textproduct: Caribou

WHAT HAS CHANGED

- 7:06PM UPDATE...Canadian Radars shows an area of showers approaching the St. Lawrence River Valley in Quebec. This area will slowly drift towards the North Woods in the Maine/Quebec Borderlands. Cannot rule out an isolated lightning strike so made some minor tweaks to the overnight POPs and thunder chances. Additionally, adjusted sky conditions based on the latest satellite imagery. There is smoke aloft that continues the very milky skies. HRRR/RAP smoke models continue to indicate the possibility of near surface smoke tomorrow afternoon along the pre-frontal trough. Confidence remains low on if this will result in visibility reduction so opted to not put smoke into the forecast just yet. Also models continue to mainly confine this smoke across Northern 1/3rd of the CWA. Will continue to monitor those trends.

- 00z TAF UPDATE...See discussion below for an update.

KEY MESSAGES

1) Wildfire smoke will remain over the area today leading to milky skies, in areas not overrun by high clouds. Small chance in smoke mixing down toward the surface on Thursday afternoon over the north.

2) Increasing heat and humidity today through late week, with a chance of thunderstorms Thursday and Friday.

DISCUSSION

KEY MESSAGE 1...Wildfire smoke will remain over the area today leading to milky skies, in areas not overrun by high clouds. Small chance in smoke mixing down toward the surface on Thursday afternoon over the north.

KEY MESSAGE 1 DESCRIPTION... Wildfire smoke aloft continues to approach from the northwest late this afternoon into tonight. A milky appearance to the sky could be present over the area through the day on Thursday. There are some indications that smoke could begin to mix down towards the surface Thursday afternoon with a pre-frontal trough entering the north per 12z HRRR and RRFS.

KEY MESSAGE 2...Increasing heat and humidity today through late week, with a chance of thunderstorms Thursday and Friday.

KEY MESSAGE 2 DESCRIPTION... A pre-frontal trough will approach the area tonight. An area of showers will likely move into the north and west during the evening. Showers will continue to push southwards through Thursday afternoon, spreading across the Downeast region. Given marginal instability present along the trough, cannot rule out isolated thunderstorms in the Bangor and Downeast regions by mid to late afternoon. Above normal temperatures will continue as well, with temperatures prior to the trough lifting into the upper 80s throughout the Bangor and Interior Downeast regions. Behind the pre-frontal trough, the north will likely remain warmer than average, with highs lifting up to around 80 under continued southwest warm air advection. Temperatures may not lift as high should upper level smoke trend thicker into Thursday afternoon, blocking incoming solar radiation.

It looks like the greater threat of storms will be on Friday from Bangor to the coast. However, timing of frontal passage is still uncertain and this will determine how far north storms set up. A slower frontal passage may means storms could fire off around noon in northern and central areas but a faster passage may mean storms are mainly confined to southern areas. Guidance is still showing both solutions but generally leaning towards the latter. Cannot rule out a strong storm for Thursday or Friday, however the bigger threat looks to be locally heavy rainfall out of any storm that develops.

AVIATION /00Z THURSDAY THROUGH MONDAY/

00z TAF UPDATE...

Tonight...Mainly VFR, though cannot completely rule out patchy coastal fog at BHB. Brief MVFR cigs are possible from KPQI northwards late tonight as rain showers move through. S to SW winds 5kts or less.

Thursday...VFR/MVFR possible in showers and isolated -tsra. Added PROB30 to HUL and BGR where confidence is slightly higher. Winds shift W behind a frontal passage at 5 to 10 kts.

Thursday night....VFR/MVFR in rain showers. Winds light and variable.

Friday...VFR/MVFR in showers and tstms, especially at southern terminals. NW winds 5-15kts.

Friday Night-Saturday...VFR. NW wind 5-10 kts, gusts to 20 kt.

Saturday Night-Sunday...VFR. N-NW winds around 5kt.

Sunday Night...VFR. Light and variable winds.

Monday...VFR except possible MVFR in any showers/tstms at northern terminals. SW winds 5 to 10 kts.

MARINE

Seas will remain below 5 ft over all waters, with wind gusts remaining below 25 kts all waters through Thursday night. Showers and possibly a thunderstorm over the waters Thursday night into Friday. Patchy fog could reduce visibility tonight and Thursday night. Winds/seas below SCA conditions this weekend and Monday with just some passing clouds.

CAR WATCHES/WARNINGS/ADVISORIES

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