NEAR TERM /THROUGH SATURDAY NIGHT/
A very hot and humid afternoon persists with heat indicies exceeding 100 in numerous locations. Heat Advisories are now in effect for all counties except Carbon and Monroe in PA. Convection is beginning to initiate in and around the I-78 corridor and points north. No changes to the thinking this afternoon and evening with the storms.
With plenty of moisture available and PWats over 2.0" again, locally heavy rain is likely biggest concern, but with the available instability some isolated severe certainly looks possible. Water loaded downdrafts leading to microbursts and locally damaging wind gusts area possible with the strongest cells.

Shower and thunderstorm chances linger tonight as another more pronounced shortwave crosses the area, increasing forcing even as instability decreases. While severe/flood risks likely diminish a bit with loss of heating, will still need to be on guard after sunset for isolated impacts from heavy rain and gusts winds if any more robust cells materialize. Have maintained generally 20-35% PoPs overnight. Aside from the overnight convection potential, it will be a very warm and muggy night, leading to little relief from the daytime heat. Forecast low temperatures will be largely in the mid to upper 70s within the Heat Advisory area, and in the low 70s elsewhere. Some areas of fog and/or low stratus development are possible again, favoring any locations that experience appreciable rainfall.

We are still maintaining a very active Saturday to start off the weekend. A very hot and humid airmass remains in place in combination with an approaching cold front likely brings numerous showers and thunderstorms across the region. Heat advisories are up again for the entire region, minus Carbon and Monroe counties in PA, with heat indicies of 100-105 across the urban corridor north and heat indicies 105+ for the Delmarva and extreme southern NJ. In terms of storms, PWAT values will be in excess of 2 inches across the region, so we are still expecting the main threat to be locally heavy rain with storms. That said, isolated severe storms can't be ruled out given the high CAPE. Guidance is in a bit of a disagreement where the frontal boundary will set up by early afternoon. Wherever it does arrive, we continue to expect numerous scattered showers and thunderstorms to form along and ahead of the front.

Storms will gradually push south and east offshore as the cold front crawls along, though it does look to wash out a bit by early Sunday morning. Some relief with overnight lows cooling to the upper 60s and low 70s behind the front, though dew points will lag a bit in the same region, still leading to a slight cooler, but still rather humid night.

SHORT TERM /SUNDAY THROUGH MONDAY/
Not much change in the short-term forecast through Monday. The cold front still looks on pace to cross the area on Sunday but as it does so, it will be washing out and moving at a snails pace. Ultimately, the front should just leave a remnant boundary behind. As a result, Sunday should be a fairly nice day for most as high pressure builds in from the north and west with just a slight chance of showers across the Delmarva and southern NJ. High temps should again be in the upper 80s to low 90s, but dew points will fall back into the 60s behind the front. At this point, no heat headlines are expected, but if the front hangs up a bit more to the north and west this may need to be reconsidered. Skies should begin to clear out a bit into Sunday night except over the Delmarva where a few showers may linger. Lows will remain though in the upper 60s to mid 70s as moisture content is still quite high.

High pressure will win out on Monday for most areas leading to a mostly tranquil day with a mix of sun and clouds during the afternoon. However, with the remnant boundary lingering overhead and subtle increase in moisture return with dew points rising back into the lower 70s, a few showers or thunderstorms will be possible north and west of the I-95 corridor. As mentioned above, dew points will be slightly higher and air temps will be a degree or two higher as well on Monday. Heat indicies will hover between 95-99 degrees for much of the area. Will continue to evaluate trends amongst T/Td guidance over the next several days in order to determine if any heat headlines will be needed for Monday.

LONG TERM /MONDAY NIGHT THROUGH FRIDAY/
The long term period as a whole is summarized to be quite unsettled with seasonable temperatures. An upper level trough will be over the Great Lakes region Monday night into Tuesday before shifting east over the Northeast US through Wednesday. But this is where the forecast details becomes uncertain because there will be several impulses embedded in the upper flow, allowing several fronts and boundaries to be near our region. This will result in several opportunities for some showers and thunderstorms, mostly in the afternoon and evening hours due to diurnal effects. Right now, the greatest chance for showers/storms looks to be Tuesday into Wednesday. After Wednesday, deterministic and ensemble guidance differs significantly, so have held a chance of showers/storms through the end of next week to account for variability amongst guidance suites.

AVIATION /21Z FRIDAY THROUGH WEDNESDAY/
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY and surrounding areas...

