So the Weather Channel says the current temp in Southern California is 83F, with relative humidity at TWO percent. How is that even possible? It’s been hovering around 5 to 6 percent since last week, and even that’s been crazy low. How low can humidity possibly get?
But I guess it explains why my skin feels like I’m becoming a Sleestak.
Desert on one side, ocean on the other, Santa Ana winds, humidity can drop pretty low.
Well, it’s dry air coming across the desert, blowing all the moist air out to sea. Still, I know what you’re saying. One article said it’s drier than the desert would be in mid-August, so how’s that work? I think the 2% is very localized though, maybe right next to active fires? The 5% is more spread out, but that’s already hella dry! May God have mercy on us.
Sinking air dries out. Take some desert air blowing down a mountain range and it can get pretty dry.
Math!
Here in the low desert during our annual run-up to [del]Hell[/del] Summer from April to June, every few years it get to 2% humidity.* When it does, the radio weather guy comments, “It just can’t go any lower.”
*Single-digits almost every year but below 6% is rare.
In the unlikely event this thread gets moved to the Pit, I’ll share my “Drier than a” joke.
It doesn’t dry out - the moisture content (the absolute humidity, expressed in mass of water per mass of dry air) doesn’t change. What does happen is that as the air sinks, its temperature increases due to adiabatic heating, which results in the relative humidity (the actual amount of water in the air compared to the maximum possible amount at that temperature) being decreased. Relative humidity is what gets reported in weather stats.
2%? positively tropical!
Call me when the humidity falls below 0.5%… 
It is currently 64F with 77% humidity. Freezing here. 
16 F with a blanket of snow. Don’t tell me about freezing.
You don’t know some freezing!
It’s -20°C (-4°F) today, yesterday was -25°C (-13°F) and that’s without the wind chill effect.
Interestingly, it’s also 82.7% Rh!?
I was just working on a project in Bozeman Mt. and they average 12 F and 90% humidity in December. In my calculations, I realized this is really on .0015 lb of water/lb of air and any heat being applied to the air would drop the humidity to zero very quickly.
A few mornings ago the temperature dropped to 59 degrees F in Hilo (Hawaii). I was freezing and actually had to put on my long sleeve sweat shirt. It later moved up to the high 70’s, but that was one cold morning!
I heard a rumor that it’s going to be in the low 50s sometime this week. 
It’s up to the high 30s – too warm!!!
