Weather with Bill Evans

National Weather Service New York NY Thursday July 11, 2025 A weak cold frontal boundary will slowly push south of Long Island today into tonight. High pressure then builds in from the north and east going into this weekend. A warm front approaches early Sunday, followed by a cold front approaching Sunday night. High pressure eventually returns early next week, building in through the middle of next week. A slow moving cold front boundary pushes farther south through today. The frontal boundary will also be weakening. Looking aloft, ridging is taking place as a shortwave and its associated jet streak move farther northeast of the region. There won`t be much steering flow. More sun is expected but extra clouds with convection and some easterly component to the flow will limit the high temperature potential. Used a blend of MAVs and NBM, ranging mainly within the 80s, highest across parts of the interior and NE NJ. Without much change in dewpoint, heat indices reach a few degrees higher than the actual temperature. However, they still max out in the lower 90s range, below advisory criterion. With the lack of synoptic forcing aloft tonight, would expect any shower or thunderstorm activity to rapidly diminish this evening with the loss of diurnal instability. Models are showing however some increase in shortwave activity late tonight into early Saturday morning with some increase in upper level winds. Might have a shower or thunderstorm across parts of the interior with otherwise a mainly dry night expected. Light southeast flow at the surface tonight as well as abundance of clouds will help mitigate radiational cooling. Lows forecast tonight will only be ranging mainly from upper 60s to lower 70s. Another round of late night into early morning fog is forecast, but kept more areas across the interior with coverage more patchy elsewhere. HRRR indicated this fog development offshore and moving into the area from the low level southeast flow. For the rest of this weekend, with daytime instability each day, potential for showers and thunderstorms, mainly north and west of NYC. Airmass remains very warm and humid but looks like heat indices still expected to remain below advisory thresholds. A broad mid level trough centered over the Upper Great Lakes translates east into early next week, helping advance a frontal system toward and through the region, bringing increased chances for a more widespread rainfall, especially on Monday ahead of the cold front. Parameters appear at least marginally supportive of thunderstorm development, but steering flow appears progressive enough to mitigate significant flood concerns. Conditions dry behind the fropa into midweek as weak high pressure drifts in and NW flow aloft looks to lower the humidity. Temperatures through the period look to largely stay in the 80s most afternoons thru early week, with a gradual warm up then into mid next week. Not much forcing and absence of a steep pressure gradient keeps conditions below SCA thresholds on all waters through this weekend. Light flow and low seas should then maintain sub Small Craft Advisory conditions on all coastal waters through early next week. Rip current risk is low through Saturday along Atlantic facing ocean beaches with onshore flow 5-10 kt and a 3 ft swell from the southeast at a 7-8 sec period.