textproduct: Caribou

WHAT HAS CHANGED

- The risk for thunderstorms Wednesday is likely to be over northern areas, rather than Downeast.

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 over north/central areas Tuesday, continuing into Tuesday night area wide.

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 into the mid 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 over north/central areas Tuesday, continuing into Tuesday night area wide.

KEY MESSAGE 2 DESCRIPTION... The Storm Prediction Center continues to show a 15% risk for severe thunderstorms on Tuesday for all but coastal Maine. Ensemble solutions are in good agreement that a potent shortwave trough will approach our area from the west on Tuesday with a seasonably strong cold front at the surface. Some frontal timing differences still exist among the guidance but the general thinking is that the cold front will move through the Quebec province during the day while convection fires ahead of it in northern parts of our area in response to broad-scale ascent associated with height falls. Then, convection that had developed over Quebec along the front may coalesce into a cluster or MCS and move through our area overnight. The factors driving the chance for severe storms include relatively high instability of 1000-2000 J/kg, strong bulk shear of up to 50 kts, and steepening lapse rates. The question will be how the thermodynamics evolve into the evening and if enough instability can remain to support strong storms persisting as they move through our area overnight. Currently thinking that all severe hazards are possible at this time.

AVIATION /18Z SATURDAY THROUGH THURSDAY/

Rest of this afternoon: VFR. Northwest/north winds 10 to 15 knots with gusts up to around 20 knots.

Tonight: Variable conditions with any patchy fog late. Otherwise, VFR. Variable winds around 5 knots.

Sunday: Variable conditions with any patchy fog early. Otherwise, VFR. Variable winds 5 to 10 knots.

Sunday night: VFR. Variable winds 5 to 10 knots, becoming southwest.

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, 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-Wednesday night: VFR, possible MVFR in any isolated afternoon showers/thunderstorms, especially at northern terminals. WNW winds 10-15 kts with gusts up to 30 kts, decreasing overnight.

Thursday: VFR except for MVFR in any afternoon showers. W winds 10 to 15 kts with gusts up to 25 kts.

MARINE

Winds/seas below small craft advisory levels tonight through Sunday night.

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

CAR WATCHES/WARNINGS/ADVISORIES

ME...Beach Hazards Statement until 8 PM EDT this evening for MEZ029- 030. MARINE...None.