####018008193#### FXUS64 KBMX 031845 AFDBMX Area Forecast Discussion National Weather Service Birmingham AL 145 PM CDT Fri May 3 2024 ...New SHORT TERM... .SHORT TERM... (This evening through Saturday) Issued at 145 PM CDT FRI MAY 3 2024 Key Messages: - Chances for showers and some thunderstorms will increase through the afternoon, becoming widespread late this evening through much of the overnight hours. - Storm motions are fairly slow with rain rates in excess of an inch per hour, areas that receive multiple rounds of heavy rain could experience ponding or water with limited potential for highly localized flooding. - Patchy fog may develop overnight due to the widespread heavy rainfall. This afternoon. A shortwave trough is positioned over the Lower Mississippi River Valley Region at midday while mid-level ridging was located over much of Florida and the Bahamas. A diffuse thermal gradient was observed in surface analysis across the northern third of the area where a weak boundary remains present. Through the morning and into midday, this feature has acted as a focus for persistent and additional development of shower and some thunderstorm activity. A cold front was analyzed from Northern Michigan that extended southwest across the Mid Mississippi River Valley and further southwest into Northern Texas. Expect rain chances through mid afternoon to continue to be maximized generally north of the Interstate 20 corridor with an additional area for increase across our western counties as activity continues to develop just head of a convective cluster of showers and thunderstorms that continues to move east across much of Mississippi. This activity is moving about 20 mph, which is slow enough to drop heavy rainfall as rain rates are in excess of an inch per hour to our west currently. There will be limited potential for some ponding of water and perhaps localized flooding if an urban or low-lying area experiences persistent or multiple rounds of heavy rainfall over time this afternoon into tonight. From mid afternoon through early evening, widespread showers and isolated thunderstorms will develop and move into the area from the west with the greatest coverage across the northern and western portions of the area. Winds will be from the southwest at 6-12 mph. Highs will range from around 80 far northwest to near 90 far southeast. Tonight. The mid-level shortwave will move over the are overnight, continuing to support showers with some thunderstorms across the northeast and central portions of the area. This activity will become more confined through the early pre-dawn hours on Saturday across our northeast and far eastern counties. With shower activity tapering off in the pre-dawn hours, low- level moisture will be high and some patchy fog is anticipated, especially for areas that receive heavier rainfall this afternoon through late tonight. Winds will be generally from the south to southwest overnight with speeds from 3-6 mph. Low temperatures will be in the lower to mid 60s areawide. Saturday. The mid-level shortwave will move east over Georgia by early afternoon while a weaker shortwave moves over the Mid-South Region toward mid afternoon on Saturday. A surface cold front will move east, extending from near Chicago and extending southwest across the Ozarks and into the Southern Plains by Saturday evening. A few remnant outflow boundaries from previous convection may remain across the area during the day, providing low-level convergence forcing to permit continued chances for showers and some thunderstorms. The better chance appears to be across the northeast half of the area, but at least isolated showers and storms are expected to develop across the rest of the area through the afternoon hours as the pattern remains unsettled with sufficient heat and humidity to support shower and thunderstorm development. Winds will be from the southwest at 5-10 mph. High temperatures will range from the low 80s northeast to near 90 southwest and far southeast. 05 && .LONG TERM... (Saturday night through next Thursday) Issued at 253 AM CDT FRI MAY 3 2024 Weak quasi-zonal flow aloft continues Sunday, with yet another convectively enhanced shortwave/MCV moving in from the Plains during the late afternoon and evening hours. PWATs around 1.8 inches will be favorable for scattered to numerous showers and storms developing with daytime heating, highest chances north. The shortwave appears a touch slower than previously forecast and have raised PoPs Sunday evening. Shortwave ridging in advance of the shortwave trough should allow temperatures to warm into the mid to upper 80s ahead of convection. A deep trough will eject across the Central and Northern Plains Monday with ridging building ahead of it. The prior weak shortwave may still be close enough to some of the northeastern counties to enhance diurnal convection there. The deep trough remains across the north-central CONUS on Tuesday as ridging builds over the Southeast CONUS. Strengthening low-level southwesterly flow will cause efficient mixing and