Thursday, January 29, 2015
Cold case review - Moe, Victoria - My analysis
This is the fourth in a four part series of posts about the classic 15 February 1963 incident near Moe, Victoria. In this post I attempt an analysis of the observation.
Comments and analysis:
1. This is a very puzzling case. I have, for some reason, always had the impression that the event lasted some minutes. It is clear that it did not. At most it lasted 15 to 16 seconds (McDonald 1967). The only other estimate of duration available, is that when it hovered. Brew himself said, this phase lasted 4-5 seconds. (VFSRS 1963.) It is therefore a short duration event.
2. The absolute size of the object is given by Brew as 25 feet by 9-10 feet. These estimates appear to have been made when the object was at its closest approach, estimated at 75 feet. An angular size of some 18 degrees is implied by these figures. This is equivalent to 36 full Moons side by side in the sky. However, these estimates of Brew's, may, or may not be accurate. Maybe it would be better to say that the more certain information is that the ratio of the object's diameter to its height (minus the top "antenna") was roughly 3 to 1.
3. The shape of the object, as shown in both the RAAF and VFSRS investigations, does not agree with the shape expected to be seen if the RAAF's tornado-like phenomenon suggestion is adopted. A tornado, in whatever form, would be expected to be taller than wider, shaped like a cone or rope shape.
4. The sound heard is another interesting aspect, variously described as "swishing, burbling-type sound" (RAAF); "swishing" (VFSRS) and "diggerydoo" (McDonald.) Both Charles and Trevor report hearing this loud and unusual noise at the same time.
5. A further unusual aspect is the possible correlation of a headache to Brew when "gazing at the perspex canopy." (VFSRS).
Is the RAAF's explanation viable?
6. What then are we to think of the RAAF's suggested tornado-like phenomenon? At first glance, the reported structured object; the headache; the noise and the shape, all appear to disagree with this suggestion. The RAAF report states that the CSIRO meteorological people were in some agreement with such an explanation.
7. The fact that the object descended from the cloud base; was moving in the direction of the wind (as stated by Brew but different from the RAAF); and was rotating in part, anti-clockwise; and went back into the cloud base in a few seconds, at first had me thinking "funnel cloud."
8. A "funnel cloud" is a funnel shaped cloud of condensed water dropletes associated with a rotating column of air. This funnel extends from the base of a cloud and does not reach the ground like a conventional tornado. Photographs of "funnel clouds" which I perused on the Internet reinforce the fact that the funnel is linked to the clouds and it does not detach from the cloud.
9. Brew described his object as descending from the clouds to a height of 75-100 feet and then going back up into the clouds. His estimate of time for the stationary phase is 4-5 seconds.
10. Two hours later, the weather observer at Yallourn stated the type of clouds visible then and there were "Fracto-Stratus." "These low gray clouds are small, thin, unorganized tatters that typically condense in the moisture beneath nimbostratus or cumulonimbus clouds." (Click here). The bases of these clouds are usually found near the ground to around 6,500 feet." Funnel clouds are usually associated with cumulonimbus or cumulus clouds.
11. A check on the Internet revealed a general concensus that sounds associated with funnel clouds are "similar to buzzing bees, or a rushing waterfall-like sound, roaring sucking sound." (Click here.)
12. Points favouring a funnel cloud as an explantion for the object seen at Moe, are:
1. They form in similar weather to that reported at Moe.
2.They do rotate.
3. They do appear grey in colour.
4.They have associated sounds similar to that described by the Brews.
5. They are of short duration, seconds to minutes.
6. They move in the direction of the prevailing wind.
7. They are most likely during the summer months, e.g. February.
8. White or blue glows have been reported in association with them.
Points against a funnel cloud:
1. They do not detach themselves from their associated cloud base.
2. Their description in the literature, does not match that reported by Brew.
However, you can see why the tornado-like phenomenon appealed to both the CSIRO and the RAAF .
Another possible meteorological explanation?
13. Interestingly, my review of the meteorological information on tornados and tornado-like phenomenon revealed that there might be an even better fit for the object seen at Moe.
That is, a "gustnado", which is short for a gust front tornado. Gustnados were not know about in 1963. The Australian Bureau of Meteorology describes them as follows:
"The gustnado has been accepted as a 'type of tornado' but is really a brief, intense vortex that forms on the leading edge of gust fronts. Scud and debris or dirt may be seen but a condensation funnel is usually absent. They will last from a few seconds to several minutes and are strong enough to cause minor damage. They are distinguished from a true tornado by their location under an advancing dark cloud bank, or shelf cloud ahead of the rain core. Although the air is rotating, this event is grouped more appropriately with straight-line winds (downbursts and microbursts)." (Click here.) The BOM website has an interesting photograph,, which shows a gustnado, taken in Melbourne, Victoria. The gustnado, if tipped on its side would appear as a grey, rotating, discoid form. (Click here for photo.)
The column is not connected to, nor has it developed from the cloud like a tornado or a funnel cloud. A gustnado lasts for from seconds to a few minutes.Unlike a tornado the rotating column of air does not extend all the way to the cloud base. They may only extend to 10 to 100 metres above the ground with no apparent connection to the cloud.
The Bureau of Meteorlogy's website Storm spotters Handbook says they have an anti-clockwise rotation. Like other funnels they may generate noise and light.
What did Brew see?
14. After reading all four posts in this series, which provides detailed information on the event, and the information provided on tornado-like phenomenon, you will have to make up your own mind what it was that Charles Brew saw on the morning of 15 February 1963.