Area Forecast Discussion
Issued by NWS Portland, ME

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000 FXUS61 KGYX 231525 AFDGYX Area Forecast Discussion National Weather Service Gray ME 1125 AM EDT Sun Oct 23 2016 .SYNOPSIS... Low pressure in Quebec will gradually move further north today. In its wake rain and snow showers will continue in the mountains while elsewhere cloudy skies in the morning will give way to some sun in the afternoon. Windy conditions are expected today. Tonight clearing occurs across all areas as the dry west flow continues but diminishes. The cool cyclonic flow will continue through midweek. By the end of the week another upper trough will approach and move through the area with more unsettled weather. && .NEAR TERM /UNTIL 6 PM THIS EVENING/...
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Update... Have updated the grids based on current conditions and latest mesoscale model information. We continue to transition from a synoptically driven precip environment to purely an upslope flow event. Rain and snow showers will continue today, mainly across the west-northwest facing higher terrain. Current radar imagery continues to show a very good upslope signature, however some of these echoes are not reaching the ground downwind of the mountains. Made minor adjustments to temperature forecast and tweaks to the wind forecast. Winds continue to be very strong over the high terrain with over 100 mph winds on top of Mount Washington. Prev Disc... The center of low pressure is now located north of Maine along the St Lawrence river valley and moving north. In the systems wake a broad cyclonic flow will continue across the area today keeping rain and snow showers in the mountains and foothills. above 3000 feet a few inches of snow may accumulate. Over southern and downslope areas conditions will gradually dry out and the clouds will give way to some sun in the afternoon. With the strong westerly pressure gradient lined up vertically combined with cold advection aloft, mixing down of winds expected thus strong gusty winds today but should remain just below wind advisory criteria. Some exceptions will be over the higher terrain but will be localized. Temperatures will remain steady during the day or only rise a few degrees due to the strong cold air advection. Used a blend of models for max temps and for wind forecast relied on the WRFEMS which appeared better.
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&& .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/... The cool west flow continues tonight and Monday and all areas are expected to clear out except for some lingering clouds in the mountains due to orographics. Temperatures will be cool tonight through Monday. Winds will diminish some overnight but then increase and become gusty once again during Monday as a weak short wave exits to our south Monday. && .LONG TERM /MONDAY NIGHT THROUGH SATURDAY/... In the 500mb hemispheric pattern, any signs of of possible +PNA pattern break down toward the end of the week, although the ridging in the west and the troughing in east do set up a cool spell through Wed before large scale troughing over the ern CONUS breaks down and troughs become more mobile. This will allow for some warmer and cooler periods, but generally 850 temps stay with a few degrees C of normal late this week into next weekend. Mon night and Tue will see decent shot of energy swinging around base of the large scale trough, and deepening it while pulling even cooler air southward into New England. This will pull sfc and 850 mb low over the maritimes a little bit to the south and west and will keep decent gradient in the low to mid levels, so look for NW flow to persist with upslope showers continuing in the mountains. In fact, will likely see the upslope surge a little bit late Monday night into Tuesday as the wave moves through. Lows Mon night will be around 30 in the north to the mid 30s along the coast and In srn NH with highs on Tue ranging from the low 40s in the N to near 50 in the south. Tue night will see the NW flow slacken off a bit and with colder air place will see mins drop to the upper 20 N to the mid 30s S, but still too much flow to allow for any real rad cooling. Wed should be partly to mostly sunny with weakening NW flow as sfc high builds in, and max temps not all that different from Tue. Next system arrives late Thu into Friday, as sfc low tracks to our N and allows for some warning, buit also the threat for showers, mainly thu night into Friday. Sat remains uncertain with possible weak closed 500mb low in the vicinity, but it should cool down a bit for next weekend. && .AVIATION /16Z SUNDAY THROUGH THURSDAY/... Short Term...VFR conditions expected in all southern and downslope areas today while in the mountains mvfr conditions are expected in scattered rain and snow showers. Conditions will improve to VFR in the mountains tonight. All areas will be VFR on Monday. Long Term...Mainly VFR Mon night through Thu. KHIE could see some periods of flight restrictions in SHRASN Mon night into Tue. . && .MARINE... Short Term...A persistent West flow will keep Gales over the outer waters into tonight. Strong SCA conditions are expected in the bays through tonight. On Monday the west gradient winds will continue but will not be as strong. A SCA for the outer waters on Monday will likely be needed while in the bays, conditions should remain just below criteria. Long Term...SCA conds likely to persist through Tuesday and maybe into Tue night, but winds should subside for Wed and Thu. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...None. NH...None. MARINE...Small Craft Advisory until 11 PM EDT this evening for ANZ151- 153. Gale Warning until 11 PM EDT this evening for ANZ150-152-154. && $$ SYNOPSIS... SHORT TERM...Cannon LONG TERM...Schwibs is the U.S. government's official web portal to all federal, state and local government web resources and services.