textproduct: Caribou

WHAT HAS CHANGED

- 9:53PM UPDATE...Blended in more NBM90th percentile for winds/gusts on Thursday evening into early Friday AM across the upslope areas of the Moosehead Region and North Woods west of Baxter State Park. Hi-Res CAMs, NAM and global models showing a well mixed boundary layer tomorrow night up to 4kft where winds are being modeled at 30-35kt. This is resulting in increasing probabilities of gusts greater than 30mph in this region with cold temperatures ranging -5F to 0F have increased confidence in frigid wind chills. Much of this region can expect wind chills to range -26F to -25F tomorrow night into Friday morning so opted to hoist a Cold Weather Advisory for wind chills in Northern & Central Piscataquis County and Northern Somerset County.

- 6:53PM UPDATE...Added scattered flurries over the Moosehead Region into portions of the North Woods. No CBW/GYX echos but webcams verify the presents of flurries with very little moisture in the boundary layer. Additionally, made some adjustments to winds Thursday into Friday on land and over the waters. Added some hi-res CAMs and NBM75th percentile to bump up gusts. Given these changes have increased confidence in Small Craft Advisory criteria on the waters with moderate freezing spray. Have hoisted an SCA for the Coastal Waters from 1PM Thursday till 1PM Friday. On the Intra-Coastal Waters that SCA runs from 4PM Thursday till 7AM Friday. Have hoisted the Freezing Spray Advisory for all the waters from 7PM Thursday till 1PM Friday. For the Small Craft Advisory, northwest winds 15 to 25 kt with gusts up to 30 kt and seas 3 to 5 ft expected. For the Freezing Spray Advisory, moderate accumulation of freezing spray expected.

- Confidence has increased in a few inches of light snow occurring Thursday night in Northern Maine.

- Uncertainty remains higher than normal for what impacts a coastal low will have on Northern and Eastern Maine from Sunday-Monday.

KEY MESSAGES

1) 1-3 inches of snow is likely over Northern Maine Thursday night.

2) Uncertainty remains with a potential noreaster Sunday into Monday. Coastal areas have the greatest chance of significant impacts from strong wind gusts and snowfall.

DISCUSSION

KEY MESSAGE 1... 1-3 inches of snow is likely over Northern Maine Thursday night.

KEY MESSAGE 1 DESCRIPTION... A slightly warmer, moister airmass rotates in from the northeast Thursday afternoon and night, as part of cyclonic flow around low pressure in the Gulf of St Lawrence. This will bring intermittent light snow to Northern Maine Thursday night. As previous shifts have done, we went with higher PoPs and QPF than NBM had, as NBM typically is too dry for scenarios like this. This said, this is not looking like a big event by any stretch of the imagination, and will be limited to areas from roughly Greenville/Millinocket/Danforth north. The highest snow totals will likely be up toward the St John Valley, where we can't rule out a few places getting up around 3 or 4 inches. Generally expecting 1-2 inches for most of the Crown of Maine, though. This will be a fluffy, low water-content snow with snow ratios 20-25:1. There will be west breeze 5-10 mph with the snow, which should be light enough to keep any blowing snow minor and very localized.

KEY MESSAGE 2... Uncertainty remains with a potential noreaster Sunday into Monday. Coastal areas have the greatest chance of significant impacts from strong wind gusts and snowfall.

KEY MESSAGE 2 DESCRIPTION... Models differ in how quickly a closed mid-upper level low diving SE from the midwest to the SE US from Fri-Sat, develops into a cutoff low off the mid-Atlantic coast Sunday. They also differ on how far off the coast this will occur. They all agree that the low then lifts northeast and passes south of Nova Scotia, but how fast this happens is uncertain - with timing ranging from Sunday night to during the day on Monday.

Given the uncertainty have continued to limit pops overland (including the islands off the Maine coast) Sunday-Monday to at most chance - with some guidance shifting the storm track and precipitation shield more to the S/E with this run and some others shifting it more to the N/W. If there is increased confidence in anything, it is that the North is becoming less likely to see impactful snowfall from this system.

