Pruning Time is Near

We are waiting for some good weather to come around so that we can go in the vineyard and prune the vines. We will be pruning back to two buds so that the new shoots this year will have more of a synchronous beginning. We also hope to ward off the powdery, downy, and black rot infestations by following the advice of our vineyard consultant, Fritz Westover.
The weather has not been auspicious for pruning. One day it's sunny and the next day it is pouring down rain with gusting winds. This morning, we awoke to a covering of sleet resembling snow. This would not be good if our vines were in budbreak but they are still (thankfully) dormant.
The warm temperatures in the spring causes the dormant bud to deacclimate and become less cold hardy. As soils warm up, capillary action draws water up the trunk, and "sap flow" occurs as the grapevine re-establishes the vascular system between buds, canes and roots.¹ By the time of bud swell, rehydrated bud tissue is vulnerable to freeze injury at only a few degrees below freezing as shown in the figure below:²

More and more of our buds are exhibiting signs of very early bud swell but according to our friend, a vineyard manager in our area, bud break is still a month away.
References:
1. Tim Martinson, Grapes 101: How Grapevine Buds Gain and Lose Cold-Hardiness
2. Tom Zabadal, Winter Injury to Grapevines and Methods of Protection, Michigan State University, Extension Bulletin E2930, June 2007, pg. 7.