textproduct: Caribou

WHAT HAS CHANGED

- Aviation has been updated for 06Z update.

- Confidence has increased in gusty winds today.

KEY MESSAGES

1) Strong gusty winds during the day today. Cannot rule out isolated power outages.

2) Locally heavy rainfall possible from Sunday afternoon into Monday morning. Minimal impact on drought expected.

DISCUSSION

KEY MESSAGE 1... Strong gusty winds during the day today. Cannot rule out isolated power outages.

KEY MESSAGE 1 DESCRIPTION... As the strong low pressure system exits to the NE, a large surface high pressure system will move across the Great Lakes and push east. This will cause the pressure gradients to tighten throughout the day today. NNW winds will increase with gusts reaching up to 30 mph. Due to the moist soil and leaves on the trees, there is a possibility of isolated tree damage and isolated power outages.

As the high pressure moves into New England, the pressure gradients will relax. This will quickly decrease winds this evening. Calm winds are expected tonight.

KEY MESSAGE 2... Locally heavy rainfall possible from Sunday afternoon into Monday morning. Minimal impact on drought expected.

KEY MESSAGE 2 DESCRIPTION... A northern stream trough tracks across southeastern Canada from Sunday afternoon into late Sunday night, then crosses Maine from early Monday morning into early Monday evening. At the surface a cold front will approach Sunday, then cross the area Sunday night and Monday morning. This should bring some scattered to possibly numerous showers to the region from late Sunday afternoon into Monday morning. The strongest forcing will be across the North, with that area in the left rear quadrant of a developing 110+ kt upper jet. While surface based CAPE will be minimal, if not non- existent, Showalter indices from late Sunday afternoon into Sunday evening are around 0, mainly across the North, with mid- level lapse rates of 6.5-7 C/km. So some elevated convection, possibly even a rumble of thunder (best chance for the latter is across the North, with the best forcing) is possible.

Precipitable water values should range from 1.25 to 1.5 inches across the North and 1.5 to 1.75 inches elsewhere. This will allow for locally heavy rainfall with any stronger convection. Given the very dry antecedent conditions, other than possibly some ponding of water on roadways, no significant impacts are expected. Also as of now, this is not expected to have any appreciable impact on ongoing drought across the region.

AVIATION /06Z FRIDAY THROUGH TUESDAY/

Today-Saturday...VFR for all terminals. WNW winds 10-15 kts with gusts up to 25 kts today. Then light and variable winds tonight. Then S winds 5-10 kts Saturday.

Saturday night-Sunday morning...MVFR or lower possible, mainly after midnight. LLWS possible. S-SW winds G15-20KT possible Sunday morning

Sunday afternoon-Monday morning...MVFR or lower likely, becoming VFR by late Monday morning. A slight chance of thunderstorms late afternoon/early evening. LLWS possible Sunday afternoon/evening. NW winds G15-20KT possible late Sunday night/Monday morning.

Monday afternoon-Tuesday...VFR, except for MVFR or lower possible in any patchy fog late Monday night. NW winds G15-25KT possible Monday afternoon.

MARINE

Winds and seas will remain below SCA levels today through Saturday. Breezy WSW winds today, then decrease tonight and shift to the NW. Seas 1-3 ft.

Sustained winds of 15 kt or less, gusts of 20 kt or less, and seas of 4 ft or less are forecast for all waters from Saturday night through Tuesday.

CAR WATCHES/WARNINGS/ADVISORIES

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