912 
FXUS61 KCAR 150545
AFDCAR

Area Forecast Discussion
National Weather Service Caribou ME
145 AM EDT Fri Apr 15 2022

.SYNOPSIS...
An occluded front will cross the area overnight and continue 
east across the Maritimes tomorrow. Low pressure will approach 
later Saturday, then cross the region Saturday night. Upper 
level low pressure will cross the region Sunday. High pressure 
will cross the region Monday. Another low will cross the region 
Tuesday.

&&

.NEAR TERM /THROUGH TODAY/...
145 am update...
Update to ingest temps and dwpts into fcst but no changes needed
to pop and wx grids.  

Prev Disc: A warm front is trying to lift north but at the 
surface there is cooler air that isn't being scoured out of the 
area. This is thanks to southerly flow right off the colder Gulf
of Maine and the air mass is a cold air damming for this time 
of year. This is noted in the inverted MSLP plot in the model 
guidance today. Light steady rain will push northeast into New 
Brunswick with a gap in between with showers. The occluded front
is going to push into Vermont and Quebec this evening with a 
weak wave of low pressure developing over the Gulf of Maine. 
This will bring quickly back the likely to categorical pops 
across the northern 2/3rd with chance to likely pops Downeast. 
By daybreak tomorrow morning the front will be pushing through 
the western zones bringing an end to precip from west to east. 
With the clouds, rain and flow off the Gulf of Maine expect lows
in the low 40s across southern zones and mid to upper 30s 
across the north. Rain totals generally less than 0.5 inch with 
perhaps the highest totals 0.5-0.6 inch in the North Woods on 
the "ripe" snowpack. In addition to the rain tonight with light 
southeast winds expect areas of fog to develop across the area. 
Cannot rule out some locally dense fog especially in areas that 
still have snowpack across the north. 

Winds shift W-SW behind the front and decent pocket of surface
ridging tries to push up over the area with modeled 850-250mb RH
values in the 25-35% range. This would suggest rapid clearing
with sunshine in the morning behind the cold front. Tomorrow
will feature an air mass that is much warmer with 925mb temps
+6C to +8C with light SW flow. This means highs in the upper 50s
to low 60s across southern areas including the Greater Bangor
area around 63F. In the north it will be a nice warm spring day
with highs in the mid to upper 50s. This will likely add to more
snowmelt and continued ice jam threat (see hydrology section
below). Another weak boundary will push into northern areas with
500mb vorticity max coming across that will kick off some
scattered showers and some increased cloud cover.

&&

.SHORT TERM /TONIGHT THROUGH SUNDAY/...
A cold front will approach northern Maine later Friday night. Expect 
mostly cloudy skies along with increasing rain shower chances across 
mostly northern areas Friday night. Across Downeast areas, expect 
increasing clouds along with a slight chance of showers late. The 
front slowly moves south across the region Saturday, approaching 
Downeast areas late. At the same time, low pressure will 
develop along the front across southern New England and begin to
track toward Maine. A steadier rain will develop across the 
region Saturday with the approach of the low. The surface low 
will track across Downeast areas early Saturday night, then exit
across the Maritimes late. Upper level low pressure will also 
approach, from the west, late. Rain will taper to showers later 
Saturday night. Across Downeast areas, precipitation will remain
in the form of rain. Temperatures aloft will cool across 
northern areas later Saturday night with the approach of the 
upper low. Cooling temperatures aloft...along with diurnal 
cooling...should allow precipitation across the north to mix 
with or change to snow later Saturday night. Dependent on the 
extent of remaining precipitation, light snow accumulations 
could occur. The upper low crosses the region Sunday, keeping 
unsettled conditions with a chance of showers. Snow showers or 
mixed rain/snow showers will occur across the north and 
mountains early Sunday. Otherwise, expect a chance of rain 
showers across the region. Expect near normal level temperatures
Saturday/Sunday.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
The upper level low exits across the Maritimes Sunday night, while 
high pressure approaches from the west. Expect decreasing clouds 
Sunday night. High pressure crosses the region Monday, with low 
pressure approaching from the west late. Expect mostly sunny skies 
Monday, then increasing clouds Monday night with a chance of rain 
late. A snow/rain mix is possible across northern areas. Low 
pressure will cross the region Tuesday, then exit across the 
Maritimes Tuesday night. Rain Tuesday, will taper to showers Tuesday 
night. Across the north and mountains, the precipitation should 
taper to snow showers. Upper level troffing will cross the region 
Wednesday. Expect mostly/partly cloudy skies Wednesday with a 
chance of rain showers, possibly mixed with snow showers across
the north and mountains early. Low pressure should approach 
Thursday, though the timing is uncertain. Expect near normal 
level temperatures Monday/Wednesday/Thursday, with below normal 
level temperatures Tuesday.

