Area Forecast Discussion
Issued by NWS Upton, NY

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000 FXUS61 KOKX 161443 AFDOKX Area Forecast Discussion National Weather Service New York NY 1043 AM EDT Sun Jun 16 2019 .SYNOPSIS... A weakening cold front will approaches and passes through the area late this afternoon into tonight. The front remains close to the region through much of the upcoming week. Several waves of low pressure may move along the front, bringing periods of unsettled weather. && .NEAR TERM /THROUGH TONIGHT/... Most of the showers have ended across the region with just a chance of showers remaining across portions of the lower Hudson Valley this morning as a weakening wave passes through the region. Most of the area likely remain dry until this afternoon as another wave and convectively induced vort max across the Ohio Valley this morning tracks eastward in the near zonal flow. Currently, most of the precipitation will likely move across the southern portions of the region, and may even pass farther to the south late this afternoon into this evening. With the uncertainty of the areal extent and timing of the precipitation have lowered probabilities to likely and chance. With limited surface and elevated CAPE, and marginal instability have lowered the chances for thunder to slight chance. And kept with the current thinking that convection will not continue too far east into southeastern Connecticut and eastern Long Island where the is even more limited CAPE and instability. Also limited the timing from around 18Z to 23Z. The Storm Prediction Center has the southwestern portion of the forecast area in a Marginal Risk. There is a High Risk for rip currents at the ocean beaches today. && .SHORT TERM /MONDAY THROUGH MONDAY NIGHT/... A lull in the precipitation is possible during the day on Monday, before additional showers and thunderstorms potentially develop Monday evening and night. Confidence is low due to a lack of model agreement and consistency. The placement of a residual frontal boundary will determine where the best focus for the rainfall will be. The 00z consensus is that the front remains over the ocean during the day, then comes back northward overnight. A model blend was used for precipitation chances. Temperatures are likely to warm a few degrees with highs in the mid 70s to lower 80s, and lows in the 60s. There is a Moderate Rip Current Risk for Monday. && .LONG TERM /TUESDAY THROUGH SATURDAY/... The main story of the long term continues to surround a nearly stationary frontal boundary that will bring periods of unsettled weather. Confidence in the timing, duration, and any impacts from showers and possible storms still remains low, especially from Monday night through the end of the week. The flow around the base of an upper low/trough across southeast Canada will send several shortwaves/disturbance across the Tri- State, but the timing of these is still not well resolved by the 12z model guidance. These shortwaves in the flow are likely convectively induced and are difficult for models to resolve past 48 hours. Another factor of uncertainty is how much if any of these waves force the frontal boundary further south causing lower precipitation chances. The next potential shortwave and frontal wave may occur into Tuesday. Due to model differences and uncertainty in the strength, placement, and timing of this feature, have capped PoPs at 50 percent on Tuesday. Instability looks weak, but have included mention of a slight chance of thunder. Another possible shortwave and frontal wave may occur on Wednesday. However, the ECMWF is much flatter and weaker compared to the GFS. Interestingly, the deterministic models are progging a more well defined shortwave trough and frontal wave for late Thursday into potentially Friday. This shortwave could leave behind ridging into early next weekend. Will continue to show chance PoPs for mainly showers during much of this time period due to recent model performance in this pattern. Temperatures through the long term will average near to slightly above normal. && .AVIATION /14Z SUNDAY THROUGH THURSDAY/... A weak cold front will slowly move across the terminals this afternoon and evening. Mainly VFR through the TAF period. Showers develop this afternoon north and west of NYC terminals and then move across 21-00z time frame. A thunderstorm cannot be ruled out, but coverage is uncertain so have gone with a VCTS. The activity should weaken a bit as it moves across Long Island and southern Connecticut terminals after 23z. S-SW winds 10-15 kt through the day with gusts 18-23 kt this afternoon. Winds shift towards the W this evening and then NW tonight as the front settles to the south. .OUTLOOK FOR 12Z MONDAY THROUGH THURSDAY... .Mon-Thu...There will be chances for showers and isolated thunderstorms each day, with the better chances Tue and Wed. VFR, becoming MVFR Monday night. IFR possible Tue and Wed. && .MARINE... Winds and seas forecast currently on track. Timing of weather for this afternoon through tonight was adjusted. Otherwise, SCA conds expected today and tonight on the ocean waters, but there may be occasional gusts up to 25 kt along the South Shore Bays this afternoon. Winds subside tonight but seas will remain elevated on the ocean with a swell. Sub-SCA conds then follow through the rest of the forecast period with a frontal boundary stalled near the waters and a relatively weak pressure gradient. Waves of low pressure will move along this boundary, but their timing and placement are uncertain. One of these waves could increase winds on the waters, but overall, conditions should stay below SCA levels into Thursday. && .HYDROLOGY... A frontal boundary approaches today and then stalls over the region through much of next week. Basin average rainfall will total around 1/4 to 1/2 inch through late tonight, with locally higher amounts possible across the lower Hudson Valley into northeastern New Jersey, and metropolitan New York. At this time significant hydrologic impacts are not expected. Waves of low pressure moving along a nearly stationary frontal boundary this week could produce periods of moderate to heavy downpours. The timing, amounts, and any hydrologic impacts remain uncertain. && .EQUIPMENT... NYC NOAA Weather Radio Station KWO35 (162.55 MHz) remains off the air. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...High Rip Current Risk until 9 PM EDT this evening for NYZ075- 080-081-178-179. NJ...None. MARINE...Small Craft Advisory until midnight EDT tonight for ANZ355. Small Craft Advisory until 6 AM EDT Monday for ANZ350-353. && $$ SYNOPSIS... NEAR TERM...19 SHORT TERM... LONG TERM... AVIATION...JC/DS MARINE...JC/19 HYDROLOGY... EQUIPMENT...

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