warming temperatures/lowering dew points especially across the southeast half of the area, suppressing convection. But moisture pooling ahead of a stalled frontal boundary may remain sufficient for isolated to scattered convection in the northwest counties. Wednesday and Thursday a trough with a strong positive tilt will extend from the Great Lakes to the Four Corners while subtropical ridging strengthens over the Gulf. The tightening mid-level height gradient between these two features will result in strengthening WSW flow aloft. A quasi-stationary frontal boundary will reside across the Mid-South with several waves of low pressure riding along it. A strong EML will result in a very unstable air mass south of the front with strong deep layer shear as well. An early spring heatwave with near record highs looks likely across the southern counties. Will have to watch any convective disturbances skirting near the northern counties along the northern fringes of the warmer 700mb temperatures given a conditionally favorable environment for severe storms. 32/Davis && .AVIATION... (18Z TAFS) Issued at 1244 PM CDT FRI MAY 3 2024 Clouds will continue to increase from the west and southwest through the afternoon. Showers with some storms will continue to develop across portions of the north and west portions of the area through mid afternoon, potentially affecting our northern terminals through late afternoon. More widespread showers and storms are moving east across Mississippi and will bring widespread chances for showers and storms late this afternoon and through the late evening hours. Lingering showers with a few storms will remain most persistent across the central and eastern counties overnight through late Saturday morning with lower chances to the south and west. 05 && .FIRE WEATHER... Moisture increases today. RH values will fall into the mid to upper 30s in the southeast, with higher values elsewhere. Scattered showers/storms return for Friday afternoon in the north and west and spread east through Saturday. RH values range from 40 to 60 percent Saturday afternoon, lowest values south. && .PRELIMINARY POINT TEMPS/POPS... Gadsden 64 81 61 84 / 70 60 30 60 Anniston 63 82 63 85 / 70 60 30 60 Birmingham 65 82 65 86 / 70 50 30 50 Tuscaloosa 65 86 65 86 / 70 40 20 50 Calera 65 85 65 85 / 70 40 20 50 Auburn 65 85 66 84 / 50 40 30 40 Montgomery 66 87 66 89 / 60 40 20 30 Troy 65 88 64 89 / 40 40 30 30 && .BMX WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...05 LONG TERM....32 AVIATION...05 ####018006052#### FXUS65 KRIW 031845 AFDRIW Area Forecast Discussion National Weather Service Riverton WY 1245 PM MDT Fri May 3 2024 .KEY MESSAGES... - Snow ends this afternoon, with a clearing sky overnight. Patchy fog is possible (20%) for basins and near Casper due to recent moisture (snow). - High pressure Saturday brings warmer temperatures and dry weather. Warmer Sunday. - Gusty south wind Sunday. Gusts 30 to 50 mph for most of the area. Strongest winds over southern Sweetwater County, with high winds (gusts greater than 58mph) likely (80%). Impacts to I-80 and South Pass due to strong crosswinds. - Precipitation moves in Sunday, with widespread precipitation Monday. Snow levels drop to around 6000 feet. Cool and unsettled weather pattern through next week. && .DISCUSSION... Issued at 1238 PM MDT Fri May 3 2024 Snow has been falling across the area this morning as a cold front passes through. As the sun rises through the afternoon, any snow that has accumulated on grass should melt quickly. Clouds linger through the rest of the day, limiting high temperatures today. Many places peak in the upper 40s today, with the Bighorn Basin seeing a few places hit 50. These temperatures are roughly 10 degrees below normal. Any remaining precipitation comes to an end by around 03Z (9pm). As the trough moves eastward tonight, transitory ridging builds in for the weekend. Starting with Saturday, the day brings warm temperatures and a mainly clear sky (a stark difference from today). High temperatures for many reach the mid-to-upper 60s, with a few places hitting 70. A slight breeze develops in the afternoon (10-25 mph gusts), but should otherwise be a good day for any outdoor activities or chores. The high pressure shifts eastward for Sunday as a potent upper-level low swings into the northern California area. This brings a tight pressure gradient, as well as a 100 knot jet positioned into southern Sweetwater County. A strong south wind develops after sunrise, and especially for the afternoon and evening across Sweetwater County, northward into most of the CWA (exception being far northwest Wyoming). Where the exit region of the jet is (southern Sweetwater County), gusts up to 70 mph are possible if the upper levels are able to fully mix down. Shift of tails highlights this area in the 90th percentile. Elsewhere, widespread gusts 35 to 50 mph occur. Being a south wind, roads like I-80, South Pass/Red Canyon, and US-26 will be impacted as strong crosswinds occur. Precipitation chances move into western Wyoming