National Weather Service New York NY
745am EDT Thu May 23 2024
Synopsis
A slow moving cold front will move through the area today and tonight, moving offshore early Friday morning. Weak high pressure builds in Friday and remains Friday night. High pressure moves over the region Saturday. A cold front moves through Sunday, moving back north as a warm front Monday. A cold front moves through Tuesday with dry conditions expected by mid-week.
Near Term - Until 6pm This Evening
Only minor adjustments made for current conditions. Showers and thunderstorms were approaching the area from eastern Pennsylvania/western New Jersey.
A slow moving cold front was across western upstate New York and extended into northwestern Pennsylvania and into northern Ohio, with a prefrontal trough across central Pennsylvania into western Virginia. This front was associated with a low over southeastern Canada that will move little through today as the front become more parallel to the low and mid level flow. A warm and humid airmass was in place ahead of the cold front, as dew points have increased into the lower and mid 60s. The area will become increasingly unstable early this morning as daytime heating begins. From central New Jersey through the lower Hudson Valley and into southwestern Connecticut surface based CAPE increases to 1000 to 1500 J/kg and instability lowers with the lifted index around -2. Lift with the front is rather weak, however a few isolated stronger thunderstorms will be possible. And with low level lapse rates increasing with deeper mixing, and soundings developing inverted V, stronger, to marginally severe storms could produce strong and gusty winds, along with hail. The Storm Prediction Center has kept a marginal risk for severe weather today, with damaging winds and hail the primary threats. However, with the isolated nature of the storms, and the marginal risk have not included enhanced wording with the thunderstorms. The CAMs are indicating that the storms will be early in the day, and generally followed them for the probabilities. Then with the activity this morning, additional destabilization will be difficult later this afternoon and into early evening, and have lowered probabilities to slight chance and removed the mention of thunder.
Short Term - 6pm This Evening Through Friday Night
The cold front slowly moves to the south this evening through tonight and passes south Friday morning. Little precipitation is expected with the front after this evening, and will be mainly to the south, ahead of the front, so have gone with a dry forecast later this evening and through tonight. Ridging amplifies to the west tonight and the ridge moves slowly into the region Friday into Friday night as weak surface high pressure builds to the west.
Long Term - Saturday Through Wednesday
Key points:
* Above normal temperatures on Sunday transition to near or slightly above normal Monday through Wednesday.
* Rather unsettled during this time frame with multiple fronts affecting the area.
Zonal flow aloft for Saturday, though there are some model differences with the potential for a weak cut off low over Virginia to head toward the region as advertised by the 00Z GFS. This low This low weakens into a trough as it moves toward the area late Saturday afternoon into Saturday night.
A cold front approaches later Saturday night and moves through Sunday morning, bringing a chance for light showers.
Strengthening low pressure over the western Great Lakes region heads northwest into Canada on Monday, sending the cold front that moved through on Sunday back north as a warm front. A period of unsettled weather is then expected from Monday through Monday night as the warm front, then cold front move through the region. A period of moderate to briefly heavy rain is possible Monday night in association with the cold frontal passage. However, given uncertainty this far out, did not mention in the forecast just yet. The area looks to get dry slotted for Tuesday, cutting off precipitation, though condition could get breezy as the low continues to strengthen somewhere over the Great Lakes region or southern Canada, depending on the model. Dry conditions continue into Wednesday.
Above normal temperatures Sunday will trend closer to normal to slightly above normal for the remainder of the long term period. Monday temperatures may be a couple of degrees to high if more in the way of clouds and rain occurs, as is advertised by the ECMWF (European Centre for Medium-Range Weather Forecasts) and Canadian models.
Marine
Sub-SCA (Small Craft Advisory) conditions are expected across the forecast waters today through Monday night.
Hydrology
No hydrologic impacts are expected today with rainfall of 1/4 to 1/2 inch, with locally higher amounts possible in heavy rain with thunderstorms.
No hydrologic impacts are expected tonight through the middle of next week.
NOAA New York NY Office: Watches - Warnings - Advisories
CT...None. NY...None. NJ...None.
Marine
None.
