####018004131#### FXUS66 KSGX 062002 AFDSGX Area Forecast Discussion National Weather Service San Diego CA 102 PM PDT Mon May 6 2024 .SYNOPSIS... Dry and warmer, with gusty winds from the west over the mountains and into the deserts today and Tuesday. A brief bout of offshore winds will occur Wednesday, leading to additional warmth west of the mountains. Another gradual warming trend looks likely heading into this weekend, with no precipitation in the foreseeable future at this time. && .DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE... SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO COUNTIES... The cold low pressure system responsible for this past weekend’s cool, breezy, and wet weather will continue pushing eastward across the Rockies today as high pressure slowly nudges inland from over the Pacific. Accordingly, the onshore flow will weaken, setting the stage for a notably warmer day than yesterday. Highs today look to climb 5-10 degrees warmer than yesterday’s at the coast, about 10-15 degrees warmer across the inland valleys as well as both the High and Lower Deserts, and upwards of 15-20 degrees warmer across the mountains. The warming trend generally continues, albeit just by a few additional degrees, through Tuesday afternoon for most locations. The marine layer will gradually become more and more shallow during this time with low clouds and fog sticking closer to the coast and western coastal valleys. There will still be gusty onshore winds over the mountains and into the deserts in the afternoons and evenings both today and Tuesday. With a weaker pressure gradient, the winds will accordingly be weaker than yesterday. A weak low pressure system passing through the Great Basin Tuesday and Tuesday night will strengthen the pressure gradient again. With all this in mind, wind gusts of 40-50 mph can be anticipated below mountain passes and through wind-prone canyons during the traditional late afternoon and evening hours. The development of a very strong upper level low pressure system over the Northern High Plains, and its influence expanding westward as it strengthens, will cause a quick bout of offshore flow on Wednesday. It will drop temperatures in the deserts by a few degrees but will continue the warming trend for areas west of the mountains. The offshore flow itself does not appear to be overly impactful, with perhaps a few gusts of 30-35 mph in the Santa-Ana-favored areas below passes and through canyons. The forecast then gets a bit more murky from Thursday onward. The aforementioned strong upper low will cause a larger-scale troughing pattern to set in over SoCal. This will support a deeper marine layer with clouds and fog extending farther inland. Temperature trends during this time look to be highly dependent on marine layer coverage and duration of low clouds each morning/afternoon. Eventually the low and attendant trough look to weaken which would support another gradual warming trend, though exactly when that will take place appears uncertain at this time. && .AVIATION... 062030Z...Coasts/Valleys/Foothills...Mostly clear conditions with unrestricted visibilities through this evening. Areas of low clouds to redevelop in coastal areas after 06Z into Tuesday morning, with bases around 1200-1800 feet MSL. Expect low clouds to last until around 16Z with rapid clearing and unrestricted visibilities with the breakup of the marine layer. Mountains/Deserts...Mostly clear conditions with unrestricted visibilities will prevail over the next 24 hours. && .MARINE... No hazardous marine conditions are expected today through Friday. && .SKYWARN... Skywarn activation is not requested. However weather spotters are encouraged to report significant weather conditions. && .SGX WATCHES/WARNINGS/ADVISORIES... CA...None. PZ...None. && $$ PUBLIC...Adams AVIATION/MARINE...Suk ####018006872#### FXUS61 KPHI 062003 AFDPHI Area Forecast Discussion National Weather Service Mount Holly NJ 403 PM EDT Mon May 6 2024 .SYNOPSIS... Overall a very unsettled pattern in place this week. A cold front approaching from the west will work its way through the region tonight before becoming nearly stationary south of Delmarva. Low pressure tracks along the front late tonight through Tuesday morning. Another area of low pressure passes through the region on Wednesday followed by a stronger low on Thursday. A cold front passes through on Friday. Several disturbances are possible this upcoming weekend. && .NEAR TERM /THROUGH TUESDAY/... A cold front will slowly slide south across the forecast area tonight. With the best Omega and RH across the southern half of the forecast area, PoPs will be highest here for the overnight. Showers can be expected with embedded thunderstorms. As alluded to, most of the rain should be confined to areas south of Philadelphia, but can't rule out a few showers as far north as the I-78 corridor. As for rainfall, a quarter to a half inch of rain can be anticipated down around southern New Jersey and Delmarva. Although there is a cold front expected tonight, fog is once again in the forecast, and it could be dense in spots. Drier air will be slow to move in and there is very little wind accompanying the front. Overnight lows will be in the lower 50s to lower 60s. Weak low pressure will be just east of Delaware Tuesday morning. This will keep showers and isolated thunderstorms