Summons to Vaisala Oyj’s Annual General Meeting

Vaisala Oyj’s Annual General Meeting will be held on Tuesday 22 March, 2005, at 5 p.m. at the company’s head office, Vanha Nurmijärventie 21, 01670 Vantaa.

Following items will be on the agenda of the Annual General Meeting:

1. The items specified in Article 13 of the Articles of Association.
2. Vaisala Oyj Board of Directors’ proposal that authorization be granted to the Board to acquire and dispose the company’s A-shares.

The Board of Directors propose to the Annual General Meeting held on Tuesday 22 March 2005 that authorization be granted to the Board to acquire and dispose the company’s A-shares according to the Finnish Companies Act as follows:

Acquisition
- Shares shall be acquired not in proportion to current shareholdings through public trading arranged by the Helsinki Stock Exchange
- The shares will be acquired at the market price formed during public trading
- The number of the shares which may be acquired shall not exceed 35,000
- The shares will be used to settle the share-based incentive program designed for Vaisala Oyj’s key personnel
- The authorization is valid for one year from the date of the Annual General Meeting, expiring on 22 March 2006
- The acquisition will reduce Vaisala Oyj’s distributable equity

Disposal
- The Board of Directors are authorized to decide on the disposal of maximum of 35,000 shares
- The shares can be disposed according to the regulations of the share-based incentive program designed for Vaisala Oyj’s key personnel, in manner decided by the Board of Directors
- The shares will be disposed at the market value formed during public trading
- The authorization is valid for one year from the date of the Annual General Meeting, expiring on 22 March 2006

Right of attendance
 Shareholders who are registered in the company’s share register maintained by the Finnish Central Securities Depository Ltd by 11 March 2005 may attend the Annual General Meeting. Shareholders whose shares have not been transferred to the book-entry securities system may also attend the Annual General Meeting provided that such shareholders were registered in the company’s share register before 21 October 1994. In such cases, shareholders must present evidence that their shareholding rights have not been transferred to the book-entry securities system.

Documentation
Documents relating to financial statements and the Board’s proposals to the Annual General Meeting are available as copies for the shareholders to see at the company’s head office in Vantaa, Vanha Nurmijärventie 21, for a week before the Annual General Meeting. On request, copies will be sent to shareholders.

Notice of attendance
Shareholders wishing to attend the Annual General Meeting must notify the company no later than 4 p.m. on Monday 14 March 2005. Notification can be made either by letter addressed to Vaisala Oyj, Nina Andersin, P.O.Box 26, FIN-00421 Helsinki, Finland, by telefax to +358 9 8949 2206, by e-mail at nina.andersin@vaisala.com, or by telephone on weekdays between 9 to 12 p.m., tel. +358 9 8949 2201.

Letter authorizing a proxy to vote on behalf of a shareholder should be sent to the company before expiry of the notification.

Election of the members of the Board of Directors and auditors
Shareholders representing more than 10 percent of all the votes in the company have informed that they will propose to the Annual General Meeting held on Tuesday 22 March 2005 that:

Two members of the Board of Directors, Mr Raimo Voipio and Mr Mikko Niinivaara, who were to retire by rotation, and Vaisala Oyj’s current Authorized Public Accountants PriceWaterhouseCoopers Oy and Mr Jukka Ala-Mello APA, to be re-elected for the next term of office, in accordance with the Articles of Association. The two members of the Board of Directors and Vaisala Oyj’s current Authorized Public Accountants have given their consent for the re-election.

The invitation to the Annual General Meeting will be published in Helsingin Sanomat and Kauppalehti newspapers on Thursday, 10 February 2005. An English language version will be available on the Vaisala Group homepage www.vaisala.com on the same day.