textproduct: Caribou

WHAT HAS CHANGED

- 11PM Update: Added patchy fog in areas which received moderate rainfall this afternoon.

- 730 PM Update: prolonged isolated shower threat in Washington county this evening based on current radar trends and reduced precip coverage in the north based on the same. Updated Aviation section below with the 00z TAFs.

- Increased precip chances for Friday.

- Decreased winds over water through Friday night.

- Slowed down timing for onset of precipitation on Saturday.

KEY MESSAGES

1) Diurnally-driven afternoon convection today and Friday will bring measurable rainfall and an isolated tstm to portions of the area.

2) Unsettled weather pattern continues late Saturday through Tuesday, with an ongoing risk of rain across the region.

DISCUSSION

KEY MESSAGE 1... Diurnally-driven afternoon convection today and Friday will bring measurable rainfall and an isolated tstm to portions of the area.

KEY MESSAGE 1 DESCRIPTION... A shortwave passing through the area will take advantage of daytime heating to initiate pop up convection today for mainly northern areas. Showers are currently popping up across northern areas. Isolated lightning and graupel are possible in some of the stronger showers. Friday brings a similar set up with another shortwave and daytime heating to produce pop up showers for the whole area. Isolated lightning cannot be ruled out in some of the stronger showers.

KEY MESSAGE 2... Unsettled weather pattern continues late Saturday through Tuesday, with an ongoing risk of rain across the region.

KEY MESSAGE 2 DESCRIPTION... A mean trough remains over the eastern United States from Saturday through Tuesday. Shortwaves out ahead of this upper level trough will cause multiple periods of unsettled weather across the region during this time frame.

The first period will be from late Saturday afternoon into Sunday morning, when at the surface a weak low pressure system tracks from the eastern Great Lakes to New Brunswick during this time frame. Increasing low level warm advection will allow for rain to develop mainly across southern portions of the area Saturday afternoon/evening, then gradually push north into southeastern Aroostook late Saturday night, before tapering off from NW to SE Sunday morning. A few tenths of an inch of rainfall is expected with this system.

The next northern stream shortwave moving through on the front side of the mean trough will bring a wave of low pressure, moving along a slow moving frontal boundary that crosses Maine from NW to SE from Sunday into Sunday night. This will bring with it the threat of showers along and to the northwest of the front. The details of how the mid-upper level shortwaves track/interact or still being resolved, so the exact timing and location of rainfall with this system has a larger degree of uncertainty than is normal at this time range. There is the potential for a few tenths of an inch to upwards of 1 inch of rainfall with this system. For now, confidence in any thunder with this system is too low to reflect in the forecast.

Yet another low will ride along the front Monday and Monday night, but at this time, it looks to pass to the south of Maine and probably far enough south that mainly Downeast Maine will be impacted.

The main mid-upper level trough moves over Maine on Tuesday - bringing with it isolated to scattered convection. At this time, there is too much uncertainty to determine the strength of this convection and if there will be any thunder with this system.

Temperatures should generally be near normal this weekend, then below normal Monday and Tuesday.

AVIATION /02Z FRIDAY THROUGH TUESDAY/

Tonight: VFR southern terminals with generally VFR conditions at northern terminals, though SCT to BKN MVFR cigs are possible. NW winds 5 to 10 kts with some gusts 15 to 20 kts in showers will quickly taper off, becoming light and variable overnight at all terminals.

Friday: Mainly VFR conditions across all terminals. Rain showers possible in the afternoon, with showers most likely at KHUL but could impact KCAR/KPQI up through KFVE at times. NW winds 5 to 10kts with gusts 15 to 20 kts in the afternoon.

Friday night: VFR with light SW wind.

Saturday: VFR in the morning. VFR at northern terminals with a chance of MVFR or IFR at southern terminals Saturday afternoon. SW-S winds G15-20KT possible.

Saturday Night...MVFR or lower likely at KBGR/KBHB and possible at KHUL, with VFR elsewhere. SW winds G15-20KT possible at northern terminals. LLWS possible at southern terminals.

Sunday-Sunday night: MVFR or lower possible. SW-W winds G15-20KT possible Sunday.

Monday-Monday night: VFR northern terminals, with MVFR or lower possible at southern terminals.

Tuesday: Low chance of MVFR in any convection, otherwise VFR.

MARINE

Below SCA conditions expected through Friday night.

Sub-SCA conditions on the intra-coastal and coastal waters Saturday, followed by gusts there of 25-30KT Saturday night and Sunday. SCA conditions could linger into Sunday on the coastal ocean waters Sunday night, then sub-SCA conditions on the intra-coastal waters Monday-Tuesday.

For the outer waters: Wind gusts of 25-30KT are likely Saturday- Sunday night, with seas greater than 5 ft. Seas greater than 5ft are also possible Monday night and Tuesday. Winds/wind gusts should be 20 kt or less and seas 5 ft or less on Monday.

CAR WATCHES/WARNINGS/ADVISORIES

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