Contrail, Aviaticus Cloud Viewing Forecast Periodically Updated

Central Wisconsin Flyway Forecast and Summary 5/5/2015

The Central Wisconsin Flyway is right on the edge of a boundary line (sheet) with heavy clouds to the South and dry clear skies to the North so we should see some aviaticus (contrail) formations today unless the dryer air pushes south over the Flyway.  The Rapid Update Cycle Map is showing conditions for contrail formations favorable to the south, but it appears the cloud cover is too heavy to matter.


Central Wisconsin Flyway Forecast and Summary 5/2/2015

I was out of town most of day so it was interesting to view another flight pattern  producing mostly non-persistent aviaticus and a few lasting segments in a double-layered clouded sky, cumulus and light upper scattered sheets.

Back home toward dusk only whiffs were being laid and in this short video they can not be seen:

At the time of the video dry air was passing over the Flyway from the west shown as the dark swath on the moisture map:

Conditions should be good for aviaticus formation all day tomorrow ahead of Sunday evening's predicted thunderstorms.


Central Wisconsin Flyway Summary and Forecast 5/1/2015:  Yesterday began with a full morning of no trails, not a whiff or a pencil.  Just a sun-filled sky dotted with the summer-like white cumulus.  Then about 1 PM CT with some moister upper air, short non-persistent spits were forming from the afternoon east bound.  The aviaticus trails grew longer as the afternoon progressed indicating a boundary sheet was entering our Flyway preceding a thicker cloud bank.  By dusk persistent aviaticus continued forming and in the far west horizon a layer of white clouds could be seen creeping in.  In the morning thin sheets of upper clouds were still present and the Flyway was still marked with lateral aviaticus clouds holding together for example 15 minutes before dissipating, and heavier, broken patches of high natural clouds followed.  The natural cloud bank may continue to thicken to where aviaticus will not be viewed this afternoon and it appears this bank will pass over and the trailing edge may be a boundary sheet where trails will form until dryer air follows this.

At 1:10 PM CT yesterday the airliners started to leave short trails, here is a video of 4 flights that passed overhead 37,000-40,000'. Video at 24X speed (Please excuse the poor quality of this clip, I'm just starting to work with a screen recorder):

By 6:30 PM CT Skies had many persistent segments in the boundary sheet as a cloud layer approaches:

http://theorioninitiative2.blogspot.com/2015/04/forecasting-day-long-aviaticus-cloud.html

How Contrail Form into Milky Opaque Sheets

Yesterday was a full day of persistent to spreading cirrus aviaticus clouds (contrails).  As the first line of east to west air traffic traversed through our Central Wisconsin Flyway, horizon to horizon trails began to form from the water vapor attaching to cloud condensation nuclei (CCN) from the jet exhaust at an altitude between 32000-36000'. From flightradar24

Moist air continued to push in from the southwest following the pattern of the last 4 days, forming a boundary line (sheet) roughly along and beneath the regular air traffic pattern. From Infrared Map Site

Infrared

Moisture  From NOAA Water Vapor Site

At that time 7:30-8:00 AM CT the high cirrus were moving through the Flyway as the air mass slowly spread to the north.  

From the northern edge of the east west weather and air traffic pattern looking south:

Looking North of the Flyway:

By 9:30 AM the boundary line with both natural and aviaticus cirrus clouds drifted north and this continued throughout the day.

Looking East as Thin Clouds Drift Past the Flyway Going North.  A typical view seen most of the entire day.

As the cloud cover progressively thickened (optical density OD) from a combination of natural clouds and the boundary sheet area of the flyway which by then had been striped with many additional persistent clouds,  a sort of nuclei and moisture saturation occurred and typical for this type of event a sun dog formed from the natural and cirrostratus aviaticus ice clouds.

Looking South into the Flyway 11:00 AM

Note: Even NASA's Rapid Update Cycle RUC Map below, based on the Appleman Chart got this one right.

The 3 yellow circles across the center of the Wisconsin Flyway were a predictor of contrail formations:

http://theorioninitiative2.blogspot.com/2015/04/massive-day-long-contrail-event-of.html

Contrail (Aviaticus Clouds) Forecast for Central Wisconsin: Great Day for Photography if You Want to Avoid Man-made Clouds

A wide swath of dry upper air slightly streak with areas of moisture but without any distinct boundary lines will be over the Wisconsin Flyway today.  We should have some hit and miss aviaticus trails tomorrow and Thursday as conditions become a bit more mixed and complex. I'll try to post an update if boundary sheets with moist air become evident.

Update: Wrong! Before noon the dry upper air pushed north and cirrus and sections of cirrostratus moved in from the a southwest front.  Only short trails were seen earlier but as the dry air was replaced small segments of persistent aviaticus clouds (contrails) were scattered about though for the most part trails remained short with quick dissipation. This continued to increase into the afternoon dividing the state into two hemispheres, the dividing line going right over my location. So looking north I would see clear skies, south thicken cirrus of both natural and aviaticus. 

A Boundary line is shown below but again the boundary sheet of moister air reaches further north of the line as this mass inches north so contrails (aviaticus clouds) and longer non-persistent trails formed.  Oddly, the meteorologist were all correct, we had sun all day as the clouds were too thin to block it. How much of the cloudiness was cirrostratus aviaticus is the question.  Natural cirrus were present in the early morning but the continual additions of nuclei to the moving boundary sheets may be the greatest factor. This is why meteorologist need to make contrail forecasts.  Sunny skies do not mean clear blue skies especially along the flight corridors.                                  

                                               Infrared Map: From NOAA Site

Moisture Map, Darker Area indicates Drier Air: From NOAA Site

From the Boundary Line Looking South into the Flyway

http://theorioninitiative2.blogspot.com/2015/04/contrail-aviaticus-clouds-forecast-for.html