Saturday’s late April storm system is still on track to bring a mixed bag of rain and snow to southern Minnesota. But there are huge model differences on how much, if any, snow will accumulate in the Twin Cities.
My read of this inbound system remains the same as a few days ago. Conditions favor mostly rain for the Twin Cities with a few snowflakes mixed in, and little or no snowfall accumulation for most of the Twin Cities.
This low-pressure system tracks from Nebraska through Iowa Saturday. It will get stronger as it moves east. I’m inclined to agree with the Canadian model’s interpretation. A mix of rain and snow across southern Minnesota with the best chance for accumulating snow staying south of the Twin Cities.
Major model spread
It’s interesting, and a little frustrating, to see such a big model spread with this system. The European and Canadian models, along with the National Oceanic and Atmospheric Administration’s Global Forecast System model, agree with a mostly rain scenario for the Twin Cities.
The last several runs from NOAA’s North American Mesoscale Forecast System model have been hitting the notion of significant snowfall for the Twin Cities hard. But the NAM is the outlier. And it’s shifting south.
Sticking to my guns on Saturday's snow potential for MSP: Big model spread. NAM projects several inches for MSP. GFS/Canadian/Euro=mostly rain for MSP. I'm still favoring mostly rain with little/no snow accumulation for MSP. Few slushy inches SE MN, NE IA & WI. We'll see! #mnwx pic.twitter.com/Lw8R4Jogzw
— MPR Weather (@MPRweather) April 26, 2019
Here’s Friday morning’s 12z NAM 3 km model for 9 am Saturday. See how it brings heavy snow right up to the Twin Cities?
Now, look at the latest Friday afternoon 18z run. See the shift south, keeping most of the snow south of the Twin Cities?
That’s yet another trend line that suggests little if any snowfall accumulation for the Twin Cities.
Euro: All rain
Like the GFS and Canadian models, the usually trusty European Centre for Medium-Range Weather Forecasts model suggests mostly rain for the Twin Cities Saturday.
Southern Minnesota: A few slushy inches
The best chance for accumulating snow to my eye lays out across southern Minnesota, northeast Iowa, and southern Wisconsin.
I still think the NAM model solutions are overdone on snowfall. And indeed the latest NAM run has dialed back. A couple to a few slushy inches are likely across most of southern Minnesota. The best chance for significant snow runs from Rochester, Minn., and Decorah, Iowa, through Madison, Janesville, Milwaukee in Wisconsin and the northern suburbs of Chicago.
This is one of those rare occasions when I don’t sync with current National Weather Service advisories. I have an honestly different interpretation of the forecast from the amazing staff at our local NWS office.
I won’t be surprised to see the current coverage of advisories dialed back by Saturday morning.
I’ll keep the egg scraper handy just in case.
Milder next week
Our weather stays cool into early next week. But temperatures rebound again through the 60s late next week.
Spring resumes next week.