Conditions will stay dry and quite warm through the President’s Day Weekend, although the ridge of high pressure responsible for the aforementioned will be flat enough to allow variable amounts of cloudiness to pass over the Great Basin. Friday’s high temperatures will approach record levels (mid to upper 60s) and will stay in the 60s throughout the weekend. There is increasing indication that a storm will move through the region next Wednesday and Thursday bringing high snow levels initially, which will drop to near but likely just above the valley floor on Thursday.

pressure cooker

As a follow-up to yesterday’s column, Beryl asks: “Maybe you can explain this to me in a way that makes sense… no one else has been able. Pressure cookers rely on high pressure to generate high heat. Also, when you cover a pot of water, it gets to the boiling point faster, right? So… why doesn’t atmospheric pressure act the same way?”

Actually, it does. A pressure cooker is basically a closed pot that allows the pressure to build up inside as the water tries to boil. A pressure release valve on the top controls how much pressure builds (it’s meant to cook things… not blow up kitchens.) As pressure rises, the boiling point of water rises… up to about 250 degrees instead of 212 degrees for water boiling at standard pressure. At higher altitudes, just the opposite happens. With lower pressures, water boils at a lower temperature, cooking at a slower rate.

lid

As for putting a lid on a pot to speed up boiling, that’s a little different. Unless the lid is sealed to the pot (not a good idea), its presence only serves to keep the heat inside the pot, which shortens the time needs to get it up to a boil.

 

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