Sunday morning, spreading east of the Divide for the afternoon and evening, with about a 20% chance of thunderstorms. Snow levels begin around 9000 feet Sunday, but drop to roughly 6000 feet through Monday morning. Therefore, lower elevations are expected to receive mostly rain from this system. That upper-level low moves into the Utah/Idaho/Wyoming area Sunday night and into Monday. Winds begin to shift to a more southwesterly direction, decreasing the gusts some from the day, but gusty winds continue through the night, especially from Sweetwater County up through Natrona County. For Monday, the center of the low is projected to move across Wyoming, then traveling northeastward near the Montana/North Dakota border. The GFS and ECMWF vary a bit in placement on this. Widespread precipitation occurs Monday. The heaviest precipitation will be where favored upslope occurs. Currently, this would be for the Bighorn Mountains and Johnson County, but as mentioned, there is still some uncertainty in exact storm track, which could alter where the best precipitation totals are favored. Will need to watch closely the next few days on where models agree on the storm track. The low is slow to move, as ridge over the eastern half of the country keeps it mostly in place. This would keep precipitation chances over the area Tuesday, especially over the northern half of Wyoming. Currently, models are keeping the influence of the low through Friday, so a cool, cloudy, and unsettled next week is in store. && .AVIATION /18Z TAFS THROUGH 18Z SATURDAY/... Issued at 1139 AM MDT Fri May 3 2024 West of the Divide...KBPI/KJAC/KPNA/KRKS Terminals. An upper-level low is rotating through southwest Wyoming late Friday morning. Cold core and added lift will generate scattered snow showers and potentially brief MVFR conditions until around 21Z. In general, terminals remain VFR through the period. Gusty west to northwest wind 15-25kts becomes widespread by mid-afternoon on the backside of the upper low. Wind speeds diminish early this evening and lingering mid-cloud decks give way to a clearing sky. Mountain tops frequently obscured above 10K feet MSL until 01Z/Saturday. East of the Divide...KCOD/KCPR/KLND/KRIW/KWRL Terminals. Moisture axis streaming across central Wyoming coupled with jet energy will support IFR/MVFR at KCPR until 20Z-21Z Friday. Improvement is already being noted at KRIW and KLND where the snow ends and VFR returns between 18Z-20Z Friday. KCOD sees VFR conditions develop during that same time period. Mid-cloud decks will clear between 23Z-02Z Friday evening. A clearing sky and sufficient boundary layer moisture may allow for fog development at KCPR and KRIW between 10Z-14Z/Saturday. This will need to be monitored for inclusion with the next routine TAF issuance. Mountains frequently obscured until 21Z, with tops obscured until 01Z/Saturday. Please see the Aviation Weather Center and/or CWSU ZDV and ZLC for the latest information on icing and turbulence forecasts. && .RIW WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory until 3 PM MDT this afternoon for WYZ015. && $$ DISCUSSION...Wittmann AVIATION...CNJ ####018007254#### FXUS61 KALY 031846 AFDALY AREA FORECAST DISCUSSION National Weather Service Albany NY 246 PM EDT Fri May 3 2024 .SYNOPSIS... High pressure will provide continued dry conditions through tonight. The high will only move slightly east off the coast through Saturday, with a frontal system slowly approaching from the west. Clouds will increase on Saturday, with chances for showers developing west of the Hudson Valley. Showers will become more likely by Sunday as the system tracks east across the area with cool temperatures. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... Just some thin high clouds over most of the region. 12Z area soundings show mixing potential supports current forecasted high temperatures across the region. Just minor adjustments to temperatures and sky cove through this afternoon. PREVIOUS DISCUSSION: A cooler onshore SE flow will keep temperatures cooler than that past few days. Highs will be mainly in the 60s to lower 70s. Upper level ridge axis gradually shifts east of the area tonight, as a weak disturbance approaching from the west slightly flattens out the ridge. High/mid level clouds will increase thicken from west to east, with a few sprinkles possible west of the Hudson Valley. Dry low levels should preclude any measurable rainfall. With mostly cloudy skies lows will be somewhat mild in the mid 40s to lower 50s. