I just found this information at
http://www.datafellows.com/v-descs/tempest.htm .  I quote:
 "NAME: Tempest
ALIAS: TEMPEST.TEM
There is no virus known by this name to Data Fellows anti-virus products.
However, we sometimes get queries about 'Tempest virus', since the text
"TEMPEST" is sometimes visible to users of Quantum Fireball Tempest hard
drives.
During the manufacture and testing of the Fireball drives, a data pattern is
used which writes the text string "Tempest" all over the hard drive. This is
a part of the normal testing process for all disk drives and is not
indicative of any hardware problem. This text string is residual test data
which is overwritten by the customer during normal operation and is not
cause for any concern.

However, if a data corruption occurs for some other reason, the text
"TEMPEST" might become visible. For example, if a document file is
cross-linked to an unused area of the disk, the user would see a part of his
document to be replaced with "TEMPEST" texts.

This is not caused by a virus and is not a problem of the Fireball drives
themselves. "

This isn't much help but the next to last paragraph seems to point to some
data corruption.  Is this a Quantum Fireball drive?

Ben Moore
[log in to unmask]

[Analysis: Mikko Hypponen, Data Fellows]

>At 04:37 PM 6/4/98 +0000, you wrote:
>>Just before 95b ate my C partition and all the programs on it
>>renamed all the directories Tempest.tem  - what is that and how can I
>>avoid it happening again? I just found another 16 directories with
>>that same name in the partition  H:....... after re-installing
>>95b.
>>
>>Michael Beechey, a Canuck in Sucre, Bolivia