Area Forecast Discussion
Issued by NWS Portland, ME

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000 FXUS61 KGYX 281538 AFDGYX Area Forecast Discussion National Weather Service Gray ME 1138 AM EDT Tue Mar 28 2017 .SYNOPSIS... Low pressure will pass to our south later today and tonight. A cold front will cross the area of Wednesday. Northwesterly flow will continue on Thursday behind the front with a few showers possible in the northern mountains. High pressure will build into the region through Friday. Low pressure will approach the region Friday night into Saturday with snow and rain possible in the south. && .NEAR TERM /UNTIL 7 PM THIS EVENING/... 1138 AM...For this ESTF update I ingested the current mesonet into near term grids. Seas continue to drop off and the small craft for seas has been dropped with this update. Prev Disc... 845 AM...Minor ESTF update to reflect current radar and observational trends in near term grids. Prev disc ... 635 AM...MAde some tweaks to temps and pops based on current obs, but overall forecast is unchanged. A few radar echoes moving across mid-coast, but no ground truth to go along with them, although should be moving over KRKD shortly. Other than that should be mostly dry through mid-morning with just some spotty DZ/FZDZ in the mtns, but this too looks limited. Previously...Stagnant flow is the main feature for today as weak mid lvl ridging between twos systems combines with weak sfc cold air damming to allow for clouds and fog to persist thru today. As weak low pressure passes to our south and north could see a few shra pop up this afternoon, although the best chc for any precip will be this evening. Highs will range from the upper 30s in the north to 40 along the coast, and into the mid to upper 40s in srn NH and the CT vly, where some southerly flow will warm things up a bit ahead of the cold front. && .SHORT TERM /7 PM THIS EVENING THROUGH 6 PM WEDNESDAY/... Models are coming into a little better agreement that precip from the sf low passing to ours south should bring at least some showers into southern parts of the region a few hours either side of 00Z. Also cold front should produce some showers in the mtns this evening as well. The lowest chance for any precip is in the central zones, but still cannot rule out a few showers here either. Upslope showers in the mountains should transition to snow showers late this evening and overnight. Lows will range from around 30 in the north, to the mid 30s in the south. The cold front will cross the region by Wed morning and winds will shift to NW and pick up. This should allow for some clearing on the coastal due to downslope, and, also allow for highs to rise well into the 40s to around 50 in the warm spots in the south. The mountains will remain mainly cloudy with sct snow or rain showers. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... The relatively fast moving zonal flow continues through the extended period with a series of disturbances affecting our region. This fast moving flow with lots of waves leads to a relatively low predictability and low confidence forecast through the extended. Northwesterly flow continues on Thursday as the upper low departs to our east. With drying conditions just a few showers along the international border are expected. High pressure again builds into the region on Thursday night and into Friday. Clouds will again be on the increase Friday night ahead of the next developing low. A low will develop in the midwest late thursday into Friday and move northeastwards to impact our area late Friday night into Saturday. There is still a lot of uncertainty with this system as the fast paced zonal flow makes for small differences in timing and strength of the waves being reflected in larger changes in the forecast track of the low. Overall the trend is south and out-to-sea as compared to yesterday however this would still leave the southern portion of the forecast area in the precipitation shield for Saturday with some showers extending across the entire CWA. Still not confident in this track and think we will need to actually see the low reforming out of the rockies before any of the models can get a grip on it. Have trending south with the mean for this update. As far as ptype goes, it is late in the season to see any good damming so expect a straight rain/snow mix. && .AVIATION /15Z TUESDAY THROUGH SATURDAY/... Short Term...IFR to LIFR conds persist through today and into tonight. Look for improvement to VFR during Wed morning, with NW winds gusting to 20-25 kt in the afternoon. Long Term... Thursday will see just a chance for MVFR showers remaining in the far north CWA. High pressure will move in resulting in VFR through Friday morning. Friday evening southern NH will see a decrease to MVFR in showers with IFR possible from PSM to CON and along the extreme southern Maine coast. && .MARINE... Short Term...Winds continue diminish this morning and remain light into tonight. Seas will continue to slowly subside, but will still sea 506 ft thru this morning outside the bays so have extended SCA thru noon. Cold front move thru late tonight, and will likely need SCA again by Wed afternoon. Long Term... Northwesterly flow will continue on Thursday with small craft conditions expected to persist through mid day. Another low may move through the southern portion of the waters on Friday night. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...None. NH...None. MARINE...None. && $$ ES is the U.S. government's official web portal to all federal, state and local government web resources and services.