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/... Saturday looks to be the pick of the weekend days in terms of mostly dry weather with near normal temperatures. The surface high is forecast to remain positioned off the New England coast, while ridging aloft is re-established across the Northeast. A slow-moving frontal system will continue to gradually inch eastward from the Great Lakes. The front may get close enough to provide enough forcing for scattered showers mainly west of the Hudson Valley during the afternoon. Highs looks to be close to normal ranging from the upper 50s in the higher terrain to upper 60s in valleys. Better moisture(PWAT anomalies increasing to +1 to +2 STDEV) and forcing start to arrive Sat night, especially late in the overnight, as the upper ridge axis breaks down with a stronger short wave moving in from the west. Will mention likely PoPs west of the Hudson Valley and chance east. Lows will be mainly in the 40s to near 50. Southerly flow increases ahead of the front as it advances into western NY on Sunday. Moisture will continue to surge northward ahead of the boundary, with the aforementioned short wave trough aloft moving eastward across the region. This will result in showers likely across the entire area for much of the day. With the clouds/showers around and a persistent low level S-SE breeze, it will be a cool/raw day with highs only in the 50s with even some 40s in the highest elevations. Rainfall amounts generally look to be around 0.50-1.00", with the max focused on the Mohawk Valley and southern Adirondacks. These rainfall amounts will not cause any hydro concerns. The surface front and short wave aloft move into New England Sun night, with showers tapering off from west to east mainly during the evening. At this time it appears the overnight hours should be mainly dry with high pressure building from the west and a developing W-NW flow ushering in drier air. Lows expected to be similar to recent nights with mid 40s to lower 50s. && .LONG TERM /MONDAY THROUGH FRIDAY/... Long term begins at 12z Monday with the cold front departing off to our east. There could be a few lingering showers around during the morning, especially across western New England, but overall we should see a drying trend as we head through the day. Monday afternoon through Tuesday, upper ridging amplifies to our west with upper troughing to our north in southeast Canada. This will lead to upper confluence near our region and allow a ridge of high pressure to build in from the northwest. With large-scale subsidence, Monday afternoon through Tuesday should be dry. With cold/dry advection and deep mixing behind the front, we bumped temperatures up a few degrees above NBM guidance. Highs Monday and Tuesday will range from upper 60s in the high terrain to mid/upper 70s for the valleys. Lows Monday night will be mainly in the 40s to 50s. Tuesday night through Thursday night...A warm front approaches from the southwest Tuesday night or Wednesday, bringing with it a chance for some showers. However, the exact timing of the warm front remains uncertain at this time. Beyond that, we get into a pattern with broad, positively tilted upper troughing over the center of the country and flat upper ridging to our east. This puts our region in an area of deep, persistent SW flow aloft. With an active jet stream to our west/northwest, there will be several disturbances aloft tracking through our area over the middle to end of next week. While it is too early to specifically time out any of these features, Wednesday through the end of next week looks to be unsettled, so will mention chance PoPs for the entirety of the second half of the long term period. Some thunder may be possible depending on the timing of these disturbances relative to peak daytime heating. With persistent southwest flow and warm advection, highs each day will be in the 60s to 70s with overnight lows in the 40s to 50s. The second half of the week also looks more humid compared to Monday and Tuesday. For days 8-14, we may remain in an unsettled pattern with the CPC expecting above normal precip and near normal temperatures. && .AVIATION /19Z FRIDAY THROUGH WEDNESDAY/... VFR conditions prevail at all TAF sites through 06 UTC with light and variable winds. Southeasterly winds will develop after 06 UTC and some low stratus may redevelop but confidence is lower compared to previous nights. We only included TEMPO groups at PSF where confidence was a bit higher. Any early stratus burns off by 12-14 UTC, VFR conditions return with mid and higher level clouds spilling over the terminals ahead of our next approaching disturbance. Light and variable winds become southeasterly by or shortly after 06 UTC sustained around 5kts. South-southeasterly winds continue through the end of the TAF period becoming sustained around 5kts. Outlook... Saturday Night: Moderate Operational Impact. Chance of SHRA. Sunday: High Operational Impact. Likely SHRA. Sunday Night: Moderate Operational Impact. Chance of SHRA. Monday: No Operational Impact. NO SIG WX. Monday Night: No Operational Impact. NO SIG WX. Tuesday: No Operational Impact. NO SIG WX. Tuesday Night: Moderate Operational Impact. Chance of SHRA. Wednesday: High Operational Impact. Likely SHRA...TSRA. && .ALY WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. MA...None. VT...None. && $$ SYNOPSIS...NAS NEAR TERM...NAS/JPV SHORT TERM...JPV LONG TERM...Main AVIATION...Speciale ####018004917#### FXUS61 KILN 031848 AFDILN AREA FORECAST DISCUSSION National Weather Service Wilmington OH 248 PM EDT Fri May 3 2024 .SYNOPSIS... Repeated rounds of showers and thunderstorms are expected through the weekend along with muggy conditions. Additional thunderstorms are possible into the middle of next week. