/Issued 4:43 PM CST, Sunday, January 7, 2018/
Latest thoughts for the midweek system
*One thing I’m not liking is the surface low which looks to weaken as it heads northeast out of the southern/central Plains; Also looks like a rather broad area of low pressure stretching southwest-northeast instead of just one main low pressure center, typically for a major event you’ll want just one main surface low.
*This system could have good dynamics though with strengthening upper level winds and a nice temperature gradient from NW-SE. Decent lift is also expected, but does it linger for several hours, or will it move along quickly? Still a few things to monitor as we move forward with future computer model runs during the next few days.
*Preliminary snowfall accumulation map for Wednesday night and Thursday*
-Euro model (00z & 12z runs) farther west/north with the snow area, with most of northeast Minnesota and northwest Wisconsin getting at least 2 to 5 inches of snow.
*Last few GFS and GEFS model runs have trended south/east with the axis of greatest snowfall, targeting areas from southern Minnesota to central Wisconsin with much lighter snowfall amounts in northeast Minnesota.
*My map below takes into account the model uncertainties, thus a rather large area is blanketed with 2 to 5 inch totals, if the GFS/GEFS models are correct, then I’ll need to trim the 2-5 inch area down quite a bit, especially on the west/north edge. If you want snow in Duluth, then you’ll want the Euro model to verify, if you don’t want much snow in Duluth, cheer for the GFS and GEFS models. More updates on Monday.
Last few GEFS model runs valid for late Thursday afternoon – Image below shows the amount of precipitation forecast through late Thursday afternoon, the trend has been for less precipitation (snowfall) for northern Minnesota with the midweek system per GEFS model with the corridor of heaviest precipitation amounts setting up farther south/east from southern Minnesota through central Wisconsin to upper Michigan.
Snowfall accumulation forecast ending Thursday evening per 12z GEFS model (Using a 10:1 ratio)
Note: Roughly 7/20 (Less than 50 percent) ensemble members have more than 2 inches of snow falling in Duluth on Thursday, all the other ones show around 2 inches or less than 2 inches of snow.
Temperature departure map for the week of December 31, 2017 — That is one cold looking map last week.
Precipitation departure map for the week of December 31, 2017 – A very dry week, not surprising when there is so much cold/dry air. Exception to this, downwind of the Great Lakes where lake effect snow continued to pile up at times last week.
Temperature and Precipitation report for Duluth, Minnesota
December 31-January 6, 2017-2018
High temperatures/Departure from Normal
12/31: -8 F/-27 degrees below normal
1/1: 2 F/-17 degrees below normal
1/2: 8 F/-11 degrees below normal
1/3: 0 F/-19 degrees below normal
1/4: 1 F/-18 degrees below normal
1/5: 1 F/-18 degrees below normal
1/6: 10 F/-9 degrees below normal
Low temperatures/Departure from Normal
12/31: -26 F/-29 degrees below normal
1/1: -19 F/-22 degrees below normal
1/2: -8 F/-11 degrees below normal
1/3: -11 F/-13 degrees below normal
1/4: -17 F/-19 degrees below normal
1/5: -20 F/-22 degrees below normal
1/6: -22 F/-24 degrees below normal
Note: Average temperature for the week of December 31, 2017: -7.8 degrees (-18.4 degrees below normal) Source: http://www.dnr.state.mn.us
Total precipitation: 0.02 inches
Normal: 0.26 inches
Departure: -0.24 inches below normal
State Average for Minnesota for the week of December 31, 2017
Average temperature: -8.0 degrees
Departure: -19.8 degrees below normal
Total precipitation: 0.02 inches
Departure: -0.18 inches below normal
*18 subzero nights in a row at International Falls, Minnesota (December 20-January 6) This streak ended Sunday morning, January 7 as the low temperature remained above zero! Of those 18 nights, 13 of them had a low temperature of -20 F or colder; 6 of them had a low temperature of -30 F or colder.
*14 subzero nights in a row at Duluth, Minnesota (December 24-January 6) This streak ended Sunday morning, January 7 as the low temperature remained above zero! Of those 14 nights, 6 of them had a low temperature of -20 F or colder.
*High of 25 degrees (so far) at the Duluth Airport today, January 7 — Warmest high temperature since December 19 (32 degrees)
*Since December 8, 2017 — Minnesota has reported the coldest temperature in the nation on 13 dates. Source: http://blog-weathertalk.extension.umn.edu/
*Over the 11 days since December 25, temperatures in Minneapolis have been subzero on 10 nights which has only happened one other time in history, December 25, 1886 to January 4, 1887. Source: http://blog-weathertalk.extension.umn.edu/
Mostly cloudy skies were common today across northern Minnesota while farther south skies were partly to mostly sunny with a trend to cloudier skies occurring this afternoon. Highs today were in the 20s to around 30 degrees, the warmest temperatures we’ve seen since December 19!
Tonight: Low pressure will move east out of Manitoba Province while a cold front moves south/east through the Northland. Areas of light snow and sleet will continue over parts of the Northland this evening so use caution if you have travel plans as slick spots could develop on road surfaces. It will be a mild night compared to how cold it’s been the past few weeks, lows tonight will only drop into the teens and 20s.
Monday: High pressure builds southeast out of the northern Plains behind tonight’s cold frontal passage. Mostly cloudy to partly sunny skies are expected Monday with a few flurries possible. Our mini thaw will continue with highs in the 20s to around 30 degrees. Lows Monday night will be in the single digits and teens.
Tuesday: High pressure moves off to the east with a southerly flow returning to the upper Midwest. Could see some patchy freezing drizzle begin to develop by Tuesday night over parts of the Northland as the atmosphere moistens up. Highs Tuesday will be in the 20s and 30s.
Forecast for Duluth and Superior
.Tonight… A few snow or sleet showers mainly this evening. Mostly cloudy. Low 20 to 25. Wind west to southwest at 10 to 20 mph.
.Monday… Partly to mostly cloudy. High 25 to 30. Wind northwest at 10 to 20 mph.
.Tuesday… Partly to mostly cloudy. High 27 to 32. Wind east to southeast at 5 to 15 mph.
Normal temperatures for Monday
Sunrise Monday: 7:53 AM CST
Sunset Monday: 4:39 PM CST