12/24/12

Update 12/26 - Winter Storm Snow Amounts

Our first snowstorm of the Winter 2012-13 lived up to its expectations for the most part with a general 4 - 7" snowfall. As expected; areas over the far east had the most snow with some 8 - 10" falls while areas over far northwest (Midland and Bay counties) had little to none. 

Here's the snowfall map and specific amounts from our NWS spotters. Here in northern Livonia, I received 6.2" total with some foot drifts.

Snowfall totals from the December 26th, 2012, Winter Storm

Snowfall totals from the December 26th, 2012, Winter Storm
PUBLIC INFORMATION STATEMENT...STORM TOTALS
NATIONAL WEATHER SERVICE DETROIT/PONTIAC MI
1053 AM EST THU DEC 27 2012

THE NORTHWEST FLANK OF A SIGNIFICANT WINTER STORM IMPACTED POST 
HOLIDAY TRAVEL ACROSS SOUTHEASTERN MICHIGAN ON DECEMBER 26TH. 
WIDESPREAD SNOW LIFTED ACROSS THE MICHIGAN-OHIO STATELINE DURING THE 
LATE MORNING HOURS...ARRIVING OVER PORTIONS OF THE I 69 CORRIDOR 
DURING THE MID AFTERNOON. WHILE THE STORM SYSTEM TRACKED THROUGH THE 
TENNESSEE VALLEY TRANSFERRING ENERGY TO THE EAST COAST DURING THE 
AFTERNOON...AN AXIS OF ENHANCED MOISTURE BECAME ANCHORED OVER MUCH 
OF SOUTHEASTERN MICHIGAN THROUGHOUT THE EVENING. BY DAWNBREAK OF 
DECEMBER 27TH...A GENERAL 4 TO 7 INCHES OF SNOWFALL FELL SOUTHEAST 
OF A LINE FROM BAD AXE TO MANCHESTER...WITH AMOUNTS IN EXCESS OF 10 
INCHES COMMON FOR LOCATIONS IN EASTERN ST CLAIR AND SANILAC COUNTIES 
ADJACENT TO LAKE HURON.

STORM TOTAL SNOW REPORTS

LOCATION                  SNOWFALL     DURATION
                          (INCHES)      (HOURS)        LAT       LON

...BAY COUNTY...
   2 NE AUBURN             M   0.9           14     43.62N    84.05W

...GENESEE COUNTY...
   LINDEN                  M   3.0           14     42.82N    83.78W
   BURTON                  M   4.0           14     43.00N    83.62W
   GOODRICH                M   4.4           14     42.92N    83.51W
   FLINT                   M   5.0           14     43.02N    83.69W
   4 N BURTON              M   6.0           14     43.05N    83.62W

...HURON COUNTY...
   PORT HOPE               M   0.8           14     43.94N    82.72W
   5 NNW FILION            M   1.1           14     43.96N    83.04W
   PORT AUSTIN             M   2.0           14     44.04N    83.00W
   BAD AXE                 M   4.5           14     43.80N    83.00W

...LAPEER COUNTY...
   LUM                     M   4.5           14     43.10N    83.15W
   LAPEER                  M   4.6           14     43.05N    83.32W
   NORTH BRANCH            M   5.8           14     43.23N    83.19W

...LENAWEE COUNTY...
   MORENCI                 M   3.4           14     41.72N    84.22W
   TECUMSEH                M   3.4           14     42.01N    83.94W
   ADRIAN                  E   3.5           14     41.90N    84.04W
   2 WNW TIPTON            M   3.8           14     42.03N    84.10W
   1 SW BLISSFIELD         M   4.0           14     41.82N    83.88W

...LIVINGSTON COUNTY...
   HOWELL                  M   3.5           14     42.61N    83.94W

...MACOMB COUNTY...
   1 NNW UTICA             M   4.9           14     42.64N    83.03W
   SSE SHELBY TOWNSHIP     M   5.2           14     42.67N    83.03W
   4 NNW RICHMOND          M   7.7           14     42.86N    82.78W

...MONROE COUNTY...
   MONROE                  M   2.7           14     41.92N    83.39W
   MONROE                  M   2.8           14     41.92N    83.39W
   3 SW MONROE             M   3.8           14     41.89N    83.43W
   3 SW MONROE             M   3.8           14     41.89N    83.43W
   DUNDEE                  M   4.5           14     41.96N    83.66W