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... Light shower activity may continue late this afternoon/early this evening in the unsettled and weakly unstable environment across the Ohio Valley. While a few thunderstorms cannot completely be ruled out prior to sunset, persistent cloud cover and light rain earlier today has kept instability to a minimum. For the overnight, a weak cold front will attempt to drop in the from the north before stalling over northern Ohio. At most, only expecting a few degree temperature drop as some northeasterly flow tries to develop. However, winds could end up mainly remaining light and variable overnight since weak pressure gradient stays over the region. Some shower chances persist tonight and forecast lows are generally in the 60s. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/... A weak stalled front is expected to lift north of the area on Saturday. Warm, humid conditions will be in place as southerly flow redevelops leading to highs near 80 during the afternoon. Instability should accompany the muggy conditions Saturday afternoon/evening bringing the chance for showers and thunderstorms. If a weak shortwave does end up moving through on Saturday, fairly widespread shower and thunderstorm coverage could develop. Severe chances remain low since shear is weak and DCAPE remains moderate to low in the moist, saturated sounding. Locally heavy downpours are likely since PWATs will be high. Additionally, brief gusty winds are possible in the strongest storms in the this summer-like setup. Shower/storm chances continue on Saturday night due to the possible development of an upper level shortwave and the approach of a cold front to the northwest. Brief, locally heavy rain remains the biggest threat since instability and shear are weak. Southwesterly winds persist along with warm and muggy conditions. && .LONG TERM /SUNDAY THROUGH FRIDAY/... A wet period is indicated as persistent moisture advection couples with waves of low pressure. Relatively slow moving systems will allow showers to linger, with brief dry interludes separating batches of showers. Precipitable water remaining above an inch will be feeding the showers. For Sunday, the first wave of low pressure will be tracking to the Great Lakes, resulting in widespread showers and a few thunderstorms. Much the same can be expected for Monday, though most showers may shift south, closer to a disturbance over the Southern Appalachians. A relative lull in precipitation is forecast for Tuesday as high pressure builds in between disturbances. Two more potent waves of low pressure could impact the region on Wednesday and Thursday. There should be a better chance for severe thunderstorms as stronger winds enhance storm strength and structure. Showers and thunderstorms may linger on Friday as another disturbance crosses the Appalachians. Temperatures are likely to stay above normal through the long term, with some fluctuation with respect to advection around weather systems. Highs will generally be in the mid 70s to low 80s Sunday through Thursday, before readings slip to the upper 60s to mid 70s on Friday under a modest decrease in geopotential heights. && .AVIATION /19Z FRIDAY THROUGH WEDNESDAY/... VFR ceilings and shower activity continue this afternoon before showers diminish in coverage this evening. Thunderstorms are not out of the realm of possibility this afternoon, but the lack of instability keeps TS or VCTS a low probability of occurrence and out of the TAFs. VFR ceilings may lower into the MVFR range after 0600z in areas south of an approaching cold front (KDAY, KILN, KLUK, KCVG). Lowered ceilings, should they form, may persist into the morning although ceilings tend to lift toward late morning with the high sun angle in May. Southwesterly winds may persist for the first part of the afternoon in some locations before becoming light and variable this evening and through the overnight. Southeasterly winds develop after 1200z Saturday. OUTLOOK...Thunderstorms possible at times through Tuesday. MVFR conditions are possible again Sunday morning. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...None. KY...None. IN...None. && $$ SYNOPSIS...Campbell NEAR TERM...Campbell SHORT TERM...Campbell LONG TERM...Coniglio AVIATION...Campbell ####018003684#### FXUS63 KDVN 031849 AFDDVN Area Forecast Discussion National Weather Service Quad Cities IA IL 149 PM CDT Fri May 3 2024 .KEY MESSAGES... - Upper level pattern remains active, with periodic chances for showers and storms through next week. - The Storm Prediction Center has a Marginal Risk (level 1 of 5) for severe storms on Saturday for portions of the area. && .SHORT TERM /THROUGH SATURDAY/... Issued at 145 PM CDT Fri May 3 2024 This Evening and Tonight: High pressure will remain in control leading to light winds and mainly clear skies with lows in the 40s to