####018009408#### FXUS61 KAKQ 031910 AFDAKQ AREA FORECAST DISCUSSION National Weather Service Wakefield VA 310 PM EDT Fri May 3 2024 .SYNOPSIS... A backdoor cold front pushes across the area today, leading to much cooler conditions at the coast. Rain chances return thus evening through Sunday as a series of disturbances impact the region. Summerlike conditions return to the area by the middle of next week. && .NEAR TERM /UNTIL 6 AM SATURDAY MORNING/... As of 1030 AM EDT Friday... Late morning sfc analysis shows high pressure remains SE of the area, along and offshore the Carolina coast. Aloft, a ridge axis is located just E of the area, extending into southern Quebec. Well- advertised backdoor cold front has crossed into the FA, with easterly winds and cool/moist maritime air noted along the Atlantic coast of the Eastern Shore. Already seeing a wide range in temps with 50s and 60s on the Eastern Shore and mid-upper 70s/around 80F further W. The backdoor front will continue its journey SW today, creating non- diurnal temps that will have a sharp gradient from NE to SW. Inland areas should be able to warm into the mid-upper 80s (possibly ~90) by this aftn, with falling temps as the front spreads further inland. Areas on the Eastern Shore and Northern Neck will remain in the 50s and 60s. Clouds will also increase through the day, becoming broken to overcast by the afternoon. Winds turn to the NE behind the front and become breezy, gusting to 20-25mph. There is a slight chance for showers/thunderstorms in the Piedmont this afternoon ahead of the advancing front (soundings show 1500-2000 J/kg of CAPE w/ moisture pooling along the front), but CAMs generally indicate isolated coverage. Have slightly expanded the 20% PoP eastward towards RIC. Showers likely increase in coverage late in the evening and overnight, but still look limited to the piedmont and still scattered (40-50% PoPs). Lows tonight/tomorrow morning will be a bit cooler than this morning, dropping into the 50s. && .SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY NIGHT/... As of 400 AM EDT Friday... Key Messages: - Cooler temps and low clouds expected Saturday - Intermittent precip expected Saturday and Sunday The better moisture and lift moves in on Saturday and especially Saturday night as the 850mb winds increase and have kept likely PoPs over the NW Piedmont, tapering to low chance at the coast. Even at the coast though, it will not be terribly pleasant in the morning with onshore flow, low clouds and the potential for drizzle into Saturday morning. Still undercutting NBM highs a bit for Saturday. Highs will range from the low 60s (or possibly even lower) in the NW piedmont counties and the Eastern Shore, to around 80 across the far south where some afternoon sunshine is possible. Increased coverage in showers is expected Saturday night, but still keeping the likely PoPs limited to W of I-95. The backdoor front will attempt to move back north on Sunday as the Ohio valley system approaches from the west. Showers may be more widespread on Sunday due to a weak disturbance aloft lowering heights across the region. Best moisture and still expected along/west of I-95. As such, have continued with likely/categorical PoPs over the west on Sunday, tapering to chance PoPs at the coast. Highs expected to be warmer than Saturday in the mid 70s to lower around 80, warmest SE VA/NC NC. && .LONG TERM /MONDAY THROUGH FRIDAY/... As of 400 AM EDT Friday... Key Messages... - Additional scattered showers and storms on Monday. - A more summer-like pattern with warmer days and chances for late afternoon and evening showers and storms appears to be on the way for the middle of next week. By Monday, the warm front will be well north of the area. However, the system over the Ohio Valley will be moving through during the day. Expect another round of showers/storms mainly during Monday afternoon into Monday evening as a stronger upper disturbance moves through in the W-NW flow aloft. Slightly more instability on Monday vs Sunday so more thunderstorms are expected. Most will see temps in the low 80s, upper 70s on the Eastern Shore. We get into an almost summertime pattern by Tuesday as the ridge aloft builds overhead with afternoon/evening showers and thunderstorms each day being triggered by the lee side trough. The GFS and ECMWF both suggest the ridge breaks down slightly by Wed/Thu with stronger 500mb flow of up to 50 kt by Wed afternoon. Along with this, those models suggest weak short waves (likely of mesoscale origin from convection over the Ohio Valley and central plains) moving through the area. Although we are talking about days 5-7, the relatively strong upper flow combined with relative steep mid level lapse rates of up to 7 C/km would suggest the possibility of severe weather. In fact, the CSU Machine Learning Probabilities suggest a slight risk for severe weather on Wednesday and again on Thursday. We have plenty of time to monitor this, but the area may become a little more active by the end of next week. && .AVIATION /19Z FRIDAY THROUGH WEDNESDAY/... As of 215 PM Friday... Degraded flight conditions are expected through most of the 03/18z TAF period as a backdoor cold front pushes further inland. As of 18z, IFR CIGs (bases ~800 ft) have moved into ORF and PHF. MVFR CIGs are noted at SBY, with VFR at RIC. Expect these IFR CIGs to persist along the coast through the period. Elsewhere, expect SBY