-15-
_15_
Many of the weather reports issued by the Po Valley stations in the afternoon of the 26th do not correspond to the concept of a cold front, as it is usually understood. For example, the weak storm actiVity which began at the Malpensa airport immediately before 5 00 p.111. or
soon thereafter, when the front in all probability had already passed by, is not in strict conformity with the normal passage of a cold from, but neither is it out of the ordinary in this region during bad frontal situations. It is also difficult to explain the prolonged storm activity in the Turin area. It is posSible that the weak lowr building up north- west of Genoa contributed to accentuating the southern currents at high altitudes and the consequent effects due to orographic factors. Another possibility is that this {condition} is associated with the front at a high altitude, or it may be more readily explained by assuining that a large storm nucleus remained at that place because of its size and nature, abetted by the action of cooler air from above.
Reports from pilots [flying in the area] show that the storms hovering ovar the Malpensa airport, which was hit about 5:00 p.m., came frorn Gameri and Vercelli, that is, from the southwest, Slnce they were reported by those weather stations a little earlier in the afternoan. Instead, in the opinion of those who saw it, the storm on the Malpensa airport at about 5:00 seemed to be coming from the east.
Taking into consideration the slight Winds blomng if. the zone at that time and the lack of more recent observations of winds at high altitude, it may very well be that the storm actiVity reached the Malpensa airport from the east, although the high-altitude charts show a slight circula- tion from the southwest.
The atom activity which had its beginning to the southwest of Milan
and then extended rapidly eastward through the Po Valley, may be explained as indicating a cyclonic impulse, or a wave motion in the front. The exact determination of the successwe peeitions of the front both over land and at high altitude W111 never be poSSible since it seems unlikely that there will ever be full agreement as to the front's precise positions and its shifting course through Northern Italy. Nevertheless,
a careful exannnation of the data gathered by the weather stations of
the Western Po Valley and of the information supplied by the pilots who flew in the Milan area on the afternoon of the 26th, all Within the framework of a general analysm of conditions on land and at high altitude: will permit us to arrive at a precise enough and reliable description
of the weather prevailing in the zone at the time of the crash.
At 12:00 noon on June 26, 1959, Western Europe was under the influence of a weak westerly influx of Atlantic air slightly cooler than the existing air. advancing frm the West behind a relatively weak cold front which, upon reaching the Alps in the morning, Settled against them. baing held in check by the mountain chain and forming a weire motion along the Hanco-Swiss side of the chain. Not until early afternoon
did the front succeed in overcomng the obstacle and spreading over the Po Valley. Surface winds were very weak during the entire day over most of Europe. At an altitude of 700 MB there is noted a. weak gradient
Wind of about 15 knots pushing the front forward.