low/mid 50s far southwest. Saturday: A cold front is forecast to track across eastern Iowa and northwest Illinois during the morning and afternoon. A stronger line of showers and storms moving through western into central Iowa tonight (Friday night) is expected to gradually weaken into Saturday morning as it pushes into a more stable air mass across our western outlook area (with surface dewpoints only in the 40s early in the day). However, some rain is likely as this first wave moves through and have 50-70% chances west of the Mississippi River for the morning hours. Low-level theta-e advection coupled with diurnal heating will allow for the build up of SBCAPE into Saturday afternoon for locations along and east of the Mississippi River. This will coincide with the passage of the cold front and could result in redevelopment of scattered showers and storms between 2 PM to 7 PM, right now favored for eastern counties. Per HREF surface- based CAPE near 1000 J/kg and deep layer shear around 30 kts, the environment may be supportive of a few strong to severe storms which is in line with SPC's Marginal Risk (level 1 of 5). The primary threats are hail and gusty winds. && .LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/... Issued at 145 PM CDT Fri May 3 2024 Another chilly night is expected Saturday night, with lows in the 40s to lower 50s, but Sunday, much like today, appears to be seasonally pleasant in the lower 70s. Global models are in good agreement that a large upper trof will build into the Midwest in the Monday through Wednesday time frame. This should sweep another dynamically supported warm advection band of showers and storms through our area centered on Monday night into Tuesday. The quick flow aloft, and progressive boundary should keep QPF totals from being problematic, with most spots well under 1 inch in the NBM/WPC mean. There is potential for storms to redevelop Tuesday afternoon, but confidence is low on this scenario. SPC has outlooked the area for a slight severe risk, but again confidence regarding the details is low as it will depend on timing and placement of a cold front moving through the Midwest. Stay tuned. Seasonally pleasant temperatures are forecast through Wednesday, with a bit of a cool down by late week, as the upper trof deepens over the Midwest. && .AVIATION /18Z TAFS THROUGH 18Z SATURDAY/... Issued at 1215 PM CDT Fri May 3 2024 VFR will continue today and tonight before a cold front approaches from the west on Saturday. The front will bring MVFR/IFR ceilings and a chance for scattered showers and thunderstorms by the mid to late morning west of the Mississippi River. Held off on thunder mention in the TAFs for now due to low confidence on storm coverage. && .DVN WATCHES/WARNINGS/ADVISORIES... IA...None. IL...None. MO...None. && $$ SHORT TERM...Uttech LONG TERM...Ervin/Uttech AVIATION...Uttech ####018008536#### FXUS61 KLWX 031849 AFDLWX Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 249 PM EDT Fri May 3 2024 .SYNOPSIS... A backdoor cold front will sink south of the area tonight. The boundary will return north as a warm front Sunday into Monday before secondary cold front approaches and stalls near the area for the middle and latter portions of next week. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... High pressure remains centered over the New England Coast this afternoon while an upper-level ridge axis is slowly moving off to our east. An upper-level trough is building over the central CONUS and a backdoor cold front is currently located near the Potomac Highlands into central Virginia. The backdoor boundary will most likely stall out near the area through late this afternoon before eventually pushing off to our south and west tonight as high pressure strengthens along the New England Coast. As convergence strengthens along the backdoor boundary into this evening, this will combine with moisture advection (southerly flow aloft around periphery of the high) and instability, triggering some showers and thunderstorms over the Allegheny and Potomac Highlands into the Shenandoah Valley. This activity will likely advect eastward into the metro areas late this evening and overnight. A rumble of thunder is possible overnight as well due to limited elevated instability above the marine layer. Low clouds and noticeably cooler conditions are expected overnight as the onshore flow continues behind the backdoor cold front. Lows will be in the 50s for most areas, with upper 40s in portions of northern Maryland. