An Arctic Blast

This week will feature the coldest weather so far this winter, which is probably about all you need to know.

850mb temperatures on Monday morning

As we come off Monday morning’s very cold low temperatures, daytime highs won’t be able to get very warm, with values in the mid minus twenties expected. When you factor in the wind chill it will feel more like the low minus forties on Monday morning and the mid minus thirties on Monday afternoon. As we move into Monday night temperatures are expected to plummet once again. Models have had significant difficulties figuring out what will happen by Tuesday morning. Models have shown lows as cold as -47C on Tuesday morning (obviously an erroneous value), or as warm as -28C. It seems probable that we’ll end up somewhere between those two extremes, with lows in the mid minus thirties most likely. It shouldn’t be very windy at all on Tuesday morning, so at least we won’t have a big wind chill to contend with as well. It looks like we’ll “warm” up a bit on Tuesday, with daytime highs in the low minus twenties expected.

We shouldn’t see extreme overnight lows again on Wednesday morning since a weak passing weather system will prevent temperatures from bottoming out. However, another arctic front is forecast to pass through Southern Manitoba during the day on Wednesday, setting up more very cold weather for late week.

Unfortunately, there are no indications to suggest that we’ll see a warm-up any time soon. That means we may be stuck with cold to very cold weather for the rest of January.

Elsewhere in Weather News: August 18th, 2012

A Look Worldwide into July, 2012

As reported on Friday, Winnipeg is shaping up to be one of the hottest years since record-keeping began 139 years ago, with July closing out as the 5th hottest month on record for the city. Wondering how the rest of the world faired this past month?

Interestingly, most of the Northern Hemisphere has also experienced extreme temperature anomalies this year. According to the National Climactic Data Center (NCDC), the Northern Hemisphere land surface temperatures this July were 1.19°C above the average, making July 2012 the warmest July in the Northern Hemisphere ever. This year has experienced no shortage of record breaking temps in the Northern Hemisphere – it is now the fourth month in a row that surface land temperature records in this hemisphere have been broken. Canada and the United States have contributed greatly to the record-shattering numbers these past four months but the heat wasn’t confined to North America. South-Eastern Europe has seen conditions almost identical to ours this summer – very dry with record-setting warmth; while Serbia and Bulgaria have been impacted with severe drought this growing season, resulting in severe crop losses. Bulgaria has lost around 10% of its wheat crops due to the sizzling heat, and their maize crops have decimated to the point whereby getting half their average crop will have to suffice. The only countries in the world to have shown significant temperatures below normal this July were Australia, Argentina and parts of the Antarctic.

Temperature anomalies July 2012

July temperature anomalies and circled, areas talked about in EIWN. (Source: NASA Earth Observatory)

Precipitation anomalies July 2012

Precipitation anomalies for July 2012 and circled in red is where severe drought is occurring in South-Eastern Europe. (Source: NCDC)

Arctic Melting

In some areas of the Arctic, July temperatures have exceeded 6°C above average. Arctic ice is continuing to melt at a disturbing rate. The expanse of the Arctic sea’s ice coverage is now at its lowest ever at this time of the year, having dropped even further than measurements from the record-setting year, 2007. In July, almost all of Greenland’s entire ice sheet experienced melting – a “rare event” as described by the National Snow & Ice Data Center (NSIDC). To put things into perspective, sea ice used to reach seven million square kilometers in the 1990s at their minimum, while it has only surpassed five million square kilometers once in the past six years (showing a 29% decrease of minimum sea ice extent in the last few decades). This has lead scientists, like Walt Meier, a scientist at NSIDC, to believe that sea ice could potentially be eliminated by the year 2030 if melting continues at this pace. If this does happen, the ice melt could trigger a domino effect: raising ocean levels, releasing methane from frozen soils, and so on.

Sea ice extent graph

Sea ice extent by year. (Source: NSIDC)

Arctic Sea Ice Extent at Record Low for 2nd Consecutive Month

Arctic Sea Ice Extent at Record Low for 2nd Consecutive Month