textproduct: Caribou

WHAT HAS CHANGED

- Added isolated showers to southern Aroostook County early this evening.

- Increased fog along the Downeast coast tonight.

- Further lowered temps on Friday given clouds and backdoor cold front moving in from Canada.

- Lowered temps on Saturday and Sunday given clouds and precip.

KEY MESSAGES

1) Increasingly humid conditions through Friday, with the warmest temperatures focused inland.

2) Cold front approaches Saturday and passes through Sunday into Monday, bringing widespread rain and thunderstorm chances.

DISCUSSION

KEY MESSAGE 1...Increasingly humid conditions through Friday, with the warmest temperatures focused inland.

KEY MESSAGE 1 DESCRIPTION... High pressure strengthening over the Maritimes on Friday will result in strong easterly-southeasterly flow over the CWA tomorrow. This will usher in a backdoor cold front leading to cooler temps especially over eastern/northern portions of the area. With the 7pm forecast update, further lowered temperatures over eastern portions of the area for the day tomorrow. While there is still a huge spread in temperatures among models for places such as Caribou (models show anywhere from 56 to 78 degrees for the 2pm temperature), think that the higher end of these temperatures may be unattainable especially near the New Brunswick border given the backdoor cold front should be through the far east by midday. Showers expected throughout the day in increasing southwest flow aloft and moisture advection. Cannot rule out some thunder chances tomorrow, mainly over wrn zones where there is a better chance for heating. Fog will be an issue tonight into Friday morning for Downeast. Can't rule out some dense fog especially near the coast.

KEY MESSAGE 2...Cold front approaches late Saturday and passes through Sunday into Monday, bringing widespread rain and thunderstorm chances.

KEY MESSAGE 2 DESCRIPTION... A shortwave over the Great Lakes moves into the area Sunday morning. This cold front will bring widespread rain as it moves from west to east, bringing the potential for some embedded thunderstorms that take advantage of some modest CAPE (~100J/kg) and steep mid-level lapse rates ahead of the front.

AVIATION /00Z FRIDAY THROUGH TUESDAY/

Tonight...LIFR conditions in fog and low clouds developing BHB and coastal sites first, then likely progressing north to BGR. Some uncertainty in timing, but BHB appears to go down around 2-5z, and BGR around 5-9z. Once these sites go down to LIFR, they should stay down. Think that Aroostook terminals should stay mostly VFR until about 9-12z Friday, when a cold front moves through from the east and MVFR and possibly IFR cigs develop. Expect Aroostook terminals to stay MVFR and possibly IFR through the day Friday. BGR should improve to MVFR by 15z, though BHB has a good shot at staying IFR all day. Winds tonight will be light, though during the day Friday an E wind around 10 kts will develop mainly at Aroostook terminals.

Friday night...MVFR or lower due to showers, and possible tstms. SE winds 5-10kts.

Saturday...VFR at most terminals, except for some showers and possible tstms at northeast Aroostook terminals. W winds at 5-10kt.

Saturday Night...VFR. Light S winds.

Sunday-Sunday Night...MVFR, or lower, due to rain showers and potential thunderstorms in the morning and day. S winds with gusts 15-20KT possible Sunday. LLWS possible Sunday night. Monday...MVFR in rain showers. S winds, shifting W/SW by afternoon, with gusts 15-20KT possible.

Monday night-Tuesday...VFR. W winds, 5-10KT.

MARINE

Winds and seas remain below 25 kts and 5 ft for all waters tonight through Saturday night, with some fog. May see visibilities reduced in fog throughout the period. A cold front passes through Sunday, with the potential for showers, possibly a thunderstorm, and a few gusts to 25 kt on coastal waters.

CAR WATCHES/WARNINGS/ADVISORIES

ME...None. MARINE...None.