Area Forecast Discussion
Issued by NWS Portland, ME
Issued by NWS Portland, ME
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278 FXUS61 KGYX 050402 AFDGYX Area Forecast Discussion National Weather Service Gray ME 1202 AM EDT Fri Jul 5 2024 .SYNOPSIS... Mostly cloudy skies are expected through the end of the day Friday. Mostly dry conditions are expected this evening, then scattered thunderstorms are possible tomorrow afternoon. Friday night, a low pressure system moves into the region bringing widespread showers and thunderstorms Saturday. Skies clear out on Sunday, with a tranquil Monday expected before unsettled weather returns to the forecast for Tuesday. && .NEAR TERM /UNTIL 6 AM FRIDAY MORNING/... 1140pm Update...Showers have indeed held off thus far. There is some reflectivity moving across NY and into VT, but MRMS puts many of this as high level and likely above a stout dry layer. Thus I wasn`t in a rush to add back PoPs for the overnight period. There does appear to be some speed convergence and elevated instability that could result in a built up shower eventually overnight, but this may be towards the morning when conditions are more favorable anyway. A few signs of fog or low stratus developing towards Penobscot Bay where temps have cooled off well amid light onshore flow since this evening. 715pm Update...Quick update here with few changes. Did reduce shower coverage for the evening hours. Have observed a number of cu get started amid favorable low level lapse rates, but quickly dissipate due to much weaker mid level LRs as well as a broad layer of dry air. Can`t rule out a very isolated sprinkle early on, but think these would be short lived. Otherwise, surface inversion sets up this evening with light onshore flow becoming more variable overnight. Previous Discussion... A cold front continues to dissipate across the area this afternoon, bringing scattered clouds and an isolated shower into the evening hours. Moisture continues to stream northward into the area overnight, bringing higher dew points and overnight low temps in the mid 60s to low 70s. With this moisture, patchy marine fog is likely to develop along the coastline tonight, and possibly extend into parts of central Maine as well. && .SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY/... What`s left of the original cold front slowly lifts back northward through the area tomorrow, bringing a few more showers and an isolated thunderstorm throughout the day. Dew points will be quite high tomorrow, with most areas seeing afternoon readings in the low to mid 70s. With this moist airmass, fog looks likely to hang on along the immediate coastline and into the MidCoast through at least midday tomorrow. Elsewhere, temps warm into the low to mid 80s with a mix of sun and clouds, outside of the scattered showers. Instability increases through the daytime, with chances for showers and thunderstorms increasing during the afternoon hours. The best chances look to be across southern New Hampshire by the mid afternoon, with these then drifting into coastal areas by the late afternoon. We catch a break in the action through the late evening and into the overnight hours tomorrow night, but then a more widespread area of showers and storms looks likely to develop later tomorrow night. This is in association with an upper level low rotating through the Great Lakes tomorrow through Saturday. The best chance of rain tomorrow night looks to be across northern and western areas, but most of the area could get in on the rainfall by daybreak Saturday. There`s still some uncertainty with this feature, as it`s not very often we see convection developing and increasing through the overnight hours. I held off on going all in with POPs tomorrow night, with most areas maxing out at low likelies, allowing for a little more time to get a better handle on the expected evolution of the convection developing. There is still a chance more of it could swing west of the area, or that the areal coverage isn`t all that impressive, similar to what the 3km NAM is suggesting. && .LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/... ----------------------------------------------------------------- Summary: *Stormy Saturday ahead. *Temperatures expected to run above average through early next week. *Pleasant weather likely on Monday, through scattered storms return on Tuesday. ----------------------------------------------------------------- Discussion: A low arrives on Saturday, bringing scattered showers and storms early in the morning. This round of showers are anticipated to dissipate during the late morning hours. Afterwards, the environment looks to destabilize as clouds clear out at daybreak. Storms could generate all over the northeast Saturday afternoon and quickly move into New Hampshire and Maine by the evening hours. Hi-res forecast soundings indicate that a few storms that move across northern New England Saturday evening could become severe. Most of the inclement weather exits the region by Sunday morning, through a few showers might linger around up along the Canadian border. Otherwise, Sunday and Monday are forecasted to look and feel pleasant, with weak ridging nudging temperatures a little above average and much drier air in place as well. Unsettled weather returns to the forecast Tuesday and may continue through the rest of the week. && .AVIATION /04Z FRIDAY THROUGH TUESDAY/... Short Term...Marine fog and stratus likely arrive along the coastal terminals and AUG tonight with IFR conditions, lingering into the mid morning hours. RKD likely holds onto the marine fog through midday tomorrow, before a break. Interior areas may see brief restrictions late tonight, but looks less likely. VFR prevails away from the coast tomorrow, then most areas lower to IFR with marine fog and showers later tomorrow night. Long Term... IFR possible Saturday morning with low visibility as showers and thunderstorms move through the region. Visibility improves by the end of the day with thunderstorms possible. The storms exit the region by Sunday morning with VFR likely. Pleasant weather continues on Monday as well, but some fog is possible along the CT River Valley and the Midcoast. && .MARINE... Short Term...A front dissipates near the waters tonight, and then lifts northward as a warm front tomorrow. Increasing moisture leads to patchy dense fog developing tonight, and likely lingering through at least tomorrow night. Conditions remains below SCA through tomorrow night. Long Term... Southerly winds at 15-20kts are expected Saturday morning with the onset of a low pressure system. Seas are expected to gradually increase on Saturday with up to 3 foot seas to start the day and up to 5-6 foot seas by Saturday night. SCA Issuance is likely on Saturday. By Sunday morning, the low exits the region, shifting and simmering winds down to 7-12kts from the southwest. Seas decrease through the day Sunday too, with 2-4 foot seas by the end of the day. Seas and wind remain low on Monday. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...None. NH...None. MARINE...None. && $$ SYNOPSIS...Palmer NEAR TERM...Clair/Cornwell SHORT TERM...Clair LONG TERM...Palmer AVIATION...Clair/Palmer MARINE...Clair/Palmer