Area Forecast Discussion
Issued by NWS Portland, ME

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401 FXUS61 KGYX 211329 AFDGYX Area Forecast Discussion National Weather Service Gray ME 929 AM EDT Thu Sep 21 2017 .SYNOPSIS... Jose will wobble around south of Cape Cod into the weekend, gradually weakening with time. It will produce some gusty winds at times along the coast into Friday and waves of high clouds. Otherwise high pressure will be the main feature and build south into the region as Jose weakens, making for fair weather and temperatures running well above normal Saturday through at least Tuesday. && .NEAR TERM /UNTIL 6 PM THIS EVENING/...
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930 am Update: Mostly sunny conditions expected the rest of the day except for some high cirrus at times due to Jose. Increased winds over much of the area allowing gusts to 25 mph at times, especially along the southern and coastal areas. Based on mesonet data, temps forecast looks good going forward. 615 am...Only minor changes to sky, to cover some patchy stratus early this morning, and T/Td. which were just tweaked based on current obs. Otherwise forecast unchanged. 10Z obs showing winds starting to gust up. Previously...Jose should stop its slow easterly movement this morning and then begin to shift very slowly back to the west. This had helped keep the winds generally fairly light across the CWA, but the shift back to the west should help tighten up the pressure gradient between the sfc high just to our north, so expecting to winds to pick up this afternoon, if not this morning, and it will become breezy, mainly along the coast with gust of 25-30 mph in the coastal zones and 20-25 mph in the next tier of zones just off the coast. For the most part should just see cirrus today, but it may come in thicker waves, so could see periods where it more cloudy, but overall partly sunny should cover it. Even though some cooler air aloft is moving in, it`s coolness is all relative and still above normal with 850 temps still around 12C, and with NNE winds should see some downsloping as well, especially in the CT valley, where highs could reach 80. The rest of the CWA should be in the low to mid 70s today.
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&& .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM FRIDAY/... Jose will become completely separated from any 500 mb flow by tonight, so it will remain nearly stationary, although with a bit of a westward drift through Friday. It will start to gradually weaken tonight as well, as it wobbles around near the nrn boundary of the gulf stream, so it may tap into some fuel in the warm waters on the nrn of the gulf stream, and will tend to hang on for a few days. Confidence is low in the little movements and their effect on our CWA, but should winds persist into tonight, although less gusty as mixing height lowers overnight. Those NNE winds will tap into some cooler sfc air to our N, so lows will drop into the mid to uppr 40s in the N, and in the low to mid 50s S. Models do suggest a surge of some clouds and maybe some light SHRA moving into the coastal zones late tonight into Fri morning, but with drier air working from the north, we may see it drying up before it gets here again, and forcing is not as strong as it was Tue into Wed, when we were lucky to squeeze out a tenth or two precip in some spots. Highs may end up a little cooler on Friday, especially in coastal areas, but should see most places reach 70 and generally will see highs 70-75. && .LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/... The models are now in decent agreement on the long wave pattern through much of next week. We begin the period with an upper ridge across northern New England and the remnants of Jose meandering well offshore to our south and east. The ridge will continue to strengthen as we head into the which time the remnants of Jose will finally be kicked well offshore. The eastern ridge and western trough will then hold across the CONUS through the start of the new work week with predominantly dry weather and abnormally warm temperatures to continue. By mid week...the ridge begins to weaken as the upper trough progresses eastward into the central CONUS. This opens the door for the tropical system to advance northward off the east coast...before being swept well offshore into the north Atlantic ahead of the advancing upper trough. The interaction of an approaching cold front and tropical moisture could produce some much needed rains late next week. && .AVIATION /14Z THURSDAY THROUGH MONDAY/... Short Term...Seeing mostly VFR this morning, although may see some patches of fog at KLEB, as we have seen already tonight, and also see some MVFR cigs at KRKD. Should see steadily VFR everywhere by around 12Z, which will hold into this evening. Coastal terminals could see some wind gusts to around 25 kt this afternoon. Long Term... Sat - Mon...Lcl IFR psb in valley fog btw 09-12Z each day. && .MARINE... Short Term...Jose will wobble around south of the Cape Cod today through Friday, and will see seas and winds surge up this afternoon into tonight, before they start to gradually diminish on Friday. Will probably see SCA conditions for part of Friday, at least outside the bays, especially for haz seas, but have held off for now, and see how things develop before extending. Long Term...SCA conditions are likely Friday through the weekend, mainly for seas, as Jose continues to meander south of Nantucket. && .TIDES/COASTAL FLOODING... Long period swells will continue through Thursday night. High tide at Portland is 10.3 ft around 1 AM, which is a little lower than previous nights, so some minor beach erosion remains possible. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...High Surf Advisory until 8 AM EDT Friday for MEZ023>028. NH...High Surf Advisory until 8 AM EDT Friday for NHZ014. MARINE...Small Craft Advisory until 8 AM EDT Friday for ANZ150>154. && $$ NEAR TERM...Marine SHORT TERM...Marine LONG TERM...Marine is the U.S. government's official web portal to all federal, state and local government web resources and services.