019
FXUS61 KOKX 171716
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
116 PM EDT Wed Jul 17 2024

.SYNOPSIS...
A pre-frontal trough will linger nearby today, followed by a
cold front pushing through late tonight into Thursday morning.
The front slows down and lingers just offshore Thursday as high
pressure slowly builds and settles in on Friday. The high will
remain in control through the weekend, with a weak cold frontal
passage possible late Sunday into Monday. A warm front will move
through early next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
A severe thunderstorm watch is now in effect for the entire area, including the marine zones, until 800 PM EDT. One more hot and very humid day on tap across the region. The main question is how much cloud cover there will be for the morning and early afternoon. However, this may not be as much of a factor as it typically is with regard to the severe weather risk for very late in the afternoon and evening. With the air mass so anomalously humid, any breaks of sun will be enough with forcing beginning to increase late in the day and evening. The limiting factors regarding a widespread severe weather threat are marginal mid level lapse rates with some warmer air aloft, and marginal bulk shear. Guidance is suggestive of 0-6 km shear values of 30, to perhaps 35 kt. Broken line and multi-cell clusters are the primary expected storm modes. Although a marginal supercell cannot be ruled out. The main hazard with any storm will be strong to damaging wind gusts. The Storm Prediction Center continues with a Slight risk for a good portion of the area, with only the eastern 3rd of the region (Central and Eastern LI and Eastern CT) under a marginal risk of severe weather. There should be no shortage of instability with MLCAPE values likely to range from 1500 to 2000 j/kg, DCAPE values of 800 to 1000 j/kg, and LI values of -5 to 8. With respect to timing, convective allowing models are alluding to 20-21z for convective initiation for western sections to as late as 0-2z for eastern most sections. Heat headlines continue for one last day. With dew points mainly in the lower half of the 70s, and max temperatures expected to reach close to 90 for CT and Central and Western LI, and lower and middle 90s across the NYC metro, NE NJ and far southern portions of the Hudson Valley. This should correlate to heat index values of 95 to 100, with some 100 to 105 values across metro NE NJ. These values could end up slightly lower with enough cloud cover. Overall the expectation is that skies will average out the be partly cloudy for the late morning and early afternoon. The front is expected to slow some and gradually push east tonight. Once the environment gets worked over and severe convection should cease with leftover showers and any convection gets stratified. It will remain muggy overnight with lows in the upper 60s to lower and middle 70s.
-- End Changed Discussion --
&& .SHORT TERM /THURSDAY THROUGH FRIDAY/... The real air mass change takes shape during the day Thursday. The front slowly gets further east across the area, and eventually offshore for the afternoon. Dew point readings will slowly get into and fall through the 60s. So still humid, but nearly as oppressive and muggy. Some clouds will linger, especially further east throughout the morning. More sun moves through from the later morning and early afternoon from west to east. Some high clouds will linger into the afternoon, however skies should average out to be mostly sunny for the second half of the day on a NW to W flow. Temperatures will be more seasonable, with daytime maxes in the middle and upper 80s marking the end of the heat wave. Clear skies are expected Thursday night with more comfortable conditions. Dew point readings will get into the more comfortable 55 to 60 range. Most minimum temperatures will be in the 60s. During Friday look for a good deal of sunshine with high pressure beginning to settle into the western part of the area. Another seasonably warm day with mostly middle and upper 80s expected with light winds due to a weak synoptic pressure gradient. