temperature rate of change

Hi,

What would be considered a fast rate of night time temperature change?
What is average? 1°/hr?

Thanks,
Dan

Dan wrote:
Hi,

What would be considered a fast rate of night time temperature change?
What is average? 1°/hr?

Thanks,
Dan



Depends on where you are. Best would be to access a weather site for the
area of interest and look at the hour-by-hour predicts. Here is an example:

http://tinyurl.com/kj3jb

with not a lot of variation all night (near the ocean). Would be much
more in the local deserts, etc. You can put your location in the url
above and get the info you want.

Phil

Dan wrote:
Hi,

What would be considered a fast rate of night time temperature change?
What is average? 1°/hr?

C or F?

It's gotta depend on your local environment. I live high and dry in
Colorado. A 20 deg F temp drop from sunset to sunrise is about normal
and most of that is in the first half of the night.
Cloud cover, humidity, and wind all influence temp changes here a lot.
YMMV

Shawn

It depends on time of year and weather too. I'm out in the High Mojave
Desert, now yesterday we had light overcast and it never got above 60F, last
night at 4am it was still 50F, but I've seen days of clear sky with 50F and
that night by 7pm it would be at lest 35F and by 4am it's 18F. During the
summer time we can go from a day high of 100+F to a night temp at midnight
of 60F and times it'll only drop down to 80F at night.


--

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"Dan" wrote in message
.. .
Hi,

What would be considered a fast rate of night time temperature change?
What is average? 1°/hr?

Thanks,
Dan

Starlord wrote:
It depends on time of year and weather too. I'm out in the High Mojave
Desert, now yesterday we had light overcast and it never got above 60F, last
night at 4am it was still 50F, but I've seen days of clear sky with 50F and
that night by 7pm it would be at lest 35F and by 4am it's 18F. During the
summer time we can go from a day high of 100+F to a night temp at midnight
of 60F and times it'll only drop down to 80F at night.

It also depends on your local topography. JPL's Table Mountain
Observatory is at 7500 ft, on a mountaintop at the east end of the
San Gabriel Mountains, overlooking a valley about 3000 ft below.
(That valley is where the San Andreas fault runs, btw.) It's quite
common for the temperature at the observatory to drop a few degrees
at sunset and then stay constant the whole rest of the night! All
that cold air just sinks down into the valley and attacks Wrightwood.

-- Bill Owen

Bill Owen wrote:
Starlord wrote:

It depends on time of year and weather too. I'm out in the High Mojave
Desert, now yesterday we had light overcast and it never got above
60F, last night at 4am it was still 50F, but I've seen days of clear
sky with 50F and that night by 7pm it would be at lest 35F and by 4am
it's 18F. During the summer time we can go from a day high of 100+F to
a night temp at midnight of 60F and times it'll only drop down to 80F
at night.


It also depends on your local topography. JPL's Table Mountain
Observatory is at 7500 ft, on a mountaintop at the east end of the
San Gabriel Mountains, overlooking a valley about 3000 ft below.
(That valley is where the San Andreas fault runs, btw.) It's quite
common for the temperature at the observatory to drop a few degrees
at sunset and then stay constant the whole rest of the night! All
that cold air just sinks down into the valley and attacks Wrightwood.

The city of Gunnison, CO, about 50 miles west of me is one of the
coldest cities in the U.S. because of this phenomenon.
If a strong downslope wind blows we can get a lot of warming (chinook
winds). Interesting when it's 15 F when you go to bed in the evening
and 40 F when you wake up in the morning. Not great for observing
though, 45-60 mph winds.

Shawn

I'm out in Rosamond, I can see the lights of Wrightwoods ski runs from here
and this is about 35 miles north on the US Plate side of the S.A. Fault
line. I'm just about 13 miles from Mojave Spaceport.


--

The Lone Sidewalk Astronomer of Rosamond
Telescope Buyers FAQ
http://home.inreach.com/starlord
Sidewalk Astronomy
www.sidewalkastronomy.info
Astronomy Net Online Gift Shop
http://www.cafepress.com/astronomy_net
In Garden Online Gift Shop
http://www.cafepress.com/ingarden
Blast Off Online Gift Shop
http://www.cafepress.com/starlords




"Bill Owen" wrote in message
...
It also depends on your local topography. JPL's Table Mountain
Observatory is at 7500 ft, on a mountaintop at the east end of the
San Gabriel Mountains, overlooking a valley about 3000 ft below.
(That valley is where the San Andreas fault runs, btw.) It's quite
common for the temperature at the observatory to drop a few degrees
at sunset and then stay constant the whole rest of the night! All
that cold air just sinks down into the valley and attacks Wrightwood.

-- Bill Owen