Area Forecast Discussion
Issued by NWS Portland, ME

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000 FXUS61 KGYX 211440 AFDGYX Area Forecast Discussion National Weather Service Gray ME 940 AM EST Tue Jan 21 2020 .SYNOPSIS... High pressure builds into the region today and crests over the region tomorrow with mainly clear skies. A warming trend develops for the second half of the week. A weak cold front will cross through Maine and New Hampshire Friday. Low pressure will cross just south of New England over the weekend. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 930 AM Update...Just a few minor adjustments to the going forecast this morning based on latest trends in observational data. Previously... 6am.. Have adjusted to current temperatures which as expected have quite a range. South of the mountains the valleys such as Fryeburg have continued to drop with mid teens below zero. Meanwhile the upslope clouds have come in and areas such as Whitefield have started to warm. prev disc... It`s a race to the bottom for temperatures this morning as clear cold high pressure along with fresh snow creates an excellent set up for radiational cooling. On nights like tonight just a few hundred feet of elevation or less can make a huge difference in temperature and that is reflected in the observations. So far -17 below at Lancaster, NH is the coldest but we still have a few more hours to go to hit 20 below. Have adjusted the temperatures down for this morning but it will be quite hit and miss as the valley bottoms drop like a rock. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/... For today look for high pressure to continue to dominate making for sunny skies. The sun and calm winds as the high crests overhead will make it feel warmer than the expected low 20s south to teens north. Tonight the clouds associated with a short wave currently north of lake Superior will move into the northern portion of the forecast area. While only a very slight chance for some flurries in the mountains the clouds should be enough to keep temperatures in that region considerably warmer than tonight. && .LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/... Very quiet conditions will continue for much of the work week. A warm trend will continue on Thursday as a large East Coast ridge remains over the region. H8 temperatures of around +2C will allow for daytime highs to reach the 30s in all areas. Clear skies and light winds will allow for radiational cooling Thursday night. Overnight mins will mostly be in the teens. On Friday, a cold front will slip through the region. It will be relatively unnoticed and moisture starved. Temperatures will fluctuate very little with the passage of this front. 00Z deterministic and ensemble guidance remains in relatively good agreement this morning from run to run. A slow moving, cutoff low pressure system will allow for intensification of a coastal system Saturday along the Mid Atlantic coastline. Models solutions continue to then diverge somewhat thereafter with the GFS and GEFS tracking the surface low the furthest north, across the southern tip of the Gulf of Maine on Sunday. The Canadian and Euro solutions remain further to the south which appear to be a reasonable solution. Will begin to highlight this system in our outlook and DSS products. With this type of track, much of the precipitation should be in the form of snow as drier air pours in from the lower levels out of the north. There still remains some uncertainty as to the speed of the system tracking underneath New England. && .AVIATION /15Z TUESDAY THROUGH SATURDAY/... Short Term...VFR conditions with SKC as high pressure slowly builds into the region. A few clouds may enter the northern zones by tonight but remain VFR. Long Term...Mainly VFR conditions through the work week. Conditions deteriorate this weekend as ceilings and visibilities may lower with precipitation entering the region this weekend. && .MARINE... Short Term...Calm winds and seas over the waters the next few days as high pressure crosses the region. Long Term...Winds and seas will remain below SCA thresholds as high pressure dominates the region. Gale force northeasterly winds are possible this weekend as low pressure tracks south of the region. && .HYDROLOGY... A number of ice jams are now in place on area rivers including the Kennebec between Augusta and Hallowell, Sugar river in Claremont NH and Swift River at Roxbury, ME. Currently no flooding impacts however ice jams can move at any point and interests near these rivers should pay close attention. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...None. NH...None. MARINE...None. && $$ is the U.S. government's official web portal to all federal, state and local government web resources and services.