758 FXUS61 KCAR 222230 AFDCAR Area Forecast Discussion National Weather Service Caribou ME 630 PM EDT Wed Sep 22 2021 .SYNOPSIS... High pressure will move slowly east of the region through Friday. A cold front will approach the region from the west late Friday and slowly move across the region into early Sunday. Low pressure over the Atlantic will move east of the region on Sunday. && .NEAR TERM /THROUGH THURSDAY/... 630 PM Update... Modified the pops a bit to account for the radar showing light showers/drizzle ending across the CAR CWA. An area of showers/drizzle was lifting up into srn Maine per the latest radar loop, but it appeared to be drying up as it high the high pres ridge axis in place. Rest of the forecast attm looks fine w/bringing in the hrly temps/dewpoints to match the current conditions. Previous Discussion... Area is btwn highly amplified ridge over the north Atlantic and upr low diving into the midwest this aftn. This is keeping nrn and western areas in low stratus, while Downeast areas cleared out for a time this aftn, enuf to rise into the mid 70s along with the St. John Vly. Central areas hv rmnd in the 60s/nr 70 as they remain socked in under low clds. Off and on light showers, more in the form of sprinkles hv fallen fm the low clouds and wl likely continue this evening but hv not included mention in the fcst as it wl likely be non-measurable and not widespread enuf. Tonight's fcst is similar to last night with low clouds and patchy fog expected acrs the area. Temps wl be similar to this morning with nw zones rmng in the 50s as entire region wl be under warm and humid airmass. With subtropical ridge still hvg a grip on the FA drg the day Thu conds wl be similar to tda with patchy fog and low clouds to start off the day and rmng over the region into the aftn. Upr low wl be lifting into the Great Lakes in the aftn with chcs for showers increasing twd the very end of the day tomorrow acrs the west. && .SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/... A very slow-moving weather maker is going to be the story through much of the short term forecast. Thurs Night expect a large upper level low at 500mb over the Great Lakes with ridging extending back over Eastern Maine. A vertically stacked low pressure system will be sitting over the Great Lakes. A cold front will extend southward into the Mid-Atlantic states. This will create a funnel to pump Atlantic moisture northward into New England. Expect a ton of low-level moisture so areas of fog are likely along the Downeast coast with patchy fog stretching north into the Highlands. Cannot rule out patchy drizzle along the coast and islands given the moisture. Otherwise, areawide the chance of showers will develop with this surge of moisture all throughout the low and mid-levels. Given the clouds, chance of showers and fog expect lows in the mid 50s north and near 60F from Bangor to the coast. Friday the front will push closer towards the FA as the 500mb trough tilts negatively over Quebec/Ontario. This will add in a push of Atlantic moisture over the CWA. Showers becomes a period of steady rain moving in from the west by as increased Low- Level jet develops with decent mixing. This means rain and breezy winds with some gusts 20-30mph especially at higher elevations. Timing looks like steady rain makes it into the western 1/2 of the FA by afternoon and eastern areas by sunset. Expect high temperatures in the upper 60s to low 70s but it will feel unusually muggy for late September. Light to moderate rain with perhaps pockets of heavy rain will push east with potentially some embedded thunder Fri evening. There will be patchy fog with the warm, moist air mass over the area. Temperatures will be in the mid 50s across the North Woods otherwise upper 50s to low 60s elsewhere. Models become interesting with some differences on the placement of the slow-moving front on Saturday. GFS 12z ops run seems to be the quickest pushing the front to eastern sections of the FA. While the ECMWF, Canadian and NAM keep steady rain going throughout the day. The 12z GFS has a period of dry weather and just low clouds Sat afternoon and evening but this seems to be the outlier. Expect a generally cloudy day with light to moderate rain likely. The ECMWF brings a new low up and along the front enhancing the rainfall Saturday afternoon into the long term period. The GFS has this similar scenario but holds off bringing it in till the long term on Sunday. Overall, took the national blend of models which results in likely to def POPs from Fri into Sat afternoon. In terms of rainfall we are looking at a decent shot of 1/2 to 1 inch of rain in the FA with the best chances of getting 1 inch or more along the Longfellow Mtns with orographic enhancement. