Severe Storm Outlook Narrative (AC)
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ACUS11 KWNS 151935
SPC MCD 151934

Mesoscale Discussion 2149
NWS Storm Prediction Center Norman OK
0134 PM CST Fri Nov 15 2019

Areas affected...Northern and western ME to the Champlain Valley

Concerning...Heavy snow

Valid 151934Z - 152300Z

SUMMARY...Snow squalls should push east-southeast from the Saint
Lawrence Valley, most likely across portions of northern and western
ME between 4 to 7 PM EST. A brief period of heavy snow with 0.5-1.0"
in 30 min is likely.

DISCUSSION...19Z surface analysis placed a cold front across the
Saint Lawrence Valley. Canadian radars in Montreal and Quebec City
have sampled a snow squall along the front. Somewhat enhanced
reflectivity was noted along the eastern portion of the squall near
Quebec City, which is consistent with a recent increase of
low-topped convective development/colder cloud tops in visible and
IR satellite imagery. Recent AMDAR data near Montreal sampled
inversion heights to 750 mb and near Quebec City to 700 mb. Latest
RAP/NAM guidance both are consistent with inversion heights further
deepening as the shortwave trough and attendant cooling aloft
approaches from southwest Quebec. Lack of stronger convergence along
the front, in addition to a modest surface rise/fall couplet
behind/ahead of the front, does suggest that squalls which progress
across the international border will probably subside within a
couple hours after sunset.

..Grams.. 11/15/2019

...Please see for graphic product...


LAT...LON   45347358 45757143 47606922 47386776 47036763 45686894
            44617101 44057257 43947341 44197411 44847428 45347358 is the U.S. government's official web portal to all federal, state and local government web resources and services.