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Area Forecast Discussion (AFD)

Issued by Caribou, ME (CAR)

                            
000
FXUS61 KCAR 242204
AFDCAR

Area Forecast Discussion
National Weather Service Caribou ME
604 PM EDT Wed Apr 24 2019

.SYNOPSIS...
Low pressure will exit across Nova Scotia tonight. Weak high 
pressure will build over the area Thursday then another low
will approach from the southwest on Friday.
&&

.NEAR TERM /THROUGH THURSDAY/...
Update...
Surface/upper level low pressure will exit across the Maritimes
tonight, with high pressure starting to build toward the region
late. Expect rain, mixed with snow at times, across the north 
and mountains early tonight then tapering to isolated snow/rain
showers overnight with skies remaining mostly cloudy. Little or
no snow accumulation is expected. Across central and Downeast 
portions of the forecast area expect a chance of rain early 
tonight, with mostly/partly cloudy skies overnight. Low 
temperatures will range from the lower 30s north, to the mid 30s
Downeast. Have updated the forecast to adjust for current 
conditions along with overnight temperatures and clouds. 

Previous Discussion...
Drying out later tonight and remaining dry into Thursday as 
high pressure builds in. Northerly flow with fairly steep 
low/mid level lapse rates will allow a nice stratocumulus deck 
to form over the north, with mostly cloudy skies in the north 
and partly cloudy Downeast. Remaining cool with highs in the 40s
north and low to mid 50s Downeast.
&&

.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY NIGHT/...
A high pressure ridge across the area at the start of the period
will move east late Thursday evening. A low over Southern OH
northern KY will begin tracking northeast towards ME. The 
associated warm front will move into southwest ME mid morning 
Friday and spread to northern ME by early afternoon. Early 
Saturday morning the cold front will move into Southwest ME, 
with a secondary low along the front moving into the southwest 
portions of the Gulf of Maine. Saturday morning the this low 
track northeast into the Bar Harbor area. Saturday evening by 
the end of the period the front and secondary low have moved 
east of the area, the primary low will have track Gulf of St 
Lawrence keeping northern ME in wrap around precipitation into 
the early portions of the extended period. 

Loaded a blend of the GFS/NAM/ECMWF/GEM to smooth out the minor
differences in the models. Used NWPSCG1CAR for seas in the
coastal waters. Used GYX Wnd Gust tool for Gusts. Used consall
for QPF.
&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
A low pressure system over southern Washington County at the 
start of the period will move east into New Brunswick early 
Sunday morning. Higher pressure will ridge across the area. A 
low will track across the Gulf of Maine waters Sunday afternoon 
and evening bringing showers to the Downeast Coast. This low 
will track into the Bay of Fundy early Monday morning. The ridge
will remain across the state. Another low is expected to track 
through the Gulf of Maine Tuesday evening. By Wednesday 
afternoon the models are at odds on the movement of the next low
to affect Maine. The GFS bring the low into SW ME by Wednesday 
afternoon. The GEM and EC bring it into SW ME at the end of the 
period. 

Loaded a blend to smooth out the differences in the models,
however the solution leans more towards the ECMWF solution. Used
NAWAVE4 for seas in the coastal waters. Used windgust by factor
tool.
&&

.AVIATION /22Z WEDNESDAY THROUGH MONDAY/...
NEAR TERM: Generally expect MVFR to IFR conditions across the
region through much of tonight, improving to VFR very late 
tonight or early Thursday morning Downeast, with MVFR likely 
persisting in Northern Maine from KMLT and KHUL north for most 
of Thursday.

SHORT TERM: MVFR across northern Maine. VFR HUL and south.
Increasing clouds and decreasing ceilings becoming MVFR HUL and
south late morning Friday. Low MVFR to IFR conditions Friday
evening at all sites as a warm front moves across the area.
Becoming IFR to LIFR in heavier precipitation Friday evening.
Ceiling will begin to lift for BHB and BGR Saturday afternoon as
the cold front move through. MVFR conditions by late afternoon
Saturday. Northern Sites will remain in wrap around
precipitation through Sunday morning. IFR to Lower end MVFR in
showers for FVE, CAR, PQI, and HUL ceiling will break up Sunday
morning, all sites to VFR by Sunday afternoon.
&&

.MARINE...
NEAR TERM: Winds/seas are expected to remain below small craft
advisory levels tonight through Thursday. Visibilities could be
reduced in rain early tonight. 

SHORT TERM: Higher pressure across the waters at the start of
the period. Winds and seas will be below SCA criteria Friday
afternoon. winds and Seas will build Friday afternoon reaching
SCA criteria by Friday evening. An SCA will likely be required
Friday evening through Sunday morning.
&&

.HYDROLOGY...
River Flood Warning remains in effect for the Mattawamkeag 
River near Mattawamkeag. The Saint John and Fish Rivers near 
Fort Kent have fallen below flood stage. The Mattawamkeag River
is holding steady. Ice has pushed out of the headwaters of the 
St. John River. 

The Fish River chain of lakes will need monitoring through the 
next week at least, since water levels are rising and ice could 
be breaking up during this timeframe. Concerned about potential 
for flooding as the lakes are high, w/a situation possibly 
similar to last Spring.

A potentially large rain event in store Friday night into
Saturday. Most likely, this rain will be enough to keep rivers
and streams steady, but if the system turns out to be wetter
than expected, flooding problems could result especially on
streams.
&&

.CAR WATCHES/WARNINGS/ADVISORIES...
ME...None.
MARINE...None.

&&

$$

Near Term...Norcross/Foisy
Short Term...Norton
Long Term...Norton
Aviation...Norcross/Foisy/Norton
Marine...Norcross/Norton
Hydrology...Foisy