OTTUMWA — The weekend forecast is coming into focus as the weather prepares for a sharp turn away from Thursday’s record warmth.
Ottumwa saw a high of 62 on Thursday, breaking the previous record of 58. The warm weather will be just a warm memory by the weekend. The National Weather Service expects rain to arrive in the Ottumwa area between noon and 5 p.m. Friday. It will change to all snow after 5 p.m., perhaps with some sleet as well. It will become all snow after 7 p.m.
A winter storm watch will go into effect for the Ottumwa area at 6 p.m. Friday and will remain in effect through Saturday evening.
Friday night’s accumulations will be minor. Forecasters expect less than an inch before the first round moves out of the area. That’s still enough to make things slick, so people will need to be careful as they venture out Saturday morning.
The second round of snow will bring a lot more. It arrives after noon Saturday. A high near 27 will allow the air to carry a lot of moisture, and the snow will continue until around midnight.
Forecasts shifted throughout the day Thursday, reflecting the Des Moines office’s uncertainty about the exact path the storm would take.
One early forecast from the National Weather Service suggested Ottumwa could see accumulations of 4-6 inches, while another during the day put the figure at 2-4 inches. The winter storm watch announcement put the figure at 3-7 inches, plus a potential light glaze of ice along the Iowa-Missouri border.
Complicating the forecast is the fact this storm could have very sharp lines between light snowfall and much heavier amounts.
The Des Moines office said this type of storm “can often produce sharp gradients where amounts vary over short distances.”
People with weekend plans should keep a close eye on the forecast for changes.