National Weather Service New York NY
1029pm EDT Monday September 2 2024
Synopsis
High pressure builds into the region thru the middle of the week, gradually moving offshore mid to late week. A complex frontal system affects the region late Friday through Saturday. High pressure returns late Sunday.
Near Term - Until 6am Tuesday Morning
Low to mid 40s dewpoint air making its way slowly across the CWA this evening under light NW flow except at the coast where gusts 20-25kt continue. Forecast remains on track this hour, with only slight adjustments down for dewpoints across the interior. Low temperatures in the mid 40s well north and west of NYC still look good.
Northern stream upper trough axis slides east tonight with a reinforcing Canadian cold front crossing the region this evening.
Scattered diurnal CU + CU along/ahead of secondary cold front this aft/early eve. Gusty NW winds tonight ushering in cooler and drier Canadian airmass. The mixed low-levels should keep temps from radiatively bottoming out, but still lows in the 40s across outlying areas and 50s NYC/NJ metro.
.SHORT TERM /6am TUESDAY MORNING THROUGH WEDNESDAY/... Northern stream upper trough axis slides east Tuesday, with rising height Tuesday Night into Wednesday. A weak shortwave slides into New England on Wednesday.
At the surface, high pressure builds overhead Tuesday into Tuesday Night, and then slides east on Wed. Gusty N winds into Tuesday Am will advect in a cooler/drier Canadian airmass, gradually weakening Tuesday aft. Mostly sunny with temps several degrees below seasonable temps on Tuesday, with highs in the lower 70s interior/ mid 70s city/coast.
Good radiational cooling conds for far outlying areas Tuesday Night. Lows around 40 degrees for far outlying areas, with upper 50s for NYC/NJ metro.
Canadian airmass moderates a bit on Wed, as high pressure slides offshore with return onshore flow. Temps still a few degrees below seasonable with highs in the mid 70s interior/ upper 70s city/coast.
Long Term - Wednesday Night Through Monday
Offshore surface high pressure continues to move east Thursday into Friday. Meanwhile, a northern stream upper trough will be amplifying into the upper midwest and Great Lakes region Thursday through Friday as an area of weak low pressure along the Gulf coast states slowly begins to interact with the northern stream trough. The organizing southern low will interact with the northern cold front Friday into Saturday night. There still remain some differences with the global guidance with the timing and placement of these systems. Trends have gone a little later with this complex since yesterday. However, main impacts still expected for this weekend. A period of moderate to heavy rainfall is possible as the low tracks near or over the region as precipitable waters increases to near 2 inches, and a strong low level jet develops. The low then departs to the northeast on Sunday, and have gone with a dry forecast by Monday morning. This timing is still subject to change.
Temperatures will be near to slightly below normal Thursday and Friday and then trend lower for Saturday into the beginning of next week. Sunday and Monday temperatures may be 5 to near 10 degrees below seasonal normals.
Marine
Northerly wind gusts around 25 kt rapidly develop this evening on the ocean waters, and occasional gusts to 25 kt for remainder of waters ocean waters, on the heels of secondary cold front passage. Wind gusts will subside below SCA (Small Craft Advisory) Tuesday AM. Offshore ocean seas likely remain just below SCA (Small Craft Advisory) at this time.
Winds diminish Tuesday after into night. Thereafter, winds and waves remain below SCA (Small Craft Advisory) criteria through Thursday.
An increasing and persistent easterly flow will allow ocean seas to build to SCA (Small Craft Advisory) levels during Friday. As a complex frontal system impacts the area waters Friday night through Saturday night SCA (Small Craft Advisory) conditions will remain on the ocean waters. There is a chance of SCA (Small Craft Advisory) conditions on the eastern Long Island Sound by late Saturday and into Saturday night as low pressure passes through the region. Conditions slowly improve on the ocean waters Sunday as a northwest flow develops behind departing low pressure.
Hydrology
No hydrologic impacts are expected through the end of the week. There is a chance of moderate to heavy rainfall Saturday into Saturday night with the potential for 1 to 2 inches of rainfall. However, should the coastal system approach along a different trajectory, its possible we may see less rainfall than this.
Tides / Coastal Flooding
Rip currents are expected to be low on Tuesday with generally 1 ft SE and S swells.
Rip currents may increase to moderate later in the day on Wednesday.
NOAA New York NY Office: Watches - Warnings - Advisories
CT...None. NY...None. NJ...None.
Marine
Small Craft Advisory until 8am EDT Tuesday for ANZ350-353-355.