...OAKLAND COUNTY...
   WEST BLOOMFIELD         M   4.0           14     42.57N    83.38W
   2 SE ROYAL OAK          M   4.3           14     42.49N    83.13W
   HOLLY                   M   4.4           14     42.80N    83.62W
   2 SE HOLLY              M   4.5           14     42.78N    83.59W
   FARMINGTON              M   4.5           14     42.46N    83.38W
   BLOOMFIELD HILLS        M   6.0           14     42.58N    83.25W
   2 NW WATERFORD          M   6.2           14     42.68N    83.42W
   4 SW MILFORD            M   6.5           14     42.54N    83.66W
   5 ESE HOLLY             E   7.0           14     42.78N    83.53W
   CLARKSTON               M   7.0           14     42.74N    83.42W
   MADISON HEIGHTS         M   7.0           14     42.50N    83.10W
   WHITE LAKE              M   7.3           14     42.65N    83.50W
   3 S LAKEVILLE           M   7.8           14     42.78N    83.15W
   3 SW LAKE ORION         M   8.8           14     42.75N    83.29W

...SAGINAW COUNTY...
   5 S MERRILL             M   0.5           12     43.34N    84.34W
   2 E MERRILL             M   1.0           14     43.41N    84.30W
   SAGINAW                 M   1.5           14     43.42N    83.95W
   CHESANING               M   1.6           14     43.18N    84.12W

...SANILAC COUNTY...
   SANDUSKY                M   4.0           14     43.42N    82.83W
   MARLETTE                M   4.5           14     43.33N    83.08W
   CROSWELL                M   7.0           14     43.27N    82.62W
   LEXINGTON               E   7.0           14     43.27N    82.53W
   LEXINGTON               M   7.0           14     43.27N    82.53W

...SHIAWASSEE COUNTY...
   OWOSSO                  M   1.0           14     43.00N    84.18W
   2 NE CORUNNA            M   2.2           14     43.00N    84.09W
   DURAND                  M   3.0           14     42.91N    83.99W

...ST. CLAIR COUNTY...
   1 NNW YALE              M   6.5           14     43.14N    82.80W
   2 W ALGONAC             E   6.5           14     42.62N    82.57W
   MARINE CITY             E   7.0           14     42.71N    82.50W
   3 E RICHMOND            M   7.7           14     42.81N    82.70W
   2 W PORT HURON          M  11.1           14     42.99N    82.47W
   3 W LAKEPORT            M  14.0           14     43.12N    82.56W

...TUSCOLA COUNTY...
   CARO                    M   3.0           14     43.49N    83.40W
   VASSAR                  M   3.5           14     43.37N    83.58W

...WASHTENAW COUNTY...
   SALINE                  M   2.8           14     42.18N    83.78W
   1 W ANN ARBOR           M   5.5           14     42.28N    83.75W
   2 NNW ANN ARBOR         M   5.5           14     42.30N    83.75W
   MANCHESTER              M   5.6           14     42.15N    84.04W
   ANN ARBOR               M   5.8           14     42.28N    83.73W
   SE ANN ARBOR            M   6.0           14     42.28N    83.73W
   2 WNW ANN ARBOR         M   6.3           14     42.29N    83.77W
   SALEM                   M   6.4           14     42.41N    83.58W
   CHELSEA                 M   6.5           14     42.31N    84.02W
   ANN ARBOR               M   6.9           14     42.28N    83.73W

...WAYNE COUNTY...
   4 NE DEARBORN           M   3.5           14     42.35N    83.16W
   DEARBORN                M   3.5           14     42.31N    83.21W 
   N LIVONIA               M   6.2           14     42.40N    83.37W
   2 NNW LIVONIA           M   3.8           14     42.42N    83.39W
   NORTHVILLE              M   5.2           14     42.44N    83.49W
   GARDEN CITY             M   5.4           14     42.33N    83.33W
   ROMULUS                 M   6.2           14     42.22N    83.37W
   RIVERVIEW               M   6.3           14     42.17N    83.19W
   WYANDOTTE               M   6.3           14     42.21N    83.16W
   GROSSE POINTE FARMS     M   6.8           14     42.40N    82.89W

___________________________________________________________________________________

12/25/12
Just a quick update to tweak storm particulars as of Christmas night;

Timing of the storm; 
Not much Change
I look for snow to overspread Southeast Lower Michigan from south to north during the first half of Wednesday and continue into Wednesday Night.

Snowfall trend;
Heaviest snowfall (lowest visibilities and most accumulations) at this time looks to be from the mid afternoon into the evening hours...just a few hrs later.

Snowfall amounts;
Models are still a little variable on storm track and amounts. 

