0-1% Humidity documented by the Bureau of Meteorology
Extreme low humidity in Mildura today, punching the values into a calculator resulted in a reading of 0.4% humidity at 4:04pm. Air temp 30.4C, dewpoint -41.1C
A lot of people believe that extreme low humidity readings of under 1%, 2% etc and whatnot is the stuff of fiction, well, no it is not.
That's quite incredible! I would be interested to know how that is actually physically possible.
I got no idea, but evidently it is possible!
You can see that the wet bulb thermometer has failed a couple of times in those observations, which leads me to believe that the humidity got so low that it can't actually be registered. I am a weather enthusiast, and never seen a -41C dewpoint at 30C before in this country.
You can see that the wet bulb thermometer has failed a couple of times in those observations, which leads me to believe that the humidity got so low that it can't actually be registered. I am a weather enthusiast, and never seen a -41C dewpoint at 30C before in this country.
Hi Sab,
As you alluded too, maybe it is due to an instrumentation error or some limitation of the
instrumentation?
It would be worth dropping a line to the Bureau and asking them.
If you pass on their response, I am sure many of us would be interested to
hear the outcome.
As you alluded too, maybe it is due to an instrumentation error or some limitation of the
instrumentation?
I think you'll find it is real. Kalgoorlie and the surrounding goldfields had something similar happen last week, too. I'm pretty sure I recall it happening a few times in the last 5 years or so here in WA, but not every summer, though.
Ok, so it's not -41, but it is 1% RH! hmm, and the next tweet says the dew point got as low as -35. So there you go.
The only time I've really seen the wet bulb go kooky is during cyclonic events when the constantly strong wind dries the wet bulb out and then it does give false readings.
I think you'll find it is real. Kalgoorlie and the surrounding goldfields had something similar happen last week, too. I'm pretty sure I recall it happening a few times in the last 5 years or so here in WA, but not every summer, though.
Ok, so it's not -41, but it is 1% RH! hmm, and the next tweet says the dew point got as low as -35. So there you go.
The only time I've really seen the wet bulb go kooky is during cyclonic events when the constantly strong wind dries the wet bulb out and then it does give false readings.
It's real indeed. All surrounding stations have been recording humidities of 2-3% at the same time. The Mildura weather station is a reliable, active station, There is no reason to doubt the readings. Most people elsewhere in the world would find these extreme low humidities to be the stuff of fiction, but no way, it is very real. The instrument is reliable and functioning correctly, after cutting out a few times, the humidity readings do show a valid observation compared to other stations in the area.
That -41.1C dewpoint is legit. The dewpoint / RH readings cut out because the air became so dry in those instances that the wet bulb thermometer failed. And going by the latest obs it keeps functioning after dropping out multiple times, that tells me that the instrument is working properly.
I am going to contact the BOM tomorrow, this could well be world record....
Last edited by pgc hunter; 20-10-2013 at 03:36 AM.
I recall that Ian Healy was remarking - during the Perth Test - that the RH dropped from 22% to 10%, between 8:30am and 10:30am. That seems like a sharp fall in just two hours. To me, anyway.
It might have been the second day's play, for those playing at home.
I recall that Ian Healy was remarking - during the Perth Test - that the RH dropped from 22% to 10%, between 8:30am and 10:30am. That seems like a sharp fall in just two hours. To me, anyway.
That's not unreasonable. Here at 06:00 this morning it was ~18C and 90% RH. At 15:00 it was ~42C and 10% RH. And that was with the garden sprinklers running all morning. Observe how the graphs are almost mirror images.
Here is a photo of my clock on the side of my ute under cover , camping at 2.20 this afternoon , Kunanarra WA .
You beat me too it!
