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. --506FXUS61 KGYX 281347AFDGYXArea Forecast DiscussionNational Weather Service Gray ME947 AM EDT Sun Jul 28 2024.SYNOPSIS...High pressure will continue fair weather over the regiontoday. An upper low tracks northwestward into New Englandtonight into Monday will initiate a period of unsettledconditions as additional troughs of low pressure approach fromthe west. Temperatures and humidity will be on the increaseafter Monday while chances for showers and thunderstorms mostdays will help limit high temperatures to the 80s.&&.NEAR TERM /UNTIL 6 PM THIS EVENING/...
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945am Update...No big changes in thinking for the forecasttoday. Sunny start, will begin to see some cu pop up through theafternoon as well as incoming plume of high to mid level cloudfrom the Gulf. Fog off in the coastal waters hasn`t materializedso far, but there are some ribbons near the outer waters ofPenobscot Bay. Smoke still very apparent on morning satelliteacross the area. Bumped temps down a couple degrees in the northwhere HRRR/RAP smoke models depict it to be denser aloft, aswell as added mention of haze for the higher summits. Stillgrappling with how moisture arrives this evening and overnightwith approaching low. Model profiles remain very dry throughmidnight in the mid levels, and think this keeps rain chanceslow. Initial onset may be low stratus or drizzle before showeryactivity moves in later.620am Update... Minor update to the near term portion of theforecast. Patchy fog continues across the region, mainly overthe inland valleys as reported by area observations as of 10Z.This fog will mix out over the next hour or two, allowing formostly sunny conditions, albeit hazy due to smoke crossing theregion from the northwestern United States and Canada.Temperatures will climb into the 80s this afternoon with coolingsea breezes along and near the coastline.Prev Disc...Fog will once again start out the day across portions of theforecast area this morning mainly over the interior valleys.This will lead to increasing sunshine and a light southerly flowarriving off the Gulf of Maine. It will be another warm daywith temperatures well into the 80s across the forecast areawith some 70s with onshore winds along the immediate beaches andshoreline.The latest HREF solution suggests some low cloudiness and patchyfog over the coastal waters may approach the coastline late inthe day. Some drizzle will remain off the coast.
-- End Changed Discussion --&&.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...Low cloudiness and fog will enter the coastline from the Gulf ofMaine tonight per latest model solutions. This will be ahead ofan easterly to northeasterly gradient ahead of low pressureretrograding towards the coastline north of Cape Cod. Scatteredshowers will enter southern areas in an increasing PWATatmosphere over two inches in spots. Operational models andensemble solutions continue to bring shower activity into theregion with overnight lows dropping into the 60s.Low pressure will reach southeastern portions of the forecastarea on Monday with more showers over the region, especiallyover far southern portions. Moderate to heavy rainfall ispossible, but it will likely be shunted to southern NewEngland.Patchy fog will continue especially along and near thecoastline. This will keep down high temperatures with lower 70salong the coastline with mid 70s across the interior. This islower than previous forecasts and with the low clouds and fog,may need to be lowered further.Expect to also see increasing waves and swell from this lowinto Monday. Criteria may satisfy 5 foot wave heights and 10sec periods for high surf, but need better confidence inobserved waves and location of the low. Either way, increasedrip current risk is expected along the coastline.&&.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...An upper low will linger over New England into Tuesday. Unsettledconditions will persist through the rest of the week asmultiple troughs approach from the west in a near zonal flowpattern across the northern CONUS. This pattern will bringchances for showers and thunderstorms most days while no one daylooks to be a wash out with likely some periods of sun and dryweather. The primary result of this stretch of unsettledconditions will be to temper the potential for hot conditionswith highs looking to top out in the mid to upper 80s. However,the humidity does increase during the week with dewpointsclimbing into the upper 60s to low 70s.The 12Z model suite is in good agreement that an upper low will bebacking into New England Monday morning with a weak surface low inthe Gulf of Maine. This system will wobble northward through Tuesdaybefore exiting into the Canadian Maritimes. Monday will berelatively cool along the coastal plain with ENE winds and mostlycloudy skies keeping highs in the 70s. The farther north and westone goes, there will be less clouds and warmer temperatures into thelow 80s. PoPs will increase through the day Monday into Mondaynight. Models do vary in the placement of highest PoPs so havegenerally kept them in the chance category through Tuesday. Beforethe upper low exits to the northeast Tuesday night a trough will bemoving in from the west. This trough will be advecting moistureinto the region with dewpoints climbing into the upper 60s tolow 70s by Tuesday afternoon. Highs on Tuesday will climb intothe mid to upper 80s.Additional shortwaves moving within near zonal flow will maintaintroughing over the Northeast as high pressure in the westernAtlantic hinders the eastward progression of these system. Thesewaves will maintain chances for showers and afternoon thunderstormsWednesday and Thursday. Dewpoints will remain elevated into the low70s while heat indices look to remain below Heat Advisory thresholdswith highs in the upper 80s. High pressure in the western Atlanticstarts to weaken late in the week. This will allow troughing to liftout of the region for a downward trend in PoPs Friday into theweekend.&&.AVIATION /13Z SUNDAY THROUGH THURSDAY/...Short Term...VFR conditions today. IFR and LIFR conditionspossible overnight tonight over southern areas with scatteredshowers and some drizzle possible. These conditions willcontinue to spread north on Monday.Long Term...Low pressure in the Gulf of Maine will bringlowering cigs and SHRA Monday night along the coastal plain.This will likely bring periods of MVFR for most TAF sites whileKLEB and KHIE have the best chance to stay VFR. There will bechances for showers and TSRA during the afternoons from Tuesdaythrough Thursday that will likely bring periods of restrictionswith night time fog also bringing the threat of restrictions.Otherwise, VFR will likely prevail during the day.&&.MARINE...Short Term...Below SCA today. SCAs have been issued for Mondayinto Monday night as low pressure turns towards the New Englandcoast. Waves and swell may quickly increase late to 5+ ftaround 9 sec. Fog may also develop over the waters today throughMonday as moisture increases.Long Term...Low pressure moving northwestward through the Gulfof Maine will bring building seas to 5-7 feet into Tuesday.Winds and seas stay below SCA thresholds late Tuesday throughThursday.&&.GYX WATCHES/WARNINGS/ADVISORIES...ME...None.NH...None.MARINE...Small Craft Advisory from 6 AM Monday to 6 AM EDT Tuesday for ANZ150-152-154.&&$$NEAR TERM...Cannon/CornwellSHORT TERM...CannonLONG TERM...Schroeter