Saturday, April 29, 2017

Winter Storm Watch issued for areas west/north of Duluth for Sun eve-Mon eve (Preliminary snowfall map in this post) A shot at 60-70 degree temps next weekend!

/Issued 4:57 PM CDT, Saturday, April 29, 2017/

A variety of weather headlines cover portions of the upper Midwest, western High Plains and central Plains.  Source:  http://www.weather.gov/crh/
















Closer to home a winter storm watch has been issued for areas west and north of Duluth for Sunday evening through Monday evening.












Here's my preliminary snowfall map for the Sunday night-Monday night storm.  Locally higher amounts are certainly possible especially in the 4-6" zone.











Forecast storm track through Tuesday morning.  Source:  http://www.wpc.ncep.noaa.gov
















Tonight's low temperature forecast.  Source:  https://graphical.weather.gov





















Sunday's high temperature forecast.  Source:  https://graphical.weather.gov





















Storm timeline for the Twin Ports of Duluth and Superior

-Stays dry tonight and most of Sunday.  East/northeast wind will continue to increase with gusts of 20 to 30 mph developing on Sunday.  Lows tonight ranging from 31 to 34 degrees; Highs Sunday 40 to 45 degrees.

-A few showers of rain, snow or sleet are possible late Sunday afternoon into Sunday evening.  No travel problems expected.

-A more widespread band of precipitation is expected to arrive later Sunday night, and should continue into Monday morning -- Precipitation types will depend on the surface temperature which looks to be around 33 degrees, so anything from wet snow, sleet to rain is possible with snow most likely as the heavier bands of precipitation move through.

-Lingering snow or mixed precipitation is expected Monday afternoon through Monday night.

-Right now I'm going with a total snowfall of 2-4 inches in the Twin Ports with the higher amounts probably occurring on top of the hill (Higher elevation)

-Roads could turn snow or slush covered at times especially late Sunday night-Monday morning.

-Strong, gusty east to northeast winds Sunday night and Monday at 20 to 30 mph with gusts to 40 mph.

-Storm track trends:  There has been a slight shift to the west with the storm track through Monday morning but the surface low is still expected to stay S/SE of the Northland.  The temperatures aloft especially the 925mb temps will be very marginal for snow as they hover right around 0 to -1 to +1C while the 850mb temps cool enough to support frozen precipitation around -1 to -4C.  Note:  A scenario that could play out is for rain to start, a switch to snow, and then a switch back to rain or a mix, this appears most likely in eastern Minnesota and northwest Wisconsin while areas west/north of Duluth maintain enough cold air to keep the precipitation falling as snow.

Note:  Figured I would re post these snow stats for May 1st -- Right now the only record that looks to be broken is the daily snowfall record for May 1st of 1.6 inches, I think the other records are safe the way it looks now, although its possible will get a top 5 calendar day snowfall total for the month of May on Monday -- To break into the top 5 we would need 3.6 inches of snow on Monday which appears to be within reach.

Snowfall records could be broken at Duluth, Minnesota on Monday, May 1st!  See stats below.

*Heaviest snowfall total on May 1st:  1.6 inches set in 1970

*May 1st -- Only 2% of years from 1874-2016 have featured a snowfall >1.0 inch.  0% have had a snowfall >3" and >6".

*Snowiest May on record is 8.1 inches (1954) 

2nd snowiest 6.0 inches (1950)
3rd snowiest:  5.7 inches (1924)
4th snowiest:  5.5 inches (1902)
5th snowiest:  4.5 inches (2010)

*Heaviest calendar day snowfall total during the month of May is 5.5 inches which occurred on May 10th, 1902.

2nd heaviest:  5.0 inches May 8th, 1924
3rd heaviest:  4.4 inches May 7th, 2010
4th heaviest:  4.3 inches May 2nd, 1950
5th heaviest:  3.5 inches May 17th, 1968


Tim