Scientific Forecaster Discussion
fxus61 kgyx 280115
Area forecast discussion
National Weather Service Gray ME
915 PM EDT Mon Mar 27 2017
low pressure will track across southern New England before
exiting the coast this evening. This disturbance will produce
rain and a light wintry mix across portions of the interior
through late today. A cold front will push through the region
Tuesday night resulting in upslope showers and a brisk northwesterly
flow Wednesday into thurday. A weak ridge will build into the
region on Thursday and remain through Friday. The next storm
will approach the region on Friday night bringing widespread
precipitation for late Friday into Saturday. The best chance of
showers will be across northern and mountain sections with
approach of the cold front.
Near term /until 6 am Tuesday morning/...
910 PM update: some patchy fog has formed so added patchy fog
for all of fa through most of the night as low levels remain
very moist. Input latest mesonet data and made minor temp based
tweaks. No other changes attm as forecast is on track.
555pm update: some lingering very light pcpn exiting to the
east as forecast. Input latest obs data and temperature forecast
looks good. No changes to previous forecast attm.
steadier precipitation is tapering from southwest to northeast
with passage of the shortwave impulse evident on GOES water
vapor imagery. At the surface...low pressure was centered over
southeast Massachusetts and will slide offshore during the next
few hours. The steadier mixed precipitation will linger across
the mountains...vicinity of the international border...next few
hours and will hold on to the current Winter Weather Advisory
headline there. Otherwise...steadier rain and mixed precipitation
over central Maine will exit that area over the next hour and
the advisory will be expired there. Overnight...mostly cloudy
with abundant low level moisture with some patchy drizzle and
fog. Low will be mainly in the lower and mid 30s with some upper
20s across the northern mountains.
Short term /6 am Tuesday morning through Tuesday night/...
onshore flow tomorrow and tomorrow night ahead of a northern
stream impulse and associated cold front. Highs mainly in the
40s in the onshore flow with a few 50 degree readings over
southern New Hampshire and Connecticut valley.
Long term /Wednesday through Monday/...
a short wave trough will move across the region on Wednesday as
low pressure departs to our southeast. Colder air will filter
into the region Wednesday and especially Wednesday night on
increasing northerly winds. Upslope snow showers should be
prevalent in the mountains both Wed and Wed night.
The next possible precipitation maker is agreed upon by most
deterministic models and ensembles to arrive Friday or Friday
night. However, significant differences in short wave/surface low
track exist which allows for spread in thermal profiles and quantitative precipitation forecast
coverage. At this time, it does appear that some accumulating
snow and and/or mixed precipitation will be possible later
Friday and Friday night, and perhaps into Saturday. However,
there is a chance that the bulk of the precipitation shield
gets suppressed to our south, leaving US dry or with just a
little light precip.
Aviation /01z Tuesday through Saturday/...
short term...IFR will likely persist through tonight in clouds
and areas of drizzle and fog...with some improvement to MVFR on
small craft conditions are likely Wednesday night Thursday as
northwesterly flow moves over the waters in the wake of the cold
frontal passage. Small crafts are once again possible over the
weekend depending on track and strength of low pressure.
short term...should see marginal small craft in all but Casco
Bay into tonight. Small craft seas should linger into Tuesday
outside the bays.
small craft conditions are likely Thursday as northwesterly
flow moves over the waters in the wake of the cold frontal