textproduct: Caribou

WHAT HAS CHANGED

-6pm Update: Raised snow chances and PoPs tonight, as models have been dramatically too low for PoPs given the light snow that is still falling everywhere. Kept additional snow accumulations tonight close to the same, though, with 1-3 inches additional accumulation, highest additional toward the New Brunswick border. Also, delayed the ending time of the snow just a touch.

-Added in some light snow showers to the north Thursday night into Friday.

KEY MESSAGES

1) Significant winter storm continues to impact the region through tonight with highest totals across Interior Downeast

2) Chance for colder temperatures this week, with a slight chance of snow showers in the north on Thursday and the weekend.

DISCUSSION

KEY MESSAGE 1... Significant winter storm continues to impact the region through tonight with highest totals across Interior Downeast Maine

KEY MESSAGE 1 DESCRIPTION... The center of the surface low pressure system continues to shift eastward into this evening, passing south of Nova Scotia. Behind the departing low, an inverted trough extends westward into the New England region, sustaining light to moderate snow up through our forecast area through the night tonight.

With profiles remaining within the DGZ across the Interior Downeast region, SLRs continue to run high for this area, often exceeding 25 or 30:1. This fluffy snow will continue to quickly accumulate, even as snow rates taper off through the night. Further north, colder temperatures through the atmosphere pull the profile colder than the DGZ, leading to lower SLRs which are closer to 10:1. Light additional accumulations are expected across the north, but much of the north will only see up to an inch or two of additional snow. Highest snowfall rates this evening will be localized to the trough axis as it moves through the area late, and CAMs guidance suggests there could be local intensification along our eastern border before the trough exits the CWA. All snow is anticipated to end from west to east by around sunrise Tuesday.

KEY MESSAGE 2...Chance for colder temperatures this week, with a slight chance of snow showers in the north and the weekend.

KEY MESSAGE 2 DESCRIPTION... Relatively calm period of weather this upcoming week, as a low pressure moves north into New Brunswick. Manitoba low slides into the Great Lakes region, interacting with aforementioned low in New Brunswick. There is a brief periods of ridging on Wednesday in between this system, with some clearing skies. Clear skies and relatively light winds Wednesday night could lead to some radiational cooling, helping to quickly plummet temperatures, especially in colder valleys. Overnight lows should be 5-10 below zero in the north, and around 0 degrees in the south. Overnight wind chills could be 20 below in the north, and down to 10 below in the South. Rest of the temperatures for the week will be below normal, until a warm up period begins at the end of the week.

Not too much in term of precipitation expected this week. A positively tilted trough forms over Maine Thursday into Friday, which could bring some periods of light snow showers across northern Maine. No significant accumulations anticipated from this, however. Models are hinting at a decent storm moving into the Gulf of Maine at the end of the weekend, but still to early to have confidence in its strength or development. Continue to watch for more updates.

AVIATION /00Z TUESDAY THROUGH SATURDAY/

Tonight - Tuesday...Mainly IFR vis across all terminals in light SN. MVFR cigs will continue through the night, so brief improvements to MVFR are likely periodically through the night in between more moderate snowfall. Vis to improve by 12z as snow moves out, but MVFR cigs are likely to hang around all terminals through the rest of the day on Tuesday. NE winds 5 to 10 kts with occasional gusts to 20 kts at KBGR/KBHB, shifting NW late tonight and remaining NW 5 to 10 kts through Tuesday.

Tuesday night...Cigs improving to VFR from south to north through the night. Winds light and variable.

Wednesday through Wednesday night...VFR/MVFR. W/NW winds 10 to 15 knots with gusts up to 20 knots Wednesday, relaxing to 5 to 10 knots Wednesday night.

Thursday through Friday...VFR/MVFR. A slight chance/chance of snow showers, mostly north. W/NW winds 10 to 15 knots with gusts up to around 20 knots Thursday, shifting to the W/SW at 5 to 10 knots Thursday night. Then 10 to 15 knots Friday.

Friday night through Saturday...VFR/MVFR. NW winds at 5-10kts.

MARINE

Gale warning continues on the coastal waters through the night tonight while SCA remains on the intracoastal waters. Winds taper off through the day on Tuesday. Seas 6 to 10 ft. Moderate freezing spray threat returns overnight across all waters, tapering off to light freezing spray during the day on Tuesday as winds subside. NW winds gusting 20 to 25 kts overnight Tuesday night, and possible moderate freezing spray returning late Tuesday night.

Small Craft Advisory conditions possible Wednesday through Friday night. Light freezing spray Wednesday through Thursday, becoming moderate Thursday night into Friday. Winds from the NW Wednesday, shifting to the west by Friday. Chance for snow showers Sunday.

CAR WATCHES/WARNINGS/ADVISORIES

ME...Winter Weather Advisory until 3 AM EST Tuesday for MEZ001>004. Winter Storm Warning until 3 AM EST Tuesday for MEZ005-006-010- 011-015>017-029>032. MARINE...Gale Warning until 9 AM EST Tuesday for ANZ050-051. Freezing Spray Advisory from 1 AM to 1 PM EST Tuesday for ANZ050>052. Small Craft Advisory until 9 AM EST Tuesday for ANZ052.