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FXUS61 KCAR 180543

Area Forecast Discussion
National Weather Service Caribou ME
1243 AM EST Sun Feb 18 2018

Low pressure moving east of the mid atlantic region will bring 
some snow to the area overnight and Sunday morning, especially 
across down east areas. High pressure will build in Sunday 
afternoon and then move east of the coast on Monday with a 
milder flow of air to start the work week.


1245 am update...
1009mb sfc low located 150 miles southeast of the NY Bight wl
continue tracking northeast overnight twd area of greatest
pressure falls. Snow has overspread most of New England as of
05z with far northern and ern Maine yet to start snowing. Only
minor tweaks to current temps, grids and winds with this update.
Wl re-evaluate potential for possible headline expansion with 
next update.

Previous Discussion...
Snow will develop from west to east after midnight. As the mid 
atlantic low tracks east overnight, an inverted trof will extend
northwest of the low toward the mid coast of Maine. This will 
enhance the snowfall toward the coast, especially coastal 
Hancock county. Thus, will issue a Winter Weather advisory for 
coastal Hancock for 3 to 5 inches of snow beginning late tonight
through Sunday morning. The soundings do show some low level 
instability, as pointed out by the mid shift, and this could 
result in locally higher snow amounts. Will just need to monitor
the system as it evolves later tonight into Sunday morning to 
make any adjustments to snowfall amounts, as these type of 
systems can be difficult to forecast until they actually evolve.
Across the rest of down east Maine, including greater Bangor, 
generally expecting 2 to 3 inches by Sunday morning. Snow 
amounts will drop off across far northern Maine with only an 
inch or two expected.

Any morning snow Sunday will diminish by mid day, with skies
brightening in the afternoon as high pressure once again builds
toward the region. High temperatures on Sunday will actually be
above normal, with upper 20s to lower 30s north and mid to upper
30s down east.


Sun ngt will begin clr...with increasing cldnss initially across
the N as deep layer warm advcn begins with milder ovrngt lows. 
Cannot rule out a brief pd of very lgt snow across xtrm Nrn 
ptns of the Rgn erly Mon morn, otherwise, Mon will be mcldy N 
and ptly sunny Cntrl and Downeast wih a contd trend of milder hi

Lgt precip will move into the Rgn Mon ngt as a back door cold
front brings colder llvl air into Nrn ptns of the FA. This could
result in a pd of mixed precip across the N, spcly far Nrn areas
late Mon ngt into Tue morn particularly if the the colder ECMWF
model verifies, but to erly attm to say with enough certainty 
as to whether a wntr wx adv will be needed, since other 12z 
dtmnstc models do not bring as much cold air into Nrn areas. Hi 
temps Tue will vary from the upper 30s far N to lower 50s ovr 
interior Downeast areas which will likely break into very mild 
air by aftn. For now, we went with conservative with 6 hrly QPF 
amts on Tue until we get better agreement with tmg of heavier 
pulses of rnfl, but for the tm being, this does not look like a 
hvy rnfl event for any ptn of the FA, but we need to monitor 
later model runs.


The front should then begin movg nwrd again as a warm front by 
Tue aftn and cont movg newrd towards the Nrn Can Maritimes Tue 
ngt and Wed. This will likely result in slowly rising temps 
across the Nrn ptn of the FA Tue ngt alg with additional rnfl.

Aftn erly morn rn shwrs Wed, a break in precip will allow for a
potentially record breaking hi temps across the FA as the entire
Rgn looks to be in the warm sector until mid aftn when a strong
cold front will sweep the Rgn from QB prov accompanied by
another rnd of rn shwrs ending as sn shwrs Wed eve. Following 
the cold front, clrg skies is xpctd late Wed ngt with fair and 
seasonably cold thu and Thu thru Fri. Clds will be on the 
increase late Fri as another low pres system from the OH vly 
apchs from the SW with the potential of some sn breaking out 
late Fri ngt and contg into Sat as llvl Srly winds brings milder
air chgng sn to rn from S to N across the Rgn as far north as N
Cntrl ptns of the FA. Went with hi chc max PoPs with this 
event. Hi temps Sat will likely be at least a few deg warmer 
than Thu or Fri.


NEAR TERM: Nrn terminals MVFR for next 1-2 hrs before IFR snow
briefly moves in after 08z. FVE will likely remain MVFR thru 16z
Sun, with CAR, PQI and HUL becoming MVFR again after 12z. For
BGR and BHB expect IFR through 13z in the morning as snow will
impact areas as system moves south of the state. MVFR expected
after 15z before skies clear by 18z.

SHORT TERM: All sites initially VFR for Sun ngt and Mon then 
transitioning to MVFR Mon ngt and IFR Tue with cldnss and vsbys
with lgt precip. All sites remaining IFR Tue ngt in rn, rn 
shwrs, and patchy fog, transitioning to MVFR on Wed with aftn rn
shwrs and eve rn/sn shwrs and then back to VFR late Wed ngt and


NEAR TERM: Winds/seas will remain below small craft advisory 
thresholds through Sunday, although a few wind gusts to 25 kts 
are possible across the outer most waters later tonight through
early Sunday morning.

SHORT TO LONG TERM: Msly SCA wind and wv conditions will prevail
from Mon thru Wed eve, with no hdlns likely Sun/Sun ngt and Wed
ngt thru Thu. Went with a blend of WW3/NWPS guidance for fcst wv


ME...Winter Weather Advisory until 10 AM EST this morning for 



Near Term...Farrar/Hewitt

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