Upper level cloud base question...

I just got a email from a visitor asking if theres a way to find the upper Level cloud base…Heres the email he sent…

Message: I like you website; very helpful when planning hikes. I recently found the website through a KOMO4 link to local/independent weather stations. I really like the Cloud Base graph. It lets me know the ceiling of visibility. My question is related to hikes that take me through the cloud base and back out into the sun on high elevation hikes. Is it possible to figure out what elevation the top of the cloud formation is? Does the top of the cloud on the graph represent the true top of cloud elevation? If not, is it possible for you to do this?

How would you figure somthing like that out to find the Upper level cloud base.

Thanks, Mark.

there is some custom tags to show the cloud height from set to use downloaded metar, from memory…

So that custom tag will show the approximate upper level cloud base?

I looked in the custom tags and didnt see anything about Upper Cloud base from Metar location. Is there another way i could add this to my site? Thanks, Mark.


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is there a tag for this? If not…I’ll try and find another way to get the Info…thanks.

Perhaps the info you seek can be found in this book…

I am not at home just at the moment (had to take the kids to the doctor (tonsilitis)
, so your patience is appreciated

but try out the various metar tags , not sure which one, but one of them should pull out the cloud height info

The cloudbase graph you show is WD estimate cloudbase: the height at which the water vapour condensates and make a cloud (if any). This does NOT mean there could be a cloud. This estimation is only valid for low level clouds. The tags for this value are:

%cloudheightfeet%…Estimated cloud base height, feet, (based on dew point, and you height above sea level…enter
%cloudheightmeters%…Estimated cloud base height, metres, (based on dew point, and you height above sea

If you have a near Metar station you can retrieve it with WD and show with different tags:

%weatherreport% …current weather conditions from selected METAR
%metar/report=%NZAA.MET Insert downloaded METARS or weather reports/warnings.
Please replace NZAA.MET with the file name downloaded.Note: use

 and 
html tags
%uncodedmetar/report=%NZAA.MET Un decoded (raw) only
%extrametarlabel% …extra METAR label from the metar.gif
%metarcloudreport% …cloud METAR label from the metar.gif
%downloadedmetar1extrasky%.Sky conditions
%downloadedmetar1sky%…More sky conditions
%downloadedmetar1cloud%…Cloud conditions or weather
%downloadedmetar1press%…Barometer reading
%downloadedmetar1humi%…Humidity reading
%downloadedmetar1dewp%…Dew point reading
%downloadedmetar1temp%…Temperature reading
%downloadedmetar1tempcelsius%…Temperature reading in celsius
%downloadedmetar1wind%…Wind readings (speed and direction)
%downloadedmetar1location%.Metar name and time stamp
%downloadedmetar1vis%…Visibility
%downloadedmetar1name%…Just the metar name. (1st 10 metars only)
%downloadedmetar1time%…Just the time of update.(1st 10 metars only)
%downloadedmetar1rainlasthour% Rain in the last hour (if its available)
%downloadedmetar1windonly%…Shows just the windspeed only (1st 10 metars only)
%downloadedmetar1dironly%…Shows direction in letter (1st 10 metars only)
%downloadedmetar1dironlydeg%… Shows dir in degrees.(1st 10 metars only)
Repeat this for up to 50 downloaded airport metars (i.e %downloadedmetar2location% for the next one)

There is also a set of tags that I think they only work un the US:

US Navy

%usnavycloudheight1%…Cloud height from the ceilometer, feet
%usnavycloudheight2%…Cloud height from the ceilometer, feet
%usnavycloudheight3%…Cloud height from the ceilometer, feet
%usnavycloudtype1%…Cloud type
%usnavycloudtype2%…Cloud type
%usnavycloudtype3%…Cloud type
%watertempcelsius%…Water temperature, oC
%watertempfaren%…Water temperature, oF
%visibility%…Visibility (miles)
%visibilitykm%…Visibility (km)

But AFAIK neither the METAR, nor WD, will give him the number he wants which is the height of the TOP of the cloud layer.

Ah !! Sorry. For cloud top heights he must go for sounding graphs or satellite derived products.

So finding the top of the cloud base seems pretty difficult to figure out. Thanks for all your help…I’ll keep looking around to see if i can come up with somthing.

Sure you can find something like this for your zone:

http://nwcsaf.inm.es/SAFNWC_CTTH2_Europe_Open.html

A scientific question would be whether a value for an airport of cloud at a certain height above the runway, would be valid for the same height up a mountain. Mountains/hills can generate their own local clouds, like Mount Shasta. I would guess that ALITTLEweird1 sees similar effects on his local mountains.

The only reported cloud height data I’m aware of would be from pilot reports (PIREPS) available from a site like this and others. However, PIREPS don’t always contain cloud tops and are not regularly available for a location like a METAR. Also, pilots tend not to fly close to mountains to report could tops. :wink:

As Breitling mentioned, an upper air sounding may be useful for this.

Thanks for all the Info. I’m finding some interesting sites about this. As Niko said, the Mountain I’m referring too is over 4000 feet. My house is at about 800 and this mountain is only about 3 miles from here. The person that emailed me was talking about that 1 mountain. Its pretty much in the middle of no where and stands out like sore thumb cause the surrounding Mountains are about 3000 or so. Its a very Popular mountain for hikers, so i could see why someone would want this info. But i think based on where i live and where this mountain is, its going to be very difficult to find such data that hes wanting.


just set up a test metar download here, and after ticking, to use airport metars, in the custom web page setup, in the webfiles/web page setup
then, the custom tag,
%downloadedmetar1cloud%
gives the cloud type and height
i.e
BKN022

(broken cloud at 2,200 feet)

Is that for the bottom cloud base or the TOP layer cloud base? I was looking for the TOP layer level before you get back into Sun.

a metar just shows what clouds are provided by that metar station
in my case its the visible cloud layer
a metar station would need to have the ability to detect cloud layers above the visible cloud layer, and if present, then it will add those in, and that should also show up as another cloud type and height in the custom tag

Metar reports give always cloudbase heights (bottom of the cloud), expressed in feet AGL (Avobe Ground Level, not sea level). If there is more than one cloud layer, it gives heights of layers visible from the ground. You can see reports with a scattered below a broken below an overcast layer. You’ll never see a report with an overcast layer below any other. The ceilometer is unable to measure that.

Thanks for all your replys on this. As i wasnt sure what to tell the guy that asked this question.