Many of us here in SE Arizona will not be outside today no matter how nice it is because of historic sports emergencies that will require viewing of the TEEVEE at all times. However, if we do go outside to BBQ some hot dogs or prepare other similar worthwhile foods common to “football day”, there will be LOTs of icy cirrus clouds to view, such as those in the photos.
However, there is also likely to be the quite odious contamination of these clouds by aircraft contrails as we have seen over the past few days. Aircraft produce long contrails when the air is at or near “ice saturation” and the temperatures at flight level are below about -35 C. Flight levels over Arizona for aircraft traversing the state are typically between 32,000 and 38,000 feet and the temperatures at those levels are almost always low enough for contrails. Its only the moisture that is usually missing to allow them to happen. These flight levels may be tuned depending on headwinds.
Often over Catalina, AZ, we only see contrails to the N for the heavily traveled airways above Casa Grande to PHX or to the S of TUS. Lately there seem to have been an abnormal of contrails. Not sure why. The TUS balloon soundings have suggested that it is damp up there from about 25,000 feet to more than 40,000 feet over the past couple of days, the highest levels of that moisture a bit high for wintertime. Perhaps that extra height explains the abnormal number of contrails.
OK, second post, still testing. 1-2-3, 1-2-3.