Its freezing at night, thaw and sunny in day. Say 25 degli. Night, 38 sunny day. When trees start to bud the weather may be good but sap/syrup will be bad. Also if its getting too warm in day sap is like milk. Keep it 35 degrees and its good, 60 for a day and its bad. Once you tap you have 4 weeks till the tree will heal enough and stop giving sap. Sap comes in runs, nothing for a few days and then will fill a 4 gal bucket in a day. Try and find someone in area that does it. They will know when to tap.