textproduct: Caribou

WHAT HAS CHANGED

- Updated aviation discussion for 12z TAFs.

- Slowed down the progression of rain on Sunday night.

- Added patchy fog Monday night.

- Confidence increasing in showers in the north Tuesday evening.

KEY MESSAGES

1) Widespread soaking rain from tonight into Memorial Day. This could aid in mitigating ongoing drought conditions across portions of the region.

2) Showers likely with possible thunderstorms late Tuesday afternoon and Tuesday evening over Northern Maine.

3) Cooler temperatures expected later in the workweek, with unsettled weather likely continuing.

DISCUSSION

KEY MESSAGE 1...Widespread soaking rain from tonight into Memorial Day. This could aid in mitigating ongoing drought conditions across portions of the region.

KEY MESSAGE 1 DESCRIPTION... Ridge axis and dry air will be exiting to the east on today. As the airmass moistens, rain is expected to begin late this evening to early tonight. The rain will then spread from W to E through the night and into Memorial Day. Cold air damming overnight will essentially split the rain between south and north early in the overnight hours before moisture converges over the CWA.

A cold front will cross the area during the day on Memorial Day, bringing a wetting rain across the region. Total rainfall amounts will be highest along the coast as a coastal low develops along the surface trough, enhancing forcing along the coast. Even still, total rainfall will likely remain below an inch through the area, though overcast skies and increased moisture will limit evaporation and add to the surface moisture. Thanks to the recent rainfall and with diminishing winds, patchy valley fog is possible Monday night mainly in valley locations.

KEY MESSAGE 2...Showers likely with possible thunderstorms late Tuesday afternoon and Tuesday evening over Northern Maine.

KEY MESSAGE 2 DESCRIPTION... Confidence is fairly high in a quick hitting system impacting mainly northern portions of the area Tuesday evening. The timing of the shortwave trough approaching from the northwest looks to favor most of the activity being after 6pm, with shower chances peaking in the evening. Thunderstorms are also possible, but confidence is low in this. Rain totals don't look overly impressive, with generally a tenth to a third of an inch of rain north of Millinocket, and little if any from Bangor to the coast. Locally higher amounts are possible in any thunderstorms over the north.

KEY MESSAGE 3...Cooler temperatures expected later in the workweek, with unsettled weather likely continuing.

KEY MESSAGE 3 DESCRIPTION... From Wednesday onward, forecast confidence decreases, specifically in timing individual systems. That said, we do have fairly high confidence in below normal temperatures from Thursday to Saturday, and confidence in a pattern which features unstable north/northwest flow with periodic shower chances. If we can get a clear night, we can't rule out patchy frost mainly in Northern Maine on any of the nights Thursday night to Saturday night. There's about a 25 percent chance that one of the nights in this timerange would have patchy frost.

AVIATION /12Z SUNDAY THROUGH THURSDAY/

Today...VFR for all terminals. S winds 5-10 kts.

Tonight...High confidence in MVFR/IFR developing from S to N for all terminals due to rain and low clouds. SSE winds 5-10 kts.

Monday...MVFR/IFR in rain. Winds SE at 5-10 kt becoming light and variable in the afternoon.

Monday Night...Generally VFR, but with patchy valley fog which could produce local IFR/LIFR. Confidence is low however.

Tuesday...W/SW wind 10 kts gusting 20 kts. VFR, except possible MVFR late afternoon in the far north with potential for storms.

Tuesday Night...MVFR possible from HUL north in showers and possible storms. Likely VFR BGR/BHB. S wind 5 kts.

Wednesday and Thursday...Mainly VFR BGR/BHB and MVFR or VFR HUL/PQI/CAR/FVE. Showers possible. NW wind 5-15 kts with higher gusts during the day.

MARINE

A Small Craft Advisory has been issued late tonight through Monday night due to wind gusts above 25 kts and seas 5-7 ft.

W/SW winds could approach 25 kts late Tuesday to Wednesday, but will most likely stay below 25 kts. Seas 3-5 ft Tuesday/Wednesday, diminishing to around 2 ft Thursday.

CAR WATCHES/WARNINGS/ADVISORIES

ME...None. MARINE...Small Craft Advisory from 5 AM Monday to 8 AM EDT Tuesday for ANZ050-051. Small Craft Advisory from 11 AM Monday to 2 AM EDT Tuesday for ANZ052.