Winter Storm Watch 2/11

This year has been a nice change for snow lovers. We still have snow on the ground in Otsego, though it is glacier-like in composition due to the freezing and thawing temperatures.  We are now looking at a system coming in for tomorrow and another for the weekend, bringing in some meaningful snow.

Areas north of Muskegon and Big Rapids, including the Ludington area, may see a half-inch to 2-inch snow this morning, with little expected elsewhere. Then, several inches of snow is a fair bet between Wednesday afternoon and Thursday morning for much of Western and Mid Michigan.

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Winter Storm Watch

...WINTER STORM WATCH REMAINS IN EFFECT FROM WEDNESDAY AFTERNOON
THROUGH THURSDAY MORNING...

* WHAT...Heavy snow possible. Total snow accumulations between 5 and
  8 inches possible.

* WHERE...Portions of central, south central, southwest, and west
  central Michigan.

* WHEN...From Wednesday afternoon through Thursday morning.

* IMPACTS...Travel could be very difficult. The hazardous conditions
  could impact the Wednesday evening and Thursday morning commutes.

 

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Weather History

1899: Muskegon records their all-time record low of 30 below zero. Grand Rapids falls to 21 below and Lansing 22 below.

1999: A surge of warm air ahead of a cold front brings all-time record-high February temperatures to much of Lower Michigan. February records include 67 degrees at Muskegon and 69 degrees at both Grand Rapids and Lansing. Battle Creek hits 72 degrees.

On February 11, 1999, the temperature rose to 70 degrees in Detroit. This is the earliest 70 degree day ever recorded in the city of Detroit.

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Forecast Discussion

- Light Snow This Morning

Light radar returns are ongoing across the northwest portion of the
CWA area with light snow continuing through the morning. This all is
driven by a weak 700mb wave and a decaying arctic front crossing the
CWA aided by some lake enhancement. Additional snow of up to 2
inches is expected before ridging arriving this afternoon leads to
snow showers tapering off.

- Widespread 4-7" Snowfall With Areas up to 12" Possible
  Wednesday into Thursday

Bottom Line Up Front, have expanded the Winter Storm Watch into
Calhoun and Jackson Counties to account for the southeasterly trend
in the latest guidance.

The synoptic pattern driving this event is the ejection of a mid-
level wave into the region inducing cyclogenesis across the Ohio
Valley. The low then tracks into northwest/north-central Ohio which
synoptically places us in line with the best frontogenetical
forcing. Overall thinking remains the same that widespread 4-7 inch
snowfall is expected with a FGEN driven band of 7-12 inches is
likely to develop, favored south of a Mount Pleasant to Grand Rapids
line. The snow will start during the day Wednesday, peaking the
first part of Wednesday night as the best frontogenetical forcing
takes hold with rates of up to 1"/hr likely. The low then pulls
away late Wednesday night with a transition to light lake effect
snow during the day on Thursday.

One consideration that will need to be watched is mixed
precipitation across the southeastern forecast area. With the
southeastern shift in guidance, the warm nose aloft look to stay out
of the CWA keeping snow as the dominant type across the region
(albeit with only 10-13:1 ratios given a deep sub-DGZ isothermal
layer). The favoring of snow over ice across Jackson and Calhoun
Counties warrants expanding the watch given high QPF of 0.4-0.6" and
our expected SLRs. However, there is a minority of guidance, mainly
the RAP, that does bring in a brief period of warm air and
subsequent mixing with sleet and freezing rain. Further
refinements to the forecast are likely as the exact strength and
path of the low is determined. So some adjustments in snow
amounts, placement, and p-type are possible in subsequent
packages.

- Snow Expected This Weekend

After a brief respite Friday due to surface and upper-level ridging,
snow returns Friday Night into early next week. Similar to the mid-
week system we see a mid-level wave induce cyclogenesis across the
Midwestern US, followed by a period of lake effect as 850mb temps
fall into the -20s C. Long range ensemble forecasts shows QPF values
are likely to exceed 0.25" (60-80%) which brings the potential for
several inches of accumulating snow to the region for the Friday
Night/Saturday system thanks to mid-level FGEN. That is then
followed by additional snowfall Sunday into Monday in the form of
lake effect. Trends will need to be monitored for this timeframe
given the potential for travel impacts.