and ECG to drop to IFR CIGs over the next few hrs, with RIC holding off until this evening. CIGs may then drop further to LIFR for a time tonight (best chances at ORF and ECG). Additionally, there may be VSBY reductions below 3 SM due to BR or FG. This part of the forecast is more uncertain so have not gone lower than 3 SM in the TAFs at this time. In terms of precipitation, most stay dry this aftn (a very brief shower or storm cannot be ruled out at RIC), before more widespread shower activity approaches the W later tonight into Saturday. Areas of drizzle are also possible. Winds have turned to the E behind the front at all TAF sites and E winds 10 should avg ~10 kt overnight into Saturday. Outlook...Sub-VFR conditions expected at times through through the weekend and even into early next week due to an unsettled weather pattern. A warmer, more summerlike pattern returns by Tuesday with chances for storms each afternoon/evening. && .MARINE... As of 300 PM EDT Friday... Key Messages: - Small craft advisories are in effect for the Chesapeake Bay and lower James River. Advisories were expanded south to the NC/VA border and extended through this evening. -Winds of 15 to 25 kt will persist this evening then diminish a bit late tonight/Sat morning, but winds may increase some Saturday and additional Small Craft Advisories may bee needed by Saturday/Saturday night. Winds increased abruptly as expected earlier today behind the backdoor cold front. Overall the NE winds have over-performed with some gusts of 25 to 30 kt at times over the ocean and lower Bay. SCA advisories are in effect for the Bay, lower James River and coastal waters from the NC/VA border north. Winds will persist into this evening, but should slowly decrease some by midnight. That said given the pattern and gradient winds will remain E-ENE at 15 kt gusts to 20 kt through the overnight. Seas have increased to 4 to 6 ft from Cape Charles north and 3 to 4 near the NC/VA border. Given the easterly flow seas over the ocean and waves at the mouth of the Bay may be slow to decrease overnight. Wind speeds increase again later Sat aftn/Sat night while shifting to the SE and this reflected by nearly all of the guidance. This brings another chance at SCA conditions, again mainly over the Bay. Seas remain 3-4 ft with waves 2-3 ft in the bay/rivers/sound. The front lifts back N on Sunday, shifting winds to the S. SSW winds return for Monday through the middle of next week (but likely remain sub-SCA).Southerly flow looks as though it will persist through most of next week with the next backdoor cold front possible some time Friday. && .TIDES/COASTAL FLOODING... As of 300 PM EDT Friday... Have issues a Coastal Flood Statement for locations in the upper Bay as tides increase and approach minor flood levels later on Saturday. Tidal departures will increase overnight due to winds persisting onshore from the E or ENE. Moderate levels are not expected (except perhaps locally at Bishops Head), so no Coastal Flood Watches are anticipated. && .AKQ WATCHES/WARNINGS/ADVISORIES... MD...None. NC...None. VA...None. MARINE...Small Craft Advisory until 1 AM EDT Saturday for ANZ630>632- 634-638. Small Craft Advisory until 7 PM EDT this evening for ANZ650- 652-654-656. && $$ SYNOPSIS...MRD NEAR TERM...AM/SW SHORT TERM...AM/MRD LONG TERM...AM/MRD AVIATION...SW MARINE...LKB/SW/JAO TIDES/COASTAL FLOODING... ####018004807#### FXUS64 KMOB 031911 AFDMOB Area Forecast Discussion National Weather Service Mobile AL 211 PM CDT Fri May 3 2024 ...New NEAR TERM, SHORT TERM, LONG TERM, MARINE... .NEAR TERM... (Now through Saturday) Issued at 211 PM CDT Fri May 3 2024 Isolated to scattered thunderstorms have begun to initiate across portions of the southeast this afternoon, as a weak shortwave moves through the region. Despite a lack of strong forcing, this activity has been aided in diurnal temperatures, and are expected to remain fairly unorganized. Given an abundance of moisture across the area (PWs around 1.5 inch), locally heavy rainfall will be possible, along with brief wind gusts. This activity should begin to diminish towards the late afternoon and early evening hours as the shortwave moves to the east and we lose our daytime heating. The upper flow pattern will remain fairly unchanged through the overnight hours and into Saturday, as a series of shortwaves move through the region. Without any large scale ascent, dry conditions will prevail overnight, with mid and high clouds persisting across the area. Overnight lows will fall into the 60s just before daybreak on Saturday. Patchy fog is possible once again tonight, and may be dense in some locations. However, given the cloud cover, the coverage is not expected to be widespread enough to warrant an advisory at this point. Afternoon showers and thunderstorms are expected once again on Saturday, though the coverage will be scattered at best. The better chance for thunderstorms will be over the northern half of the area, where the influence of the shortwaves may be a tad higher. Otherwise, expect highs to warm into the upper 80s across much of the area. /73 SHORT and LONG TERM... (Saturday Night through Thursday) Issued at 454 AM CDT Fri May 3 2024 Weak ridging will begin to build into the area Saturday night, with another shortwave moving through during the day Sunday. This will bring another round of isolated to scattered thunderstorms Sunday afternoon, with lesser coverage