Dry Weather of Late Just Making it Hotter

June is, on average, our wettest month of the year.  For some spots, though, it was far from that.

Rainfall amounts always vary from place to place, especially during the summer months when thunderstorms only affect small areas.  This month, though, the differences seem bigger than usual.

Here are some of the rainfall stats from June from across the region:
DuBois:  4.62"
Clearfield:  4.03"
State College:  3.67"
Johnstown:  1.47"
Altoona:  0.61"

And with the first 10 days of July in the books, most places have seen less than a quarter inch of rain so far this month. 

Even after a wet spring, the ground has really dried out across much of the area after the recent stretch of weather.  That doesn't just turn the lawns brown, but it starts to affect the weather.

Our weather tends to become more desert-like.  Deserts have hot, dry days followed by cool nights.  When the ground is moist, some of the sun's energy goes towards evaporating the moisture while the rest goes towards heating the ground.  When there is very little moisture in the ground, almost all of the sun's energy goes to heating the ground since there is so little moisture to evaporate.  The result is warmer days, but generally lower humidity.  If you've noticed lately, we have had a lot of very warm and even hot afternoons that aren't all that humid.  We can have humid days in dry patterns, but they generally aren't as frequent and it generally isn't as humid as if we were in a wet pattern.  With the lower dewpoints associated with lower humidity, our nights also tend to be cooler and more comfortable.

It can be difficult to get out of these patterns because thunderstorms thrive in moist airmasses.  With the dry ground and the lower humidity, thunderstorms are less likely to form.

--Meteorologist Brian Thompson