textproduct: Caribou

WHAT HAS CHANGED

-No significant changes.

KEY MESSAGES

1) Temperatures rise to nearly 10 degrees above normal Saturday before an Arctic front moves into the area late Sat afternoon. Snow and rain showers occurring ahead of the front, with squalls possible with any snow showers, reducing visibilities.

2) Much below normal level temperatures Sunday and Monday. The coldest temperatures will occur Sunday night into Monday. Temperatures will begin to recover Tuesday into Wednesday.

3) Fast moving low pressure could bring several inches of snow Tuesday night into Wednesday, with the better chances across central and Downeast portions of the forecast area.

DISCUSSION

KEY MESSAGE 1...Temperatures rise to nearly 10 degrees above normal Saturday before an Arctic front moves into the area late Sat afternoon. Snow and rain showers occurring ahead of the front, with squalls possible with any snow showers, reducing visibilities.

KEY MESSAGE 1 DESCRIPTION... The strong cold front will move into the region Saturday morning. Instability with the cold front will produce convective showers in the afternoon. There are two possibilities with these lines of convective showers:

First, the timing of the lines of showers are well ahead of the cold front, allowing for the mixing of warm air into the boundary layer. Due to the afternoon temps being well above normal, reaching into the 40s, any precip that falls would be in the form of rain. The convective showers would have enough moisture from the tropical airmass to create localized heavy rain at times. However, with the mid level being fairly dry, these convective showers could be more scattered to isolated depending on the timing.

Second, the timing of the line of showers would be along the cold front, tapping into the colder air working into the mid levels. Though the surface temps would be well above normal, the 925mb temps would be below freezing. This means any precip that forms in the column above the surface would not have enough time to melt as it reaches the surface. This scenario would create snow showers for the afternoon. This coupled with the gusty winds could produce isolated snow squalls.

Nevertheless, precip is expected for Saturday during the afternoon.

KEY MESSAGE 2...Much below normal level temperatures Sunday and Monday. The coldest temperatures will occur Sunday night into Monday. Temperatures will begin to recover Tuesday into Wednesday.

KEY MESSAGE 2 DESCRIPTION... Arctic air will bring much below normal level temperatures to the region Sunday into Monday. High temperatures Sunday will range from the mid to upper teens north, to the upper 20 to around 30 Downeast. Scattered snow showers will occur Sunday. Low temperatures Sunday night will range from around 10 to 15 below zero north, to around zero to 5 above Downeast. Apparent temperatures could reach Cold Weather Advisory levels across northern portions of the forecast area Sunday night. High temperatures Monday will range from the lower to mid teens north, to around 20 to the lower 20 Downeast. Low temperatures Monday night will range from around 5 below zero north, to around 0 to 5 above Downeast. Temperatures will recover to near normal levels Tuesday, reaching slightly above normal levels Wednesday.

KEY MESSAGE 3...Fast moving low pressure could bring several inches of snow Tuesday night into Wednesday, with the better chances across central and Downeast portions of the forecast area.

KEY MESSAGE 3 DESCRIPTION... Fast moving low pressure will cross the Gulf of Maine Tuesday night into Wednesday. However, timing and track differences still exist. Based on current indications, the better snow chances would occur across central and Downeast portions of the forecast area. Light snow should expand across the region later Tuesday into Tuesday night then persist into Wednesday morning. Dependent on the eventual track, several inches of snow are possible across central and Downeast portions of the forecast area Tuesday night into Wednesday. Hazardous travel is possible Tuesday night into Wednesday.

AVIATION /19Z FRIDAY THROUGH WEDNESDAY/

VFR conditions for all terminals this afternoon and tonight. Light S winds.

Saturday...mainly VFR with brief MVFR/IFR for the north in showers in the afternoon. LLWS for north terminals. S winds 15-20 kts with gust up to 30 kts.

Saturday night...VFR. NNW winds 5-10 kts.

Sunday...VFR/MVFR, occasional IFR, with scattered snow showers. North/northwest winds 10 to 15 knots with gusts up to around 20 knots.

Sunday night...VFR/MVFR north. Isolated snow showers north early. VFR Downeast. North/northwest winds 10 to 15 knots with gusts up to around 20 knots.

Monday through Monday night...VFR. Northwest/west winds 10 to 15 knots with gusts up to around 20 knots Monday. West/southwest winds 5 to 10 knots Monday night.

Tuesday...VFR early. VFR/MVFR late with a slight chance of light snow. Southwest winds 10 to 15 knots with gusts up to around 20 knots.

Tuesday night...VFR/MVFR, occasional IFR, with a chance of snow north. MVFR/IFR, occasional LIFR, Downeast with a chance of snow. Southwest winds 5 to 10 knots, becoming north.

Wednesday...VFR/MVFR, occasional IFR, with a chance of snow early north. MVFR/IFR, occasional LIFR, Downeast with a chance of snow early. VFR/MVFR regionwide during the afternoon. North winds 5 to 10 knots, becoming variable.

MARINE

Seas expected to rise above 5ft late this evening. By Saturday afternoon seas increase to between 5 to 7 feet in southerly swell. Southwesterly winds increase to small craft levels early Saturday morning and remain elevated through the day.

Small craft advisory level conditions Sunday into Monday. A few wind gusts could approach gale levels Sunday night. A chance of snow showers Sunday. Moderate freezing spray Sunday night into Monday. Light freezing spray Monday night into Tuesday.

CAR WATCHES/WARNINGS/ADVISORIES

ME...None. MARINE...Small Craft Advisory from 8 PM this evening to 1 AM EST Sunday for ANZ050-051. Small Craft Advisory from 4 AM to 7 PM EST Saturday for ANZ052.