Bob Breck's Blog: Temperature-Dew Point Spread Tells us The Story.

During my broadcasting career. I tried to be entertaining yet educational. One way was to introduce the DEW POINT as a better measure of the moisture content of the air. Remember, RELATIVE HUMIDITY is relative to what? The air temperature. It's the SPREAD between the air temp. & dew point that really matters. Here are some easy charts. You can see the RH fluctuates dramatically during the day along with the temperature while the dew point does not.

As you go up in height, the air cools. Clouds form when the temp. & dew point equal each other. Now back to the spread. On Thursday, our dew point was 79 with the air temp. 88! The spread was only 9 degrees, August like humidity. Look at today as northerly winds brought our dew points down into the 50s while our temps warmed into the 80s. The spread today is 25-30 degrees and it's why our air feels so comfortable.

But that is already about to change for Mother's Day. We're between two upper disturbances enjoying very nice May weather. The Northeast is cloudy, cool and rainy.

Our sunny skies are about to turn cloudy as the disturbance over the Rockies heads to the east.

70+ dew points are already showing up in south Texas and that's the moisture surge that will bring us a heavy rain threat. SPC's 7 day rain total has the heaviest to our north.

The NWS frontal maps are valid for Sunday AM, Sunday PM, Monday AM with the bottom view valid

for Tuesday AM. SPC has placed us in a level 2 severe risk for Monday.

Storms are already firing over west Texas with the middle graphic valid for Sunday followed by Monday's severe outlook. We're likely to see several waves of rain during the next 3-5 days with some dry days in-between.