Clear, cool and Isobars/Milibars explained

Good morning Augusta.

This morning it is partly cloudy with a chance of rain, then overcast with a chance of rain. High of 61F. Winds from the East at 5 to 10 mph. Chance of rain 50%.

Tonight it will be overcast with a chance of rain. Low of 50F. Winds from the ENE at 5 to 10 mph shifting to the NNW after midnight. Chance of rain 50%.

The readings from my own weather instruments are:

The humidity is  73% with a Dew Point of 40ºF, Temp is 46.1ºF and the wind chill is 46.1ºF.

Our wind direction is North between 2.9 MPH and 5.2 MPH.  

Our Barometric pressure is  30.39 HPA 1018 and rising with a weather graphic indicating sun.

The UV rating is 0 out of 16, Sunrise is at 6:15 a.m. sunset is 6:53 PM and Moon Rise is at 9:43 p.m. EDT and the moon phase is waning gibbous.

For the pilots out there raw metar is:

METAR KAUG 131053Z AUTO 35005KT 10SM CLR 06/04 A3034 RMK AO2 SLP276 T00610044

Visibility is 10.0 miles/16.1 Kilometers with clear skies.

We received no rain here over the past 24 hours.

As the weather continues to change with the seasonal changes, you'll be hearing more about Isobar and Millibar measurements. So, what exactly do those terms mean?

Millibar:

n. Abbr. mb

A unit of atmospheric pressure equal to one thousandth (10-3) of a bar. Standard atmospheric pressure at sea level is about 1,013 millibars.

(The American Heritage® Dictionary of the English Language, Fourth Edition copyright ©2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved)

And:

(Mathematics & Measurements / Units) a cgs unit of atmospheric pressure equal to 10-3 bar, 100 newtons per square metre or 0.7500617 millimetre of mercury

(Collins English Dictionary – Complete and Unabridged © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003)

 

Isobar: N.

a line drawn on a weather map or chart that connects points at which the barometric pressure is the same.

(Random House Unabridged Dictionary)

And:

Isobar N.

(meteorology)an isogram connecting points having equal barometric pressure at a given time