Wednesday, March 21, 2012

oh so stable... (pm.21.mar.12)>

The day is ending just as it began... with hazy sunshine.  I didn't spot one single cumulus cloud today, but the visibility remains relatively poor, thanks to the haze and dust.  My high temperature was a notch cooler than expected, at 64.9F (18.3C), as the humidity hovered around 30-35% for most of the day.

Puffy cumulus clouds are the tell-tale sign of instabilty in the atmosphere... the higher they tower and the bigger they get, the more the differential between warmer air at the surface and colder air aloft.  The lack of those clouds today indicates that our air mass is very stable.  As long as the warm-up during the coming few days is proportional at the surface and aloft, things should remain quiet.  The downside to all that is that the haze, dust and other pollution could remain trapped here in the lowest layers of the atmosphere until we get a good thunderstorm to clean things up.  Instability has its benefits!

This slightly cooler than normal weather will be moderating as we approach the weekend, with temps expected to be back ABOVE normal by Saturday and Sunday.  The next upper-level disturbance is slated for late Sunday and Monday... and it is definitely getting to the point when a nice rain would be very welcome.    Will be watching for the potential as it develops...

WEDNESDAY NIGHT:
some haze... otherwise clear skies, with seasonal temps.
low: 11C (52F)

THURSDAY:
hazy sunshine.  still a bit cooler than normal.
high: 19C (67F)

THURSDAY NIGHT:
clear to partly cloudy.  milder.
morning low: 13C (55F)

FRIDAY:
hazy sunshine and a few clouds.  warmer.
high: 21C (70F)

SATURDAY:
partly to mostly sunny and pleasant.
morning low: 14C (57F)
daytime high: 22C (72F)

SUNDAY:
partly cloudy and warm, with a chance of a thunderstorm developing in the PM.
morning low: 15C (59F)
daytime high: 23C (73F)

MONDAY:
a period of showers and thunderstorms possible, otherwise both clouds and sun.
morning low: 14C (58F)
daytime high: 21C (70F)