Area Forecast Discussion
Issued by NWS Caribou, ME-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
FXUS61 KCAR 281042
Area Forecast Discussion
National Weather Service Caribou ME
642 AM EDT SAT MAY 28 2016
A weak cold front will cross the region today with high pressure
building down from Canada tonight. A warm front will lift north
of the area on Sunday into Sunday night bringing showers to the
.NEAR TERM /THROUGH TONIGHT/...
640 AM Update: Kept areas of fog in longer especially across the
northern 1/2 of the CWA as obs showing dense fog. VSBYS have been
slowly coming up. Adjusted the Hrly temps to fit the latest
conditions as 50s holding just about everywhere. The coolest
areas have been down along the coast and across eastern Washington
County as temps dropped to around 50. Sunshine expected later on
will help to boost temps rather quickly.
Main challenge this term will be convection potential across the
downeast and coast this afternoon and fog.
A weak cold front will continue to slide s today and should be
across the coastal waters this evening. Convection that fired up
earlier has moved out of the downeast area and weakened. Areas of
fog are plaguing the region this morning w/the lowest vsbys across
the northern areas. Will keep an eye on the fog this morning as a
Dense Fog Advisory may be needed. Fog will lift and burn off later
this morning w/some sunshine returning. Clouds will hang on longer
across the northern tier thus keeping maxes down some. Across the
central and downeast areas, sunshine will allow temps to rise
quickly and readings are expected to shoot well into the 80s all
the way to the coast as the wind becomes offshore. Convective temp
will be easily hit. Dewpoints in this region will be in the mid
50s to around 60. Sounding data showed enough moisture available
from 850 to around 700 mbs to allow for TCU development. Decent
llvl convergence as shown by the NAM and HRRR along the boundary
and atmosphere destabilizes. SB/MU CAPES of 1000 joules are shown
in the downeast region. WBZ is about 9500 ft and pwats of 1.5+
inches. Definitely enough for tstms. Showalter index drops to -1
or so. It does not look like organized convection but some storms
could be strong enough to produce hail around 1/2 inch w/heavy
rainfall. Decided to keep 20-30% POPs in place. The NAM looks to
be overdone w/its dewpoints therefore overloading the llvls but it
has the right idea.
For tonight, convection should wind down this evening w/loss of
heating and lack of significant forcing. Areas of fog expected
once again especially across the downeast and coast as the winds
turn to the ene. High pres to the n will nose down into the region
allowing for some clearing especially across the northern areas.
This will allow for a cooldown. Min temps will be tricky as northern
areas will cool back into the upper 40s while central and downeast
see mid 50s. A warm front is forecast to lift northward overnight
with some showers breaking out ahead of the front by early Sunday
morning back across the western areas. Left out any mention of
tstms as the airmass looks to be stable especially in the llvls.
.SHORT TERM /SUNDAY THROUGH MONDAY/...
A warm front will move northeast across the region during Sunday
as an upper level ridge builds across the region. Expect some
showers with the passage of the warm front, mainly across
northern areas, especially the St. John Valley where went with
low end categorical pops (75-80%). Otherwise expect mainly cloudy
skies across the region. The combination of cloud cover and
southerly winds will hold temperatures in the mid to upper 60s,
but only around 60 along the immediate coast. Sunday night will
be mainly cloudy with the chance for showers, especially across
northern areas. Monday will see the chance for showers and
thunderstorms in advance of a short wave approaching from the
west. Have added the mention of heavy rainfall for Monday
corresponding to likely or higher pops, mainly across central and
downeast areas. Precipitable water values around 1.5 inches and
dew points in the lower 60s will support the potential for heavy
downpours. Have also added the mention of areas of fog for coastal
downeast with high dewpoint air and south winds off the gulf of
Maine. Showers and thunderstorms will begin to diminish by later
Monday afternoon with the passage of the short wave.
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
Monday night will see partly to mostly cloudy skies with only the
chance for a shower. Tuesday will see a secondary cold
front crossing the region. Expect the chance for showers and
afternoon thunderstorms, mainly across northern and central
areas. Will also have to watch for the possibility of a few
stronger storms with the passage of the short wave and secondary
cold front Tuesday. Wednesday and Thursday are shaping up as dry
days with temperatures a bit above seasonal levels for this time
of year. Another system will bring the next chance for rain by
.AVIATION /12Z SATURDAY THROUGH WEDNESDAY/...
NEAR TERM: IFR/LIFR mainly across the northern TAF sites this
morning w/fog and low clouds. KBGR and KBHB will flirt w/periods
of IFR this morning and fog. Conditions are forecast to improve to
VFR later this morning into the afternoon. The challenge will
along the coast near KBHB as conditions could hang on for IFR
longer. For tonight, expecting fog development later in the
evening which could bring conditions down to IFR/MVFR.
SHORT TERM: Expect vfr/mvfr conditions on Sunday in showers
across the northern terminals and mvfr cigs kbgr/kbhb. Expect
widespread mvfr in cigs and sct showers across the northern
terminals and widespread ifr/lifr in showers, areas of fog, and
low cigs kbgr/kbhb. Monday will see a continuation of widespread
mvfr conditions in showers and thunderstorms along with ifr in
areas of fog along the coast.
Mainly vfr on Tuesday along with sct showers and thunderstorms mainly
north. Vfr conditions expected Wednesday and Thursday as high
pressure builds in.
NEAR TERM: Expecting seas and winds to stay below SCA this term
w/winds around 10 kts and seas 2-3 ft. Fog will be nuisance for
the mariners with navigation this morning and again tonight.
SHORT TERM: Winds/seas will remain below sca levels through mid
week. Areas of fog will reduce visibilty to less than 1 nm at
times Sunday night through Monday in areas of fog.