over our southern zones. Locally heavy rainfall and brief winds gusts will be possible with any storm that develops and this activity will likely diminish Sunday evening with the loss of daytime heating. Highs will warm into the mid to upper 80s by Sunday afternoon, falling into the lower to mid 60s Sunday night. By Monday, a strong ridge begins to build into the region, amplifying on Tuesday and Wednesday as a trough moves into the Planes. Dry conditions will then prevail through the remainder of the forecast period, with the main focus on the potential heat next week. Under the influence of the ridge, and after several days of persistent southerly flow, high temperatures will climb into the upper 80s to lower 90s (~10 degrees above seasonal norms). Heat indices will be in the upper 90s Tuesday and Wednesday, which may lead to heat stress concerns. Overall, though, RH will likely remain low enough to prevent widespread heat concerns. Overnight lows will fall into the upper 60s to lower 70s each night. /73 && .MARINE... Issued at 211 PM CDT Fri May 3 2024 A light onshore flow will persist through the weekend and then increase slightly during the early part of next week as surface high pressure continues to ridge into the marine area from the east. Bay waters will have a light to moderate chop through the period. Seas offshore generally remain 2 feet or less over the next few days, but increase to around 2 to 3 feet late in the weekend and into the early part of next week due to the slight increase in winds. Winds will be a little higher and occasionally gusty each afternoon near the coast in association with the daily sea breeze circulation. A few showers or storms are possible over the bays and inland waterways this weekend. /73 && .PRELIMINARY POINT TEMPS/POPS... Mobile 69 86 67 86 69 85 70 86 / 10 20 0 10 0 10 0 0 Pensacola 70 83 69 84 71 83 72 84 / 10 10 0 10 0 10 0 0 Destin 70 82 70 82 72 83 72 82 / 10 10 0 10 0 10 0 0 Evergreen 66 89 65 89 65 88 66 89 / 10 30 10 20 10 10 0 10 Waynesboro 66 88 65 88 65 89 68 89 / 20 30 10 30 10 20 0 10 Camden 66 87 66 88 65 88 67 89 / 20 30 20 30 20 20 0 10 Crestview 64 89 64 89 65 88 66 88 / 10 20 10 20 0 10 0 0 && .MOB WATCHES/WARNINGS/ADVISORIES... AL...None. FL...None. MS...None. GM...None. && $$ This product is also available on the web at: www.weather.gov/mob ####018003332#### FXUS63 KGRR 031913 AFDGRR Area Forecast Discussion National Weather Service Grand Rapids MI 313 PM EDT Fri May 3 2024 .KEY MESSAGES... - Increasing Chance for Showers/Storms Later Saturday into Saturday night - Dry end of the weekend - Many chances for rain next week && .DISCUSSION... Issued at 231 PM EDT Fri May 3 2024 - Increasing Chance for Showers/Storms Later Saturday into Saturday night Southerly winds ahead of an approaching cold front will draw up moisture from the south Saturday into Saturday night. Instability increases as well later Saturday afternoon into Saturday night, but overall remains weak. Aloft some upper level divergence is seen Saturday night over the CWA so that may enhance the lift. Thus the combination of moisture, lift and instability will likely lead to showers and a few storms. Ensemble QPF values, while low, have been trending up with the precipitation for this period. - Dry end of the weekend High pressure over the upper Mississippi Valley will produce plenty of sunshine Sunday. Highs will climb to a couple of degree either side of 70. - Many chances for rain next week The persistent upper trough over the western US is progd to cut off over the northern High Plains during the middle of the week. The result will be several short waves that move in our direction and bring chances for showers and storms. Tuesday night through Wednesday night will be a time frame that will see increased chances for precipitation. An occluded front will lift north toward Lower MI Tuesday afternoon and this will produce some showers/storms. Present indications are that the strongest instability will remain south of the state. However, that could changed this far out. SPC has already highlighted areas to the southwest of the state for the potential of severe storms. Another chance of showers/storms will come Thursday and Thursday night, when the surface low over the northern Plains moves east. Accompanying short waves and a feed of moisture rich air from the south will spur convective development during this time. && .AVIATION /18Z TAFS THROUGH 18Z SATURDAY/... Issued at 136 PM EDT Fri May 3 2024 A cold front is moving slowly across Lower MI this afternoon. A line of showers has developed along it between GRR and LAN. This line should clear LAN/JXN by 21z. Cigs are generally MVFR but a few pockets of IFR exist. Look for improvement by the end of the afternoon when VFR conditions will develop. Models show a fairly strong signal for stratus to develop over Canada tonight and move east in easterly flow. We'll see IFR develop overnight at LAN/JXN and then spread west and lift a bit as it approaches GRR/MKG. && .MARINE... Issued at 231 PM EDT Fri May 3 2024 Southerly flow will be on the increase Saturday into Saturday night as a front moves in from the west. This will be warm air advection and overall the values are expected to remain under 20 knots. Thus we don't plan on needing headlines a this time. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...None. MARINE...None. && $$ DISCUSSION...MJS/04 AVIATION...04 MARINE...MJS