September ended slightly warmer and noticeably drier than normal across Alpena County, but one powerful midmonth storm produced a daily rainfall record before a long dry stretch settled in. The National Weather Service reported that the county’s average temperature was 59.9 degrees, compared with a normal September average of 59 degrees.
The weather pattern was reflected along the Lake Huron shore in Alpena as October began. Rainwater pooled on the walkway at Starlight Beach on Thursday, while gray skies and steady rain opened the new month.
A warmer-than-normal September
The month’s temperature departure was modest, according to National Weather Service meteorologist Eleanor Delizio of the agency’s Gaylord office. September’s average was nearly 1 degree above normal, but the month still moved through a wide range of conditions typical of the transition from summer to fall.
“It was almost a degree above normal for average temperature,” Delizio said.
September began with its warmest reading. The high reached 86 degrees on Sept. 1, which was above normal for that date but well below Alpena’s historical record high of 99 degrees, set in 1953.
“That was above normal but the record for that day was 99 degrees, which was set in 1953,” she said.
The coolest reading arrived near the end of the month, when temperatures fell to 37 degrees on Sept. 26. That was still well above the September record low of 23 degrees, set in 1942.
Those readings — a mid-80s afternoon at the start of the month and an upper-30s morning late in September — showed the seasonal shift, even though the monthly average remained just above normal.
One rainy day accounted for more than half the month’s total
Rainfall showed a clearer departure from average conditions. Alpena recorded 2.03 inches of rain during September, 0.81 inches below the normal monthly total of 2.84 inches. The total ranked as the 31st-lowest September precipitation amount in the local record.
“That is 0.81 inches below normal. It is also the 31st lowest precipitation total on record,” Delizio said.
September rainfall records show how variable the month can be in Alpena. The wettest September produced 10.4 inches in 1937, while the driest brought only 0.28 inches in 1979. This year’s total was far from either extreme, but it landed clearly on the dry side of the historical range.
Rainfall was also unevenly distributed. The month began with lighter amounts, followed by a single heavy day in the middle of September. Most of the remaining weeks were dry, with only a small amount of rain recorded on the final day.
“The rain was fairly spread out; we had a little bit at the beginning of the month. Our record-breaking rain arrived on September 15, and then we were pretty dry for the last half of the month,” she said.
Alpena measured 1.24 inches of rain on Sept. 15, surpassing the previous daily record of 1.17 inches set in 1954. That one-day total made up more than half of September’s entire rainfall. After the storm passed, measurable rain was scarce until the month ended.
“We did get 0.2 inches of rain on the last day of the month,” Delizio said.
No drought in Alpena County
Despite the below-normal rainfall and dry second half, the county was not experiencing drought conditions. Delizio said no part of Alpena County was currently in drought, although the northern portion of neighboring Presque Isle County was the closest area reporting drought.
“No areas of Alpena County are currently experiencing drought conditions. The closest area experiencing drought is the northern portion of Presque Isle County,” she said.
Overall, the National Weather Service characterized September as a month that stayed close to normal on temperature while running short on precipitation. The rainfall deficit was concentrated after the middle of the month, leaving Alpena with a slightly warm September, a record-setting rainy day and an extended dry finish.
“For September in Alpena County, overall, it was just slightly above normal with the temperatures. The area was slightly below normal with precipitation; we did have a stretch of dry weather at the end of the month,” she said.