEFS Ensemble 8-14 day outlook

The NAEFS ensemble doesn’t give a strong indication of what type of weather we’ll see moving forward…

At this point the long range forecast looks fairly status quo. We’ll see some cooler than normal days and some warmer than normal days, but in general the pattern for the next week or two generally looks to be near normal on average. However, there will certainly be a fall feel to the air as nighttime temperatures regular drop down to the freezing mark and daytime highs stay close to the average high for mid-September of 18C.

Elsewhere in Weather News: September 15th, 2012

Pakistan Monsoon Flooding

Severe flooding occurred in Pakistan early this past week, after monsoon rains moved into the region and dropped large amounts of rain. Even though Pakistani officials had issued a flood warning for many low-lying areas such as Punjab and Sindh, many residents decided to stay put to battle out the floods in their villages.

As numerous canals and rivers overflowed their banks because of the heavy monsoon rains, many low-lying areas such as farmland, villages and roads were inundated with water. The highest rainfall report that could be found was in Rahimyar Khan where 193mm fell in 24 hours between Sunday the 9th and Monday the 10th.

Pakistan flooding

Two satellite images (visible/IR enhanced) showing the difference between no flooding and severe flooding in Pakistan. Notice the dark blues along the Indus River. (Source: NASA)

About 1,500 houses were destroyed in the process and over 100 people perished with waters rising quickly and houses collapsing from waters. The country’s army was deployed to execute search and rescue missions in the hardest hit areas, and to try to fill in the areas where water broke through the canals.

Flooding

Picture showing the flooded houses in the town of Larkana located in the region of Sindh. (Source: APP)

Estimated total losses look to be in the neighbourhood of a couple million, though it’s difficult to assess at this time as authorities are still tallying up the damages and looking for survivors. When the floodwaters recede, most likely in a couple days, the final tally from the total economic loss and death toll should be more accurate. This monsoon season does not compare to 2010 though, where numerous severe flooding events occurred and residents described that year as “the worst in living memory”. In 2010 the total structure damage that accounted for four billion in damages and the floods had a significant impact on 20 million people with around 2,000 deaths.

The monsoon rains have since moved away a couple days ago from the region of concern and crews will be able to clean up, repair villages and search for more survivors this weekend.

Mainly Seasonal With A Chance of 30°C

We’ll see fairly typical weather for this time of year across Winnipeg and the Red River Valley with a big exception being tomorrow: with southerly winds and a big upper ridge moving across the region, there’s a good chance we’ll see temperatures in the upper 20’s, perhaps even breaking 30°C on Saturday afternoon.

500mb Wind Speed

500mb wind speed from the GEM-REG for midday today depicting the upper ridge that is moving into the province.

We’ll see plenty of sunshine today as the aforementioned upper ridge begins working it’s way into our region. Temperatures will be able to climb up much higher than yesterday, where a cool air mass combined with clouds limited our temperatures. We’ll see a high near 25°C today, although it will be a bit of a climb as we dig out of a rather chilly morning.

On Saturday, the upper ridge will move across the province, bringing with it 850mb temperatures in the 17-18°C range. Winds will be out of the south, not the southwest, so we won’t see any significant downslope effect to help our temperatures out. As a result, we’ll see widespread highs near 28°C with a few locales getting as high as 29 or 30°C by the late afternoon.

A powerful cold front will dive southwards through the Red River Valley on Saturday evening which will usher cool Arctic air in from the north. 850mb temperatures will plummet to nearly 0°C for Sunday which will hold our daytime high to the mid-teens, most likely below the seasonal normal high of 18°C, under cloudy skies.

Cooler air will continue to push southwards into the beginning of next week, with 850mb temperatures dropping below 0°C on Monday and remaining over the region for much of the week. This will likely result in daytime highs in the mid-teens and overnight lows in the low single-digits for much of the week under more cloud than sun and a chance of showers on and off through the week.