Marine Weather and Tide Forecast for Colchester, CT

KEY MESSAGES
1) Seasonable and dry conditions through tonight.

2) Airmass trending warmer towards late week, becoming hot and humid Thursday and Friday.

3) Showers back in the forecast mid to late week with potential for thunderstorms as well.

4) Weekend into early next week, initially still hot but not as humid. Mainly dry conditions.

DISCUSSION

KEY MESSAGE 1
High pressure will move farther out into the Atlantic.
Seasonable temperatures along with dry conditions expected today. These temperatures will be warmer than yesterday, ranging from the mid 70s to lower 80s. Clouds increase tonight ahead of a low pressure system to the west. Relatively warmer lows result tonight, ranging from upper 50s to mid 60s.


KEY MESSAGE 2
Airmass will be getting warmer and more humid especially towards Thursday and Friday. Overall pattern in mid levels conveys ridging. Wednesday night lows will be warmer than the previous night by several degrees. The area will be getting into the warm sector during this timeframe of early Thursday through Friday. SW flow advects in low level warm air.

Thursday highs mostly upper 80s to lower 90s range across the region with some mid 90s in NE NJ. Friday highs slightly less values with the range, mainly mid 80s to lower 90s across the region. Dewpoints during these days will be in the upper 60s to near 70 degrees, making the air feel quite uncomfortable. The resulting heat indices reach mid 90s to near 100 for maximum during the day for much of the region Thursday and much of the western half of the region for Friday.

The characteristics of this airmass diagnosed by 850mb temperatures rise near 18 to 20 degrees C Thursday into Friday.


KEY MESSAGE 3
Mid level trough moves in Wednesday with a warm front approaching and moving through from the west. Clouds will be abundant and chances of showers will increase. The resulting temperatures will be a little lower compared to the previous day but the airmass will be getting more humid. Chances for thunderstorms will be slight during the afternoon hours.

For Thursday, less mid level forcing present but temperatures will be remarkably warmer with more sunshine, generating more CAPE. There is some positive vorticity advection on a smaller scale late day Thursday into Thursday evening which will have a higher chance of showers and thunderstorms. These could be locally strong to possibly severe with some models indicating a significant amount of CAPE, around a few thousand J/kg of CAPE.
Models have differences in the CAPE and bulk shear 0-6 km AGL near 25-35 kt.

Layer precipitable waters at times approach 2 inches, with potential for heavy downpours with thunderstorms.

A cold front approaching for Friday will make for another chance of showers and thunderstorms.

KEY MESSAGE 4
The cold front may slow down upon its exit for the weekend, potentially lingering some showers, but just a slight chance.

Overall, weekend looks to be mainly dry with lower dewpoints.
Still hot temperatures near 90 for quite a few locations. Max heat indices stay mostly under 90 though.

AVIATION /09Z TUESDAY THROUGH SATURDAY/
High pressure to the south gradually shifts further offshore.

VFR.

Light WSW flow into the morning, though could be more variable at outlying terminals at times. SW-S winds increase to 10-15 kt by early afternoon, and could be a little stronger (15-20 kt) at KJFK with Ambrose jet development possibly enhancing speeds here.
Gusts to around 20 kt at city terminals as well, with an occasional gust possible elsewhere. Any gusts subside in the evening, and SW flow continues into Wed AM, speeds under 10 kt.

...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...

Gusts may be more occasional at times.

Sustained speeds at JFK could briefly reach 20 kt mid to late afternoon.

OUTLOOK FOR 06Z WEDNESDAY THROUGH SATURDAY

Late tonight: VFR.

Wednesday: MVFR or lower possible in showers during the afternoon/evening. Thunderstorms possible, primarily north and west of the NYC metros. SW winds G20kt.

Thursday-Friday: MVFR or lower possible at times w/ chances of showers and thunderstorms in the afternoon and evening.

Saturday: Generally VFR.

Detailed information, including hourly TAF wind component forecasts, can be found at: https:/ www.weather.gov/zny/n90

MARINE
Marginal SCA conditions for western ocean late today into this evening with otherwise sub-SCA conditions through the weekend with the overall synoptic pattern.

Rip Currents...

For today into this evening, the rip current risk for Southwest Suffolk back west through Brooklyn ocean beaches is high. This is due to southerly fetch increasing and building waves to 3 to 4 ft with around 4-5 second period southerly swell as well as southerly winds increasing onshore to near 20 kt during the afternoon. For Southeast Suffolk ocean shorelines today into this evening, waves and onshore winds are expected to be less with a moderate rip current risk for those beaches.

For Wednesday, southwest flow near 10-15 kt is expected along the ocean beaches with main southerly swell of near 3-4 ft with near 5 second period. Rip current risk for ocean beaches Wednesday is moderate.

OKX WATCHES/WARNINGS/ADVISORIES
CT...None.
NY...High Risk for Rip Currents through this evening for NYZ075-080-178- 179.
NJ...None.
MARINE...None.