Area Forecast Discussion
Issued by NWS Portland, ME
Issued by NWS Portland, ME
Versions:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
191 FXUS61 KGYX 172314 AFDGYX Area Forecast Discussion National Weather Service Gray ME 714 PM EDT Tue Sep 17 2024 .SYNOPSIS... High pressure will remain entrenched east of the region through midweek before some moisture over the southeastern states builds north increasing the chance for showers south of the mountains Wednesday night and Thursday with cooler temperatures. Canadian high pressure builds in from the north to end the week and through the weekend with seasonable temperatures and dry weather expected. && .NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/... 710 PM Update...Very little change to the going forecast. Light winds, radiating temperatures, and thin strands of cirrus floating overhead will be the story this evening. Previously... High pressure over the western Atlantic remains in control tonight while high clouds from a system over the Mid Atlantic continue to stream overhead. Lows tonight will drop into the 50s with favorable radiational cooling spots dropping into the 40s. Fog will likely develop along the CT Valley with the 12Z HREF suggesting some marine stratus and fog will push into the immediate coast. && .SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/... Ridging aloft starts to break down Wednesday while high pressure over the western Atlantic continues to keep the area dry. Moisture from the system over the Mid Atlantic makes subtle progress northward resulting in skies trending partly to mostly cloudy across the far south while northern areas likely see more sun than clouds. It will again be warm with highs into the 80s while stronger onshore flow will keep coastal areas in the 70s. High pressure shifts east into the Atlantic Wednesday night while an area of low pressure attempts to get organized south of Long Island, NY. This system will bring more in the way of clouds to the region with skies becoming mostly cloudy south of the mountains. There also looks to be better inland penetration of marine fog Wednesday night. Lows will generally be in the 50s. && .LONG TERM /THURSDAY THROUGH TUESDAY/... 12Z operational models and ensemble solutions continue to indicate a disorganized area of low pressure will be centered off the Northeast coast at the beginning of the extended period. Moisture attempts to advect towards the Maine and New Hampshire coastline with the best chances for precipitation Thursday into Thursday night. Whether or not these showers will reach southern portions of the forecast area will be highly dependent on the amount of dry air in place over northern New England in which the system would need to displace. For the time being, will only have low probabilities for precipitation as our very dry period continues across the region. An upper level trough may bring a sprinkle or an isolated shower to the interior of Friday. However, yet again any precipitation would be very light. Otherwise, high pressure over eastern Canada will keep us dry over the weekend and into early next week. Above normal temperatures on Thursday will be replaced by seasonable readings for the remainder of the extended forecast. Coastal Flooding...The onshore winds forecast for the coast late in the week will coincide with very high astronomical tides. This may lead to minor coastal flooding near the times of high tide. && .AVIATION /23Z TUESDAY THROUGH SUNDAY/... Short Term...Mainly VFR through the first part of tonight. Some marine fog/stratus may impact KRKD, KAUG, and KPWM later tonight into day break with valley fog likely bringing LIFR to KLEB and KHIE. Conditions improve to VFR for all TAF sites Wednesday. Marine fog/stratus will again have the potential to impact KRKD, KAUG, and KPWM Wednesday night with patchy fog possible at KHIE and KLEB. Long Term...VFR likely prevails during the day time Thursday through Sunday. Night time valley fog will bring the potential for IFR/LIFR most nights at KLEB and KHIE. Onshore flow and increasing clouds from a system passing south of New England will also bring the potential for cigs around MVFR thresholds Thursday and Thursday night and possibly into Friday. && .MARINE... Short Term...Winds and seas remain below SCA thresholds tonight through Wednesday night as high pressure over the western Atlantic extends into the Gulf of Maine. Marine fog has the potential to develop over the Gulf of Maine tonight and persist Wednesday into Wednesday night. Long Term...Winds and seas remain below SCA thresholds Thursday. a northeast flow will develop Thursday as low pressure approaches and stays south of New England. Low pressure passing south of the Gulf of Maine will bring seas building to 5 ft by Friday with continued NE flow with gusts around 25 kts. Seas remain elevated around 5 feet into the weekend with NE winds subsiding from their peak on Friday. && .GYX WATCHES/WARNINGS/ADVISORIES... ME...None. NH...None. MARINE...None. && $$ NEAR TERM...Ekster/Schroeter SHORT TERM...Schroeter LONG TERM...Cannon