textproduct: Caribou

WHAT HAS CHANGED

- Increased rain chances Thursday further north.

-Chance for another low pressure system and rain Sunday into Monday.

KEY MESSAGES

1) Fog likely tonight, especially Downeast. Fog could be dense enough to impact travel especially near the coast.

2) Periods of light rain late tonight, Thursday, and Thursday night, with higher totals Downeast.

3) Chance of rain and thunderstorms this weekend into early next week.

DISCUSSION

KEY MESSAGE 1...Fog likely tonight, especially Downeast. Fog could be dense enough to impact travel especially near the coast.

KEY MESSAGE 1 DESCRIPTION... Fog has mostly lifted this afternoon, with the notable exception of coastal Hancock County. The fog initially lifted this morning for coastal Hancock, but low clouds and fog have moved back in early this afternoon as onshore flow increases. Less fog right now for Washington County coast, but that should change this evening. Think that the Downeast coast could be in store for dense fog again tonight, with very moist low-level onshore flow persisting. Not quite confident enough yet to issue dense fog advisory for the coast, but it's definitely something to watch. Further inland tonight, while there will be some fog, think that the tendency will be for it to be mainly low clouds a couple hundred feet off the ground. Do have patchy fog in the forecast for all areas though.

Fog risk lessens some during the day Thursday and into Thursday night despite some light rain. This is because of the low-level flow becoming more easterly instead of southerly, which means a bit less low-level moisture coming off the Gulf of Maine. Still could be some coastal fog during the day Thursday and possibly anywhere Thursday night, but not anticipating anything too bad.

KEY MESSAGE 2...Periods of light rain late tonight, Thursday, and Thursday night, with higher totals Downeast.

KEY MESSAGE 2 DESCRIPTION... Low pressure passing south of the area will graze us with some light rain. This is not looking impactful in terms of flooding, and will be beneficial for many areas as it is getting fairly dry. In fact, there are some river and streams that are running close to record low levels for the date. The greatest rain totals from this system will very likely be Downeast. There is still a lot of uncertainty as to just how much rain makes it north of Bangor. Generally, models are trending a little wetter further north, and we are trending the forecast this direction. If rain does make it to far Northern Maine, most likely it would be during the day Thursday, ending Thursday evening. Downeast has a larger window of possible light rain from this evening through Thursday night, but it will be intermittent and not raining even close to the whole time. All together, we are looking at anywhere from a trace to quarter inch of rain for Northern Maine, a tenth to third of an inch central areas, and a quarter to three quarters of an inch Downeast. There could a couple embedded storms during the day Thursday Downeast and over the waters, but these will not be surface-based and not strong.

KEY MESSAGE 3...Chance of rain and thunderstorms this weekend into early next week.

KEY MESSAGE 3 DESCRIPTION... Some isolated showers with general thunder possible in the North Woods on Saturday. Low pressure system approaches from the west Sunday into Monday, bringing the next chance at steady rainfall. Low pressure swings into Maine as a high pressure system to the southwest pushes northeast into the Great Lakes region. Not anticipating heavy rain totals right now could see up to an inch in north, and up to of an inch Downeast. There could be some thunder moving along frontal boundary on Monday, with a few hundred J/kg of CAPE and 7-8C/km lapse rates. Too early to have confidence in any storm severity, however.

AVIATION /18Z WEDNESDAY THROUGH MONDAY/

Tonight...IFR/LIFR for BGR and becoming IFR by about 2z for BGR. For northern terminals, less confidence in low ceilings and IFR, but after about 7z, think there is about a 60 percent chance of IFR. Light and variable winds.

Thursday...IFR early, then generally MVFR by 16z, except possibly staying IFR all day at BHB. Intermittent light rain. Possibly a thunderstorm at BGR/BHB. E/NE winds 5-10 kts.

Thursday night...Lower confidence, with conditions ranging from IFR to VFR with some low clouds and fog, most likely BGR/BHB. N winds 5 to 10 kts.

Friday...MVFR/IFR early due to fog, then VFR/MVFR. Isolated rain showers in the afternoon. N winds at 5 to 10 kts.

Friday night...MVFR/IFR with any patchy fog late. Otherwise, VFR. Light and variable winds.

Saturday...MVFR/IFR in early morning fog. Otherwise, VFR. W winds 5 to 10 knots.

Saturday night...MVFR/IFR with any patchy fog late. Otherwise, VFR. Light S winds overnight.

Sunday...VFR/MVFR. A chance of showers. Slight chance of an afternoon thunderstorm. S winds 10 to 15 knots with gusts up to around 20 knots.

Sunday night - Monday...MVFR with rain showers, and afternoon thunderstorms. Light S winds Sunday night, becoming W/SW at 5-10 kts during the day Monday. Gusts to 20 kts possible.

MARINE

Tonight, seas less than 5 ft and winds 15 kts or less. Thursday and evening, seas other than the intracoastal waters could approach 5 ft, but not enough confidence yet to issue small craft advisory. Fog tonight over the waters, possibly lingering to Thursday night. A few thunderstorms possible over the waters during the day Thursday.

Outer waters could see 5ft waves into Friday evening. Afterwords, seas 2-4 ft rest of the weekend. NE winds Friday, shifting NW Saturday, and S by Sunday. Rain possible Friday, and again Sunday into Monday. Patchy fog Friday night.

CAR WATCHES/WARNINGS/ADVISORIES

ME...None. MARINE...None.