Area Forecast Discussion
Issued by NWS Caribou, ME

Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
-- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS61 KCAR 300146 AFDCAR Area Forecast Discussion National Weather Service Caribou ME 946 PM EDT Wed Mar 29 2017 .SYNOPSIS... High pressure will build down from Eastern Canada tonight and Thursday and crest over the area Thursday night...then move east Friday. Low pressure will track off the Mid-Atlantic coast Friday night and pass south of the Gulf of Maine on Saturday. && .NEAR TERM /THROUGH THURSDAY/...
-- Changed Discussion --
920 PM Update: Still some sct flurries and even isold sn shwrs with the upper trof axis slow to pivot Ewrd into new Brunswick. So we xtnded the mention of flurries into the late ngt mainly across Nrn and Ern ptns of the region. Also, we held on to a little more cldnss into the late ngt, delaying clrg ovr the Penobscot vly and Downeast areas about 2 to 3 hrs later then the prev update. Lastly, latest mid eve obsvd temps/dwpts were used to update fcst hrly values of each into the late ngt, with no sig chg in fcst lows xpctd at 6 to 7 am. Orgnl Disc: Any lingering snow showers across the area early this evening will dissipate as an upper level shortwave trough slides east into the Maritimes. High pressure will gradually build down from Eastern Canada tonight and Thursday. This will bring gradually clearing skies. Thursday will then be mostly sunny with afternoon temps just a couple degrees short of late March normals for the season. The gradient behind departing low pressure will bring a gusty northwesterly breeze on Thursday. Winds will diminish a bit late in the day as the gradient eases.
-- End Changed Discussion --
&& .SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/... A surface ridge of high pressure moving over the region, with an upper ridge moving in from the west, will act to bring mostly clear skies and calm winds to the CWA Thu night into Fri. Clouds will increase from west to east Fri aftn and eve as the next system approaches. This system manifests itself at the upper levels as a cut-off eating into and flattening out the ridge, with sfc low moving from the Ohio Valley across the Mid-Atlantic and then south of Long Island between Fri AM and Sat Am. Sig disagreement between NAM/ECMWF and GFS/CMC on the layout of the precip shield and POPs. The former shows an upr trof north of the cut-off, inducing more robust POPs to extend north of the sfc low thanks to a stronger mid-lvl - 700mb - trof north of the sfc low. The latter pairing both show the sfc low going further south, and don`t show a significant 500mb or 700mb trof north of the sfc low, keeping precip contained around the sfc feature and largely out of our CWA. The POPs and QPF were made to show a general lean toward the NAM/ECMWF solution, but don`t jump fully in with that pair in terms of the rather high POPs and QPF. POPs were generally capped at high-end likely, with storm total QPF generally 0.25-0.50 inches for central and Downeast areas. Temps expected to complicate snow totals, with many areas switching to rain, at least for a time, during the day Sat. Between the temps and track disagreement, definitely plenty of a chance for someone to get fooled on this system. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... Continuing with a lean toward the ECMWF from the short term, current forecast thinking is that any lingering precip departs quickly Sat night. The GFS, with delayed passage of an upr trof, would keep some light snow shwrs across the CWA into the day Sunday. Sun night into Tue AM look to be clear with sfc and upr ridging. Model disagreement returns mid-week with the reverse of the weekend scenario - the GFS takes a forecasted low further north, while the ECMWF keeps it to the south. For now, kept POPs pretty low given the disagreement. && .AVIATION /22Z WEDNESDAY THROUGH MONDAY/... NEAR TERM: MVFR conditions should improve to VFR Downeast this evening then VFR across the north late tonight. VFR conditions are expected across the area on Thursday. SHORT TERM: VFR conditions expected Thu night through Fri. Mid- lvl clouds move in Fri eve, with MVFR and IFR CIGs and vsbys sweeping in from west to east with arrival of snow Fri night. KPQI to KFVE may have a chance to keep higher vsbys and possibly higher CIGs depending on the track of the low pressure. Patchy MVFR and IFR cigs could linger Sat night with any lingering snow shwrs, but clearing to VFR for all places expected Sun into Mon. && .MARINE... NEAR TERM: A SCA will be up tonight through Thursday for gusty northwest winds gusting up to 30 kt across the offshore waters and 25 kt over the intracoastal waters as high pressure builds down from the north. SHORT TERM: Seas are expected to remain below SCA levels through the short term. Wind gusts will be borderline for offshore zones at the start of the period, but then decrease by Fri AM. Wind directions and speeds Fri night into Sat will be highly dependent on the track of the low pressure system. && .CAR WATCHES/WARNINGS/ADVISORIES... ME...None. MARINE...Small Craft Advisory until 8 PM EDT Thursday for ANZ050>052. && $$ Near Term...VJN Short Term...Kredensor Long Term...Kredensor Aviation...VJN/Kredensor Marine...VJN/Kredensor is the U.S. government's official web portal to all federal, state and local government web resources and services.