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/... The backdoor boundary will remain to the south and west through Saturday night while high pressure remains centered near the New England Coast. An onshore flow will continue during this time while warm and moist air overruns the marine layer in response to an upper-level trough pushing into the Midwest. This will result in plenty of clouds along with periods of rainfall and unseasonably cool conditions. There may be some breaks in the rain, but for most of the time near and west of Interstate 95, there will be some rain around. Perhaps there will be some more breaks east of Interstate 95 where the overrunning moisture may not be quite as deep. The overrunning moisture will deepen Saturday night into Sunday morning as the boundary begins to push north as a warm front, and the low-level flow develops a fetch from the Gulf of Mexico. Therefore, more rain is expected. The warm front will move into the area Sunday while a weak upper-level trough axis passes through. More unsettled conditions are expected with showers and perhaps even a couple thunderstorms. Sunday afternoon will turn out a bit warmer and more humid as well, but temps still near and below climo. Highs will range from the 60s north of the boundary in northern MD into the metro areas/eastern WV/northern VA to the 70s south of the boundary. The upper-level trough axis will move off to the east Sunday night while the surface boundary remains nearby. While a few showers are possible, coverage of precipitation should wane behind the departing trough axis. There may be areas of dense fog overnight with plenty of low-level moisture and light winds. && .LONG TERM /MONDAY THROUGH FRIDAY/... The unsettled weather pattern is likely to continue across the region for virtually all of next week. Nearly zonal flow aloft favors numerous passing shortwaves that bring enhancements to the daily afternoon showers and thunderstorms. Even at night, isolated showers/storms are possible given the increased moisture and lingering elevated instability. At the surface, a stalled frontal boundary is likely to be just north of the area Monday, slide south to around I-70 Monday night, then be pushed back north of the area through mid week. However, any change in the position of the stalled front could result in higher or lower rain chances than currently forecast for some areas. A stronger shortwave trough is forecast to cross the area Wednesday night into Thursday, possibly bringing some heavier rainfall and stronger storms to the area. Afternoon highs in the upper 70s to low 80s Monday and Tuesday warm to the mid 80s Wednesday and Thursday. Very mild overnight lows in the 60s each night due to increased dew points and cloud cover. && .AVIATION /19Z FRIDAY THROUGH WEDNESDAY/... VFR conditions are expected through late this afternoon along with dry conditions. Low clouds will develop due to an onshore flow with MVFR conditions developing most likely between 2 and 5Z and IFR conditions developing overnight. Showers are likely to develop overnight, and a thunderstorm cannot be ruled out between 5 and 9z due to elevated instability. IFR/subIFR conditions are expected most of the time Saturday through Saturday night along with periods of rain and drizzle. There may be a few breaks of MVFR conditions Saturday afternoon. More unsettled conditions are expected Sunday morning with IFR/subIFR cigs/vsbys. Cigs/vsbys should improve some Sunday afternoon, but areas of low clouds and dense fog may cause more subIFR conditions Sunday night. Showers are likely Sunday with perhaps a few thunderstorms. Precipitation coverage should wane Sunday night, but a few showers are possible. Unsettled weather looks to continue for the start of next week. Scattered showers and thunderstorms are likely each afternoon, with more isolated activity during the overnight and mostly dry in the morning. A heavy shower/storm moving over a terminal could result in brief sub-VFR conditions. Outside of shower/storm activity, VFR conditions are expected. && .MARINE... A pressure surge behind a backdoor cold front will cause easterly winds to gust around 20 to 25 knots into this evening. A Small Craft Advisory is in effect. The gradient will subside a bit overnight through Saturday, but an SCA remains in effect over the Bay and lower Tidal Potomac River. It will be marginal though with gusts around 15 to 20 knots. The Small Craft Advisory continues Saturday night for the Bay as well as the middle and lower Tidal Potomac River due to onshore winds ahead of an approaching warm front. The warm front will move into the area Sunday into Sunday night. More SCA conditions are possible during this time. West to southwest winds around 5-10 knots at the start of next week as the unsettled weather pattern continues. Scattered afternoon showers and thunderstorms are likely each afternoon. Any stronger storm could produce wind gusts to 35 knots and lightning strikes. A weak frontal boundary dips south into the northern Chesapeake Bay Monday night, then lifts north of the area Tuesday. Otherwise, winds are forecast to remain below SCA conditions. && .TIDES/COASTAL FLOODING... Onshore flow will persist through early next week. This will raise water levels and keep them elevated during this time, causing minor tidal flooding for many locations. Moderate tidal flooding is possible around Annapolis and St. Mary's County with the high tide cycle late Saturday night, and again late Sunday night into Monday morning. && .LWX WATCHES/WARNINGS/ADVISORIES... DC...Coastal Flood Advisory until 8 AM