Rest of today (through 00Z)...Prevailing VFR, but some SHRA/TSRA development possible (20-30% chance for I-95 terminals, 40-50% chance for RDG/ABE). Greatest chance for TSRA will be at ABE, where a TSRA TEMPO group has been added. SSW winds 5-10 kts. High confidence in prevailing VFR conditions, lower confidence in storm coverage.

Tonight...Initially VFR, however some areas of fog and/or stratus development are possible again with sub-VFR restrictions. Some isolated showers anticipated between roughly 00-09Z with thunder possible (20% chance). Winds diminish to around 5 kts or less, favoring a southerly direction. High confidence in initially prevailing VFR conditions, but low confidence on the occurrence and timing of any restrictions in fog/stratus/showers overnight.

Saturday...Lingering fog/low stratus in the morning, giving way to VFR by mid to late morning. Intervals of sub-VFR returns with scattered showers and thunderstorms in the afternoon. Low confidence.

Outlook...

Saturday night...Sub-VFR possible. Showers and storms in the evening give way to fog/low stratus developing overnight. Low confidence.

Sunday through Monday night...VFR expected. A slight chance of a shower or thunderstorm possible Sunday night into Monday. Otherwise, no significant weather anticipated.

Tuesday through Wednesday...Sub-VFR conditions possible. A chance of showers and thunderstorms possible with occasional mist/fog.

MARINE
Small craft advisories in effect through Saturday evening.

South winds 15-20 kts with gusts near 25 kts across the Atlantic waters. Seas 4-5 feet build to 4-6 feet Friday night.

Winds and seas remain elevated through the first part of Saturday with showers and storms possible. Winds and seas begin to diminish later afternoon/early evening.

Outlook...

Saturday Night...Winds and seas fall below SCA criteria late evening. Wind gusts to 20 kt. Wave heights up to 5 feet, diminishing to 3 to 4 feet. Chance TSRA.

Sunday through Monday night...No marine headlines expected. Winds generally less than 15 kt and seas of 2-3 feet. A slight chance of a shower or thunderstorm into Sunday night, otherwise fair weather expected.

Tuesday through Wednesday...No marine headlines expected. Winds generally less than 20 kt and seas of 2-3 feet. A chance of thunderstorms expected.

Rip Currents...

The effects of a New Moon today will linger into the weekend. On Saturday, south winds will average 10 to 15 mph with gusts up to 20 mph. With an onshore component in New Jersey, this results in a MODERATE risk for the development of dangerous and life threatening rip currents for the Jersey Shore. Since this direction is a bit more parallel to the coast, if not a bit offshore, in Delaware, this results in a LOW risk for dangerous rip currents at Delaware Beaches.

On Sunday, winds will be lighter and a bit more onshore. This results in a MODERATE risk for dangerous rip currents at the Jersey Shore, mainly south of south of Monmouth county. For Monmouth county and Delaware Beaches, there is a LOW risk for the development of dangerous rip currents.

For specific beach forecasts, visit weather.gov/beach/phi

TIDES/COASTAL FLOODING
With the New Moon to occur today, some locations may see some spotty minor coastal flooding during the next few high tide cycles.

With continuing S/SE flow and the approach of the New Moon, some guidance has areas of Cumberland County NJ seeing advisory minor coastal flooding with the upcoming evening high tide cycle. Though guidance may be running a bit high, a short-fused coastal flood advisory may be needed later on.

CLIMATE
Near record breaking warmest low temperatures are forecast on Saturday. Records for our climate sites are listed below:

Record Warmest Low Temperatures July 6 Site Record/Year Allentown (ABE) 74/1999 AC Airport (ACY) 76/1999 AC Marina (55N) 80/1999 Georgetown (GED) 78/2012 Mount Pocono (MPO) 71/1999 Philadelphia (PHL) 79/1999 Reading (RDG) 75/1934 Trenton (TTN) 76/1999 Wilmington (ILG) 77/1999

PHI WATCHES/WARNINGS/ADVISORIES
PA...Heat Advisory until 8 PM EDT Saturday for PAZ060>062-070-071- 101>106.
NJ...Heat Advisory until 8 PM EDT Saturday for NJZ001-007>010-012- 013-015>023-027.
DE...Heat Advisory until 8 PM EDT Saturday for DEZ001>003.
MD...Heat Advisory until 8 PM EDT Saturday for MDZ012-015-019-020.
MARINE...Small Craft Advisory until 8 PM EDT Saturday for ANZ450>455.