The featured graph is a time series from the Spencer airport sensor showing air temps, wind speeds, and visibility distance. The morning hours saw a round of snowfall followed by improving conditions where temperatures rose to above freezing in many locations followed by a frontal passage with rapidly deteoriating conditions followed by a decrease in wind speeds with improving visibilities by bitterly cold temperatures. All of that makes for quite the weather day! The next winter storm will be here this evening already!

Voting:
Good = 23
Bad = 6

Tags:   coldfront  

The cold front passage on Sunday was one for the record books due to the drastic and rapid change in temperature. Today's featured plot is a time series from Ottumwa showing an amazing drop of 80 degrees in 12 hours. Note this is a drop from an air temperature of 60 to a wind chill value of -20. The actual air temperature drop was around 60 degrees in just 12 hours! Some analysis is currently being done to compare this drop to others in the past, stay tuned.

Voting:
Good = 33
Bad = 16

Tags:   coldfront   extreme  

A very intense cold front crossed the state on Sunday dropping our temperatures from the 40s and 50s almost immediately to values below freezing. The featured graph is a timeseries from the Corning SchoolNet site with observations shown every 6 seconds for a period of only 15 minutes! The rapid wind shift and initial temperature drop take place within a minute. Temperatures continued dropping for the rest of the day on Sunday and now are below zero for many locations in Iowa.

Voting:
Good = 36
Bad = 7

Tags:   coldfront  

The featured chart is of air temperatures from the Des Moines airport from Monday evening to Tuesday evening. You can see the precipitous 50 degree drop in temperature over just 24 hours. Today will be another very cold day with highs around 10 with more chances of snow beginning this evening and lasting into the weekend. Our brutal winter continues!

Voting:
Good = 23
Bad = 2

Tags:   coldfront  

A dry line is a term used by meteorologists to describe a boundary between moist and very dry air masses, but it differs from a cold front such that temperatures are often as warm or warmer behind the boundary. These boundaries are common in places like Texas and Oklahoma, but are sometimes brought to Iowa by powerful storm systems like the one we experienced yesterday and often also spark severe weather. The featured image is from IEM Northeast Ames sensor showing the drop in dew point with the passage of the dry line.

Voting:
Good = 23
Bad = 16

Tags:   front  

A front staled out over Northeast Iowa on Sunday seperating distinct air masses for most of the day. The featured chart is a temperature comparison between Oelwien and Decorah, who are only seperated by 50 miles. Places further to the east even struggled to get out of the 40s, while most of Iowa was in the lower 80s. This boundary will lift further north today allowing places like Decorah to enjoy the 80s as well.

Voting:
Good = 22
Bad = 5

Tags:   front  

The featured time series is from the Worthington, MN KELO WeatherNet site, which is in SW Minnesota. The long advertised cold front has been waffling around over NW Iowa for the past 2 days, but is slowing making progress SE this morning. On the plot, it appears it went through Worthington shortly after 4 AM and has dropped its temperature by 17 degrees thus far. This pattern will be common for most of the Iowa today with even colder air then working into the state later today.

Voting:
Good = 23
Bad = 11

Tags:   front  

A strong warm front was bisecting the state yesterday. Depending on which side of the front you were, your Sunday was either hot and muggy or cool and damp. The front has shifted south a bit this morning.

Tags:   front  

A warm front made its way into Western Iowa on Monday. This resulted in an amazing contrast in temperatures. SW Iowa warmed almost to 80°F, while NE Iowa suffered with snow showers and much cooler temperatures.

Tags:   front