


Area Forecast Discussion
Issued by NWS Portland, ME
Issued by NWS Portland, ME
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479 FXUS61 KGYX 070134 AFDGYX Area Forecast Discussion National Weather Service Gray ME 934 PM EDT Fri Jun 6 2025 .SYNOPSIS... Showers and thunderstorms will be prevalent tonight as a stationary front stalls over the area. This feature will linger into Saturday, once again focusing shower development. Strong to severe storms with localized flash flooding will be possible through this evening. The next round of rain could pose additional flood concerns for Saturday. A break arrives Sunday as high pressure briefly builds. Conditions become unsettled with the next week with widespread showers Tuesday into Wednesday. Improving conditions expected for the second half of the week. && .NEAR TERM /THROUGH SATURDAY/... 930 PM Update... Cancelled the flood watch in NH as the vast majority of the rain is now over ME and the threat for additional flooding is low for the overnight hours. Otherwise, just loaded in the latest surface observations at this time. Previously... 700 PM Update... Convective rain continues to spread east over the area at this hour with the back edge of the heaviest rainfall now approaching the CT River Valley of NH. Rainfall rates between 1.5-2.5"/hr are being observed in some locations, which has been enough to cause some minor flash flooding and poor drainage flooding. Heavy rainfall and embedded thunder will continue to slide east through the remainder of the evening before becoming more scattered in nature overnight. Previously... Large scale ascent is just now arriving over the forecast area and as a result convection is beginning to pop over parts of NH. Coverage of showers and storms will continue to expand north and east from this point. Especially over the southern half of NH and adjacent southwestern ME there is enough instability for stronger storms. However we are lacking in shear...so organization is going to be tough to come by this afternoon and evening. This should lend itself towards pulse-type convection and/or merging cold pools as storms cluster together later. There may initially be some hail...but as time goes on wind will become the more dominant hazard. Once we lose daytime heating the storms will also lose their punch and start to scatter out. There is more in the hydrology section below...but we also look on track for heavy rainfall from any convection. HREF guidance continues to show max QPF in the 3 to 4 inch range over 6 hours this evening. This may also occur over a couple of rounds...allowing the soil to saturate before the next round arrives. After the storm complex dissipates it will remain pretty moist over the forecast area and fog may develop after midnight. It will be highly dependent on how convection evolves over the next few hours...so I have just patchy fog mention for now. && .SHORT TERM /SATURDAY NIGHT THROUGH 6 PM SATURDAY/... The frontal boundary will linger into Saturday, with a wave of low pressure riding along it. This will renew widespread showers with some scattered convection. The environment will not be supportive of severe storms due to limited shear and cape, but there will be enough energy for periods of heavy rainfall. This rain falling on already saturated grounds from Friday could be sufficient to renew very localized flash flood concerns, and potential for another flood watch. This will be dependent on how this evening plays out and where the axis of heaviest rain falls, before focusing on an area of flood risk tomorrow. Expansive cloud cover and showers will keep temperatures capped around 70. Some peaks of sunshine are possible in western counties towards the end of the day as the front pushes east, but most are the area will remain gloomy. && .LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/... Ridging builds in Sunday providing a break in the weather with sunny conditions and lower humidity. A negatively-tilted wave swinging by Monday, increasing clouds and scattered showers with cooler temperatures in the 60s. Conditions briefly dry out Monday Night before a more amplified and organized upper trough moves over the Great Lakes Tuesday. Increasing rain chances with isolated thunder will develop as the system approaches, with the cold front passing Tuesday night into Wednesday morning. Looking at likely pops, and WPC Day 5 marginal ERO risk already clips the Connecticut Valley. Afterwards high pressure build in from the west and conditions dry out with seasonable temperatures through the end of the week. At the time of this issuance next Saturday`s forecast looks favorable with a low probability for rain. Could it end the 12-13 straight rainy Saturday run? Time will tell. && .AVIATION /02Z SATURDAY THROUGH WEDNESDAY/... Short Term...Scattered showers and thunderstorms will track across southern NH into southern Maine through this morning that will bring brief restrictions if the encounter any TAF site. MOre widespread thunderstorms are likely this afternoon into the evening with mainly VFR prevailing outside of any shower or storm. Low cigs and fog will likely bring IFR/LIFR across much of the area tonight. Some improvement is possible Saturday morning while another round of showers and storms is likely late Saturday morning into the evening. Long Term...Conditions will gradually improve Saturday night with VFR likely Sunday. Chances for showers increase Monday into Tuesday that could bring periods of restrictions. && .MARINE... Short Term...VSBY restrictions possible in showers/thunderstorms and even some fog over the waters through Saturday. Long Term...Sub-SCA conditions. VSBY restrictions in showers Tuesday/Wednesday. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...None. NH...None. MARINE...None. && $$ NEAR TERM...Tubbs SHORT TERM...Legro LONG TERM...Jamison