This list is used to request missing or retrospective data. In the spirit of community that has made Unidata a success, subscribers help each other by supplying data that they have available (note that you must be subscribed to the list to post a request). Please be reasonable in your requests; don't expect someone to dig out six months of radiosonde data from 20 years ago.

To see the collection of prior postings to the list, visit the needdata Archives.

You can subscribe to the list, or change your existing subscription, in the sections below.

Subscribe to needdata by filling out the following form. You will be sent email requesting confirmation, to prevent others from gratuitously subscribing you. This is a hidden list, which means that the list of members is available only to the list administrator.

Your email address:
Your name (optional):
You may enter a privacy password below. This provides only mild security, but should prevent others from messing with your subscription. Do not use a valuable password as it will occasionally be emailed back to you in cleartext. If you choose not to enter a password, one will be automatically generated for you, and it will be sent to you once you've confirmed your subscription. You can always request a mail-back of your password when you edit your personal options.
Pick a password:
Reenter password to confirm:
Which language do you prefer to display your messages?	English (USA)
Would you like to receive list mail batched in a daily digest?	No Yes