Area Forecast Discussion
Issued by NWS Portland, ME

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000 FXUS61 KGYX 270216 AFDGYX Area Forecast Discussion National Weather Service Gray ME 1016 PM EDT Wed Apr 26 2017 .SYNOPSIS... Low pressure will slowly weaken and fall apart over Northern New England allowing for overcast skies and damp conditions to persist through Thursday night. A cold front will help to sweep out the cool and wet conditions Friday...with a trend towards warmer temperatures to start the weekend. That may be short lived however...as cooler air tries to slip back in from the north Sunday into Monday. && .NEAR TERM /UNTIL 6 AM THURSDAY MORNING/... 1010 pm...No forecast changes other than few tweaks to temps/wind based on current obs. Dense fog in some areas will continue to be the main issue through the morning. 755 pm...Stacked low south of Long Island this evening will continue to shift east and weaken tonight, and this should slowly move flow of showers off the Gulf of ME east as well, and generally reduce the coverage. Still, the lack of flow as col moves overhead, and any low level flow generally onshore will make for fog and drizzle persisting overnight into Thu morning. Some areas will see dense fog later this evening and overnight. Temps may drop off a few degrees overnight, but should bottom out in the upper 40s to low 50s. Low pressure off the coast of New Jersey will continue to slowly drift northwards and fill this evening. As it does rain will continue to rotate around the low bringing periods of showers through the evening. Between the rain showers low clouds and drizzle remain keeping everywhere damp. && .SHORT TERM /6 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/... Through the overnight hours the rain will come to an end but onshore easterly flow over the mid 40s ocean will continue. This moisture will allow for fog to develop. Dense Fog is possible along the coast with some sites to our south in Mass already reporting 1/4 mile visibility. High res ensemble also shows a significant chance of low visibilities and a Dense Fog Advisory may be needed overnight and into early morning. Have opted not to issue one at this time mainly due to the uncertainty in the geographical area. Some mountain sites have already seen dense fog as well as a few coastal locations. Expect fog to be widespread by some uncertainty still exists in the extent of the very low visibilities so have opted for areas and patchy dense fog for this forecast. As we move into the day on Thursday we`ll see a slight improvement in visibility through the morning but skies will remain overcast with periods of drizzle possible through the morning as the low continues to fall apart through the day. && .LONG TERM /FRIDAY THROUGH WEDNESDAY/... The extended forecast looks to feature generally Sly flow over the forecast area. L/wv trofing is forecast to set up to our W...allowing S to SW flow aloft and advection of warm fronts towards the area. Of course banking on warm fronts to push thru the forecast area is typically playing with fire...especially this time of year. The first comes following the passage of a s/wv trof Fri. After some early day showers...the question is how far N the warm front can make it into the area. If it can make steady progress thru the region it will be a mild day...but it may get hung up overhead and lead to a pretty large range in temps from N to S. Thru the rest of the weekend the front aloft looks to move into Quebec...but high pressure forecast to build N of the area will tend to lock the surface front in place. That would mostly likely lead to another round of rain/drizzle and low clouds until early next weekend when the cold front sweeps out the low levels. At this time no significant amounts of precip look likely...with either warm frontal forcing to our N or more progressive cold fronts moving thru the area. && .AVIATION /02Z THURSDAY THROUGH MONDAY/... Short Term... Widespread IFR conditions will deteriorate into LIFR overnight with 1/4SM fog at coastal sites. To the west in the CT River valley conditions will improve to MVFR for Thursday while across the coastal plain and mountains IFR with periods of drizzle will linger through Thursday. Long Term...A series of warm fronts will try and lift into Nrn New England thru the weekend. This will most likely lead to periods of widespread cloud cover. Significant periods of MVFR CIGs are likely...and areas of IFR could form in the overnights in onshore flow. Any IFR conditions would be most likely near the coast...with LEB and HIE being least likely to see significant impacts. && .MARINE... Short Term... Have dropped the Small Craft in favor of just the Hazardous Seas Headline. A few gusts to 25kts are possible this afternoon but winds will generally be diminishing. Seas will remain 4-6ft through Thursday as the low pushes easterly flow. Long Term...Persistent Sly flow across the waters will keep seas near 5 ft outside of the bays into the weekend. The warmer wind over cold water will likely keep wind gusts below thresholds...but a SCA may be needed for hazardous seas. && .FIRE WEATHER... Drizzle, low clouds and damp conditions will continue through the region today as low pressure east of New Jersey slowly fills through Thursday. && .HYDROLOGY... Other than drizzle and a few showers, rain has ended, and any rivers near or above action stage should crest well below flood stage overnight. && .TIDES/COASTAL FLOODING... A Coastal Flood Advisory is in effect for tonight. High tide at Portland is 11.5ft at 11:53pm. Storm surge is running above a half foot now, but should diminish closer to a half foot as we reach high tide. Some splash over and beach erosion will be possible through the early morning hours. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...Coastal Flood Advisory until 2 AM EDT Thursday for MEZ023-024. NH...Coastal Flood Advisory until 2 AM EDT Thursday for NHZ014. MARINE...Small Craft Advisory for hazardous seas until 8 PM EDT Friday for ANZ150-152-154. && $$ SYNOPSIS... NEAR TERM...Cempa/Curtis SHORT TERM...Curtis LONG TERM...Legro AVIATION...Curtis MARINE...Curtis/Legro FIRE WEATHER...Curtis HYDROLOGY... TIDES/COASTAL FLOODING...

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