![National Oceanic and Atmospheric Administration](/build/images/header/noaa.d87e0251.png)
![National Weather Service](/build/images/header/nws.4e6585d8.png)
![United States Department of Commerce](/build/images/header/doc.b38ba91a.png)
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
44
45
46
47
48
49
518 FXUS61 KGYX 131020 AFDGYX Area Forecast Discussion National Weather Service Gray ME 620 AM EDT Sat Jul 13 2024 .SYNOPSIS... Showers and a few thunderstorms move through this morning, then some scattered storms are possible this afternoon as a cold front pushes through New England. Drier air works into the region tonight and Sunday, though temperatures will climb. Humidity will increase on Monday and Tuesday before a stronger cold front arrives Wednesday with the potential for some showers and thunderstorms. Cooler and drier conditions arrive behind the front for the end of next week. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... 6:20am Update... Adjusted POPs based on radar trends so far this morning as the first batch of showers move through. Another area of showers is moving northeastward from Mass, and likely clips mainly southeast NH and York County over the next few hours. Isolated showers then linger with increasing sunshine early this afternoon before a broken line of showers and storms moves through with the cold front mid to late afternoon. Previous... Showers and storms move through the area early this morning as moisture rides northward from a disorganized system across the Mid Atlantic and interacts with the stalled frontal boundary across Maine and New Hampshire. Some heavier downpours have been observed with storms so far, but overall these look to be weakening as they continue to move eastward. The first round early this morning looks to be the most well defined, and then some scattered shower activity continues through the morning. A break in the showers is expected through the early afternoon, with a mix of sun and clouds and temps warming into the mid to upper 80s in most spots. Some scattered showers and storms are then likely to accompany a cold front moving through during the mid to late afternoon hours. These storms likely reach the coastline toward sunset, with most of the activity coming to an end shortly after dark. && .SHORT TERM /6 PM THIS EVENING THROUGH 6 PM SUNDAY/... Somewhat drier air works its way into the area overnight tonight, allowing lows to dip into the 60s across most of the area, with low 60s across northern areas. While still above normal, they will be some of the cooler readings we`ve since in the last few nights. After showers and storms move offshore during the evening, the rest of the overnight looks dry and quiet. Patchy fog is likely to develop, particularly through the river valleys, and in areas that see the afternoon showers and storms. While the humidity will be a bit lower tomorrow, temperatures will be on the rise as a southwesterly flow pushes temps into the low to mid 90s across most spots outside of the higher terrain. The immediate coastline is likely to see some relief in the afternoon with a seabreeze developing as the high pressure center moves offshore, but likely not before reaching near 90 degrees. An isolated shower can`t be ruled out across the higher terrain, but otherwise a mainly dry and sunny day is expected. && .LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/... A persistent period of hot, hazy and humid weather will continue until a potentially significant change in the weather pattern arrives late next week... We begin the long range portion of the forecast on Sunday with operational models and ensemble solutions suggesting a large and significant upper level ridge remaining off the seaboard. This will leave the region with hazy, hot and humid conditions over the region. Temperatures will likely reach 90 degrees across the interior and along the coast from approximately Portland and points south along the shoreline. This may be the start of the first heat wave for portions of the coast, and a continuation of persistent heat waves across the interior. This will also be the first day of the return of hot conditions after one day of clouds and slightly less warm conditions from the start of the weekend. Hot temperatures return to the interior once again on Sunday, in areas where heat indices have been skyrocketing over the last couple weeks. After the short reprieve, this will be a renewed period of heat wave conditions for much of the region. While seabreezes will likely cool off the shoreline slightly during the afternoon, this warm spell will be noted by more of a westerly flow aloft, potentially allowing temperatures to reach 90 degrees in the Forest City as well as much of the southwest coast of Maine and Seacoast of New Hampshire before any onshore winds develop. Surface dew points will be slightly lower than this past week, but nevertheless, hot and humid conditions will lead to a prolonged period of stressful conditions for outdoor activities and areas without proper air conditioning. By Monday, heights aloft will gradually be lowering without any defined short wave in place. This will allow for a primarily afternoon, diurnally driven scattered shower and with sufficient instability, perhaps a thunderstorm or two. Temperatures will be outright hot with lower to mid 90s expected in all portions of the forecast area. The only exceptions will be the higher terrain in the mountains and the Midcoast area of Maine where onshore winds will allow readings to remain in the 80s. It will be humid with dew points continuing in the upper 60s, which is actually a very mild improvement from the lower to mid 70s dew points recorded much of this week. Tuesday will be similar to Monday in terms of the chances for precipitation and hot and humid temperatures across the region. Tuesday may be day 3 of 90 degrees or higher in a row in Portland which would be potentially its first heat wave of the summer, while the interior continues its heat. This all comes with sunshine, good mixing and H8 temperatures near +18C. During the muggy period, expect periods of patchy fog. This will be most likely during the overnight periods along the interior valleys and also potentially near the coastline. More heat on Wednesday with perhaps more scattered showers and storms. Temperatures have the potential to hit 90 or above many areas. However, model ensembles suggest a significant pattern change at this juncture as an upper level trough builds towards the region. Canadian high pressure may build into the region for the later portion of the weak, bringing cooler and much drier air to the forecast area. && .AVIATION /10Z SATURDAY THROUGH WEDNESDAY/... Short Term...Showers bring brief restrictions this morning, then VFR prevails for most of the day at most terminals. RKD is likely to see marine fog develop and linger through the morning, bringing IFR conditions for a few hours. An isolated shower or storm is possible this afternoon, but PROBs remain low. Valley fog is likely tonight, especially at LEB and HIE. VFR prevails elsewhere through tomorrow, with VFR returning to all terminals tomorrow morning. Long Term...Mainly VFR conditions through much of the period. There will be a chance for IFR conditions in any scattered showers or thunderstorms mainly during the afternoon periods. The exception will be Sunday when conditions will be dry all areas. Patchy fog will continue, mainly at night and mainly over the interior valleys and perhaps the coastline. && .MARINE... Short Term...Seas continue to ease as a stalled front lingers west of the waters. The front crosses the waters tonight, with high pressure then building in behind the front tomorrow. Long Term...South to southwest winds will continue through the weekend and into much of next week. Winds and seas should remain just below SCA thresholds each day with sea breeze circulations increasing the gradient and resultant wind fields during the afternoon periods. Patchy fog expected mainly during the nighttime and overnight periods && .GYX WATCHES/WARNINGS/ADVISORIES... ME...None. NH...None. MARINE...None. && $$ NEAR TERM...Clair SHORT TERM...Clair LONG TERM...Cannon