EDT Saturday for DCZ001. MD...Coastal Flood Advisory from midnight tonight to 5 PM EDT Saturday for MDZ014. Coastal Flood Watch from late Saturday night through Sunday morning for MDZ014. Coastal Flood Advisory from 9 PM this evening to 2 PM EDT Saturday for MDZ017. Coastal Flood Watch from Saturday evening through Sunday morning for MDZ017. VA...None. WV...None. MARINE...Small Craft Advisory until 6 AM EDT Sunday for ANZ530>534- 537>543. Small Craft Advisory until midnight EDT tonight for ANZ535-536. Small Craft Advisory from 6 PM Saturday to 6 AM EDT Sunday for ANZ536. && $$ SYNOPSIS...BJL NEAR TERM...BJL SHORT TERM...BJL LONG TERM...KRR AVIATION...BJL/KRR MARINE...BJL/KRR TIDES/COASTAL FLOODING...BJL ####018004785#### FXUS62 KMFL 031850 AFDMFL Area Forecast Discussion National Weather Service Miami FL Issued by National Weather Service Austin/San Antonio TX 250 PM EDT Fri May 3 2024 ...New SHORT TERM, LONG TERM, MARINE, BEACHES... .SHORT TERM... (Rest of today through Saturday) Issued at 248 PM EDT Fri May 3 2024 A rather benign weather pattern remains in place across South Florida today with continued light to moderate easterly flow with surface high pressure to the east. Southwest Florida has the best opportunity for any isolated showers or weak convection with the sea breeze this afternoon. An upper level disturbance advancing towards and into the Florida panhandle tonight will open a small weakness in the upper level flow across the Florida peninsula from Saturday into Saturday night. This weak upper level disturbance combined with an increase in the moisture profile between 850 and 700 mb should induce some slightly greater PoPs during Saturday afternoon into the 20 to 40 percent range. With the continued moderate easterly flow, this activity will be most favored across the interior/western portions of South Florida. Expect for the afternoon highs to top out in the mid 80s to near 90 degrees. The overnight lows will trend in the low to mid 70s along the coast while interior locations dip into the mid to upper 60s. && .LONG TERM... (Saturday night through next Thursday) Issued at 248 PM EDT Fri May 3 2024 The weak upper level disturbance lingers through Sunday atop the Florida peninsula before becoming more diffuse. The 500 mb heights then increase into mid to late week as upper level ridging will build into the region from the west. Surface high pressure stays focused to the east in the Atlantic, maintaining the light to moderate east to east-southeasterly flow across the region. Like Saturday, Sunday will feature around 20 to 40 percent chance for showers and convection across the interior and western portions portions of South Florida. Early next week keeps some isolated opportunities but solely with any lift from the afternoon sea breeze. The PoPs then look to diminish even more into mid to late next week as the upper level ridge strengthens. The temperatures also respond as afternoon highs could reach the mid 90s across interior locations by Wednesday and Thursday of next week. && .AVIATION... (18Z TAFS) Issued at 107 PM EDT Fri May 3 2024 VFR flight conditions are expected to primarily prevail through the TAF operational period at the local aerodromes. Kept VCSH at KAPF as some isolated showers and/or weak convection across portions of southwest Florida. Light to moderate east to east-southeasterly flow will continue. The only exception is KAPF for a time this afternoon where the flow becomes west-southwesterly thanks to the influence of any of the sea breeze and any isolated showers/weak convection in that region. && .MARINE... Issued at 248 PM EDT Fri May 3 2024 Besides occasional times of gusty easterly winds, anticipate for marine conditions to stay rather benign through the weekend and entering into early next week. Isolated to scattered rain showers and a few thunderstorms are possible each day, which could bring brief periods of rough seas and gusty winds. Seas will generally remain at 2 to 4 feet in the Atlantic waters and 2 feet or less across the Gulf waters. Winds are likely to peak in the 13-18 kts range out of the east and likely induce periods of Small Craft Exercise Caution conditions. && .BEACHES... Issued at 248 PM EDT Fri May 3 2024 Breezy easterly flow will lead to an elevated risk for rip currents along the Atlantic beaches through the remainder of the today and this upcoming weekend. Highest rip current risk today will be maximized across the Palm Beach County beaches. && .PRELIMINARY POINT TEMPS/POPS... Miami 74 84 74 84 / 20 20 10 30 West Kendall 71 85 72 86 / 20 20 10 30 Opa-Locka 73 86 73 86 / 20 20 10 30 Homestead 73 85 73 85 / 20 20 20 30 Fort Lauderdale 74 83 74 83 / 30 20 20 30 N Ft Lauderdale 74 84 74 84 / 30 30 10 30 Pembroke Pines 73 87 73 87 / 30 20 10 20 West Palm Beach 72 84 72 84 / 20 20 10 20 Boca Raton 73 84 74 85 / 40 20 10 30 Naples 71 88 71 89 / 20 40 10 30 && .MFL WATCHES/WARNINGS/ADVISORIES... FL...High Rip Current Risk through Saturday evening for FLZ168. AM...None. GM...None. && $$ SHORT TERM...99 LONG TERM....99 AVIATION...99