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... Model disagreement continues Sat night into Sunday with uncertainty if we will be able to salvage one alright weekend day. 12z GFS/ECMWF both showing a very negatively tilted trough over the Northeast into Canada with an additional surge of moisture with associated sfc low pressure. GFS has this axis of rain tilting back over the FA while the ECMWF keeps the front pushing east putting the axis in New Brunswick. Once again with uncertainties in the members with the recent runs opted to take the blend. This results in likely POPs across the entire area Sunday AM lifting north turning into chance of showers through the afternoon from south to north. Basically it comes down to this weekend not looking so great for outdoor activities with the leaves changing colors. Winds will shift west as the front pushes into New Brunswick so with us on the east side of the trough expect highs in to the upper 60s to low 70s. Cooler air will be working into the North Woods with low to mid 60s expected. Pockets of sunshine will develop later in the day especially in southern half of the area. Mon-Tue this trough will become long wave and be over the area during this time frame. This will keep the pattern active with a front passing through Mon and energy aloft Tue. Partly Sunny skies with the best sunshine across the coastal zones with generally westerly winds. Highs will be warmer across southern areas thanks to downsloping so expect upper 60s to around 70F. Northwest of the Longfellow Mtns and into the Crown expect upper 50s to mid 60s with the coolest areas in the North Woods. Overnight lows will be in the mid to upper 40s north and low 50s south. Tue Night - Wed once again models are showing signs of a new shortwave somewhat looking like a winter time Alberta clipper. Placement of the energy and trough will determine how a low pressure develops over the warmer Gulf Stream waters. This will keep a chance of showers in the forecast but as of right now given the uncertainty not expect a total washout. Highs Wednesday look to be in the upper 50s to low 60s north with the troughing and cooler air aloft and mid 60s in southern coastal areas. && .AVIATION /00Z THURSDAY THROUGH MONDAY/... NEAR TERM: Mainly VFR expected this afternoon and evening. Brief MVFR cig may move through HUL, PQI and CAR this afternoon. Cigs lower to MVFR again for all terminals with the exception of BHB after midnight, before diminishing to IFR between 08z and 10z. Conditions improve to MVFR after 13z. BHB will be most likely to see VFR next 24 hours though confidence in this is low at this point. SHORT TERM: Fri...IFR/LIFR at BGR/BHB in the morning with low cigs, drizzle and fog. Elsewhere generally VFR. All sites become MVFR/IFR cigs with morning showers becoming steady rain from west to east. SE winds 10-20kts. Fri Night - Sat...IFR/LIFR with low cigs/vsby. Rain likely through the entire period. Patchy fog. SE winds 10-15kts becoming S 5-15kts. Sat Night - Sun...MVFR/IFR with low cigs/vsby. Patchy fog. Rain likely through Sun AM slowly tapering to showers from south to north in the afternoon. IFR/LIFR improves to MVFR/VFR in the afternoon. S winds 5-10kts shift W in the afternoon 5-15kts. Mon...VFR. A chance of showers. W-SW winds 5-15kts. && .MARINE... NEAR TERM: Winds and seas below SCA thresholds through Thursday. Patchy fog will lead to reduced visibilities tonight. SHORT TERM: Winds/seas generally below SCA through the period. Winds/seas may approach low end SCA criteria over the outer waters Fri into early Sat. Potential for wind gusts to 25kts and seas 4 to 5 feet. Seas will remain around 3 to 5 feet through Sun night. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...None. MARINE...None. && $$ Near Term...Farrar/Hewitt Short Term...Sinko Long Term...Sinko Aviation...Farrar/Hewitt/Sinko Marine...Farrar/Hewitt/Sinko