&&

.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
NEAR TERM: LIFR/ocnl VLIFR early this morning will give way
rapidly to to VFR by early morning over Downeast terminals with
northern terminals by early afternoon. VFR thru tonight with
LLWS picking up twd end of TAF time at BGR and BHB, but closer
to 06z over the north. 

SHORT TERM:
Friday night...VFR/MVFR north with a chance of rain showers. VFR 
Downeast with a slight chance of rain showers late. South/southwest 
winds around 10 knots.

Saturday...MVFR/IFR north. VFR/MVFR, then MVFR/IFR Downeast. 
Developing rain. Southwest winds around 10 knots, becoming 
variable.

Saturday night...MVFR/IFR, occasional LIFR. Rain tapering to 
snow/rain showers north, tapering to rain showers Downeast. Variable 
winds around 10 knots, becoming northwest.

Sunday...VFR/MVFR. A chance of rain showers. Possibly mixed with 
snow showers across the north and mountains early. Northwest winds 
10 to 20 knots with gusts up to 25 knots. 

Sunday night...Occasional MVFR possible across northern areas early. 
Otherwise, VFR. Northwest winds 10 to 15 knots with gusts up to 20 
knots.

Monday...VFR. Northwest winds 10 to 15 knots, becoming variable 5 to 
10 knots.

Monday night...VFR early. MVFR/IFR late. A chance of rain late, 
possibly mixed with snow across northern areas. Variable winds 5 to 
10 knots, becoming southeast/east 10 to 15 knots.

Tuesday...MVFR/IFR, occasional LIFR. Rain. A rain/snow mix possible 
early north. East/southeast winds 10 to 20 knots with gusts up to 25 
knots, becoming variable around 10 knots.

&&

.MARINE...
NEAR TERM: Winds are gusting to 25-30kts across the outer waters
this evening but will begin to fall below SCA conditions. Waves
will remain 4-5ft across the outer waters so extended the Small
Craft Advisory from this package update till 8am tomorrow. Wave
period is generally 6-7sec. Winds/waves fall below SCA after 8am
tomorrow. Intra-coastal waters remain below SCA tonight through
tomorrow.

SHORT TERM: Small craft advisory conditions Friday night into
Saturday night. Conditions below small craft advisory levels 
Sunday. Rain Saturday through Saturday night. A slight chance of
showers Sunday.

&&

.HYDROLOGY...
The threat of ice jams continues on the Saint John and Allagash
Rivers due to jamming over locations where ice is thicker or it
encounters islands and/or substantial bends in the river. There
remains an approx 9 mile jam between Dickey and St. Francis. 
There is an additional jam on the Allagash in town where ice 
cannot discharge into the St. John. There is another small jam 
that is causing minor flooding between Lille and Grand Isle 
mainly impacting farm fields at this time. 

The latest snow survey data from Monday and Tuesday indicates 
snow water equivalent of 5 to 9 inches and snow depth of 18 to 
29 inches from Winterville north through Allagash, indicating 
that there is still a significant amount of snow left to melt 
across the Saint John and Allagash River basins. Further south 
along Route 11, snow water equivalents were less than 5 inches 
with snow depths less than 15 inches. High temperatures will 
reach upper 40s to mid 50s for the next few days. Continued 
river level rises are likely and ice jams remain possible across
the Allagash and Saint John Rivers into this weekend. 
Precipitation will mainly fall in the form of rain through the 
weekend and be generally less than 0.5 inch total over the St. 
John Valley. Any additional rainfall will be falling into "ripe"
snowpack so the potential for accelerated snowmelt is possible.

&&

.CAR WATCHES/WARNINGS/ADVISORIES...
ME...None.
MARINE...Small Craft Advisory until 8 AM EDT this morning for ANZ050-
     051.

&&

$$

Near Term...Buster/Sinko
Short Term...Norcross
Long Term...Norcross
Aviation...Buster/Sinko/Norcross
Marine...Buster/Sinko/Norcross
Hydrology...