The forecast remains basically the same over much of Southeast Lower Michigan except the far west and northwest areas.

I feel with the dynamics and moisture available; snowfalls over much of the region should still range in the neighborhood of         4 - 7" (though I wouldn't rule out some isolated 8" amounts).  The heaviest snow will fall over the east and extreme southeast portions of Southeast Lower Michigan. Lighter amounts of snow of 2 - 4" will be seen over the areas further out to the west and northwest. Therefore; the lighter snows of 2 - 4" would include the counties of Bay, Midland, Saginaw, Shiawassee and Livingston...or basically areas west of US-23 and I-75 in those counties.


Other notable weather;
Wind. Stiff northeast winds will pick up to between 15 to 25 mph with gusts around 30 mph creating blowing and drifting snow as the day wears on. Some lake enhancement snow off of Lake Huron is possible but with relatively "mild" temperatures in the mid 20s to around 30, this shouldn't be a notable lake event.

_________________________________________________________________________________
12/24/12
As mentioned in my previous blog; the potential for a snowstorm for Wednesday into Wednesday night does look likely. From my previous blog;

"Latest indications are the storm will take shape over the eastern Texas; scoop up Gulf moisture and head northeast into the Ohio Valley. How close she comes to Southeast Lower Michigan will dictate the snowfall over the region."

The majority of our model runs now take a strong short-wave of energy in the jet stream, entering over the West Coast early Monday, and still track it east southeast into eastern Texas by Christmas morning. This is an ideal location for these winter storms to fire-up and is one of our preferred tracks /2/ this winter in the Winter Outlook. As you can see on the map below, the short-wave energy generally takes two routes over the eastern half of the U.S.; either from the eastern Texas/Gulf region northeast into the Ohio Valley, or up the East Coast. In this case, the storm is slated to track northeast across the Tennessee Valley and into the Northern Ohio Valley. The energy will then transfer from the northern Ohio Valley to the East Coast where a new storm center will form. 



_________________________________________________________________________________

Little has changed on the timing of the storm; 
I look for snow to overspread Southeast Lower Michigan from south to north during the first half of Wednesday and continue into the evening hours.

Snowfall trend;
 Heaviest snowfall (lowest visibilities and most accumulations) at this time looks to be during the afternoon hours of Wednesday. 

Snowfall amounts;
The European cousin model /Euro/ and our American counterpart /GFS/ are pretty much in agreement now with the timing and track of the storm as of the Sunday night /00z/ run. Note the snowfall maps below from the NAM and GFS (last two snowfall maps).

At this time; I feel with the dynamics and moisture available; a preliminary estimate this far out of in the neighborhood of 4"- 7" seems suitable across much of Southeast Lower Michigan. Of course; any later storm track deviation or intensity, snowfall totals expected will be noted and updated.

Other notable weather;
Wind. Stiff northeast winds will pick up to between 15 to 25 mph with gusts around 30 mph creating blowing and drifting snow as the day wears on. Some lake enhancement snow off of Lake Huron is possible but with relatively "mild" temperatures in the mid 20s to around 30, this shouldn't be a notable lake event.

Step by step map projections

1-Eastern Texas-Gulf Low forming Christmas morning; Note the mild, moisture laden air streaming north out  of the Gulf to feed the developing storm.



2- The low pressure and storm center continues to deepen in very favorable conditions over the Tennessee valley as she tracks northeast with the upper short-wave dynamics. Also note; the "horse-shoe" shaped high pressure engulfing the storm around it.  This is a classic pattern, seen many times as the colder, drier winds of the high pressure are drawn into the storm on stiff northeast winds across the Lower Lakes and Ohio Valley. Eventually this will also act as an atmospheric block or "wall" causing the low pressure to slide off more to the east northeast. The trough (dashed brown line) out ahead of the storm many times tells the path she's aiming for, and in this case eventually western Pennsylvania.

 


3- Our storm center has pushed into the southeast Ohio/West Virginia region as a new low is given birth on the East Coast Wednesday evening. Note the winds have gradually shifted to nearly due north over Southeast Lower Michigan, a sign the low is beginning to pull away to the east northeast and pressure rises will follow.




 Projected snowfall totals by the NAM and GFS by Wednesday night at Midnight from the Sunday evening runs.

Both models are fairly similar in extent and amounts but with the GFS a bit lower over Southeast Lower Michigan than the NAM. My vote at this time /Sun night/ would be toward the GFS.

                                                                         N A M


                                                                            GFS


As the time approaches, look for updates if needed.

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


Published 215am; Mon 12/24