textproduct: Caribou

WHAT HAS CHANGED

- Gale Warning has been cancelled. - Winter Weather Advisory has been allowed to expire.

- Updated aviation discussion.

KEY MESSAGES

1) A winter storm is likely Monday into Monday night. Strong, gusty winds with snow is expected with the highest totals and strongest winds over Downeast Maine. Blowing snow also likely.

2) A clipper system is possible Wednesday night into Thursday. Snow may mix with or change to rain in southern areas on Thursday. This has the potential to impact travel, especially during the Thursday morning commute.

DISCUSSION

KEY MESSAGE 1...A winter storm is likely Monday into Monday night. Strong, gusty winds with snow is expected with the highest totals and strongest winds over Downeast Maine. Blowing snow also likely.

KEY MESSAGE 1 DESCRIPTION... A strong low pressure system is expected to develop over the southeastern US and strengthen while moving northeast offshore. The storm will become occluded off the mid-Atlantic coast and reach a maximum intensity south of New England. The storm will pass south of the area along the outer edge of the Gulf of Maine Monday to Monday night with the potential for a strong band of heavy snow over the Downeast region. Looking at the ensembles, there is still some uncertainty on track. The general consensus is for the center of the low to pass just south of Nova Scotia but there is still a spread in members with some showing the low passing closer and some farther offshore. Trends in the track will be crucial to watch as it will determine how far inland the heavy snow will get. A closer track to our area will mean greater snow amounts and stronger winds.

Overall, there is high confidence that the greatest impacts regardless of storm track will be Downeast Monday into Monday night. Current guidance supports snow totals in excess of 6 inches across much of Downeast Maine with the highest totals along the coast. Snow to liquid ratios are expected to remain well above 10 to 1 as a result of a sufficiently cold vertical column which will support dry, fluffy snow. Still, reduced SLRs slightly from the NBM as a strong easterly jet just below the DGZ may contribute to crystal breakup.

Gusty winds are also expected with this storm as strong 850mb flow has the potential to mix down to the surface resulting in gusts up to 35 to 40 mph. This is likely to result in visibility reductions and blowing snow. A chance of blizzard conditions exists with the greatest risk along coastal Downeast where snow rates and winds will be highest. However, this will greatly depend on storm track with a closer system track favoring an increased chance of blizzard conditions and a farther offshore system track favoring a lower chance. Regardless, falling and blowing snow is likely to result in hazardous travel conditions.

KEY MESSAGE 2...A clipper system is possible Wednesday night into Thursday. Snow may mix with or change to rain in southern areas on Thursday. This has the potential to impact travel, especially during the Thursday morning commute.

KEY MESSAGE 2 DESCRIPTION... An upper-level disturbance moving east from over central Canada will result in the development of a modest low pressure system over the Great Lakes region. Models generally show the low tracking through or just north of our area sometime Wednesday night through early Thursday. Ensembles show considerable uncertainty in low track and timing so cannot yet be definitive on how impactful the storm will be but likely will not be as impactful as the Monday-Monday night storm.

The best chance for accumulating snowfall will be in northern areas whereas more southern areas may see a rain/snow mix or a turn to rain depending on how far inland warm air reaches. Generally expecting limited travel impacts, mostly in the north.

AVIATION /12Z SATURDAY THROUGH WEDNESDAY/

Across northern areas, VFR this morning. VFR/MVFR this afternoon through early Sunday, then VFR later Sunday. Across Downeast areas, VFR/MVFR with snow ending this morning. VFR this afternoon through Sunday. North winds 10 to 15 knots with gusts up to 20 to 25 knots today. North/northwest winds 5 to 10 knots tonight. North/northeast winds 5 to 10 knots Sunday.

Sunday night...VFR. NE wind around 5 kt north, 10 kt increasing to 15 kt south.

Monday...VFR, becoming MVFR across the north. MVFR, becoming IFR, and possibly LIFR late, over the south. Increasing NE wind 10 to 15 kt over the north and 15 to 20 kt over the south with possible gusts to 30 kt at BGR/BHB.

Monday night...MVFR, possibly dropping to IFR north and IFR, possibly LIFR, south. Improvement to MVFR late. N/NW wind 10 to 15 kt north and 15 to 25 kt over the south with gusts up to around 30 kts early at BGR/BHB.

Tuesday...MVFR, becoming VFR all sites. NW wind 10 to 15 kt.

Tuesday night...VFR. W wind around 5 kt.

Wednesday...VFR, possibly dropping to MVFR north. SW wind around 5 kt.

Wednesday night...Deteriorating to MVFR, IFR also possible. S/SE wind around 5 kts.

MARINE

Have issued a Gale Warning through 7 AM this morning for much of the waters, with the exception of the intra-coastal waters. A Small Craft Advisory is then in effect from 7 AM this morning through tonight. Conditions generally below small craft advisory levels Sunday, though could begin to approach small craft advisory levels late. On the intra-coastal waters, a Small Craft Advisory remains in effect through 5 PM this afternoon. Conditions then below small craft advisory levels on the intra- coastal waters tonight through Sunday. A chance of snow this morning. Light freezing spray this morning, then again tonight into Sunday morning.

Small craft conditions Sunday night will likely increase to storm conditions on the coastal waters and gales on the intracoastal waters as a strong low pressure system passes offshore. Waves peak at 15 to 20 ft Monday night. Some light freezing spray also possible. Still some uncertainty in how strong winds get and how high waves will be depending on storm track but gales or greater expected. Winds and seas decrease beginning late Monday night/early Tuesday. Winds and seas below SCA criteria by Tuesday night and stay below criteria through Wednesday.

CAR WATCHES/WARNINGS/ADVISORIES

ME...None. MARINE...Small Craft Advisory until 5 AM EST Sunday for ANZ050-051. Storm Watch from Monday morning through late Monday night for ANZ050-051. Small Craft Advisory until 5 PM EST this afternoon for ANZ052. Gale Watch from Monday morning through late Monday night for ANZ052.