textproduct: Caribou

WHAT HAS CHANGED

- Added small hail to the forecast for central portions of the area Wednesday afternoon.

KEY MESSAGES

1) Less rain late this afternoon into tonight, but areas of fog could impact travel areawide.

2) Numerous showers and scattered storms Wednesday afternoon, with the best chance over central portions of the area for places like Greenville, Houlton, and Millinocket. A few storms could produce small, non-severe hail.

3) Unsettled weather continues into the weekend.

DISCUSSION

KEY MESSAGE 1...Less rain late this afternoon into tonight, but areas of fog could impact travel areawide.

KEY MESSAGE 1 DESCRIPTION... The present weather system is exiting, with just some drizzle or very light rain persisting mid-late this afternoon. Clouds are rather stubborn to leave though. Even though we could see a bit of clearing this evening, think that with light winds and abundant low-level moisture, fog will quickly fill any areas that do clear out. Have areas of fog in the forecast tonight. Can't rule out some denser fog, but just don't have the confidence to put this into the forecast. Regardless, if traveling tonight, leave extra time and be prepared for low visibilities.

KEY MESSAGE 2...Numerous showers and scattered storms Wednesday afternoon, with the best chance over central portions of the area for places like Greenville, Houlton, and Millinocket. A few storms could produce small, non-severe hail.

KEY MESSAGE 2 DESCRIPTION... An approaching upper trough from the northwest will help ignite quite a few showers and storms Wednesday, with coverage being numerous from midday into the afternoon. Not an all-afternoon rain, but a decent chance for areas north of Bangor you'll get a shower or storm at some point. Surface-based CAPEs will be up to as high as 1000 J/kg, which is decent but not great. Not much wind shear directionally or speed-wise. With fairly cool air aloft, though, could be some small hail with the best chance over central portions of the area, and added some small hail in for places like Greenville, Millinocket, and Houlton. Though we can't rule out an isolated storm reaching severe criteria (1 inch diameter hail), think the vast majority of storms will just have pea-sized hail at best. Think that storm motion will be sufficient to limit flash flooding threat. Coverage of showers/storms will be less from Bangor south to the coast. Shower/storm activity dies off around sunset Wednesday.

KEY MESSAGE 3...Unsettled weather continues into the weekend.

KEY MESSAGE 3 DESCRIPTION... The large vertically stack low pressure system will progress from the Great Lakes towards the region Thursday night and Friday. The concern for Friday will be the intensification of the low pressure system, thus stronger instability with the cold front. Newer extended model runs show the majority of the instability in the south, however, mid term models show less instability. This uncertainty will require newer updates to pin down location and timing.

AVIATION /18Z TUESDAY THROUGH SUNDAY/

Rest of Today and Tonight... Generally MVFR/IFR this afternoon. Some spots could briefly get VFR late this afternoon or early this evening, but anticipate any clearing will be short-lived as low clouds and generally IFR or lower take over later tonight. Still a fair amount of uncertainty is just how low conditions go tonight, but can't rule out dense fog at any TAF site esp after 4z...just don't have the confidence to put into TAFs. Light winds.

Wednesday... IFR/MVFR should improve mostly to VFR by about 16z, but then showers/storms develop esp N of BGR, with any showers/storms briefly bringing conditions back side to MVFR/IFR. NW wind 10 kts.

Wednesday Night... Generally VFR, though chance of MVFR/IFR in fog mainly at Aroostook terminals. Light winds.

Thursday-Saturday: VFR, except for MVFR or lower possible in any showers and possible thunderstorms, mainly at northern terminals and mostly in the afternoon. Winds generally 5 to 10 kts out of the S Thursday-Friday, returning to NW Saturday. Light and variable winds each night.

Sunday: MVFR in rain showers. NNW winds 5-10 kts.

MARINE

Winds/seas diminishing late this afternoon/evening to less than 25 kts/5 feet and remaining at these levels into Wednesday night. Some fog on the waters later tonight and Wed morning.

Winds and seas remain below SCA levels Thu-Sunday.

CAR WATCHES/WARNINGS/ADVISORIES

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