By Meteorologist Tom Skilling
The 2013-14 cold season has taken Chicagoans on quite a ride. Now in its fifth month, the chill’s relentless nature has most in the area ready for a break. That’s why predictions of 40s Friday and the year’s first 50 by Monday, are being followed with such interest.
7 of 10 days on average have posted temp deficits since November and March 2014, which enters its 7th day Friday, is running 17-degrees below normal and 10-degrees colder than the same period a year ago.
Snowy spell in the forecast Saturday morning is to be sandwiched between 2 spells of “warming
Friday’s 40s—the warmest readings here in the nearly 2 weeks since Feb. 20—as well as a second surge of even milder air late Sunday and Monday, will be interrupted late Friday night and Saturday morning by a snow-generating disturbance. The system, scheduled to hit between the two mild spells, threatens to generate a slushy accumulation of up to an inch Saturday in at least parts of the area before winding down and giving way to mixed sunshine Saturday afternoon.
U.S. snowpack in decline over the past week with Pacific air’s arrival
A more westerly flow aloft—in place of the seemingly ceaseless northwest steering winds directly out of the arctic which have dominated so much of the current cold season—is sending milder Pacific air streaming across the Lower 48.
The warming which has occurred has been nibbling away at the snow cover draped across a large swath of the Lower 48.
While 57.3 per cent of the country was beneath a layer of snow as the week began, NOAA, the parent agency of the National Weather Service, reported Thursday that the country’s snow cover had dropped to 45.6% of the 48 contiguous states.
In Chicago, where an inch or more of snow has covered the ground for 68 consecutive days, the snowpack, which reached a depth of 14-inches on Feb. 17 has since dropped to 5-inches.
Powerful t-storms sweep Florida Thursday; tornadoes, waterspouts and damaging wind gusts reported
Severe t-storms, some of them tornadic, swept Florida Thursday.
For a time, a tornado watch was issued, but allowed to expire as powerful t-storms swept across the peninsula and out to sea. Wind gusts exceeded 60 mph in some of the heavier storms and storm chasers and authorities in portions of the Sunshine State reported brief tornado touchdowns.
NOAA’s Climate Prediction Center issues “El Nino Watch”
Warming of the equatorial Pacific waters is predicted by climate forecast models by a suite of forecast models, possibly of a full blown El Niño conditions there.
El Niños are carefully monitored because they can send powerful storms crashing into the U.S. West Coast while bathing much of the Midwest and northerns Plains in warmer than normal temp regimes during these regions’ cold season.
No two El Niños are exactly alike. Each has its own character. So while western storms and Midwest warming OFTEN accompany El Niños, particularly during cold seasons, some of these events produce very different results. As a result, the evolution of this latest El Niño will have to be monitored.