Range forecast: clouds and contrails


Message posted by Paul on February 21, 2011 at 15:19:44 PST:

Nothing beats looking out the window, however, there are some short term forecasts that might help. You need to know your Zulu dates and times for this stuff.

Edwards AFB has a forecast for R-2508 that includes contrail levels if any.
https://bsx.edwards.af.mil/text/hprng.htm
https://bsx.edwards.af.mil/text/topsfcst.htm
No flight ops today so here is an older forecast that shows contrails levels expected to be between 32 and 36 thousand feet.
http://webcache.googleusercontent.com/search?q=cache:wjlacG9dm-YJ:https://bsx.edwards.af.mil/text/hprng.htm+r-2508+forecast+example&cd=1&hl=en&ct=clnk&gl=us&source=www.google.com

There is a contrail forecast model. It really is more of a nowcast than a forecast but you can put it into motion and see how things are trending. I think it deals with high bypass engines the airliners use and not the low bypass engines in jet fighters.
http://www-angler.larc.nasa.gov/cgi-bin/site/showdoc?docid=33&cmd=latest
The mb (millibar) levels have approximate altitude equivalents:
http://www.wrh.noaa.gov/slc/general/AFD_FAQs.php#3
I would say the 400 to 200 mb area is the most important.

Area forecasts from the Aviation weather center show cloud layers and coverage.
http://aviationweather.gov/products/fa/?area=saltlakecity
Looking an southern Nevada:
"SRN NV...FEW100 SCT150 BKN CI. OTLK...VFR"
Decodes as few clouds at 10,000 scattered clouds at 15,000 and a broken cirrus layer. I like a broken to scattered cirrus layer. Jets will sometimes appear as a high contrast silhouette against these clouds and having some cirrus around increases the chance for contrails is some parts of the sky. Here is the complete list of conctractions they use:
http://aviationweather.gov/static/info/awc-contractions-contsort.pdf

This radar pic from edwards (outdated right now due to no flight ops) can help you familiarize the range areas in relation to county lines.
https://bsx.edwards.af.mil/nexrad/CANV.JPG

1 kilometer resolution visible sat loop:
http://sat.wrh.noaa.gov/satellite/loopsat.php?wfo=vef&area=west&type=vis&size=1

2 kilometer resolution IR sat loop:
http://sat.wrh.noaa.gov/satellite/loopsat.php?wfo=vef&area=west&type=ir&size=2

24-hr Probability of 0.10 inch of rainfall:
http://www.wrh.noaa.gov/vef/prob10.php


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