North America could experience record-breaking heat this week as scorching daytime temperatures hit from south Manitoba in Canada all the way to Texas in the southern US.
A powerful ridge of high pressure has built up over the continent, with a strong southerly flow amplifying high temperatures this week as it drags up a hot, dry, air mass. Environment and Climate Change Canada and the National Weather Service in the US have both issued heat alerts across their respective countries due to how extreme the temperatures are for the time of year.
Temperatures are set to soar nearly 19C above the seasonal average in southern Manitoba, with some models suggesting daytime maxima in Winnipeg could reach 36C on Tuesday. Tropical nights – those where temperatures do not fall below 20C – are likely for the city, with the overnight lows currently forecast to stay around 21C.
Remarkably, just three days later, on Friday, daytime maxima are set to plummet nearly 30C, with daytime temperatures expected not to exceed 7C.
In Texas, the heat is forecast to peak on Wednesday, with widespread record-breaking temperatures above 40C (104F), 11-13C above the average for the time of year.
Austin, the state capital, has a climate record spanning back to 1891, of which the record high temperature in May was recorded in 1925, at 104F (40C); some forecast models are hinting that the record is likely to be broken on Tuesday and Wednesday, when temperatures could hit 108F (42.4C).
San Antonio also looks likely to smash its current record of 104F (40C). While this record was set more recently, in 2004, temperatures are forecast to extend the record by a large margin, potentially reaching 109F (43C).
Fort Worth, in the north-east of the state, could experience 106F (41C) on Wednesday too, but this would be just shy of the 1927 May record of 107F (41.6C). It will however, beat the date record for 14 May, which currently stands at 95F (35C) set in 1955.
Central and north-western Europe are unlikely to have significant rainfall this week, edging closer to widespread drought conditions after such dry and warm weather through the late winter and spring so far.
Soil moisture indices are showing that many places are currently at the “permanent wilting point”, meaning available water in the soil has been exhausted leading to plants permanently wilting. It is not only widespread at the surface, but also seeping through the deeper layers of the soil, meaning that those plants with tap-root systems and trees will begin experiencing drought stress as the deeper soil moisture reserves dwindle.
High pressure is expected to remain dominant over the next couple of weeks, blocking the arrival of frontal systems from the Atlantic that would give much-needed rainfall.
