WINTER STORM WARNING has been issued for several counties

The other shoe has dropped and the snowfall rates of 1-1½" per hour that the models were predicting the other day now appear to be manifesting themselves. As such, NWS Detroit has upgraded a swath of counties, in a diagonal from Berrien to Sanilac, to a Winter Storm Warning, for snowfall totals of 6-10" expected in the warned areas. The Storm Prediction Center has also issued a mesoscale discussion regarding heavy snow for our area. This doesn't happen except for particularly strong winter storms. 

Text of the MCD is as follows:

   MESOSCALE DISCUSSION 1991
   NWS STORM PREDICTION CENTER NORMAN OK
   0836 AM CST SAT NOV 21 2015

   AREAS AFFECTED...PORTIONS OF NRN INDIANA...SRN LOWER MI...NWRN OH

   CONCERNING...HEAVY SNOW 

   VALID 211436Z - 211930Z

   SUMMARY...SNOW WITH RATES OF 1.0-1.5 INCHES PER HOUR WILL SPREAD
   ACROSS PARTS OF THE LOWER GREAT LAKES REGION INTO THE AFTERNOON
   HOURS.

   DISCUSSION...WATER VAPOR IMAGERY INDICATES A SHORTWAVE TROUGH
   CROSSING PARTS OF THE MID-MS VALLEY REGION. PRECEDING ISENTROPIC
   ASCENT AND DCVA CONTINUE TO FOSTER WIDESPREAD PRECIPITATION FROM SRN
   WI TO SRN LOWER MI SWD ACROSS THE MID-MS VALLEY. AS THE TROUGH
   CONTINUES ITS ENEWD PROGRESSION...PRECIPITATION WILL SPREAD
   EWD/ENEWD ACROSS THE DISCUSSION AREA. DEEP SUBFREEZING AIR IS
   ALREADY IN PLACE ACROSS MUCH OF THE MCD AREA -- SAMPLED BY THE 12Z
   DTX RAOB AND INDICATED BY MODEL SOUNDINGS. THIS WILL SUPPORT
   SNOW...WITH A BAND OF HEAVY SNOW LIKELY TO SPREAD ENEWD ACROSS THE
   MCD AREA IN CONCERT WITH A ZONE OF ENHANCED 700-MB FRONTOGENESIS
   ACCOMPANYING THE SHORTWAVE TROUGH. SFC OBSERVATIONS UPSTREAM ACROSS
   NRN IL...INCLUDING THE CHICAGO AREA...INDICATE HEAVY SNOW
   ONGOING...WHICH WILL CONTINUE SPREADING ENEWD AS PREVIOUSLY
   MENTIONED. SNOWFALL RATES OF 1.0-1.5 INCHES PER HOUR WILL BE LIKELY
   INTO THE AFTERNOON HOURS...WITH LOCALLY HIGHER RATES POSSIBLE. THE
   LEADING EDGE OF THE HEAVIEST SNOW WILL LIKELY REACH SERN LOWER MI
   AND NWRN OH LATER IN THE AFTERNOON -- PRIMARILY AFTER 20Z.

Text of the warning is as follows:  

...PERIODS OF HEAVY SNOW EXPECTED TODAY...

MIZ055-060>063-068>070-075-212215-
/O.UPG.KDTX.WW.Y.0009.000000T0000Z-151122T0200Z/
/O.NEW.KDTX.WS.W.0002.151121T1402Z-151122T0300Z/
SANILAC-SHIAWASSEE-GENESEE-LAPEER-ST. CLAIR-LIVINGSTON-OAKLAND-
MACOMB-WASHTENAW-
INCLUDING THE CITIES OF...SANDUSKY...OWOSSO...FLINT...LAPEER...
PORT HURON...HOWELL...PONTIAC...WARREN...ANN ARBOR
902 AM EST SAT NOV 21 2015

...WINTER STORM WARNING IN EFFECT UNTIL 10 PM EST THIS EVENING...

THE NATIONAL WEATHER SERVICE IN DETROIT/PONTIAC HAS ISSUED A
WINTER STORM WARNING...WHICH IS IN EFFECT UNTIL 10 PM EST THIS
EVENING. THE WINTER WEATHER ADVISORY IS NO LONGER IN EFFECT.

HAZARDOUS WEATHER...

 * SNOW WILL INCREASE IN COVERAGE AND INTENSITY THIS MORNING AND
   PERSIST THROUGH THE AFTERNOON INTO THE EARLY EVENING HOURS.
   SNOW WILL LIKELY BECOME HEAVY AT TIMES.

 * TOTAL SNOWFALL ACCUMULATIONS WILL RANGE FROM 6 TO 10 INCHES
   WITH HIGHEST ACCUMULATIONS ON GRASSY AREAS. SNOW WILL BEGIN TO
   ACCUMULATE MORE EFFICIENTLY ON ROADWAYS AFTER 4 PM.

 * THE SNOW WILL DIMINISH BY MID EVENING. HOWEVER...TEMPERATURES
   WILL FALL BELOW FREEZING...CAUSING INCREASINGLY SLICK ROADS.

IMPACTS...

 * TRAVEL WILL BE ADVERSELY AFFECTED...ESPECIALLY THIS AFTERNOON
   AND EVENING.

 * THERE IS A CHANCE FOR A PERIOD OF HEAVY WET SNOW ACCUMULATION
   WHICH MAY BE ABLE TO BRING DOWN SMALL TREE LIMBS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

 * A WINTER STORM WARNING MEANS SIGNIFICANT AMOUNTS OF SNOW ARE
   EXPECTED OR OCCURRING. THIS WILL MAKE TRAVEL VERY HAZARDOUS.

So far, only flurries are starting to fall in Pigeon within Huron County, which is still within the advisory zone. Light dusting is beginning to appear on area rooftops. I will be snapping pictures as the situation develops and sharing them with everyone.