packfan98
Moderator
UK Met.
PROBABILISTIC HEAVY SNOW AND ICING DISCUSSION
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD
351 AM EST THU DEC 7 2017
VALID 12Z THU DEC 7 2017 - 12Z SUN DEC 10 2017
***SOUTHEAST U.S. TO THE MID-ATLANTIC REGION***
WAVES OF LOW PRESSURE FORMING AND RIDING ALONG A FRONTAL BOUNDARY
OVER THE NORTHERN GULF OF MEXICO WILL ADVECT MOISTURE INLAND
ACROSS THE SOUTHEAST STATES WELL TO THE NORTH OF THE FRONTAL
BOUNDARY. THIS WILL BE AHEAD OF A LONG WAVE TROUGH APPROACHING
FROM THE WEST. BOUNDARY LAYER TEMPERATURES WILL END UP BEING THE
COMPLICATING FACTOR IN THE SNOWFALL FORECAST. MOST MODELS ARE
INDICATING BOUNDARY LAYER TEMPERATURES SLIGHTLY ABOVE FREEZING ON
THE NORTHERN EDGE OF THE PRECIPITATION SHIELD. IF SNOWFALL RATES
ARE HIGH ENOUGH, THEY COULD BRIEFLY OVERCOME THE WARM GROUND
TEMPERATURES AND RESULT IN MINOR ACCUMULATIONS ON GRASSY AND
FORESTED SURFACES. AT THIS POINT, IT APPEARS AS THOUGH THE
HIGHEST PRECIPITATION RATES REMAIN CLOSER TO THE GULF COAST, AND
THUS LIMITING WIDESPREAD ACCUMULATING SNOW.
BL several degrees below freezing throughout the system here. Right now, there is a ton of dry air aloft in the boundary layer, and there is a warm nose. That is expected to be flipped when the system comes in. I expect virga when it rolls in early tomorrow, then it to fall more when the humidity rises.Guys. Look at your BL temps & 850. There are signs that things might not be so great, regardless of these "snow maps". Here is the WPC talk:
Throwing CHA some love now. Yay
GEFS way up FWIW.
A Winter Storm Warning seems like a little bit of stretch here considering almost everyone won't see anything over 1-2"That would be a 180 degree turn from their morning thoughts. Their morning disco didn't sound encouraging for any advisories or warnings, but again that was this morning, quite a bit has changed since then.