in the forecast through at least the daybreak hours. Showers and thunderstorms are expected to decrease by lunchtime as low pressure moves offshore. PoPs won't be zero for the remainder of the day, but the most widespread precipitation should be in the morning. Afternoon highs will be in the 70s. Another area of low pressure will track from the Great Lakes into the Ohio Valley. A warm front extending out from that system will lift towards southwest portions of the forecast area later in the day. && .SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/... Another area of low pressure will track from the Great Lakes into the Ohio Valley. A warm front extending out from that system will lift towards southwest portions of the forecast area Tuesday night. Scattered showers and thunderstorms will develop in the evening and then become likely for most of the region after midnight Tuesday night and into Wednesday morning as that warm front lifts through the region. Precipitation tapers off by midday Wednesday, and then a warm and humid airmass will be in place. Highs top off in the mid to upper 80s, except for the low 80s in the southern Poconos and northern New Jersey, and in the 70s along the coasts. Surface dew points will be in the upper 50s to low 60s in the afternoon. Low pressure approaches from the west Wednesday night, and scattered showers and isolated thunderstorms will move into portions of southeast Pennsylvania and Delmarva late Wednesday night. As the main surface low tracks towards western New York and Pennsylvania, a secondary low will develop out ahead of this primary low, resulting in more widespread showers with scattered thunderstorms moving into the region Thursday afternoon and evening as a warm front lifts north of the region. Global guidance has indicated some instability as the warm front lifts north, suggesting the potential for some strong to severe thunderstorms south of the warm front during the afternoon, but exactly how far north the warm front progresses will greatly determine the coverage of any strong to severe storms in our forecast area. At the moment, it remains too uncertain to mention anything more specific at this time. Even the afternoon high temperatures will be highly variant on where the warm front ends up, with low to mid 60s north of the front and mid to upper 70s south. Showers and storms will taper off Thursday night as the storm system shifts offshore. && .LONG TERM /FRIDAY THROUGH MONDAY/... A cold front will push through the region Friday afternoon and evening. Yet another round of scattered showers and isolated thunderstorms will affect the area during that time. Behind the cold front, surface high pressure builds east. Several weak disturbances may touch off some afternoon showers on Saturday and Sunday. Highs will then be in the 60s for southeast Pennsylvania and New Jersey and in the low to mid 70s in Delmarva on Friday. Below normal highs expected for Saturday and Sunday, generally in the low to mid 60s. && .AVIATION /20Z MONDAY THROUGH SATURDAY/... The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG, KMIV, KACY and surrounding areas. Tonight...MVFR/VFR conditions are likely to drop to IFR around midnight or so. Fog is possible once again...and it may be dense. Winds will be light and variable. Higher confidence the terminals see IFR, but lower confidence on how thick or widespread the fog will become. Tuesday...After some IFR in the morning, visibilities and ceilings are expected to rise into the VFR category. Light E to NE winds. Outlook... Tuesday night through Saturday...Sub-VFR conditions at night in fog and stratus, while VFR conditions overall during the day. Chances for SHRA/TSRA throughout the period with sub-VFR conditions. More widespread SHRA with scattered TSRA Thursday afternoon and evening. && .MARINE... Tonight...Sub-SCA conditions expected. Mainly a light south wind with seas 2 to 3 feet. Areas of fog...possibly dense. Tuesday...Sub-SCA conditions expected. Light south winds becoming NE 5 to 10 kts. Seas 2 to 4 feet. Areas of morning fog...possibly dense. Outlook... Tuesday night through Saturday...Overall, sub-SCA conditions through the period. Scattered showers and thunderstorms will result in locally higher wind gusts and seas, with biggest impacts coming on Thursday afternoon and evening. && .TIDES/COASTAL FLOODING... Astronomical tides will be elevated this week with a new moon on Tuesday. Minor tidal flooding and spotty moderate tidal flooding is likely during the high tide cycles starting Tuesday evening and continuing into at least Thursday. Coastal Flood Advisories will be needed. && .PHI WATCHES/WARNINGS/ADVISORIES... PA...None. NJ...None. DE...None. MD...None. MARINE...None. && $$ SYNOPSIS...MJL NEAR TERM...Kruzdlo SHORT TERM...MJL/MPS LONG TERM...MJL/MPS AVIATION...Kruzdlo/MJL MARINE...Kruzdlo/MJL TIDES/COASTAL FLOODING... ####018006244#### FXUS61 KAKQ 062004 AFDAKQ AREA FORECAST DISCUSSION National Weather Service Wakefield VA 404 PM EDT Mon May 6 2024 .SYNOPSIS... Summer-like conditions are expected through the week. Expect hot and humid conditions as well as daily chances for showers and thunderstorms. There will also be multiple chances for severe weather, especially mid to late week. && .NEAR TERM /UNTIL 6 AM TUESDAY MORNING/... As of 355 PM EDT Monday... Late this aftn, sctd showers and tstms were developing