textproduct: Caribou

WHAT HAS CHANGED

- Updated Aviation Section for 06Z TAF

- Increased rain chances for Monday

KEY MESSAGES

1) Very warm to hot high temperatures in the upper 80s to low 90s possible Monday-Wednesday. Highest apparent temperatures Tuesday for all but Downeast. Downeast, especially coastal areas should see the highest apparent temperatures Wednesday.

2) There is a chance for strong, to possibly severe thunderstorms area wide on Tuesday, and mainly across coastal Downeast Maine on Wednesday.

DISCUSSION

KEY MESSAGE 1... Very warm to hot high temperatures in the upper 80s to low 90s possible Monday-Wednesday. Highest apparent temperatures Tuesday for all but Downeast. Downeast, especially coastal areas should see the highest apparent temperatures Wednesday.

KEY MESSAGE 1 DESCRIPTION... An upper level ridge over the Great Plains will shift to the east as the jet stream moves across the axis. This will pipe very warm temperatures from the western US into the region Monday through Wednesday. Temperatures are currently expected to peak Tuesday across all inland areas and Wednesday for coastal Downeast. Moderate humidity with dew points in the 60s are expected which should push the apparent temperature higher. As of this update, apparent temperatures could reach into the mid to upper 90s. A cooldown is likely through the end of the week as cooler air moves in behind a cold front expected to exit off the coast on Wednesday.

KEY MESSAGE 2... There is a chance for strong, to possibly severe thunderstorms area wide on Tuesday, and mainly across coastal Downeast Maine on Wednesday.

KEY MESSAGE 2 DESCRIPTION... The Storm Prediction Center continues with the 15% risk for severe thunderstorms on Tuesday for all but coastal Maine. Ensemble models are still in very good agreement with the track and timing of the cold front with the associated low pressure system in north. Several factors are at play that could create the environment for severe storms. First, the upper level ridge over the Great Plains should get pushed southward by the jet stream, causing the warmer temps over the western US to move into the area. Daytime temps on Tuesday are expected to reach into the mid to upper 80s. Next, the surface low pressure system is expected to the intensify throughout Tuesday, creating a strong cold front. In addition, winds are expected to increase at all levels. All of these ingredients should create CAPE values between 1000-2000 J/kg, strong bulk wind shear between 40-50 kts, and steepening lapse rates. The question will be how long the instability will last with the frontal passage. Cannot rule out some possible strong storms lasting into Tuesday night. While the initial threat is for northern and central areas Tuesday, a secondary risk may be possible Wednesday Downeast. Ensemble models do show the bulk wind shear lasting into Wednesday, there is large inconsistency on if the other instability factors will last.

AVIATION /06Z SATURDAY THROUGH WEDNESDAY/

With possible exception of a low end chance for some MVFR/IFR fog early this morning, and again towards the end of the TAF period at KPQI/KHUL/KBHB, high confidence in VFR. Confidence in fog is too low to reflect in the TAFs at this time.

Winds become NW-NNW at just under 10KT throughout by mid morning. All but KBHB should become 10G15-20KT by late morning though late afternoon/early evening when gusts should abate. All terminals should see winds become light and variable by early this evening.

Late tonight-Sunday: Other than a very low chance of MVFR/IFR in patchy fog at KPQI/KHUL/KBHB late at night/early in the morning, High confidence in VFR.

Sunday night: VFR. Light and variable winds

Monday-Monday night: VFR south, MVFR in any showers/thunderstorms at northern terminals Monday afternoon/evening. SW winds 10-15 kts. LLWS possible Monday night.

Tuesday-Tuesday night: VFR, possible MVFR or lower possible in any stronger convection. The best chance for a strong thunderstorm is at northern terminals and the threat could continue into the overnight hours. WSW winds 10-15 kts, becoming W Tue night.

Wednesday: VFR, possible MVFR in any isolated showers/thunderstorms, especially at northern terminals. WNW winds 10-15 kts with gusts up to 25 kts.

MARINE

A light pressure gradient over the waters, and no significant long period swell will limit winds to 10 kt or less and seas to 3 ft or less over the waters out to 60nm through Sunday.

Marginal SCA winds and seas on the coastal and intracoastal waters Monday night through early Wednesday, then decreasing below criteria.

CAR WATCHES/WARNINGS/ADVISORIES

ME...Beach Hazards Statement from 8 AM EDT this morning through this evening for MEZ029-030. MARINE...None.