Looking at an ensemble of all available model data, Coastal Downeast has around a 50% chance for at least 4 inches of snow, with probabilities of this across the North generally less than 20% for this system.

Depending on the exact track and how rapidly the storm strengthens, you could see strong gusty winds over coastal Downeast as well with gusts of 35-40mph possible near the immediate coast, with gusts of 30mph or less most likely across the North, outside of higher elevations. There is a chance for gusts to right around advisory level Sunday night for the Downeast Coast. Because this is expected to be a dry fluffy snow, these wind gusts could cause issues with blowing snow across coastal Downeast Maine as well.

At this time, with the winds forecast to be offshore, minimal if any impacts from tidal flooding are expected at this time.

AVIATION /02Z THURSDAY THROUGH MONDAY/

Rest of the Afternoon... Intermittent MVFR ceilings from HUL north until 21z or 22z, then clouds dissipating as the sun goes down. VFR Downeast including BHB/BGR. NW winds around 10 kts with gusts 15-20 kts.

Tonight... VFR areawide with W wind around 5 kts.

Thursday... VFR through 18z, then MVFR ceilings becoming possible in the north by 0z, but likely remaining VFR BGR/BHB. W wind 5-10 kts with gusts to 15 kts.

Thursday Night...MVFR likely with IFR possible from HUL north to PQI/CAR/FVE, with light snow. VFR BHB/BGR. W wind 5-10 kts.

Friday: MVFR possible at northern terminals in the morning in any lingering snow showers, otherwise VFR. NW winds G15-20KT possible.

Friday night-Saturday night: VFR. NW-N Winds G15-20KT possible Friday evening. LLWS possible southern terminals Saturday night.

Sunday: VFR at northern terminals, MVFR or lower possibly developing at southern terminals in snow, with the best chance in the afternoon. NE winds G15-20KT possible at northern terminals, NE winds G25-35KT possible at southern terminals.

Sunday Night: MVFR or lower possible at southern terminals in snow, most likely VFR at northern terminals. N winds G25-40KT possible, strongest at coastal terminals.

Monday: Becoming VFR throughout. NW Winds G20-30KT possible.

MARINE

UPDATE...Have hoisted an SCA for the Coastal Waters from 1PM Thursday till 1PM Friday. On the Intra-Coastal Waters that SCA runs from 4PM Thursday till 7AM Friday. Have hoisted the Freezing Spray Advisory for all the waters from 7PM Thursday till 1PM Friday. For the Small Craft Advisory, northwest winds 15 to 25 kt with gusts up to 30 kt and seas 3 to 5 ft expected. For the Freezing Spray Advisory, moderate accumulation of freezing spray expected.

Previous Discussion... Light freezing spray through Thursday, then moderate freezing spray likely Thursday night. Winds pick back up to small craft levels from the NW late Thursday and continue at small craft levels Thursday night, perhaps reaching low end gale levels (about a 50 percent chance). Seas 2-5 ft.

SCA conditions likely on the coastal ocean waters and probable on the intra-coastal waters Friday and Friday night. Moderate freezing spray is also probable on the waters Friday.

A period of sub-SCA conditions is forecast from Saturday into Saturday evening. Gales are possible late Saturday night on the coastal ocean waters with SCA conditions possible on the coastal ocean waters. From Sunday into Monday Gales are likely with gusts to Storm Force possible on the coastal ocean waters, with gales probable on the intra-coastal waters during this time frame.

CAR WATCHES/WARNINGS/ADVISORIES

ME...Cold Weather Advisory from midnight Thursday night to 10 AM EST Friday for MEZ003-004-010. MARINE...Small Craft Advisory from 1 PM Thursday to 1 PM EST Friday for ANZ050-051. Freezing Spray Advisory from 7 PM Thursday to 1 PM EST Friday for ANZ050>052. Small Craft Advisory from 4 PM Thursday to 7 AM EST Friday for ANZ052.