over wrn and cntrl portions of the area, due to the combination of a sfc trough, shortwave energy and increasing MLCAPE 1000-1500 J/Kg. Dew points were also in the mid to upper 60s across the region, with temps ranging from the mid 70s to lower 80s. This shortwave energy/trough will push across the area this evening into early Tue morning, resulting in showers/tstms spreading ewrd to the coast. Given the moisture profile (PWATs 1.5"-2.0"), heavy rain will be a good bet in heavier showers or storms. This, combined with portions of the area receiving 1-2" of rain in the last couple of days, has justified placement of a marginal ERO over most of VA (W of the Bay) and inland NE NC. Showers/storms will taper off or end after midnight tonight, lingering the longest over the Eastern Shore. Mild again tonight with lows in the lower to mid 60s. && .SHORT TERM /6 AM TUESDAY MORNING THROUGH THURSDAY/... As of 355 PM EDT Monday... Multiple rounds of shortwaves in a varying flow aloft plus a lee trough and the approach of a cold front, will lead to off and on shower/storm chances Tue through Thu. These will likely follow a generally diurnal pattern with the best chances in the aftn through late evening. Increasingly warmer conditions are expected for Tue and Wed, with highs ranging from the mid 70s to mid 80s Tue, and in the mid 80s to around 90 Wed. Not as warm on Thu with highs mainly in the 80s. Summer-like heat and humidity will ensure presence of instability all three days. A ridge briefly builds just to the W of the region on Tue, placing the local area in NW flow aloft. There does look to be increasing shear, so cannot rule out severe weather. The SPC has placed areas W of the bay in a marginal risk for Tue. The flow aloft then turns back to the WSW for Wed and strengthens, which will allow shear to continue to grow. Thus, there is also a marginal risk on Wed. A cold front will move towards the region Thu, as flow aloft further strengthens ahead of a trough. Ahead of the front, (quasi) linear convection is likely to pass through the FA. While there is still some uncertainty, Thu has the potential for the highest coverage of severe storms this week. && .LONG TERM /THURSDAY NIGHT THROUGH MONDAY/... As of 355 PM EDT Monday... Showers/tstms will exit out to sea Thu night, as a cold front pushes to the coast. Then, a secondary front and upper trough will push across the region Fri through Fri evening, producing the chance for more showers. Lows Thu night in the upper 50s to mid 60s. Highs on Fri mainly in the lower to mid 70s. The weekend looks to be considerably drier, but will keep a slight to small chance of showers (isolated thunder) for Sat aftn through Sun. Dry air also means lower humidity with dewpoints dropping into the 40s-50s. Just below normal to normal temps expected for Sat through Mon. Highs will be in the lower 70s Sat, in the lower to mid 70s Sun, and in the mid to upper 70s Mon. && .AVIATION /20Z MONDAY THROUGH SATURDAY/... As of 230 PM EDT Monday... MVFR to VFR CIGs were prevailing at the TAF sites this aftn, with VCSH mentioned in all TAF sites expect SBY until 20-21z. Sctd showers and tstms will affect all TAF sites from later this aftn through this evening. Heavy rain may impact VSBYs at times, with mainly VFR or MVFR CIGs. Winds will be mainly SSW 5-10 kt this aftn into Tue aftn, with a few higher gusts possible in any stronger storms through this evening. CIGs will become lower MVFR or IFR tonight into Tue morning, then improve to mainly VFR by Tue aftn. Outlook...A warmer, more summerlike pattern will prevail Tue night through Thu, with chances for storms each aftn/evening. && .MARINE... As of 355 PM EDT Monday... Surface high pressure continues to move further offshore this afternoon, while a stalled frontal boundary remains just north of the local waters. Current conditions are rather benign with west/southwesterly winds around 8-12kt. Waves are 1 foot or less with seas of 2-3ft. This trend looks to persist through Wednesday with winds from the south-southeast to southwest around 10kt. There may be occasional gusts to 20kt keeping conditions below SCA criteria. However, there will be chances for thunderstorms each afternoon and evening, which could produce erratic, strong wind gusts over the waters. Otherwise, southwest winds will gradually increase some ahead of an approaching cold front on Thursday. Models differ in the expected speeds/overall pattern, but will keep an eye on the potential for SCA conditions at least across the Bay Friday/Friday night as winds turn northwesterly behind the front. Rain/storm chances continue through the remainder of the week. && .TIDES/COASTAL FLOODING... As of 355 PM EDT Monday... Some nuisance to localized low-end minor flooding (Bishops Head) will still be possible with the higher diurnal astronomical tides early Tuesday morning and again early Wednesday morning. Guidance suggests the high tide cycle early Thursday morning could see a bit more in the way of low-end minor flooding over the mid/upper Bay - due mostly to astronomical tides climbing slightly by late this week as we approach the new moon phase. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...None. NC...None. VA...None. MARINE...None. && $$ SYNOPSIS...TMG NEAR TERM...TMG SHORT TERM...AM/TMG LONG TERM...AM/TMG AVIATION...TMG MARINE...LKB/JKP TIDES/COASTAL FLOODING...AKQ