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... High pressure settles over the region this weekend with a frontal boundary remaining south of the region. Temperatures this weekend will remain in the middle to upper 80s and lower 90s. Late Sunday into Monday an approaching weakening cold front may pass through the area, but will likely not result in anything other than an isolated shower. At the same time, the aforementioned front stalled offshore will start to make it`s way back north. This front will return unsettled weather to the area with chances of showers/thunderstorms Monday night through Wednesday. && .AVIATION /14Z WEDNESDAY THROUGH SUNDAY/... A pre-frontal trough will linger nearby today, followed by a cold frontal passage late tonight into Thursday morning. The front will slow down and lingers just offshore for daytime Thursday. AM clouds with some TEMPO MVFR cigs at times (mainly KJFK/KISP but in KEWR/KLGA vicinity as well) should scatter by afternoon. Another round of showers/tstms this afternoon, has a better chance of impacting the NYC metro terminals as a cold front approaches. Expect gusty winds, MVFR or lower cond, and heavy rainfall during any storms. While most of the activity should end by 02Z, there will still be a chance of showers later at night. Winds had backed more out of the S-SE this morning at the NYC metros, and think they will be more southerly than originally forecast this afternoon, but still increasing to 10-15 kt with occasional G20-25kt. Winds diminish again tonight to 10 kt or less, and should start to turn a bit more toward the west especially late tonight. ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty... Timing of convection this afternoon may be +/- an hour or so. Potential for 1SM vsby and G40-50 kt in stronger thunderstorms. OUTLOOK FOR 12Z THURSDAY THROUGH SUNDAY... Thursday: Chance of showers with MVFR cond east of the NYC metro terminals in the morning, otherwise VFR. Friday through Sunday: VFR. Detailed information, including hourly TAF wind component forecasts, can be found at: https:/www.weather.gov/zny/n90 && .MARINE...
-- Changed Discussion --
A severe thunderstorm watch is in effect for all the marine forecast zones until 800 PM EDT. Small craft conditions will become more widespread over the ocean waters towards this afternoon and this evening, and continuing for the western ocean through the first half of Thursday, and lasting through Thursday afternoon for the more eastern ocean waters. Sub small craft conditions then return to the ocean Thursday night into Friday as ocean seas settle closer to 3 ft. Sub small craft conditions are expected to persist throughout the weekend and into early next week.
-- End Changed Discussion --
&& .HYDROLOGY... Any strong thunderstorms for late today through this evening are capable of producing localized heavy rain resulting in a limited risk of flash flooding, mainly of the localized urban and poor drainage variety in any stronger storms. The Weather Prediction Center has placed the area in a marginal risk of excessive rainfall for today and early tonight. No hydrologic impacts are anticipated Thursday through the upcoming weekend. && .TIDES/COASTAL FLOODING... A high risk of rip currents will remain through Thursday with seas remaining elevated on a SE swell of up to 8 seconds. && .CLIMATE... Daily record high minimum temperatures for the next couple of days: ...WED JUL 17... Newark: 80/1968 Bridgeport: 77/1968 Central Park: 82/1870 LaGuardia: 79/1999 Kennedy: 79/2013* Islip: 75/2021* * = also in previous years && .OKX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
CT...Air Quality Alert until 11 PM EDT this evening for CTZ005-006- 009-010. Heat Advisory until 8 PM EDT this evening for CTZ005>011. NY...Air Quality Alert until 11 PM EDT this evening for NYZ067>075- 176-178. Heat Advisory until 8 PM EDT this evening for NYZ067>075- 078>080-176>179. High Risk for Rip Currents until 8 PM EDT this evening for NYZ075- 080-081-178-179. NJ...Air Quality Alert until 11 PM EDT this evening for NJZ002-004- 006-103>108. Heat Advisory until 8 PM EDT this evening for NJZ002-004-006- 103>108. MARINE...Small Craft Advisory until 6 PM EDT Thursday for ANZ350. Small Craft Advisory until 6 PM EDT Thursday for ANZ353. Small Craft Advisory until noon EDT Thursday for ANZ355.
-- End Changed Discussion --
&& $$ SYNOPSIS...BC/JE NEAR TERM...JE/MET SHORT TERM...JE LONG TERM...BC AVIATION...BC/BG MARINE...BC/JE/MET HYDROLOGY...BC/JE TIDES/COASTAL FLOODING... CLIMATE...