Update 1/23/15 - Parade of Clippers Only Systems Bringing Snow This Slow Season

-Update 1/23/15

Latest model information has been weakening the low pressure to move through the Ohio Valley on Sunday or drifting it further south. Therefore; only the southern third of Southeast Lower Michigan will see snow on Sunday and generally just an inch or two.


Virtually all the snow received this paltry winter storm season over Southeast Lower Michigan has been the result of some Alberta Clipper type low pressure system. True; some impressive lake effect snows have resulted with the cold Arctic air sweeping over the Great Lakes but that's been local effects downwind of the Great Lakes, leaving only light amounts here.

Recent light snows this past few weeks have "nickled and dimed" the region enough to bring normal to even above normal snows to Southeast Lower Michigan for January...and we aren't done yet. The entire region is below normal for the winter but probably surprisingly, not that much. The prolific snow making month of November (and now January) helped out there with above normal snows. On average; the region has averaged just 2" - 6" below the normal snowfall expected thru this midwinter season. The main reason it seems like we've had less snow is that we haven't had any big snows (big meaning 6" or more) AND it was so snowy last winter. This winter's snow accumulation thus far is a far, far cry from last winter's when record snows were measured in most areas from the I-69 region (Flint to Port Huron) south across the Ann Arbor and Metro Detroit areas to the Ohio border!

As of the 22nd; 17 1/2 inches of snow /17.4"/ has been recorded at Detroit Metro Airport this snow season; 2.8" below normal  Flint has received more with 22 1/2 inches /22.5"/ but is still below its normal by 1.6". Further north around the Saginaw Valley, less snow has fallen this season with just 14.3", about 6" below normal.

Stronger Clipper This Weekend May Bring Better Snows Southeast Lower Michigan

Early but consecutive guidance on another upcoming Clipper Low Pressure system is that it will affect the area later this weekend. The low and storm center advances quickly southeast across the Upper Midwest and into the northern Ohio Valley, Sunday and Sunday night. Most guidance has been stronger with this system than the past several that affected the area - along with a bit better moisture supply. The devil is in the details as far as exact track and pressure differences with ensemble GFS members quite variable with both. Though, I would not be surprised if this system, like the last, tracks further north than the map below depicts and thus, it is used for a median track.

As this early time frame /Thursday evening/; look for the storm to bring a swath of light to moderate snowfall across Southeast Lower Michigan on Sunday. How much snowfall will depend on the exact track of the system. Clippers as a rule contain sharp lines of demarcation between snow and no snow on the southern extent of their track. Meaning; if the low tracks further north than the maps suggest below, less snow will fall particularly over extreme Southeast Lower Michigan...closest to the track. On the other side of this envisioned storm track; if she were to track further south then the Saginaw valley and other areas north would receive less snow. I'll fine tune the track into the weekend in updates but as it stands now; 2"-4" of snow is likely with even a higher core amount of 3"-5" possible. Again this is preliminary from what I'm seeing at this time but plan accordingly as this system has the potential to be weaker...or stronger at this early date.

Making weather fun while we all learn,
Bill Deedler -SEMI_WeatherHistorian

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