Welcome to the first day of astronomical spring

Today marks the spring equinox, the day when the Earth’s tilt and movement around our star positions the sun directly above our equator.  Also called astronomical spring, today’s milestone brings to mind warmer air and longer days … well, at least the second part will be true in the near term.  I’m afraid warm weather lovers are in for a bit of a shock after yesterday’s high temperature of 60 degrees, which was close to the average high. Today’s temperatures will top out in the mid-50s ahead of an upper level low that will mark the grand entrance of a very cold long wave trough into our region.

That upper level low will drag a reinforcing cold front across the I-95 corridor sometime between 9 pm and midnight tonight that will swap wind directions around to the northwest and let loose the dogs of winter once again.  The disturbance plus the very cold air will trigger some snow showers tonight that won’t accumulate but could startle those out and about after dark. Thursday will then seem much more like a mid-January day with high temperatures struggling to reach 40 degrees – and perhaps a few snow flurries – as the long wave trough settles in:

This trough will be a fixture over the ‘Burg for at least the next couple of weeks as it continues to bring cold blasts from Canada down our way.  The long term weather parameters all signal a very cold start to spring this year, with one (the Arctic Oscillation) plunging to negative values not seen for a number of years. Thus other than a day here and there that may have normal temperatures it doesn’t look like the ‘Burg will feel much like spring until sometime in April.

Also I should note that there is evidence in the models of a surface low pressure center scooting through our region Sunday into Monday.  Right now the model solutions are still jumping around a bit but there will be both moisture and cold air around so the potential for frozen precipitation is there.  I mention that only as a heads up at this point…we will have a clearer picture of that possible situation by Friday.

Happy first day of Spring!

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