Record High's, Frost & Rainfall Totals

by Kelly Smith, Meteorologist
September 13, 2012 12:00 AM


As we move out of summer and into the transitional fall season sometimes it feels like mother nature is taking us on a wild roller coaster ride. From record temperatures, to frost in slightly over 24 hours the first half of the week has been a wild ride.
The week started off with record and near record high temperatures ahead of a potent cold front. Temperatures Tuesday climbed into the 90's in many areas. Sioux City beat their daily record high temperature for Tuesday with an afternoon high of 98 degree's! Sioux Falls tied thier record from all the way back in 1895!



(Tuesday's High Temperatures)

Temperatures didn't stay hot for too long as a cold front moved through Tuesday night dropping temperatures significantly. In 24-hours, temperatures in the southeast dropped between 25 and 45 degree's!



(24-Hour Temperature Change from Tuesday afternoon to Wednesday afternoon)

Temperatures dropped so low in fact that it prompted frost advisories for many areas in the north and west. Forst Advisories were posted from Wednesday night and Thursday morning as temperatures were forecasted into the upper 30's.



(Frost Advisory issued Wednesday night through Thursday morning)

While, it may feel a little premature to see a frost so soon after record high temperatures, we are actually right on track to see our first frost as many of our average first frost dates are within 14 days!



(Median date of first fall frost)

In fact, the majority of the upper midwest usually see's the first fall freeze around the third and fourth week in September.



(Median dates of first freeze of 32 degree's)

It does however take slightly longer for many areas to see temperatures fall below freezing towards a hard freeze at 28 degree's. The average is usually around the first and second weeks of October.



(Median first frost dates for 28 degree's)

And even though this has been one of the warmest years on record, it is still quite possible and likely that the majority of our areas will meet our average freeze on time but back during the 60's it took almost until November!



(Latest first freeze)

Some areas on Wednesday morning hit their first frost. Aberdeen dropped below the freezing mark while Mobridge, and Huron dropped into the middle 30's.



(Thursday Morning's Low Temperatures)

Cloud cover left over from earlier rainfall caused temperatures in the southeast to stay more mild and also caused a bit of morning fog Thursday. Rainfall amounts from Wednesday and Thursday were lighter than expected but with how severe the drought has become it was a welcome sight for many. Heaviest amounts were in northwest Iowa where showers lingered for the majority of Wednesday afternoon and evening.



(48 Hour Rain Totals Wednesday through Thursday)

Despite light rainfall on Wednesday, the drought monitor still maintains very dry conditions with over 50 percent of South Dakota in an extreme drought category. This week's drought monitor stayed somewhat steady with the southeast still suffering from and exceptional drought.

(Current Drought Monitor)