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When does central Iowa typically see its first snowfall?

We also looked at whether there's any link between the first snow and the rest of winter

When does central Iowa typically see its first snowfall?

We also looked at whether there's any link between the first snow and the rest of winter

RECOVERY. WELL, THE FORECAST IN IOWA IS PERKING UP SOME EARS AS IT DOES. IT HAPPENS ANYTIME THE WORD SNOW IS MENTIONED. I’M DOING THIS WHEN I HEAR THE WORD SNOW. I DON’T WANT TO HEAR IT. THERE’S A LOT THAT GOES INTO PREDICTING WHEN WE COULD SEE SNOWFALL. WE WANT TO BRING IN CHIEF METEOROLOGIST JASON SYDEJKO AND JASON. YOU SEE A LOT OF MODELS WHEN WORKING ON THE FORECAST. SOME COULD SHOW A LOT OF SNOW, BUT THOSE MODELS CAN CHANGE QUICKLY. THEY CAN THEY CAN ABSOLUTELY CHANGE ON A DIME. YOU CAN HAVE ONE MODEL RUN SHOW A LOT OF SNOW, EVEN A COUPLE FEET OF SNOW IN THE NEXT MODEL RUN JUST DOESN’T SHOW THAT, WHICH IS REALLY IMPORTANT TO KNOW WHERE YOU’RE GETTING YOUR INFORMATION FROM, BECAUSE THERE ARE A HOST OF SOCIAL MEDIA SITES THAT WILL JUST TRY AND SHARE SOME OF THIS INFORMATION TO GET NOTORIETY AND TO GET SHARES AND LIKES AND EXPOSURE AND SOME COMMON THINGS YOU SHOULD LOOK FOR ARE JUST REALLY EXTREME LANGUAGE. ANYBODY SAYING WE’RE GETTING A FOOT OR TWO DEADLY FLURRIES? I DON’T EVEN KNOW WHAT THOSE ARE. THEY USE WORDS LIKE KILLER BLIZZARD. THAT TYPE OF THING. SO THIS IS ONE MODEL RUN THAT WAS WIDELY SHARED ONLINE AND YOU CAN SEE IT PAINTS A BULL’S EYE OVER IOWA, ESPECIALLY NORTHEASTERN IOWA. THE PROBLEM IS THAT WAS ONE MODEL RUN. ALL OF THESE MODEL RUNS THAT HAVE UPDATED SINCE THEN AND JUST DON’T SHOW THAT HUGE AMOUNT OF SNOW THAT WAS SHARED ONLINE. SO KEEP IN MIND YOU REALLY NEED TO KNOW WHERE YOU’RE GETTING YOUR INFORMATION FROM. A LOT OF THESE PEOPLE ARE NOT METEOROLOGISTS AND WHAT WE LOOK FOR ARE THINGS LIKE THIS. THIS IS A CROSS SECTION OF THE ATMOSPHERE. YOU CAN SEE IN THIS PINK REGION. THAT’S WHERE THE SNOW GROWTH REGION IS. YOU LOOK FOR AREAS IN RED HERE THAT PROVIDE LIFT AND MOISTURE, AND THAT’S SOME OF THE THINGS WE LOOK FOR. IT’S KIND OF HARD TO DO THIS IN JUST A QUICK AMOUNT OF TIME, BUT ANOTHER THING WE LOOK FOR IS WHERE THIS AREA OF LOW PRESSURE IS HEADING. YOU CAN SHOW ONE MODEL RUN THAT SHOWS AN EXCESSIVE AMOUNT OF SNOW, BUT A SMALL DEVIATION IN THAT TRACK CAN MEAN HUGE DIFFERENCES IN WHAT WE WILL ACTUALLY SEE. SO AS WE MOVE INTO WINTER AND BEYOND, KEEP SOME THINGS IN MIND. KNOW WHO YOU’RE DEALING WITH AND KNOW THEIR CREDENTIALS. A LOT OF PEOPLE OUT THERE THAT AREN’T EVEN METEOROLOGISTS DON’T HAVE THE THE EDUCATION OR THE INFORMATION TO KNOW WHAT THEY’RE EVEN LOOKING AT AND LOOK FOR THOSE DRAMATIC WORDS. A LOT OF TIMES IT’S JUST NOT AS BAD AS THEY’RE SAYING. AND MAKE SURE YOU COMPARE SOURCES AS WELL. SO GUYS, I KNOW A LOT TO DIGEST HERE, BUT WE’RE HEADING INTO WINTER AND I’M ASSUMING WE’RE GOIN
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When does central Iowa typically see its first snowfall?

We also looked at whether there's any link between the first snow and the rest of winter

Each year, the cold winds of fall remind Iowans that snow will return eventually.Video above: Explaining winter weather misinformationWhen those first flakes appear varies quite a bit from season to season, though. Since records began in 1884, Des Moines' first measurable snowfall has happened anywhere from mid-October to late December. In 1932 and 2009, the ground first turned white on Oct. 10. In 1939, the capital city waited until Dec. 26 for any measurable snow. Nov. 14 has been the average first date for measurable snow in recent decades.Other Iowa citiesHere are the average dates of first measurable snow around Iowa:Mason City — Nov. 8Sioux City — Nov. 10Des Moines — Nov. 14Waterloo — Nov. 15Cedar Rapids — Nov. 15Council Bluffs — Nov. 17Davenport — Nov. 19Ottumwa — Nov. 21Does an early first snow mean a snowy winter?Interestingly, there might be somewhat of a relationship between how early/late our first snowfall is and how snowy that season ends up being. The chart above plots the Des Moines area's annual snowfall versus the date of first snow over the last 30 years. The trendline slicing through the chart shows that an early first snowfall appears to be at least loosely correlated with snowier years, and a late first snowfall is loosely correlated with less snowy years. If we make the same chart with all 100-plus years of records, the same trend appears — just not as clearly. It's an interesting little connection, but definitely not the determining factor in how snowy our winters are.

Each year, the cold winds of fall remind Iowans that snow will return eventually.

Video above: Explaining winter weather misinformation

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When those first flakes appear varies quite a bit from season to season, though.

Since records began in 1884, Des Moines' first measurable snowfall has happened anywhere from mid-October to late December.

In 1932 and 2009, the ground first turned white on Oct. 10.

In 1939, the capital city waited until Dec. 26 for any measurable snow.

iowa first snowfall
Hearst Owned
Average computed from 1991-2020. Data from MRCC/NOAA.

Nov. 14 has been the average first date for measurable snow in recent decades.

Other Iowa cities

Here are the average dates of first measurable snow around Iowa:

  • Mason City — Nov. 8
  • Sioux City — Nov. 10
  • Des Moines — Nov. 14
  • Waterloo — Nov. 15
  • Cedar Rapids — Nov. 15
  • Council Bluffs — Nov. 17
  • Davenport — Nov. 19
  • Ottumwa — Nov. 21

Does an early first snow mean a snowy winter?

Interestingly, there might be somewhat of a relationship between how early/late our first snowfall is and how snowy that season ends up being.

iowa snow statistics
Zane Satre
Chart created by author. Data from MRCC/NOAA.

The chart above plots the Des Moines area's annual snowfall versus the date of first snow over the last 30 years.

The trendline slicing through the chart shows that an early first snowfall appears to be at least loosely correlated with snowier years, and a late first snowfall is loosely correlated with less snowy years.

iowa snow statistics
Zane Satre
Chart created by author. Data from MRCC/NOAA.

If we make the same chart with all 100-plus years of records, the same trend appears — just not as clearly.

It's an interesting little connection, but definitely not the determining factor in how snowy our winters are.