Groundhog Day is a multi-faceted observance, both in the Elder tradition of Braucherei and in Urglaawe. February 2 presents us with a thinner "veil" among the realms/worlds, and that the first of the land spirits/wights take this opportunity to return from the Wild Hunt. The groundhog represents the "otherworldly messenger," who (in a manner similar to Ratatosk on Yggdrasil) runs through his burrow, which has openings in each of the nine worlds. Thus, the groundhog brings reports from the other worlds.
For an agricultural people, the upcoming weather would be of primary importance, which is perhaps the root of the reason that the groundhog and his weather prediction has lived on. However, this is typically only one small part of his message. Anyone who has ever been to a Grundsau Lodge on February 2 will know that the groundhog delivers numerous prognostications. Granted, in the Lodges, most of these are in jest, but journey-work done on February 2 or other, more esoteric works, are said to be more revealing.
Second is the tradition of February 2 celebrating the Hearth goddess, who would be Frigg, as well as the feminine creative energies. Female ancestors are also celebrated on Feb. 2, which is consistent with some other Heathen groups' Disir blots at this time of year. As a result of these creative energies, the Butzemann (an activated scarecrow) is ceremonially given birth (more technically, he is given "rebirth" through the remnants of last year's crop). There are ceremonies that Urglaawe has inherited from Braucherei for his rebirth and appointment as protector of the land. He sticks around until he is burned sometime between the autumn equinox and Allelieweziel (Halloween). There are some great stories about what happens after Allelieweziel.
One other thing that is to happen on February 2 in relation to Frigg: we are to clean out our hearths, fireplaces, candlestick, or whatever place we use as our primary spot for fire. After the site or item is cleaned, we are to light a new fire using birch. If there is a central hearth through a community celebration, ember pots may be used to take the new flame from the central fire to the home hearth.
The cleaning of the Hearth is the beginning of the time of Spring Cleaning. We have from now until Walpurgisnacht (April 30) to get our homes in order in preparation for Holle's return. :)