Severe Storm Outlook Narrative (AC)
Issued by NWS
ACUS11 KWNS 130556
SPC MCD 130555
Mesoscale Discussion 0174
NWS Storm Prediction Center Norman OK
1155 PM CST Sun Feb 12 2017
Areas affected...portions of southern and eastern Maine
Valid 130555Z - 131200Z
SUMMARY...Heavy snowfall rates (1-2 inches per hour) are expected to
become more widespread during the overnight period across southern
and eastern portions of Maine.
DISCUSSION...Bombogenesis of a Nor`easter east of the New England
coast is underway as very rapid surface pressure falls occur during
the 06-12 UTC period as a low deepens from 992 mb to 980 mb. Very
strong but intensifying deep-layer upward vertical motion will
promote increasing snowfall rates across southern and eastern Maine.
The heaviest snowfall rates are forecast to coincide when mid-level
forcing maximizes after the end of the discussion period (12-18
UTC). Yet, snow to liquid equivalent ratios of at least 12:1 will
couple with the strengthening ascent and precipitable water and
yield snowfall rates ranging from near 1 inch per hour around 06 UTC
to 1-2 inches per hour primarily after 09 UTC.
...Please see www.spc.noaa.gov for graphic product...
LAT...LON 44967043 45976784 44716680 43517031 44967043