If you thought you were going to be able to get your garden planted this weekend, you might want to think again. A cold spanking from Mother Nature is in the offing for the region, with temperatures forecast to be as much as 20 degrees below normal. The weather pattern is caused by a big low coming from the intermountain west across Idaho and Wyoming. It’s going to park over South Dakota, and that will draw down both colder air and precipitation.
Here are three things to know about what’s ahead:
1. The lowest temperatures are forecast for Sunday night, down to 35 degrees. That is above freezing, but there is a chance the forecast could dip lower as the date nears. If so, the National Weather Service will issue a frost advisory. In that event, be ready to bring what plants you can indoors, and cover the rest.
2. The average last day for a freeze is between now and May 22 for the region. That doesn’t mean freezes cannot happen after that point. It’s an average date. Some years the last frost is earlier, and some years it is later. Because of that, it is not generally recommended to plant warm-season vegetables, like tomatoes and peppers, before May 31. Those plants, in addition to not bearing up well to frost, don’t really like overnight temperatures much below 55.
3. Rain is in the forecast, but is running on a clear north to south gradient. Those further south are likely to get wetter than those further north.
“We’ll be below normal the entire week,” said Ken Simosko with the National Weather Service out of Bismarck. “But we will be back into summer time and severe weather not too far into the future.”