National Weather Service (2024)

Area Forecast Discussion
Issued by NWS Portland, ME

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-- Discussion containing changed information from previous version are highlighted. --475FXUS61 KGYX 070301AFDGYXArea Forecast DiscussionNational Weather Service Gray ME1101 PM EDT Thu Jun 6 2024.SYNOPSIS...A cold front crosses the area tonight with some showers andpossibly some thunder, mainly in the mountains. An upper lowslowly approaches from the west tonight bringing more scatteredshowers Friday. The upper low lingers over New England intoearly next week keeping chances of showers in the forecast mostdays.&&.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
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1055 PM...This update scale back POPS a bit in S NH and alongthe coast of ME, at least regard SHRA, although DZ is noted inmuch of this area at this time. The bulk of the rain overnightwill be mainly over the northern zones, and will take much ofthe night to work through there, although amounts generallyremain 0.5" or less through this area, with only a fewhundredths further S. Temps are either at or a few degrees abovetheir forecast lows attm as well.805 PM...I`ve adjusted the timing of POPS a bit, pushing themlater by a couple hours this evening, as the line is tracking alittle slower. Also added DZ to coastal areas of NH and form thecoast to the ME foothills, as we are seeing that. The DZ willlikely end once the showers move in, but across it will lastthrough the evening.Previously...Impacts:*An isolated heavier shower or stronger thunderstorm is possible in Western New Hampshire tonight.Some brief light showers are crossing the area at the momentassociated with a shortwave. These will be tapering off headinginto the evening as they lose instability, however SPCmesoanalysis and forecast soundings show 300-500 J/kg of CAPE,so a rumble of thunder can`t be ruled out. The main show will betonight as an upper low and surface frontal boundary approachthe area. A healthy line of showers has already developed alongthis boundary and is currently in central New York. This won`treach the New Hampshire border until around 8 or 9 PM, and thatwill be right as instability is waning. That being said WesternNew Hampshire may have a chance to see a heavier shower and/orisolated strong thunderstorm as PWAT values are still up around1.75" and forecast soundings show warm cloud depth in the rangeof 12-13 kft. They should be moving right along, howeveranything that is initially slow or begins to train will have tobe watched for isolated flooding. Showers will come and go asvisible radar shows this is a narrow band that will be breakingdown further as it crosses our area. Toward the coast may notsee much at all as onshore flow has advected cool moist airinland, and in fact some areas are already beginning to fog in.This will persist through the night as well as patchy fogpossible for areas that see decent rain. Low temperatures willbe in the 50s across the north and coast and closer to 60through southern and interior zones.
-- End Changed Discussion --&&.SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY/...Impacts:* No significant weather impacts expectedFriday will start dry in many places behind the front, but thechance for scattered showers and an isolated thunderstorm willreturn later in the day as height falls generate a few hundredJ/kg of CAPE. Lack of synoptic forcing and persistent onshoreflow means the highest shower coverage will probably be north ofthe mountains. Anything that develops to the south will beconvective in nature and therefore more isolated, so have keptPoPs on the lower side to message that uncertainty in wherethose will develop. Lowest PoPs are along the coast where theaforementioned onshore flow will hinder instability. Otherwise,it will be a pleasant day with partly cloudy skies across muchof the area. High temperatures will range from the low 80s insouthern New Hampshire to low 70s north of the mountains. Thecoast will stay a bit cooler, in the 60s.Any showers that do develop will taper off quickly Friday nightas they lose their instability and low pressure looks like itwill finally be making its departure off to the northeast. Lowtemperatures will range from the upper 50s across the south tolow 50s through the interior and points north.&&.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...The overall pattern across the northeast in the extended willconsist of moist cyclonic flow due to upper level low pressurelingering across the northeast US and southeast Canada. Thiswill lead to unsettled weather at times. But at this time itdoes not look like there will be any washouts, just mainlychancy to low likely PoPs for showers and thunderstorms attimes, peaking in the afternoons with diurnal heating. This willbe mainly true Saturday through Monday before a period ofridging takes hold thereafter. Highest PoPs each day are in themountains, with lesser PoPs in southern NH where it could bedry most of the time.Temperatures each day will be in the 70s for most folks, with60s in the mountains. A warming trend will take place Tuesdayand Wednesday with highs returning back into the 80s.&&.AVIATION /03Z FRIDAY THROUGH TUESDAY/...Short Term...IFR conditions are expected along the coast asareas of fog develop tonight. KLEB and other western NewHampshire terminals may experience brief restrictions in heavyrain as a line of showers moves through tonight. Friday looksmainly VFR once overnight fog clears. There is a chance forisolated afternoon thunderstorms.Long Term...Outside of scattered showers and an isolatedthunderstorm, or two, ceilings will be mainly VFR throughTuesday. Winds also remain on the lighter side, generally lessthan 10 kt with westerly gusts possibly 20 to 25 KT Saturday andSunday afternoons.&&.MARINE...Short Term...Conditions hazardous to small craft are notexpected through Friday night. Dense marine fog is expected todevelop tonight. Seas will be in the 3-4ft range and winds willbe 10-15 kts with some gusts to 20 kts.Long Term...Conditions hazardous to small craft are notexpected through Tuesday. Seas will generally be 3-4 ft withwinds 10-15 kts with gusts to 20kts.&&.GYX WATCHES/WARNINGS/ADVISORIES...ME...None.NH...None.MARINE...None.&&$$SYNOPSIS...NEAR TERM...Baron/CempaSHORT TERM...BaronLONG TERM...EksterAVIATION...MARINE...